Friday, December 30, 2016

Multiple timelines & viewpoints. Science fiction is international

For weekend-holiday distraction - and in our year-change mood - let's get back to Science Fiction! First, have a way cool look at the physics and paradoxes of time travel. 

A nonlinear history of time travel: Nautilus offers an excerpt from the mind-expanding experiment Time Travel: A History by James Gleick. As usual, a delightful, intellectual and verbal feast. Of course, this survey barely does credit to the array of possible means by which we sci fi authors try to weasel our way around causality and temporal protection. 


One is the Multiverse Branching Point or MBP. Take one example: when Spock accidentally lures a vengeful Romulan to go back in time and destroy Planet Vulcan (in J.J. Abrams's Star Trek reboot) many fans consoled themselves that this is just a branching-off of a newborn parallel reality... that the older timeline still stands, where Shatner-Kirk and all the rest remain, continuing along the original timeline, like a trellis for the new one to grow alongside.


I prefer that interpretation.  Indeed, it opens a way for New Spock to get advice from the old one or for mutual aid between timelines... so many cool possibilities.  The alternative -- the One Timeline Loop OTL -- betrays every single moment of joy we got from Star Trek TOS and The Next Generation and Voyager... because if that's the case, then J.J. Abrams has simply wiped every one of those adventures away and said "never mind."  Indeed, does anything Chris Pine's Kirk does really matter, if the next time traveler will simply erase all his life and deeds? In fact, what would the New Kirk do with a time machine, except go back, save his dad and restore the Shatnerian timeline?

Paramount would give us all a psychic gift, by making clear that MBP is "true." And I hope you found that timey-wimey rant entertaining!

Well, well, that's an artistic representation of one of many ways that physicists (a few) think the paradoxes might be resolved. Speaking a both a physicist and a science fiction author, I must say that this very loose partnership is one of the most fun that our unique and marvelous civilization offers, during a unique and marvelous... time. 

Explore more of the multi-dimensions of time in James Gleick's Time Travel: A History or Richard Muller's Now: The Physics of Time.

== SF from other viewpoints ==

One of the most exciting things to happen to Science Fiction in this century has been the rise of a vibrant SF sensibility and creativity among Chinese authors and directors who are starting to make waves also in the West. See this explored more fully in the article, A Brief Introduction to Chinese Science Fiction by Regina Kanyu Wang. 

Liu Cixin’s epic “Three Body” trilogy (Volume One received the Hugo for best novel in 2015), recently concluded with his latest book Death's End (read a selection on Tor's website.) 

American authors Ken Liu (The Paper Menagerie, The Grace of Kings) and Ted Chiang ( his novella Story of Your Life formed the basis for the film Arrival) have been also familiarizing their readers with vibrant stories that include Asian flavors. As have many others. Rejoice over this expansion of the Science Fiction worldview.

Invisible Planets: Contemporary Chinese Science Fiction in Translation, edited and translated by Ken Liu, presents an anthology of some of the best in recent speculative fiction from China, including powerful stories from Liu Cixin, Xia Jia, Tang Fei, as well as the excellent novella "Folding Beijing" by Hao Jingfang, which won a Hugo at the Kansas City Worldcon in 2016. Essays explore topics such as "What Makes Chinese Science Fiction Chinese?"

Chinese director Ren Chao Wang created a marvelous science fiction film “The End of the Lonely Island.” Beautifully shot and tightly logical, it weaves through flashbacks as a woman scientist desperately evades a deadly plague and panicking authorities in order to transport her software AI to a desolate isle, where it might communicate assistance to a lost starship.  I ranked this film very highly in judging for the Raw Science Film Festival, whose awards ceremony took place in Los Angeles, in December.  See Wang Renchao's official site for his film. Lovely special effects and visuals. Have a look at the trailer… though unlike the film itself, the trailer hasn’t been supplied with English sub-titles.

Science fiction is spreading, not only in China. Lately, there have been anthologies of tales by authors from Africa (Try: AfroSF: Science Fiction by African Writers) , India (The Scientific Indian Science Fiction Anthology), Iraq (see below), and by Latina/Latino authors... 

Looking beyond magical realism: Sample some recent Latin short fiction in Latin@ Rising: An Anthology of Latin Science Fiction and Fantasy, edited by Matthew David Goodwin. This collection includes speculative fiction stories by Juno Diaz, Daniel José Older (author of Shadowshaper), Alex Hernandez, Kathleen Alcala and other Latino/Latina writers residing within the United States. For a vivid SF film set on the border, watch Sleep Dealer, directed by Alex Rivera.

Now comes the vivid anthology Iraq+100: Stories from a century after the invasion, a collection showing that unlucky country in a century’s time, as portrayed in both Arabic and English by Iraqi writers. From NPR's review:  “In Khalid Kaki's "The Day By Day Mosque" the narrator drinks vinegar made from hundred-year-old perfume in a world where everything is in the process of being literally reversed; in "The Here and Now Prison," Jalal Hassan imagines the city of Najaf and its residents translated into virtual reality; in "Operation Daniel," people who resist a dictator's edicts are "archived" — incinerated and compressed into the diamonds that stud his shoes.”  Wow.

See also The Best American Science Fiction and Fantasy, edited by Karen Joy Fowler and John Joseph Adams, with stories by Salman Rushdie, Charlie Jane Anders, Ted Chiang, Catherynne Valente and others.

== SF'nal TV and movies ==

I’ve not yet seen the Westworld TV series on HBO (except glimpsing a bit, in a hotel room.) But this article shows how the writers seriously intended to play with one of the coolest sci fi-ish concepts in psychology, using ideas from The Origin of Consciousness in the Breakdown of the Bicameral Mind, a blockbuster 1976 book by psychologist Julian Jaynes... that I read way back when. Unintentionally, perhaps, Jaynes wrote what I deem to be one of the finest sci fi gedankenexperiments since Karl Marx. Things that aren't likely to be or come true... but make us re-evaluate other things we were definitely wrong about.

Cool coming sci fi flick that appears to intend to offer real science fiction. See the preview for Passengers starring Jennifer Lawrence and Chris Pratt.  

== Clever styles of propaganda ==

Who needs privacy? Sharing is Caring. Secrets are Lies. See the preview for The Circle, starring Emma Watson and Tom Hanks, based on the book by Dave Eggers. The novel was an exquisite exercise in the art of propaganda, in which the author gives nearly all of the speeches and lecturing advocacy to those he deems evil - those promoting transparency and openness.  By hammering the reader with patronizing rants and making his protagonist deliciously stupid, he invites readers to get their hackles up against the idea that she believes... and that the author hates. I've never seen it done so well. We'll find out if the flick also uses this effective Orwellian technique.

(O.S. Card does the same thing, portraying Ender as so guilt-ridden over things that weren't his fault that the reader is soon practically begging Ender to both forgive himself and take over ruling humanity's destiny. Some trick!)

In a highly intelligent and perceptive rumination about the coming “Rogue One” Star Wars flick, Thomas Ricard riffs off some of my earlier points about the troublesome ethical/moral and logical problems of the Jedi Order.  My own hopes are up – a little – with the news that there won’t be any damned “Force” mutant-demigods in the coming film. Resistance to evil is about people – regular or above-average people – rising up to confront it (as I portray in the Postman.) Chosen-One mutants – even in adventure stories – don’t help us figure out that central problem. They just distract from it.

Get Star Wars on Trial as the perfect gift for your jedi-fanatic!

== Better legends ==

The Fifth Element was writer-director Luc Besson’s “delightfully garish, unapologetically maximalist space-jam—and the film that proved that, in space, everyone can hear Chris Tucker scream.” His more serious contemplation of human augmentation was also great — “Lucy.”  So you can bet that — especially after watching this trailer (!) — I’ll be lining up next year, for Besson’s “Valerian and the City of a Thousand Planets.”

From Entertainment Geekly: A cool fun personal analysis of what makes Star Trek II: The Wrath of Khan one of the finest science fiction films of all time.

What fun. An appraisal of all the different timelines in Back To The Future. Hilarious, and there are a dozen you never realized. Well, I think the fellow adds maybe six unnecessary ones. Still, such fun. 

== And prophetic works... ==


As we being our long process of saying goodbye to Miami… then all of Florida and much of the Olde South… I am reminded of the scary novel War With the Newts,  a 1936 satirical science fiction novel by Czech author Karel Čapek. Humanity loses all its lowlands which are converted into swamps for the intelligent salamanders we had abused.  A different mechanism (one reminiscent of Uplift!) But the net result - humanity fleeing from the shorelines - is eerily and painfully redolent.

Čapek, who is best known for R.U.R. (coining the term “robot”), also wrote The Absolute, a satiric (1922) prediction of vast, worldwide war in 1943, though triggered by a new form of energy generation that fills the world with a pollutant — religious irrationality. Geez, what if it’s true? If you look at where and how fossil fuels get mined and burned and who controls them.  Just sayin’. 

(Forget robots and drowned coastlines. Čapek might have been especially prescient to connect energy sources with a rise in human irrationality. See how I was personally involved - way back in 1970 - in an endeavor that helped get the lead out of gasoline, resulting , science now confirms, in a plummet in violence 20 years later, after each nation made the shift. And yes, at one level it is Čapek's silliest, yet most profoundly true prediction. The guy is amazingly under-rated.)

In Defense of The Postman: Here’s a thoughtful rumination on Kevin Costner’s film version of the novel.  Why is The Postman set in Oregon? How did the film fail and succeed? Did it have much in common with the book? Anthony Rimel's article in the Corvallis Gazette-Times discusses this and much more -- like whether citizenship can prevail. See Eight of the great survivalists from science fiction: The Postman stands with Sarah Connor and Mad Max. 

And finally... Beyond Mad Max: Ten extreme post-apocalyptic scenarios in film and novels.

90 comments:

Louis Shalako said...

Huh! I got giant mutant salamanders in a book too, 'Core Values'. Sorry for the naked and unabashed plug.

Peregrin said...

I always enjoyed The Postman - both book and movie - for the same reason: they offer hope for our future, no matter what setbacks we may suffer. I plan to pop in the DVD and rewatch it soon, because I need a shot of that hope these days.

Alfred Differ said...

@LarryHart: Kiln People was a hoot, but through an unfortunate coincidence, my father passed away as I was reading the last few pages. That gave the final scenes a different emotional flavor than they might have otherwise had. I had the book with me in the hospital while we waited. 8)

I suspect the truth of the matter when it comes to copying people is that there is a continuum of options. For casual acquaintances, we probably start with a stereotype and modify it slightly with what we learn of them. For friends, the modifications may begin to dominate our mental model of them. For adult family, we might start with a model of another family member and then add mods. For kids, I suspect parents start from scratch and then try to mold a child to match what they’d like to see. Of course, the kids are returning the favor and molding their parents in return. For lovers… well… my deep suspicion is that the hormones are for stopping us from thinking too much about what the other is like and instead motivating us to become what they would like us to be. Lust isn’t love in the sense Hofstadter addressed in the Strange Loop book, but the hormones/neurotransmitters certainly impact us functionally.

Love is an overloaded term in English. The copying part of it is associated with paying attention to another person enough to learn about them. Even something as small as asking someone what their favorite thing to eat at breakfast is and then remembering it counts. The copies start as low fidelity versions, but over time they can advance to hifi versions if we are properly motivated.

I think Jumper has it right when it comes to copying a whole village. If some alien shows up and abducts me tonight to have a human for their zoo, they will only get a partial human as far as I’m concerned. It’s not just that my behavior shifts around me wife, son, and friends, though. When I’m near someone with a hifi copy of me, I can see myself reflected in them. That changes my Smithian Impartial Spectator in a way that a lowfi copy of me cannot. My hifi copy of them links up to them too. If there were any ultrasonic signals passed, I’d call us Tines. 8)

Tony Fisk said...

John Wyndham also covered the effect of rising sea levels in "The Kraken Wakes".
Čapek clearly got in first, although Wyndham gets a nod for depicting scientists' inability to capture the public imagination as to the consequences of climate change.

Chiang wrote the short story which was the basis for "Arrival", which is well worth seeing.

From half a world away, the first thing my 14 yo daughter decided to do on hearing Trump had won was to rewatch Hunger Games. A charming tale, with chillimg elements (the dystopia *will* be telecast, with spin!).
Is it just me or did the head of District 13 resistance bear an uncanny resemblance to a certain presidential candidate?
Oh, well. Remember to click your heels and salute the new Chief in the new style come Jan 20.
...and don't forget to give a little whistle ;-)

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David Brin said...

Life keeps showing us the vast range of humans. It's not just the spectrum of good and evil, but also smart and stooopid.

I do not fear evil geniuses much, because some of them can be shown self-interest. It is the Idiocracy party, filled with morons who bitterly hate and rage at those who simply have lots and lots more sapience and brains.

shakatany said...

Haven't read Gleick's book yet but time travel, as depicted in popular culture, is impossible for one very simple but often ignored reason: there is no there there, no permanent firmament. If you could go back in time by even one day you'd find yourself trying to breathe vacuum.

Every day the Earth moves 1 million miles in its orbit around the sun. If you think we could travel from 2016 to 2015 (to change the election) think again. The sun and its solar system travels at 600,000 miles per hour around the center of the Milky Way taking about 225-250 million years to complete one orbit (a galactic year). Plus the Milky Way and its satellite galaxies are heading toward the Great Attractor at about 14 million miles per hour. Everything is in motion out there - it's just that it makes so little impact on us here on Earth that we overlook it.

If that Romulan spaceship went back a century and a half or so in time it would have to travel an unbelievable amount of space to find where the Earth and Vulcan were and how would Nero know exactly where they would be located? Plus the universe has also expanded a bit in the time between the two events. (And why didn't he just go back to his homeworld and warn them what would happen in the future?)

LarryHart said...

Alfred Differ:

Lust isn’t love in the sense Hofstadter addressed in the Strange Loop book, but the hormones/neurotransmitters certainly impact us functionally.


I wasn't exactly equating lust with love, but there are times when what I'm trying to do with a lover is more "consume" than "copy". And yet, I'm definitely feeling love at the time.

Desire and gratitude seem to be components of romantic love for me, and I'm not quite sure how "copying" fits in there.


Love is an overloaded term in English. The copying part of it is associated with paying attention to another person enough to learn about them. Even something as small as asking someone what their favorite thing to eat at breakfast is and then remembering it counts.


And sometimes, it just doesn't work properly, which can lead to real-life sitcom scenes. My parents were married for almost 55 years before my dad passed away, and they were a model happy couple of their generation, but for their entire married life, Dad just could not remember the fact that Mom doesn't like orange juice for breakfast. It's not that copying wasn't taking place, but it was flawed in very particular ways.

LarryHart said...

Tony Fisk:

Chiang wrote the short story which was the basis for "Arrival", which is well worth seeing.


Coincidentally, my family and I just saw it this evening. The beginning reminded me of the Star Trek TNG episode "Darmok", and I was kinda hoping for a climactic scene where we can actually understand...well, no spoilers. Certainly an interesting take on perception of time. And I believe someone on this list once pointed out the fact that it talked about positive sum games (though it used the more ambiguous term "non-zero sum").

From half a world away, the first thing my 14 yo daughter decided to do on hearing Trump had won was to rewatch Hunger Games.

I should do that too. That's another series I learned to love from my teenager.


Is it just me or did the head of District 13 resistance bear an uncanny resemblance to a certain presidential candidate?


That might be a Roarschach Test kind of thing. I can see how certain people might think of a coldly-calculating female leader in pants resembles Hillary, but to me, it was the 60-year-old Princess Leia who bore resemblance to that candidate.

Oh, well. Remember to click your heels and salute the new Chief in the new style come Jan 20.


JOIN! THE! MOCKINGJAY!

LarryHart said...

shakatany:

but time travel, as depicted in popular culture, is impossible for one very simple but often ignored reason: there is no there there, no permanent firmament. If you could go back in time by even one day you'd find yourself trying to breathe vacuum.


I disagree. I've had this argument before, though not (I think) here. But I think the depiction of a time machine in the 1960 movie of "The Time Machine" makes it clear how this "works". The time travel effect propels the machine through the fourth dimension, but its motion in three dimensions remains unimpeded.

When you drive a car through two dimensions, you don't have to take the rotation of the earth or the motion of the planet through space into account. All that is done for you the way it happens as a pedestrian. All you do with the car is add additional force along vectors on the earth's surface to affect your relative motion.

When you jump or leap up in the third dimension, why do you fall down in the same spot of the earth's surface, rather than millions of miles away in space? Because your motion in the x-y plane doesn't change just because you've applied a separate force in the z direction. I assert the same principle applies to HG Wells's time machine. An impulse to move forward or back in the fourth dimension doesn't affect your existing motion in the original three.

Jonathan Sills said...

Dr. Brin, it is explicit in the dialog in the '09 Star Trek movie that they're in an alternate timeline, similar to the way the universe(s) is/are set up in the ST:TNG episode "Parallels" (where Worf begins sliding through alternate universes, from his home timeline to one where he placed third in a bat'leth tournament instead of first to eventually one where he was married to Deanna Troi, with two children, and was first officer of the Enterprise under Capt. Riker - and then millions of alternate Enterprises begin appearing in the area...). The original timeline is still intact, as seen in the MMO Star Trek Online (whose timeline begins 22 years after the Hobus supernova propagated through subspace to destroy Romulus, and part of the fun is finding out how and why).

Shakatany, Nero didn't try to warn Romulus because he was by that point thoroughly insane. (Remember when the Kelvin's captain tried to tell him Romulus was still there? "Don't tell me it wasn't destroyed, I saw it!!") The only thing he could think about was exacting his revenge on Spock, because he had come to blame Spock for the whole thing. (Destroying the homeworlds of the Federation was just a bonus.)

David Brin said...

shakatany (and the rest) Benford’s TIMESCAPE aims a beam of tachyons at the point in space where Earth WAS 20 years before.
Go listen to Monty Python offer some perspective:
https://www.youtube.com/watch?v=JWVshkVF0SY
or
https://www.youtube.com/watch?v=44DlSj6bnn4

If fact, this one typifies how we feel about 2016,
https://www.youtube.com/watch?v=JWVshkVF0SY

Zepp Jamieson said...

I just got done watching a musical/comedy show called "The Entire Universe" with Professor Brian Cox, Eric Idle, and a troupe of cougars, funnymen and a dwarf. Cox probably didn't do himself any favours getting in such a dubious project, but it did have its moments--not least of which was the grand finale musical number. Eric Idle, so can pretty much guess what it was.
It's a bit past the season, but here's a link most people here will enjoy: A Scientific Christmas
https://www.youtube.com/channel/UCeMZ98B_0RXAZDOaKP_NfgA

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greg byshenk said...

Tangent from the last thread:

John Sears said...
Amazon.de, unfortunately, makes it difficult to discern the language in which books are written, so one like me who prefers to read in English must be very careful when buying.

You might check what the costs are (including shipping) on Amazon.co.uk. I occasionally order from them, and it seems shipments (to the Netherlands) usually come from Germany.

Jumper said...

Actually if you jump straight up you land in a different place. Just sayin'.

raito said...

Once again, I miss a post transition...

Dr. Brin,

Re: wootz
If I misread secrecy as suppression, then I apologize. Different mechanism entirely. But it still fits, as the process for making the stuff was well-known -- they just didn't know at that time what the differentiating factor was.

And as we agree, there's so many possibilities.

If I had a better memory for titles and authors, I'd be able to cite one novel. It's of the type where the stranded Earthman needs to get somewhere, but the local culture is completely balkanized by their guilds. So he needs to do things like make a battery, but the copper guys won't talk to the chemical guys.

That's the sort of thing I think you (and I) rail against. Not making progress because the elements of progress just aren't mixing. Hamming knew this, which is why the math guy sat with the physicists and chemists at lunch in Loa Alamos. You
'd probably like his musings on research and progress.

LarryHart said...

@raito:

That's the sort of thing I think you (and I) rail against. Not making progress because the elements of progress just aren't mixing. Hamming knew this, which is why the math guy sat with the physicists and chemists at lunch in Loa Alamos.


Just yesterday, someone mentioned the movie "Arrival". Toward the beginning, the linguist and the physicist snipe at each other over which questions to ask the aliens, at which the military commander remarks something along the lines of "That's why you're working together", or maybe it was "That's why you're both here."

In any case--and I think this was remarked on here before I saw the movie--this one did a good job of not following the "institutions are incompetent" idiot plot.

Paul451 said...

PaulSB,
Re: Wix comic.

The site loads eventually, but it is slow and glitchy, causing weird interactions with Firefox's chrome (UI). It got slower and slower with each page.

(Firefox, Win7, old computer.)

I don't think it's the animated background, I think it's Wix itself. Their home page does the same thing, as did the handful of other wix.com hosted sites I went to. It seems a very script heavy system, therefore processor demanding, but without a good fall-back design (so if a script hasn't run yet, the site simply hangs or fails rather than defaults to a simpler design while the complex elements load in the background.)

(Also, if your daughter included any navigation controls, they don't appear. I have to use the menu-bar and select each page individually.)

Paul451 said...

LarryHart,
Re: Alfred's copying metaphor.

Romantic love is chemical (our old friends oxytocin/dopamine/etc.) Companionate love is more neuro-structural, periodically reinforced by burst of associative-triggered chemicals.

The initial high levels of chemical is to give you a reason to spend enough time to structurally incorporate the other person (or animal) into your brain. (**) When familiarity reduces the dose of the chemicals, you've switched to companionate love.

Losing your True Love is like going through a drug withdrawal. Losing your real love is like an amputation.

That's why I don't think... was it PaulSB's example?... of someone trying to leave their poverty trap, but not being able to get on the boat... would be due to oxytocin-addiction. Rather, a major social upheaval like that is like being asked to voluntarily amputate your legs. You can't (as Alfred mentioned with his alien zoo example) take all of yourself with you.

** (However, the chemicals distort the accuracy of your copy. The inaccuracies can be enough to destroy the relationship because this is literally "not the person I fell in love with", which starts to trigger revulsion towards the imposter.)

Re: Mom's orange juice.

That gets back to the way memories (and hence presumably these "copies) are actually made; versus the Hollywood image of memory as film-like recordings (naturally).

Just as memory is a set of associations that essentially serve as instructions for parts of the brain to recreate the original sensations (and therefore is modified by changes in those parts of the brain), the "copy" of your companion is being imprinted into your sense of self. Your sense of another person is going to become jumbled with your own subconscious desires, tastes, preferences, etc, because that's how you experience that other person. The "copy" isn't a separate "file", it's actually a part of your sense of self, no clean boundaries.

In your father's case, his sense of breakfast with your mother involves himself drinking orange juice. Breakfast means your mother, and it means orange juice. The two associations become physically crossed. Therefore making your mother breakfast would involve giving her orange juice.

Paul451 said...

shakatany,
"but time travel, as depicted in popular culture, is impossible for one very simple but often ignored reason: there is no there there, no permanent firmament. If you could go back in time by even one day you'd find yourself trying to breathe vacuum.
Every day the Earth moves 1 million miles in its orbit around the sun. [...] "


1 million miles relative to what?

Time travel is likely to be a relativistic phenomenon (or beyond relativity.) "No permanent firmament" means no absolute frame of reference. Therefore it's just as likely that time-travel is dimensionally anchored to the local frame of reference, ie, if you start on Earth, you are anchored to Earth's world-line. Because relativistically, the Earth really is the centre of the universe.

LarryHart,
"When you jump or leap up in the third dimension, why do you fall down in the same spot of the earth's surface, rather than millions of miles away in space? Because your motion in the x-y plane doesn't change just because you've applied a separate force in the z direction."

Of course, if you leap high enough, you keep going.

Perhaps if you time-travel too far from your point of origin, you likewise achieve "temporal escape velocity" and separate from this time-line. Perhaps never to return.

Maybe that solves the time-travel paradox. (The time-travel version of Fermi's Paradox. "If time-travel is possible, where are all the time-travellers?") We're far enough away from the earliest point where time-travel was invented that they can't come back this far without falling out of this time-line. And time-travel (and people) exist in such a small proportion of alternative time-lines that it's extremely unlikely that a time-traveller falling off another time-line will end up in ours.

David Brin, Jonathon Sills, et al,
Re: Star Trek and multiple time-lines.

That would make an interesting solution to all the notorious Star Trek inconsistencies over the multiple series and movies...

None of them are set in the same time-line!

David Brin said...

"Losing your True Love is like going through a drug withdrawal. Losing your real love is like an amputation."

Quotable!

LarryHart said...

Ok, I just saw "Rogue One".

This was the "Star Wars" movie I've been waiting for since ESB. In fact, back when I was hearing that there was going to be one prequel to Star Wars, I imagined something which would end with the rebels' "first victory against the evil galactic empire". The biggest difference being that the movie I imagined would have had Jedi knights and light-saber battles.

Not wanting to spoil too much, I'll just say that there's one piece of continuity that I wonder about. C3P0 and R2D2 make a quick cameo appearance toward the end, watching rebel ships take off for the battle. So how are they on the ship at the beginning of Star Wars? Did I miss something, or is that a continuity error?

Still, for anyone who liked the original movie and suffered through the prequel trilogy, I'd recommend this one.

LarryHart said...

Paul451:

Of course, if you leap high enough, you keep going.

Perhaps if you time-travel too far from your point of origin, you likewise achieve "temporal escape velocity" and separate from this time-line. Perhaps never to return.


Well, not if you have a means of propulsion back in the down direction.

My point was that propulsion along the time dimension wouldn't have to affect the time traveler's motion through space. You stay in the same "spot" on earth for the same reason you normally do--inertia and friction with earth's surface.

This relies on a perhaps-unconventional view of a time machine which I imply from the scenes in the 1960 George Pal movie in which the protagonist watches time go by at high speed outside. He doesn't "pop" into the future, but really travels through time the way a car or an airplane travels through space. To me, that means the machine is there in all of the intervening moments, and that an outside viewer would see the machine sitting there in the same spot, only the time traveler would appear to be moving quite slowly.

With that in mind, the machine doesn't have to worry about earth's motion through space any more than a car or a train or an airplane has to do that.


Maybe that solves the time-travel paradox. (The time-travel version of Fermi's Paradox. "If time-travel is possible, where are all the time-travellers?") We're far enough away from the earliest point where time-travel was invented that they can't come back this far without falling out of this time-line.


Interesting. In space-time, there are moments which are "space-wise separated" from each other, meaning that there is no possible way for information to be shared (at the speed of light) between them. One can even argue that there is no objective way one can identify which of those moments comes "before" the other in time--it all depends on frame of reference. You seem to be suggesting a similar relationship between "moments" in a continuum of separate timelines between which travel is possible.

Re: Star Trek and multiple time-lines.

That would make an interesting solution to all the notorious Star Trek inconsistencies over the multiple series and movies...

None of them are set in the same time-line!


I've been using that to resolve differences between originals and prequels for years now. No one seems to write a true prequel that is consistent with the original, but rather something more like a re-imagining of the original. For example, the tv show "Enterprise" was supposed to be taking place a century or so before the original Star Trek, but they were already encountering Romulans and Ferrengi, which were being encountered for the very first time in TOS and TNG respectively. The only way "Enterprise" makes sense is if it is a separate timeline from TOS.

I also like to imagine that the Star Wars prequels are a separate timeline from the original Star Wars and ESB. I can see "Return of the Jedi" belonging to the timeline of the prequels, but not the first two. In fact, RotJ might make more sense if the Death Star they battle in the film is that timeline's only Death Star, rather than it being a second Death Star.

TCB said...

Nearly midnight Eastern Standard Time. Here's hoping that 2017 is not a year of things falling apart (like 2016, or at least the second half of it for me). Let it be a year of things getting put back together.

Benford's Timescape, really good book. Much of it happens in a near future of environmental collapse and hopelessness, and living not far from the drought-driven fires in the Appalachians just before the Trump Catastrophe, and smelling smoke for weeks, felt a lot like that book to me.

In a Block Universe, each moment in time is like a still frame from a movie. Time travel in a block universe would consist of finding a frame exactly like the one you want to enter, matching the arrangement of matter/space/energy fields in that moment as closely as possible.

In that scenario, time travel would require vast amounts of information processing... so vast that it would presumably be equivalent to the energy expense involved in other time travel methods (in other types of universe), which is to say nigh infinite for our purposes.

Alfred Differ said...

Paul451 beat me to a response for Larry and nails it I think. My first thought on reading about the orange juice was that I'd bet big money Larry's father really, really liked orange juice. Copies of others don't run independent of the primary personality in a stable adult. Also, copies of others don't have to be perfect any more than DNA copying is when cells split. There are advantages and disadvantages to this imperfection, but I'd start with a simpler idea that humans are relatively new on the Earth and that this function is what marks our success. We are social animals on a band scale and xenophobes at global scale which makes trade difficult, but people who can copy each other a little better than others have a biological advantage even if the copying is less than perfect.

I suspect the copying act is more of an 'onto' map for young children and an 'into' map after their sense of self grows large enough. In adulthood, I suspect we start with templates and mod them for most people we meet. For lovers, I also suspect we keep parts of a template and ignore input that conflicts if that input might demonstrate something undesirable about them. Dissonance is less painful than amputation, hmm?

I love the quotable too.

I would also like to extend the zoo example slightly to try to cover the 'get on the boat' issue. My abducted self would suffer the amputations, but so would the hifi copies within me. Every time I thought of my wife and close range family, those partial selves would feel like they had been cut off from their primaries. Spreading a self/soul around among several brains is a pretty good trick for keep one person tied to a social group. Spreading them all around within the group should be a decent explanatory theory for our loyalty to each other and our faith/sense of identity. If this is what we are doing, and I suspect it is, then stereotypes/social templates are just compression techniques for copying with the large amount of detail to be processed.

I have a couple of books on my shelves that address scholastically the details of human migrations. One big lesson is that migrating individuals are very rare. Even when faced with near certain death, many of us just hunker down and hope for a bit of luck. Getting us to move almost requires whole bands of us to coordinate, so thinking of individuals as social atoms is simply wrong. We don't get on the boat easily unless our identity group does.

This has serious implications for those of us who would like to see our civilization turn into a star-faring civilization.

This is also the reason I disagree with David on the immorality of enabling family members to easily immigrate legally to the US once one or more of them get here. If one of them has the courage to risk everything to get here, I want the whole identity group containing that individual to get here if they so want. I ALSO want the best and brightest, so this isn't an either/or thing for me. I want both.

LarryHart said...

A few minutes to midnight New Years here in Chicago.

Ordinarily, the New Year seems like a rebirth or some kind of fresh start without baggage, at least for a short while (the first reported murder of the year usually starts breaking the spell). This year, I find it hard to think that way.

Nonetheless, in the spirit of optimism, I will approach the new year without anticipating the negativity, but rather letting it prove (or disprove) itself before rendering judgement. In the meantime, best wishes to the regulars on this group. So Happy New Year, one and all.

Alfred Differ said...

I get a case of mental hiccups each time I consider time travel. So many ideas out there start with a physical model that assumes absolute reference frames. Physicists ruled those out a while ago. The second error involves many models separating time and space as if one of them could be traversed and not the others. We ruled those options out too. We know that what we think of as 'our clock' is just the direction we happen to be going. With no absolute measures, we have no choice but to accept everyone having their own clock. The coordinates we extend from our clock paths are just an overlay we use to grid the universe.

(If it isn't obvious, the notion of a universe that involves still frames in a movie either has an absolute time dimension or a preferred one which is a serious breach in the symmetry we think exists.)

Whether one warps space to wrap out clock paths back on themselves or arranges to scatter all their particles off of a few bazillion gamma-rays and hope for a bit of luck so all the particles scatter backward at essentially the 'same time', I'm not offering to be an experimental test subject. Sounds unhealthy to me.

What I think is more fun to contemplate are some of the crazy ideas for what people think gravity is. Has anyone read up on the notion that gravity is an entropic force? Weird. There is an odd symmetry between theories that treat the universe as a holographic image on a surface and a 'field theory'. Holograms encode extra dimensions as information on a surface. The dimensions appear to be there without needing to be there. How do you get time travel in a screen? Heh.

LarryHart said...

Paul451:

In your father's case, his sense of breakfast with your mother involves himself drinking orange juice. Breakfast means your mother, and it means orange juice. The two associations become physically crossed. Therefore making your mother breakfast would involve giving her orange juice.


I get that, but something more was going on after decades of her saying "You know I don't like orange juice at breakfast" in an exasperated voice. And Dad wasn't trying to annoy her. So it was more like, he could not acknowledge the separation of orange juice and breakfast. That was too weird for him to internalize as a normal thing.

In contrast, when I first started dating the woman I married, I liked to show off for her by cooking. But after the first time I made her a huge breakfast, I learned that she isn't a huge-breakfast person. She's the type whose stomach doesn't really wake up until later. So I learned something new, and that was that. It didn't take me years, let alone decades, to understand that making her a huge breakfast is counterproductive.

An even better example, though I'm going to change the names to protect the innocent. My brother's wife has a diminutive of her name that she does not want used in the presence of her students or fellow faculty members. I don't want to use real names here, but it's as if her name was Gwendolyn, but friends and family call her Jenny. And she'd find it embarrassing to have her professional acquaintances know her by the shorter name. My brother is incredibly competent at always referring her by the correct name for the situation, and not slipping up, even occasionally. My sister-in-law things he is wonderful for that, and he certainly is, but all he's doing there is to not be dismissive of the importance of a distinction to his wife. What most people would do is to pooh-pooh her feelings, and either go "I call you Jenny, so that's always what I'm going to call you," or else something more like "It's not important enough for me to bother caring." By the mere mental commitment not to dismiss his wife's desire on the matter, he gets to appear super-humanly heroic.

LarryHart said...

Alfred Differ:

(If it isn't obvious, the notion of a universe that involves still frames in a movie either has an absolute time dimension or a preferred one which is a serious breach in the symmetry we think exists.)


There's a great book by Scott McCloud called "Understanding Comics" in which he tries to explain the form of comics without regard to the specific content or genres. One point he mentions in there is that we have been "trained by photography" to think of a single panel or image as all taking place at the same moment. He plays with the idea by having a very long comics panel with dialogue that must necessarily be read successively, some lines responding to earlier ones, and the characters taking actions that correspond with the dialogue (like moving a chess piece while saying "check!"), thus making it absolutely clear that the entire frame can't possibly be taking place at the same time.

Now that cell phones can take "panoramic" pictures, where you slowly pan in one direction and get a loooooooong picture, my cousins like to play on this idea by having one of the young kids in the picture at the start of the pan shot, then once he's out of range, he runs around the back of the table and ends up on the other side of the pan shot in time to appear over there as well. You end up with what looks like one very long photograph, but the same kid is on both the left and right side.

That seems like a variation on the theme of a high-society New Years thing I heard about yesterday--that for $185,000, you can join in a New Years Eve party in (I think it was) Singapore, and then be flown in a fast jet across the dateline in time to celebrate the same New Years Eve in California. That's probably the closest we'll get to real life time-travel other than the usual "forward one second per second" that anyone can do.


What I think is more fun to contemplate are some of the crazy ideas for what people think gravity is. Has anyone read up on the notion that gravity is an entropic force?


No, but I have heard it described as the relationship between two vehicles (or pedestrians) moving along parallel lines of longitude toward the same pole. In the frame of reference of each vehicle, the other is moving parallel to it, and yet, some "mysterious force" is drawing them closer to each other until they eventually collide.

LarryHart said...

Alfred Differ:

I get a case of mental hiccups each time I consider time travel. So many ideas out there start with a physical model that assumes absolute reference frames. Physicists ruled those out a while ago. The second error involves many models separating time and space as if one of them could be traversed and not the others. We ruled those options out too.


I think the problem we run into when contemplating time travel is that we start using temporal words like "travel", "change", and such, whose definitions imply some activity over time to begin with. When you travel in space, you move a certain number of miles per second. To travel through time, then, you're trying to talk about moving a certain number of seconds per second. What does that even mean? Or if you talk about going back and changing the past--"changing" relative to what? "Changing" means to make something different from what it had been before. "Before" is a word that only has meaning within the normally-understood concept of time.

We can say that time travel means getting to the future (or past) without aging a corresponding amount--doing so in a small amount of "subjective" time. But we have to be careful there as well. Subjective time moves "slower" for someone (say) suffering painful sciatica than it does for someone enjoying a romantic getaway in luxurious surroundings with a hot chick (or equivalent), but that's not generally what we mean by time travel. I can time-travel eight hours or so in almost no subjective time by the expedient of sleeping, but that's also not generally what we mean by time travel. Near-light-speed travel in which you fly to another solar system for (what seems like) a few months and then return to an earth that is 80 years older than when you left--that's maybe the closest thing we have to "traveling to the future". And yet, even then, I'd say what's really happening (or at least "really happening") is that your apparent subjective time, not the universe's time, is what is being altered. In any case, none of this allows you to reverse the process--to return to your "starting" time--or to go backwards in time to kill Hitler or see Jesus riding dinosaurs.

In other words, without resorting to sci-fi or fantasy concepts, we can't describe a way to do the neat kinds of things that make time travel stories so popular.

LarryHart said...

speaking of time travel...

How the heck did the makers of "Rogue One" travel back in time to film new scenes with Peter Cushing's face and voice as Governor Tarkin? Some of that didn't look or sound like it was available on the cutting room floor--that bit about "We don't need a manifesto," for example.

That blew me away as much as anything else in the movie. Am I right to suspect we'll soon be seeing new movies starring Humphrey Bogart or Ingrid Bergman? Hey, I'd pay to see new Batman or Avengers episodes starring the younger Julie Newmar or Diana Rigg!

SPAGHETTI HORROR said...

*SPOILERS*

They are seen as the ships take off at the very beginning of the space battle, but the ship they are in on New Hope is the one that they rush to meet at the very end, it wasn't part of the convoy. They would have boarded that one in anticipation of the plans being delivered.

LarryHart said...

@SPAGHETTI HORROR,

Ok, then, if that ship with Princess Leia and the droids is being actively pursued from battle by Darth Vader all along, how could that ship's captain or the princess even try to claim it to be a counselor's ship on a diplomatic mission for Alderaan?

Come to think of it, did the Death Star really need "an effective demonstration" of it's power just a few days after being used for that very purpose on actual rebel targets? Wasn't the Death Star being declared "fully operational" for the first time in the original movie, after Princess Leia was already a prisoner?

Oh, "Rogue One" was an enjoyable movie and all, but I might have to relegate it to an alternate timeline after all. Pity.

Jeff B. said...

LarryHart,

No, but I have heard it described as the relationship between two vehicles (or pedestrians) moving along parallel lines of longitude toward the same pole. In the frame of reference of each vehicle, the other is moving parallel to it, and yet, some "mysterious force" is drawing them closer to each other until they eventually collide.

Not sure if it's the same thing, but I've read somewhere about a nautical phenomenon that matches what you're describing- two ships, matching speed and course, if the stray closer than a certain distance, are "attracted" to each other, and the helms must be very wary and active to avoid eventual collision. I'd assume some sort of low pressure region forms between the two parallel surfaces, pulling the vessels together.

Geez, just remembered the source- Sir Terry's Unseen Academicals again. Worth a fact check, I think, if I can find a good reference...

TCB said...

Jeff B., that's the venturi effect, and it can also cause aircraft to collide when in close formation.

For example.

Anonymous said...

http://www.abreureport.com/2017/01/henry-kissinger-clinton-family-in.html

LarryHart said...

Jeff B:

Not sure if it's the same thing, but I've read somewhere about a nautical phenomenon that matches what you're describing- two ships, matching speed and course, if the stray closer than a certain distance, are "attracted" to each other, and the helms must be very wary and active to avoid eventual collision. I'd assume some sort of low pressure region forms between the two parallel surfaces, pulling the vessels together.


That's quite interesting in its own right. However, it is a different thing (though not the opposite thing) from what I was describing.

Think of longitude lines on a globe as representing time-lines for different objects separated in space. The distances between the objects in 3-space are represented by separation along lines of latitude.

Now say the "forward" direction in time is "toward the North Pole". As two different viewpoints move forward in time without any propulsion through spatial dimensions, their mappings on the globe each move north through latitude lines without altering their longitude coordinate. Yet, "somehow", they end up being "pulled" closer and closer to each other as "time" progresses. On the globe, there is no actual force moving these objects together. The "attraction" is a function of the curvature of the globe.

The idea I was describing was that gravity works that way. The curvature involved would be in the fabric of 4-dimensional space-time, and rather than being a fixed globe, the local curvature would be caused by the mass of the objects themselves. But the effect is the same--there is no real "force" pulling you toward the earth, but as you and the earth each move forward in time, your timelines bend toward each other. I'm not sure I completely buy that theory, but it does make for interesting speculation. It helps explain why gravity seems to work more like a perceived "force" (like centrifugal force) than an electromagnetic force, which requires a charge to do the attracting or repelling.


Jumper said...

After healing I travel back in time to warn my earlier self not to take a ski trip - I broke my ankle. While 30 days in the past, after delivering my warning, we chat. After a two-day visit, I set my time machine wristwatch to forward.
What happens to my earlier self? He lives normally up to that future point and suddenly sees me pop in. There are two of us now. What happens next?

LarryHart said...

Jumper,

It depends on how the time travel mechanism "works".

In some views, traveling backwards in time just means your consciousness runs in the opposite direction though your personal history, but in each moment going backwards, your body occupies the same spatial coordinates it did "before". In this scenario, there is no going back to meet your other self. You'd just reach that earlier point in time with your new knowledge of the future intact.

I assume that's not what you had in mind. So...

Let's say you stepped into an H.G. Wells time machine today (Jan 1) and set the destination to thirty-one days back (just to simplify the reference). Your machine travels the intervening moments, and you step out of the machine on Dec 1. To your past self, yes, the machine would suddenly appear out of "nowhere", which I haven't quite reconciled in my own mind how that would actually work. But that's as may be. Anyhooo...Now there are not just two of you, but actually three. There's your past self whose point of view you are asking about. He sees you step out of the time machine which has suddenly appeared, and also, he sees your slightly-subjectively-past self who still exists within the time machine who appears (to your past self) to be moving slowly and in reverse.

So, your Dec-1 self and your Jan-1 self have a talk, and then gets back into the time machine. Here is an important question: Do you get back into the same time machine that you traveled backwards in? The one in which "you" still exist moving backwards? Or does the time machine you stepped out of also continue separately to move forward with you in normal time? The latter is less prone to paradox, but it means that the time machine now exists twice--once with the backwards-moving you inside and once empty and ready for you to move back to the future in. When you do so, your Dec-1 now sees two of you each inside his own time machine--your earlier future-self moving backwards until he reaches Jan 1 and steps out of the machine, which presumably "disappears" at that point; and your later future-self who appears to be moving forward by veeeerrrryyyyyyy slooooowwwwwwly until it reaches Jan 1 and then begins moving at normal speed again.

I think.

LarryHart said...

...thinking a bit more on what I just wrote:

Dec-1 [you] now sees two of you each inside his own time machine--your earlier future-self moving backwards until he reaches Jan 1 and steps out of the machine, which presumably "disappears" at that point


Actually, as Dec-1 self ages normally through the month, "he" would eventually become the one who steps into the machine on Jan 1. As the moment approaches, he would see his future self moving backwards, about to step (backwards) out of the machine at the same time that he himself is walking forwards into the machine. At some point, the two would become the same person.

Again...I think.

LarryHart said...

Dr Brin in the main post:

the One Timeline Loop OTL -- betrays every single moment of joy we got from Star Trek TOS and The Next Generation and Voyager... because if that's the case, then J.J. has simply wiped every one of those adventures away and said "never mind." Indeed, does anything Chris Pine's Kirk does really matter, if the next time traveler will simply erase all his life and deeds? In fact, what would the New Kirk do with a time machine, except go back, save his dad and restore the Shatnerian timeline?


It's been so long I forget now which movie I'm thinking of, although I'm pretty sure it was "First Contact". But, one of those time-travel movies began with the gratuitous plot thread of Captain Picard receiving word that his brother and nephew were both dead. I took that personally as a kick in the balls to the hopeful ending of the episode in which those characters appeared--the young boy looking wistfully up at the stars.

In any case, Picard later is faced with a mission which specifically involves taking the Enterprise back in time to alter the past. Aha!, I expected, while back there, he will also manage to change something that prevents the needless, gratuitous deaths of his loved ones. I waited through the whole movie for that surprise ending. But no, not only doesn't he do that, but nothing in the plot or dialogue indicates that the thought even crossed his mind! Or that it crossed the minds of the writers of the movie.

As Hamilton would have it, What was it all for?

Or as Hamilton could be slightly mangled to say:

Captain, we studied, and we fought, and we killed
For the notion of a timeline that we now get to build.
For once in your life, take a stand with pride!
I don't understand how you stand to the side.



Alfred Differ said...

@LarryHart: Without trying to cast a shadow over your father, I would argue your brother is just better at loving his wife. My mother had a thing about diminutive names too that also included shortenings that didn't sound like a child's name. I dared not shorten mine until I left home and even now part of me clings to the full name. (Al is less formal than Alfred, so at work it can be politically useful to swap for the short one. Anyone using it, though, gets treated a particular way.)

Also without intending to pick on your father, there is also the fact that a person who loves you is extremely well equipped to push your buttons when you annoy them. Many years after I left home, I was finally able to see how my father did it to my mother and visa versa. As each of them passed on, I got to talk to my siblings about this. Collectively we deciphered some of the unresolved issues between them. I would argue that each of us manifested our copies of them and compared and contrasted them. One of my sisters is a lot like my mother and it was her copy of her that proved to be most accurate at the end.

Three cheers for your brother's demonstration of how to love his wife correctly. 8)

Alfred Differ said...

@LarryHart: I am going to try that trick with my wife next time we are out in the wild. She is already an identical twin, so there should be some amusement to be had with her family. 8)

I don't remember when I learned it, but I do recall learning to see long panels as a span of time. Even small panels with a lot of dialog have to be as this allows the artist to draw dialog related facial expressions in the same frame that wouldn't naturally occurring if simultaneity is expected. I have little doubt our brains do this for us to as there is evidence we reorder an observed sequence of events in our memory to match what we know must have been true of the events. We don't have the physiological equipment we'd need to take snapshot images due to nervous system time lags.


The entropic force idea is even weirder. Imagine arranging a set of electric charges in a room where there is a metal covered ball hanging from a string in the center. The surface charges on the ball will shift around as needed to turn the surface into an equipotential surface. Move one charge in the room, and the image of it on the ball moves. The information that describes the arrangement in the room is encoded on the ball's surface, right? If all the room charges started on the ball's surface, the net charge in the room would null out, but we could turn our perception inside out by asking what a flat-lander living on the ball would think was happening. We could construct a theory that explained the forces in the room in terms of information on the surface of the ball. (Any theory working with 'information' is a lot like thermodynamics where entropy represents information.)

For gravity, you have to start with a space-time grid-ed room. The analogy of the 'surface' could be any 3-D cut. It could even be our backward facing light cone where time doesn't mean much of anything because intervals between events on the cone have null lengths. No length means no ticking of the clocks. What happens to time-travel concepts when we turn things inside-out and ask what the 'flat-lander' would think? In this case, the flat-land critters would have to be made of light. 8)

Paul451 said...

Re: Time travel. (First post of three, bear with me.)

Probably worth pointing out that "real" time travel, the kind that might possibly be allowed by general relativity, doesn't involve a time machine in the sense of The Time Machine, or Back To The Future, or Doctor Who. There can be no "time machine" that itself travels through time, instead it must be a rift in time through which you pass. You therefore cannot travel back before the machine was turned on, or after it was turned off. Each "run" is the entire length of timeline through which you can travel.

For example: You might create a wormhole where the two mouths exist at different times. (There are other versions but they don't exactly get simpler. One requires the entire universe to be rotating.)

You create a temporal wormhole by first creating a regular spatial wormhole, a single volume of space split into two location by the application of negative energy. (As you do.)

You then take one end and accelerate it relativistically for a period of time, then bring the two ends back together. The relativistically accelerated wormhole mouth aged more slowly than the one left at home.

But...

...because of the way wormholes work in GR, the two ends of the wormhole remain connected to their same-age counterpart. So even though you (and the machinery sustaining the wormholes) are standing right there in the same room, the two wormhole mouths in front of you no longer connect directly to each other. The relativistically accelerated wormhole mouth connects to the stay-at-home mouth when it was the same age. Which is back in your past. The older stay-at-home wormhole mouth is connected to the equivalent aged version of the relativistically accelerated end. Which is in your future.

You can step through the younger end and go back in time, or through the older end and go forward. You will travel a fixed amount of time forward/back with each cycle, the "temporal length" of the wormhole, but you can just step across to the other end and repeat the process as many times as you want, thus travelling as far forward or back in time as you wish...

...with the limit that at some point you will step through the younger end, step out the older end in the past and there won't be a younger end in the room any more. You can't go any further. You've gone back to before the younger end was brought back from its relativistic journey.

Likewise, when stepping forward, you will at some point step into the older end, step out of the younger end in the future and discover the older end is no longer working. You've reached the point where the wormhole was/will-be shut down in the near future.

You cannot travel to before it existed, or to after it stops. But within its history of operation, you can travel from beginning to end as much as you wish.

---

Note that this kind of time travel can't really be compatible with "multiple time-lines" type explanations. The two ends of the wormhole are directly connected; under general relativity, they are actually the same volume of space. They aren't "gateways" or the usually Hollywood sci-fi versions of "wormholes". There is a single volume of space that exists in two places, and at two times. There aren't "two ends", as I've described, there's one end in two places.

---

And apparently all possible FTL schemes can be used as time machines. It's built into the nature of FTL under general relativity.

Paul451 said...

You can still use this "time machine" to create a grandfather paradox.

Imagine you have a desktop experiment. On one side of the desk is a laser. The laser can be momentarily disabled by a photodiode trigger on the other side of the desk. Shine a light on the trigger and the laser shuts off until you darken the trigger again.

So... Shine the laser into a coil of fibre-optic filament, point the other end of the filament at the photo-trigger. When you turn on the laser, the beginning of the beam goes through the filament and shines on the trigger, which turns the laser off. The end of the beam travels down the filament until it reaches the trigger, then in the absence of signal, the trigger releases, the laser comes on again and the process repeats, over and over and over.

Hence the laser blinks on and off, with a period that reflects the time it takes the signal to pass down the length of fibre-optic filament. Longer filament, longer period.

Is that clear? Hopefully I've explained that well enough.

So we create our wormhole, we accelerate one end so that the two ends are just 1 microsecond apart in time. That's possible even for us, it doesn't require travelling close to the speed of light.

We replace the fibre-optic filament in our desktop experiment with our two wormhole ends. The younger end goes in front of the laser, the older end in front of the photodiode. A beam of laser light fired into the younger mouth will exit the older mouth 1 microsecond in the past, turning off the laser slightly before it fires...

...so what happens when you first turn on the laser?

The beam from the laser enters the wormhole, travels back into its own past, hits the photodiode trigger before it was emitted and therefore prevents itself from being emitted. It prevents its own existence.

Or put it another way, every time you turn on the laser, a beam has already hit the trigger preventing the laser from ever turning on. Since the wormholes are directly connected, must be directly connected, with no parallel universes or multiple timelines, where did that beam come from?

Paul451 said...

There is a proposed solution to the causation paradox. Random particles will enter the younger mouth in the future and exit out of the older mouth in the past. Some of those particles from the future might still be around in the future and can pass back through the younger mouth again. At the moment a single particle travels back a second time, it creates a causation-loop that creates an infinite number of particles trying to occupy the same space and time. Which creates enough positive energy to overcome the negative energy that sustains the wormhole and thus the wormhole collapses. (Hopefully not taking the universe with it.)

If so, this effect will occur the moment the two ends of a wormhole are brought without the same light-distance as their temporal distance. Ie, if the mouths are 1 year apart in time, then as soon as they are within a light-year of each other, they will overload and fail. If they are 1 second apart, then as soon as they are within 1 light-second of each other... whoosh, fzzt!, kaput. Since photons are constantly passing through the wormhole mouths from all directions, at least one photon will be travelling in exactly the right direction to loop, and it will occur the moment such a loop is possible. In fact, it will have already been on its way.

The theory is that it must happen. Hence you can have a universe that permits FTL but self-censors time-machines.

This solution might therefore "save" FTL, not just for SF but for our actual real world future. It might actually be possible to create a system of faster than light travel, without creating a causation paradox, provided the two ends are never brought closer than their temporal "distance".

However, this method of FTL means that you have to drag the ends of the wormhole between destinations the hard way, before you can use the short-cut. Incredibly better than what we have, but still not quite as fun as "warp speed".

--

So Happy New Year, whenever it occurred in your timezone.

LarryHart said...

Paul451:

This solution might therefore "save" FTL, not just for SF but for our actual real world future. It might actually be possible to create a system of faster than light travel, without creating a causation paradox, provided the two ends are never brought closer than their temporal "distance".


My admittedly-amateur understanding is that relativity does not prohibit FTL travel, it just prohibits crossing the light barrier. Particles which have always been moving faster than light continue to do so, and in fact cannot move slower than light.

LarryHart said...

Alfred Differ:

Also without intending to pick on your father, there is also the fact that a person who loves you is extremely well equipped to push your buttons when you annoy them.


I see what you're saying, and there is reason to suspect that sort of intentional passive-aggressive exasperatingness. However, I have a hard time seeing my late father having it in him to keep up that level of consistency in the subterfuge. If he was "forgetting" on purpose about Mom not liking orange juice for breakfast, I'd expect to have seen more often when he accidentally remembered the situation correctly.

LarryHart said...

@Paul451,

Now you've got me trying to come up with a Schrodinger's Cat experiment where the fact that the cat is alive causes something which kills the cat, which therefore prevents its killing, etc, etc.

And is the live cat itself an "observer" in the sense of collapsing the waveform, whereas the dead cat is not? Inquiring minds want to know. :)


Paul SB said...

Larry & Paul451,

Thanks for checking out my daughter’s Wix site. It sounds like Wix has improved since she tried it a few years ago. In Paul451’s case, it could be that some of the problem you are having have to do with the age of your system, but so many people have older systems, you would hope they would be able to make a system that would maintain compatibility for some time. I suppose you get what you pay for…

Larry, if you want to post something on a Wix site, my daughter said it is relatively easy. It took her about half a day to make that site, which is a lot less than other hosts she has tried. However, she tried to add navigation arrows and they didn’t work (sorry Paul451!). Sounds real glitchy.

Paul SB said...

Alfred,

On your copying analogy, maybe when you used the term “mental model” it made more sense. I can imagine people thinking you mean that pieces of the brain twist into the shape of a person or something like that. The structural changes you are talking about are still at a microscopic level – they are about oligodendrocytes reaching out and wrapping myelin sheaths around chains of neurons like insulation around wires, making semi-permanent pathways through the more obvious structures (layers, lobes, gyri & sulci).

“…but the hormones/neurotransmitters certainly impact us functionally.”
It is the use of synapses, which results in the release of neurotransmitters, that leads to growing the myelin sheaths, so the neurotransmitters impact both structurally and functionally.

Larry said,
“I wasn't exactly equating lust with love, but there are times when what I'm trying to do with a lover is more "consume" than "copy". And yet, I'm definitely feeling love at the time.”
I assume by consume you don’t mean it in the digestive sense, exactly. :] The human brain does make a direct connection between love and lust though. If you are mating with a person who you care about and would want to spend more of your life with than just one nite, after the dopamine high of orgasm your brain will release a much longer lasting though less intense burst of oxytocin, which creates the sensation known as afterglow. That sensation basically makes you want to be with that one mate for a good, long time – romantic love. Oxytocin by itself is love (like you love your grandparents, your pets, your favorite books), dopamine by itself is arousal (which can mean sexual, but could also mean rich foods, domination over other people), the two together make romantic love.

Paul SB said...

Paul451 again,

“The initial high levels of chemical is to give you a reason to spend enough time to structurally incorporate the other person (or animal) into your brain. (**) When familiarity reduces the dose of the chemicals, you've switched to companionate love.”
It’s both, actually. It takes around 3-4 years to build up resistance to the high dopamine release involved in orgasm. The material I have read suggests that the oxytocin bond is effectively permanent, though I find that conclusion a little questionable. Needless to say, the oxytocin bond is far more long-lasting than dopamine, so it’s the oxytocin bond that leads to life-long relationships, while people who marry for sex are usually divorced within 4 years. (This pattern is cross-culturally confirmed – see Sarah Blaffer-Hrdy’s book “Mother Nature” and just about anything by Diane Fisher, her most well known book being “The Anatomy of Love”). So the structural changes (patterns of myelination) and the neurotransmitters are essentially mutually reinforcing.

The example I brought up of a person unable to leave her home even after purchasing a very expensive ticket was from the story “Evelyn” in James Joyce’s book “Dubliners.” Of course very little was known about neurotransmitters in Joyce’s time, he was describing what he was seeing. The neuro stuff was my own extrapolation.

“In your father's case, his sense of breakfast with your mother involves himself drinking orange juice. Breakfast means your mother, and it means orange juice. The two associations become physically crossed. Therefore making your mother breakfast would involve giving her orange juice.”

If I understand this correctly, your description here sounds pretty spot on. That’s how associative memory (schemata) works. Larry’s dad could have corrected this mistake with some effort (visualization is a good way), though. But remember myelin. Humans are creatures of habit exactly because doing something over and over again grows the myelin sheath that makes an action semi-permanent. Once a pathway is myelinated, it takes concerted effort to change it.

What I don’t understand is: what is the difference between your “true love” and “real love”?

Paul SB said...

Dr. Brin said,
“Life keeps showing us the vast range of humans. It's not just the spectrum of good and evil, but also smart and stooopid.”
I tried to do a little reading in that “Survival of the Nicest” book I got some time ago, though I haven’t gotten far with it. I only see my mother once a year, and she’s going on 74, so I didn’t think I should spend my time reading. Like a lot of recent books that examine human nature, this one goes into the idea of enlightened self-interest. The stooopid ones are the ones who don’t get the idea that they do better in the long run when they are nice and make friends, as opposed to cheating people and making enemies though maybe the Grope will make a counter example). The introduction all by itself has a ton of juicy quotes.

“There is much evidence that our ancestors first had to become the friendliest apes before they got the chance to be the smartest apes as well. We owe our intelligence to our willingness to give.” (p.xiv)

A longer one:

“More than twenty-five hundred years ago, Aristotle was already postulating that a happy life kept the welfare of others in view. But the philosopher had no way to prove his speculation, which is the other reason the idea took hold that moral action can only occur at the price of self-denial. But today we have empirical research that confirms Aristotle’s conjecture. Humans who act for the benefit of other are as a rule are more content and often more healthy and successful than contemporaries who think only of their own welfare. ‘One thing I know,’ Albert Schweitzer once confessed, ‘the only ones among you who will be truly happy are those who have sought and found how to serve.’” (p.x)

Alfred Differ said...

@LarryHart: In that case, I'd argue your father had a tough to beat glitch in his ability to recall a piece of the model of her. Maybe the glitch was in making it stick in the first place, but if he wasn't surprised every time she said she didn't like orange juice, it is more likely a recall error. It's not like we all avoid suffering this on occasion (Paul SB's Dory brain idea), but a persistent one on one particular piece of a model probably says something persistent about him that interfered.

I have a heck of a time stashing new information or modding older models if I'm not sleeping properly. No surprise, of course. REM sleep is rather important. I remember vividly the time right after my sleep apnea was correctly diagnosed and I got the machine and mask I've used every night since.

My boss was puzzled that year at the change in my quarterly performance reviews. I got it in July and she wondered what I had done different to appear so different in the first half compared to the second half. Heh. It was big enough of a change to be like a different employee. In a way I was. I was finally able to bring my full self to bear on problems, schedules, and training tasks.

I suspect a lot of us who don't sleep properly show this fact in these kinds of glitches.

Alfred Differ said...

@Paul SB: I can imagine people thinking you mean that pieces of the brain twist into the shape of a person or something like that.

Heh. Goodness no. My suspicion is that if we study properly how we manage to emulate each other from what little information we receive, we will find the root brain function that consumes SO many calories and makes humans human. I suspect we will also trip across the true purpose of language. A human retina has four layers if I remember correctly and each detects and compresses a flood of information to be passed down a low-bandwidth pipe into the brain. I suspect the 'terms' in our languages are like ancient eye-spots able to perceive and signal on certain memes. This would make a higher language an augmentable detector and compressor of meanings and intents. We teach our children to grow more eye-spots as we teach them vocabulary and more advanced compression methods as we expand their grammar and syntax options.

If so, it seems we have been on a copy-improvement trajectory since our variety of hominid distinguished itself. This is why I'm such a big fan of trade. We simply can't engage in complicated trade without committing to this trajectory. Every time someone comes up with a new cheat, we have to figure out what they are thinking and doing with little information and then invent a counter move. I suspect trade does for language variation what sex does for genetic variation.

Paul SB said...

"I suspect a lot of us who don't sleep properly show this fact in these kinds of glitches."
- Oh yeah!

On the subject of memory glitches, I forgot to mention why I brought up that second, longer quote. The line about the idea that moral action can only be self-denial, vs. the idea that moral action has positive effects on both giver and recipient illustrates a theme Dr. Brin has been on about for quite some time. The first is zero-sum thinking, while the other idea is positive sum. When people do good things for each other, even when it comes at the expense of the evil do-gooder, it improves society in general, raising all boats, as it were. It also embeds us in a web of reciprocal exchange. One ethnography professor liked to say that the best place to store your left-overs is in the bellies of your neighbors. When they have left-overs, they'll store it in yours.

And that is some of the difference between smart and stoopid. Of course, you can get stupid going too far in this direction, too. If you give to people who never reciprocate, that other person becomes a parasite. But pretty much all human cultures punish those parasites - except some subcultures of this one, it seems.

Paul SB said...

Alfred,

"My suspicion is that if we study properly how we manage to emulate each other from what little information we receive, we will find the root brain function that consumes SO many calories and makes humans human. I suspect we will also trip across the true purpose of language."
We kind of already do, it was hit upon by a Russian psychologist in the 1930s named Lev Vyogotsky. It's the mechanisms of this system which the neuroscientists are slowly discovering, and, as is always the case with good science, modifying and refining the model as they discover how much more complicated it is than the original idea. Much like how we refine our mental models of one another.

"A human retina has four layers if I remember correctly and each detects and compresses a flood of information to be passed down a low-bandwidth pipe into the brain."
I taught this stuff last year, and you are right about 4 layers, but IIRC, there was one specific layer that did the job of filtering the information, so the signal the forms inside our eyes is never exactly the image that forms in our brain. It's worse than that, as there is just one tiny spot in each eye (the fovea) that has the really sensitive cone cells that see color, while most of our retinas are full of low-res b&w rod cells. What we should see is just a tiny circle of clear, color vision and everything else should be blurry black and white, but our brains don't like that and fill in with assumptions.

"Every time someone comes up with a new cheat, we have to figure out what they are thinking and doing with little information and then invent a counter move"
I remember hearing a Harvard professor say that if we want our children to become critical thinkers, teach them to play poker. The game forces them to think creatively and to deal with chance. But I know from many years of gaming (it's been so long since I played poker I don't even remember the suits) that some people just never learn and give up. Still, I would hope we could get that kind of model improvement in ways that don't end with people on Skid Row, or face down with their throats slit in a gutter. I'm with Duncan on UBI, here, even if it means some people won't learn. Many won't anyway, and when your life is at stake, what many people learn is cold-blooded ruthlessness.

Alfred Differ said...

Okay. That's a neat kind of wormhole. Even without moving one end to make it a time machine it is a neat one with no horizon.

David Brin said...

Alfred my point about re-uniting familes is that once a core nuclear family is here, it can be bountiful to those back in the old country. Remittances and visits (both ways). There is no reason those who are already lucky should be favored to be even more lucky. Indeed, the more families who have a rich american cousin, the more people in the old country who will be pro-american.

LarryHart have you considered that your mom and pop had a ritual going, re the orange juice? That it was a well-beloved way to scratch the itch of delight in a touch of mutual grouchiness?

Alfred Differ said...

@Paul SB: I'd be happy to store my left-overs in the bellies of my neighbors if I can look in their eyes and see myself reflecting back at me. Even a lowfi copy would do. Even a desire to craft one would do. Absent that, I'm more inclined to trust market mechanisms and trade with them for my left-overs. The neat thing is Adam Smith showed that both options can be positive sum.

I haven't read up on Vyogotsky enough to comment. What exposure I've had to child development comes second hand through my wife as she acquires her credential and takes all those tests you all have to take. Some of the ideas sounded downright silly to me, but I'm a rusty educator of adults. Dunning-Kruger probably comes into play for me. However, I'm specifically interested in the purpose of language as it appears in the mind and care little of how it works in the brain. As a parent, I think I'm more responsible for prepping my son's mind to function in the world. I'm inclined to trust evolution and doctors for the rest.

As an amateur astronomer, I learned to appreciate the low-res rods. I eventually acquired a telescope with fast enough optics to see M31 as slightly green, but seeing the gaps between arms directly with the side-glance technique was much more interesting. I was thinking of the layers that detect edges, motion, and slight contrast differences. One doesn't need high resolution cones to get any of that. Rods that trigger with just a few photons and have a non-linear response to cope with a flood of photons are plenty good enough most of the time. Cycling response rates for the cells involved limit the usefulness of a large pipe for the optic nerve anyway.

Poker is a good way to learn where to look for information from other people. I suspect we speak many languages large and small, conscious and unconscious, and rigid or plastic. If you want to stay off skid row, though, play it for your right to remain a fertile adult while you are young and the similar rights of your son(s) when you are older. Snip, snip. It is important to balance the pleasure with the pain. Losing a few hands doesn't compare with losing other parts. I spent my last year of HS and all my college years in Vegas. The addictive power of gambling is related to the imbalance between pleasure and pain in the experience. Yah... Good thing I'm not the boss of everyone. 8)

I don't mind if you all want to experiment with UBI, but I might object if I'm forced to participate. Doing good for others is a good positive sum strategy, but I might not agree on what the good things to do are. If I'm forced, you can bet I won't list an idea among the good ones.

Alfred Differ said...

David,

I understand your position, but I still disagree. Nuclear families are historical anomalies. I was raised in one and thought they were the best thing since sliced bread, but when my son was diagnosed on the autism spectrum, my belief crashed hard. I needed an extended family and didn't have one easily available. The productivity of my nuclear family was slashed and it took me a few years to fix that.

Through much of history, children have been raised in extended families where the adult/child ratio is much higher than in our American nuclear families. Such families are robust in ways ours are not. I know there are consequences of having non-nuclear family under the same roof, but we have an awful lot of experience coping with them.

I think you'll get your remittances flowing anyway. Not everyone in a large family will want to emigrate. I can see this in my brother's wife's family. I know money is moving across at least two borders as they aren't small or disconnected. In practice, many of them behave as if our border with Mexico is a bit of a fiction and then live where they choose. Only the risk takers have come north, though, and being pro-family requires that they be pro-each-nation as much as possible.

Deep down, I can't think of a good reason to block my brother's wife's family that wouldn't already be covered by my brother and his wife. They have opinions about who among the family are louses not to be allowed in as parasites. I suspect that a family completion rule requiring sponsorship by family members would be enough to mitigate risks while getting the people who would add value here.

Anonymous said...

1984

https://www.youtube.com/watch?v=AWaquDNvggU

Jumper said...

Few mothers divorce their children. I will leave the implications for oxytocin bonding open.

Nice visualizations by Larry. My own is that other timelines are of necessity created by time travel backwards. (On a side note, what is the least different timeline we can imagine? One less quark in the universe, or perhaps one quark displaced one Planck distance?)

But anyway, my point was that backwards and forwards time travel implies matter duplication, not just of people but of the sandwich or gold coin they carry in their pocket.

LarryHart said...

Dr Brin in the main post:

Who needs privacy? Sharing is Caring. Secrets are Lies. See the preview for The Circle, starring Emma Watson and Tom Hanks, based on the book by Dave Eggers. The novel was an exquisite exercise in the art of propaganda, in which the author gives nearly all of the speeches and lecturing advocacy to those he deems evil - those promoting transparency and openness. By hammering the reader with patronizing rants and making his protagonist deliciously stupid, he invites readers to get their hackles up against the idea that she believes... and that the author hates. I've never seen it done so well. We'll find out if the flick also uses this effective Orwellian technique.


I somehow missed (or didn't focus on) your review of "The Circle" when you first posted it in 2014. Now that I see you describe it, the technique seems to be straight out of Ayn Rand. Well, except for the fact that her heroes are the ones who make the speeches (which now that I mention it, is a pretty darned big difference).

Robert said...

I thought you might enjoy this fascinating article about Berlin and Gay Rights in Germany leading up to the Nazi control of the Germany government. It is an interesting cautionary tale and also a bit of history that has mostly vanished from the view of contemporary peoples. I know I'd never even heard a hint of this when learning about history while growing up... or in college.

Rob H.

raito said...

Re: Time travel

Looks like some might want to watch Primer. Most time travel media I see contains the usual paradox: the person who is their own grandfather or the item that was never made. I don't like those. Whichever Harry Potter movie with the time travel didn't do too badly, though.

Re: Chinese Science Fiction

I'm not finding reference to it now, but I recall prior to the first Chinese convention, someone asked a Party official why now, after all the years of labeling SF as escapist Western thought? The reply was that China was trying to figure out how to innovate (already knowing how to copy), so they sent delegations to the US. And they found that all the top innovators they interviewed had read SF since at least their teens.

And wasn't Ken Liu the one who translated the other Liu's works?

Re; Rogue One

I didn't care for it. But I'm a bit concerned with how dead actors with their faces plastered on other actors' bodies are credited. For example, The actress playing Leia got a credit, Carrie Fisher did not. I missed Tarkin's credit, but I assume it was the same. I think dual crediting is the correct choice here.

Re: Čapek

Yes, his stuff is good. Hist most famous works seem to deal with class systems quite a bit, though apparently he wasn't particularly socialist. And I find it amusing that the word robot now applies nearly exclusively to mechanical/electronic 'beings', while in R.U.R. they were created humans.

LarryHart said...

Jumper:

But anyway, my point was that backwards and forwards time travel implies matter duplication, not just of people but of the sandwich or gold coin they carry in their pocket.


Hmmmm, not so much duplication as a sort of borrowing.

On the time traveler's subjective timeline, there is no duplication. The fact that he's in two (or three or more) places at the "same time" means that that additional matter is borrowed (or maybe stolen) from the future. This is best illustrated, again, in Scott McCloud's "Understanding Comics" in a cute little strip involving a man at a restaurant who, lacking cash, borrows money from his future self by dropping a fishing line down to the comics panel below and lifting money out of his future-self's pocket. Only, by the end of the strip, when he has to pay the waiter with that money, he's reached the panel where the money is being stolen out of his pocket!

A long time ago, on another forum, I posted an argument that the seeming-paradoxes in time travel can be better understood by analogy to borrowing and spending money. If I can find that post on the "Cerebus" forum, I'll cross-post it here.

And BTW, the duplication you describe only results from backwards time-travel, right? My own personal conviction (which I'll change with evidence, but not without) is that one-way time-travel to the future (or at least something indistinguishable from it) is possible, but backwards time travel (in the sense of being able to alter the past) is not.

LarryHart said...

raito:

I'm a bit concerned with how dead actors with their faces plastered on other actors' bodies are credited. For example, The actress playing Leia got a credit, Carrie Fisher did not. I missed Tarkin's credit, but I assume it was the same. I think dual crediting is the correct choice here.


I think you are correct about Tarkin as well. And remember, Carrie Fisher wasn't dead when this movie was made, and she still doesn't get a credit. I also wonder about the implications of this technology in filmmaking going forward. Marlon Brando wanted too much money to appear in "Godfather II", so Robert DeNiro ended up as young Vito Corleone instead. What if the studio had just plastered Brando's face on top of the actor instead? The audience might have a more consistent experience. But not only does Brando get stiffed, DeNiro's career might never have taken off.

Although it doesn't seem like it, we're talking about all kinds of time travel here. :)

Jumper said...

I suspect time travel to the past is impossible too. It was a "but if, then.." thing. Not to mention materializing a human body plus whatever posited hardware into a world-line is a change of a hell of a lot of small particles, more than my proposed single-quanta change as rock-bottom minimum. Not even to mention that one quark's difference half the universe away from us is more likely. But if it's outside the light cone, irrelevant...
But anyway. If you go to the past, find yourself, change things enough so your past self no longer has a reason to time travel himself, when original you returns to a future, it's not the one you left. It's a new world-line. And now there are two of you. The original world-line "now" has a missing you who never returns. There are now two lucky pennies you've carried since childhood in your pocket as well. Not that you'll be richer: there are two of you and each of you has one.

Paul SB said...

I'm going to stay out of the time travel thing, as I'm sure I know so little about the physics of space-time my thoughts wouldn't be worth much. However, my daughter just told me that someone contacted her through that Wix site she made to let her know that they were able to see it with whatever operating system they were using. I figure I should say "Thanks!" but the person did not leave their name. If a person does a good deed, great or small, and prefers to remain anonymous, there's honor in that. So my hat's off to this anonymous anti-troll, whoever you are!

Paul451 said...

LarryHart,
"Schrodinger's Cat [...] And is the live cat itself an "observer" in the sense of collapsing the waveform, whereas the dead cat is not?"

The live cat is an observer. The dead cat's body is an observer. The box is an observer. The air inside the box is an observer. The vial of poison is an observer. The lever that breaks the vial is an observer. The radiation detector is the first and primary observer.

Schrodinger was trying to describe something that he believed couldn't happen, but which was implied by the Copenhagen Interpretation (the "observer effect"). He was asking people to think about the logical conclusion, "where does the observer end?"

Finding the limit between classical and quantum is part of the fun of modern quantum research. (Google "schrodinger's kittens", the nickname for research into how precisely the line between quantum and classical breaks down by devising devious real world nano-versions of Schroginger's thought experiment.)

[Aside: I originally wrote "the vile of poison".]

Paul451 said...

Jumper,
"If you go to the past, find yourself, change things enough so your past self no longer has a reason to time travel himself, when original you returns to a future, it's not the one you left. It's a new world-line."

That was the point of the desktop wormhole example.

Because of how the maths of wormholes works in general relativity (I mean, that's where the whole concept came from), the two ends of a wormhole are actually the same space.

A wormhole can't link two separate time-lines.

Yet the same relativistic maths says that you can create a "time machine" with a stable wormhole.

So it describes a set-up that requires a single universe, a single time-line, but also permits a temporal paradox.

Paul451 said...

LarryHart,
"My admittedly-amateur understanding is that relativity does not prohibit FTL travel, it just prohibits crossing the light barrier."

No, but it requires that all possible FTL methods can also be used as time machines. So if we assume violation of causation rules out the possibility of time machines, then it must also rule out FTL.

That's what I meant by "save". If the universe inherently self-sensors FTL when it creates a temporal loop, stopping it from working at precisely the moment when it can be used to violate causation, then FTL itself may turn out to be possible.

"in a cute little strip involving a man at a restaurant who, lacking cash, borrows money from his future self by dropping a fishing line down to the comics panel below and lifting money out of his future-self's pocket. Only, by the end of the strip, when he has to pay the waiter with that money, he's reached the panel where the money is being stolen out of his pocket!"

If I'm understanding your description correctly, the author was cleverly illustrating a "closed time-like curve", a closed loop. The banknote had no creation, it exists only inside the temporal loop, with no beginning and no end, and it somehow lasts forever and never ages or wears out.

(Think about it from the banknote's POV, how does the act of hooking the note (damaging it), folding it and stuffing it in his pocket (stressing the paper), not accumulate enough damage for the note to turn to dust in just a few million loops? Let alone an infinite number. Where in the loop is it "reset"?)

The comic actually demonstrates the flaw in your time-travel-as-finance idea by stripping it back to a dollar-for-dollar swap (thus leaving out the "growing business", it's literally the same banknote.)

LarryHart said...

Jumper,

I'm also engaging in thought experiments, some of which I'm considering for the first time. For example, I never before considered what it would look like to an observer when a backwards-traveling time machine suddenly appears at the endpoint of its travel. The discontinuity there is evidence (to me) that we're describing fantasy rather than real possibilities. Likewise, in your multiple-timeline scenario, it's not just a matter of duplicating your time-traveling self. The theory seems to be that entire universes are created at every choice. I just don't see where all of that matter and energy comes from.

Twominds said...

On time travelling: I liked the take of A. Niffenegger in 'The Time Traveler's Wife' where travelling in time is more or less involuntary, caused by a genetic disorder. Because of this, the time traveller can't take anything with him, not even his clothes. Nor can he aim with precision where he ends up. This causes interesting difficulties, both for him and his wife.

LarryHart said...

Paul451:

If I'm understanding your description correctly, the author was cleverly illustrating a "closed time-like curve", a closed loop. The banknote had no creation, it exists only inside the temporal loop, with no beginning and no end, and it somehow lasts forever and never ages or wears out.

(Think about it from the banknote's POV, how does the act of hooking the note (damaging it), folding it and stuffing it in his pocket (stressing the paper), not accumulate enough damage for the note to turn to dust in just a few million loops? Let alone an infinite number. Where in the loop is it "reset"?)


There's a minor plot device like that in the movie "Somewhere In Time" with Christopher Reeve and Jane Seymour. At the start of the movie, in 1980, elderly Elise McKenna (Seymour) hands Richard Collier (Reeve) a watch, and tells him to "Come back to me!". Later in the film, when he has traveled back to 1912 to woo the younger Elise, he gives her the watch.

That's hardly the main plot of the movie, but it does present a paradox of the type you describe, in which the watch has no beginning and no end. Except I once posited a way around that. In 1912, Richard gives Elise the watch which (unbeknownst to her) he received from her older self in 1980. Five years later, Elise accidentally loses the watch down an open sewer. Much later, say in 1975, older Elise is shopping at a bazaar in Marrakesh when she spots a watch that looks like the one from her lover which she lost as a young lady. Upon closer inspection, she realizes that this is not only a similar watch, but the same one. Out of curiosity and amazement, she buys the watch for a mere $1.50 American. That's how she has it on her when she stumbles across young Richard in 1980, and gives him the watch.

The watch's timeline then starts with wherever watches come from to its sale at the bazzar to Elise in 1975, to Richard in 1980, back with Richard and then to Elise in 1912, and then wherever it ends up after dropping into a sewer in 1917. If the watch is old enough, then it exists as two versions between 1912 and 1980, but after one of those versions goes back in time, the other one (down the sewer) becomes the only one. It's not a closed loop. It's more of a loop-the-loop.

The comic actually demonstrates the flaw in your time-travel-as-finance idea by stripping it back to a dollar-for-dollar swap (thus leaving out the "growing business", it's literally the same banknote.)


The comic is funny because of what it says about comics, not because of how time-travel actually works. To be analogous to my economic scenario, he would drop his fishing line into a pile of cash that he had made years later in his successful business, and pull out what he needed to invest in order to start that business. Since even without the seed money, there is plenty left in that future pile, there's no violation. The succeeding panels would have him starting the business and eventually raking in the cash.

What if the business failed instead? Well then there's have been no pile of cash to fish from in the first place, would there? That wasn't exactly my original point, but I wasn't trying to relate it to this comic strip either.

Anonymous said...

https://www.youtube.com/watch?v=tqo8CxSPvCU

Jumper said...

Except the multiple world lines idea has theorists a lot smarter than me taking it seriously. I don't think instant creation of universe-sized masses on-demand is quite what they are positing. They have all been here since the beginning. True that's a big infinity.

LarryHart said...

Not exactly time travel, but looking forward in time a bit...

Only 1,480 days until inauguration day in 2020.

Just sayin'

David Brin said...

Does the anonymous sniper actually think we're visiting any of his rants? Maybe one of you might report say each weekend on what the crap was?

LarryHart said...

@Dr Brin,

I have no interest in risking infection by clicking on those links, nor am I curious enough to feel like I'm missing anything. Your blog and all, of course, but in my humble opinion, the last thing we want to do here is talk about them as if we care in any way.

BTW, you have the distinct honor of having elicited from me as responses the only posts I've made so far in 2017 which do not involve time travel. I was almost going to make it a New Years resolution to only talk about time travel this year. But then, I don't usually make New Years resolutions at all, let alone keep them.

I do give things up for Lent, though, even though I'm not required to.

Paul SB said...

Reminds me a little of the Robert Heinlein story "By His Bootstraps" in which a character goes into the future and gets a notebook explaining the language of the people "then." Later the notebook starts to get worn out and he copies it over in a new notebook. At some point in the story he realizes that the person he got the notebook from was a future incarnation of himself, and the notebook he was copying was being created as he copied it. This is the kind of stuff that gives people headaches. Maybe it's partly to blame for some people's distaste for science. When physicists come up with things that are so far beyond our normal experience, and most people can't understand without a whole lot of effort, they are left with taking it on faith or rejecting it as nonsensical. Since religion is the thing we are trained to take on faith, believing scientists who seem to be talking nonsense just doesn't mesh with our schema.

I said I wasn't going to talk about time travel, but the nostalgia urge...

Larry, on New Year's resolutions, ages ago my resolution was to never make a New Year's resolution again, and that is the one resolution I have been able to stick to.

Jumper said...

Anon is in a group of pizza-gate obsessed people. Many psychologists would probably say that obsessing about child sexual abuse 24-7 suggests projection: something in their own minds gets projected into scenarios where it doesn't actually exist. They may be fascinated a little too much.
I find this deeply creepy.

The YouTube links are useful to students of madness only.

LarryHart said...

I said:

To be analogous to my economic scenario, he would drop his fishing line into a pile of cash that he had made years later in his successful business, and pull out what he needed to invest in order to start that business. Since even without the seed money, there is plenty left in that future pile, there's no violation. The succeeding panels would have him starting the business and eventually raking in the cash.


And my point back in 2005 was that this really is how borrowing money for investment actually works. Sort of.

Let's first examine the "happy path" in which everything goes right. You borrow $100,000 from a venture capitalist to use in setting up your business. Your business kicks ass, and in five years or so you're sitting on several million dollars worth of business and paying yourself a half-mil every year. As part of the business expense, you've paid back the initial loan, so your business is not in debt.

How is that functionally different from having dropped a fishing line into your cash drawer five years later, picking $100,000 out of the drawer, and using that cash to start your business? I mean, sure, your drawer is $100,000 short, but that's just the $100,000 you'd have otherwise used to pay back the loan that you now don't need. In fact, it appears you're actually saving money on the interest. The venture capitalist is short the interest you would have paid him, but he's had the capital to use elsewhere, so I haven't quite figured out the ramifications of that part. Let it stand for now.

Once you've paid back the loan, you might as well have borrowed from the future, and then paid it back out of your subsequent profits. There is no discernible difference between that and what actually does happen when you borrow money and then pay it back.

When we talk about time travel paradoxes, we're asking the equivalent of "What happens if your business isn't profitable enough to pay off the loan?" Well, what does happen in that real-life situation? There are many different possible scenarios around who ends up losing money they didn't expect to lose, but none of them involve universe-altering paradoxes or metaphysical solutions or multiple timelines in which you're successful in one but a failure in another. Depending on how the borrowing is structured, it's pretty clear which money gets spent where and who is left holding the bag if profits fail to materialize.

I'm asserting that the same sort of sorting out would occur if you "borrowed money from the future" which alters history in such a way that that money isn't there. Or more in our line of inquiry--if money from the future travels to the past and alters it in a way which prevents its coming into being. Given the initial conditions and constraints of the experiment, the laws of physics will determine how the future plays out in a particular scenario. Follow the money. :)

LarryHart said...

Paul SB:

Larry, on New Year's resolutions, ages ago my resolution was to never make a New Year's resolution again, and that is the one resolution I have been able to stick to.


Heh. Sounds like the year I gave up broccoli for Lent.

But lest you think I always make it so easy, in the past I've given up things that really make a challenge. One year, I gave up elevators, and my grandmother was on the 25th floor of a high rise. The hardest one was the year I gave up comic books. I'm never doing that again.

Jumper said...

If future guy's timeline continues, he's just been ripped off. The banksters hire an enforcer who beats your future self up. Thanks, bro!

David Brin said...

Terrific stuff. I start the year with the smartest community on the web.

onward
onward

Jonathan Sills said...

Did no one bring up Niven's First Law of Time Travel, or did I just miss it?

The law states that in any universe that permits both travel backward in time and changing the past, time travel will never be invented. Eventually, the timeline will become so fouled up by people trying to change one thing only to find it affects untold other things, that someone will decide the only solution is to kill the inventor of the device before he can invent it, thus eliminating time travel altogether.

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