Searching the Internet for evidence of time travelers | Hacker News Reader

Searching the Internet for evidence of time travelers

arxiv.org

210 pointsColinWright147 comments

This is interesting, but these methods don't strike me as really viable. The Twitter outreach was specifically targeted at the cooperation of Twitter-using time travelers, and while Pope Francis might or might not be historically significant enough to warrant prescient mentioning, I'm sure comet ISON is not. The assumption is also (and maybe it has to be) that time travelers would blurp out important prescient information - however, I don't think that holds true if they were either well disciplined or engaged in historical research - which would mean they know little more (if anything) about our immediate future than we do.

I'm obviously not advocating time travelers are present (I would think with the certain prospect of leaving your time line in order to create another one, the proposition of time travel seems akin to a one-way change in universes that doesn't sound very inviting), but it's definitely fun to speculate about. Realistically, one would also have to take into account the fact that, by mere virtue of being present, a time traveler will change the course of history in the long run.

A more thorough effort could center on large-scale automated data mining for prescient terms on the internet. Of course, there would be many false positives, but as a side effect we could learn more about the epidemiology of ideas even if we don't discover time travelers. It seems to me that a disciplined time traveler would not purposefully drop historically significant hints - however, if they are from a future and culture close enough to our own, they might still reveal themselves inadvertently through idiosyncratic phrases and reference to concepts that are from the future. Hand-picked phrases are not enough to discover this, it would have to be large-scale AI-supported text mining.

> Twitter-using time travelers

If I were a time traveller I probably wouldn't use any of the social networks that are popular for non-time-travellers. Firstly managing so many social network accounts to keep up with the latest fashions would be a right pain (imagine having to change your profile picture on all of them...), but also their 'timeline' view would be completely different to my relative timeline.

I'd assume the network format would be distributed, running on something akin to a phone that you keep on you at all times. Whenever you make a post it records your relative 'life time', or just increments an id, so posts are always ordered in your relative timeframe. When you meet someone it would sync up with their account - I'm not quite sure how that would work though. The issue is you could post something about them publicly that hasn't happened yet in their timeframe (that could be embarrassing). Private messages are even worse...

(N.b. I should probably patent this idea for when time travel is invented)

Nice idea. Although the user-base of time travellers might be a bit limited. I would suggest broadening your product to include the soon-to-be emerging high relativistic speed and FTL travel sectors. Part of the process of friending someone could be to indicate how your respective light-cones intersect, for example.

If your network is ad-supported then there might be extra complications in temporally localising the ad content so that it doesn't induce the wrong kind of causality violations. You might want to give that some thought, now or in the future.

Disclosure: I'm not a VC in this timeline.

"Hand-picked phrases are not be enough to discover this," "... are not be..." - AHA! We've GOT YOU! Now, tell me my future! ;-)

Dammit, not again ;)

> a time traveler "will" change the course of history in the long run

Going by the current recognized (theoretically possible) understanding of time travel based on Einstein's theory of special relativity[0] it would be only possible to travel in the future (near or distant based on technology that is not yet available).

Travel back would not be possible. And for the entire period of the time jumped the person(s) would not be present.

Based on this theory alone the time travelers would not be able to change history.

Depending on how far they travel I doubt they'd be able to change the future either.

[0] https://news.ycombinator.com/item?id=6999933

Isn't the issue here that they are describing the methods through which they are trying to determine time travel. In effect, telling anyone in the future exactly what not to do.

Let's also assume that somebody had a reason to travel into the past, say to kill Hitler. Our timeline would record that an Austrian artist was murdered in the 1920s. We would not consider this historically significant.

I think time travel is inherently very difficult to detect. Even if a time traveller 'dropped' tech. This tech would be recoverable by popping back in time and recovering it.

"...say to kill Hitler."

Everybody kills Hitler on their first trip. http://www.abyssapexzine.com/wikihistory/

Thanks for that link, i haven't laughed this hard in ages

Well, then starting to read at http://tvtropes.org/pmwiki/pmwiki.php/Main/HitlersTimeTravel... may be dangerous to your health.

It's beautiful for how it captures the essence of all message board fights.

Why just Hitler? Stalin and Mao were arguably equally as bad:

http://necrometrics.com/tyrants.htm

And there are monsters like Leopold II of Belgium (possible victims in the range 2-15 million) who hardly anyone remembers:

http://en.wikipedia.org/wiki/Leopold_II_of_Belgium#Exploitat...

Actually, as hardly anyone remembers Leopold II maybe he is the ideal target.... :-|

[NB I eventually remembered that I'm against the death penalty - so what I am actually in favor of is apprehending the relevant individuals and bringing them back to face trial by the appropriate authorities. Although I admit there would be a distinct temptation to do a Cheradenine Zakalwe with Vasili Blokhin:

http://en.wikipedia.org/wiki/Vasili_Blokhin

Where was the Grey Area when we needed it!]

Killing Stalin without killing Hitler might not be the best idea, considering the vital role Russia played in the defeat of the nazis. And maybe Leopold II gets overlooked by time travelers exactly because they also don't remember him.

(Good of you to mention Leopold II, though. Also note Henry Morton Stanley's role in that despicable piece of genocide.)

There is a view that General Winter managed very well by himself.

Actually, the H man and those guys don't make the cut. The ones deserving of time-travel assassination have already been dealt with. Hence we don't know of them.

Exactly. If we are going to hypothesize about time travelers then we have to accept that any significant reason to time travel has already happened. Futhermore it has happened more times than we are aware of to create our specific timeline.

Maybe Hitler was a time traveler himself.

http://mark.laabs.net/alternate-theory-for-obamas-nobel-priz...

I am wondering, that things like killing someone historically significant won't be done unless there is extinction level threat from that individual.

Other wise the people in the future would decide to just let it play.

7000 personally executed over 28 consecutive nights, through a shot in the base of the skull while wearing a leather apron, gloves and hood, 300 a night for 10 hours each night, one every 3 minutes?

That's some character...

It takes a certain kind of monster to order the execution of 7000 officer prisoners of war. It takes another kind to carry it out personally with a collection of pistols brought in especially for the job.

I can recommend (if that is the correct term) the book "Stalin: The Court of the Red Tsar" for a chilling description of the leadership of the Soviet Union from the early 30s until Stalin's death:

http://www.amazon.co.uk/Stalin-The-Court-Red-Tsar/dp/0753817...

There's also an excellent 2-part CSPAN "Book Notes" with the author:

http://www.c-spanvideo.org/program/Tsa

Agreed! It is next to impossible to understand soviet Russia without knowing what is covered in that book. It completely changed my view of the whole Bolshevik experiment, especially Stalin's role. What had been a mystery to me became much clearer.

I can't wrap my head around this. I'm not even sure he went insane because of the unhumanity of such an act or because he was out of the system.

Wouldn't it be highly probable that the untimely death of any of those men would cause almost everyone born after the war to cease existing?

Would it not be a much better idea to kill Columbus, and prevent the 'discovery' of the Americas, thereby saving the population of nearly two whole continents? Can't be much more efficient with your time travel than that I reckon.

edit: Just read the interesting link you posted to 20th centuries bloodiest tyrants. I wonder why Johnson and Nixon are not in the third list, bloody tyrants who killed over 400.000 innocent civilians in the Vietnam war using horrible chemical warfare.

Columbus was a particularly unsavoury individual whose instinct was to sell the Taino natives he encountered as slaves, but it is difficult to imagine a scenario where the inevitable large scale contact between the Old and the New Worlds would not have resulted in calamitous declines in the native population of the Americas who had no resistance to smallpox and other Old World pathogens, no matter the nature of the intial contact. Even without Columbus, it would have been a matter of time before the Europeans found out about the Americas.

Because of Columbus I and most of Latin Americans are born, most of us are a mix of European and Native Americans. If all of that population was really killed, there would be just white people in the spanish and portuguese territories.

Ignoring the rest of your comment… how would this kill you all?

My point was that the population was not exterminated in this side of America, the proof is us (Latin Americans), for example Mexico with 90% of its population being "mestizo" (european/native american) with variations of 70%/30% 50%/50% 30%/70%

Have you read "Pastwatch: The Redemption of Christopher Columbus" by Orson Scott Card? It get's a little weirdly preachy, but the idea that Columbus really is the fulcrum about which the fate of the Americas tips, and that if you could go back and get him to think of the locals as actual people and not savages, things could work out pretty good.

If you don't mind changing history, it might be better just to go back in time and give the natives small pox vaccine. Contact was inevitable.

Hell if you are going to do that there are probably countless other things you can do to improve history.

If done even slightly wrong this would be easily detected.

You need to find someone who would have been worse than any of these folks but was killed when very young.

It's historically more romantic to kill Hitler than any other dictator.

"Why just Hitler? Stalin and Mao were arguably equally as bad:"

Read the story. This is covered. Quite well, IMHO.

Jesus Christ! After reading that wiki on Leopoldo I am personally signed up to be the traveller to go back and murder that SOB with impunity!

See also [0] for explanation why no one ever succeeded.

[0] - http://www.viruscomix.com/page382.html

thank you. I was thinking about this fantastic story the other day and I was wondering if I'll ever find it again. Bookmarked.

you are assuming time travelers change history, but it's different if you subscribe to the idea that you can't change past because in fact you did not change the past.

Then you can detect people saying stuff about the future, or possibly attempting to kill hitler while failing miserably.

> Let's also assume that somebody had a reason to travel into the past, say to kill Hitler. Our timeline would record that an Austrian artist was murdered in the 1920s.

This would prevent World War 2 and the associated advances in technology, possibly including those leading to the time travel being possible in the first place.

You could also imagine the converse, where someone from the future brings back all scientific knowledge, thus reducing the time it takes scientists of the past to invent time travel, which in turn leads to that person bringing back all scientific knowledge sooner, perpetuating onwards until massive amounts of knowledge are acquired in small amounts of time. Such is the nature of the grandfather paradox.

Given that people cannot learn infinitely fast and progress needs time to happen, there will be a point of equilibrium.

And have you thought about how many potential hitlers were pruned in the WW2 ... every one that died in the conflict could be much worse than him. So maybe Hitler was a historical fuse. A maniac just 20 years later could have destroyed humanity. Dead serious here, assume that nuclear weapons were available from day1.

So maybe there was time travel manipulation to ensure WWII so that humanity could survive.

Now you're just messing with my mind.

Perhaps the WW2 in our timeline is the least worst outcome.... :-|

e.g. What if the Normandy landings had failed? The Nazis would still have been defeated by the Soviets but the whole of Europe north of the Alps could have been occupied by the Soviets, perhaps making a far worse later nuclear conflict much more likely.

I think Stephen Fry wrote an alternative history book based on that premise.

Sounds like a plausible sci-fi story!

This makes no sense... here is why:

"Hey Bob, you idiot! Someone found you by a stupid tweet you made. Then they posted a research paper online and now everyone knows about time travelers. Go back and fix it."

"Done"

The very act of publishing the results of this study could have caused the results to be changed, thus showing a non-positive match...

That would be a great (yet unsatisfying) twist for the end of a low budget sci-fi movie.

I'm not sure why time travellers from the future would bother to leave prescient messages on the net. What's the motivation? Something like graffiti artists tagging difficult locations?

What I can see them (hypothetically) doing is manipulating present-day financial markets by exploiting their knowledge of future events (e.g. sudden commodity shortages or unexpected mineral discoveries) to increase their wealth. Even small manipulations would produce large downstream gains due to compound interest.

So perhaps market data is a place to look for abnormalities - particularly in existing systems that look for signs of insider trading, or investment accounts/trusts that are untouched over very long periods of time. Of course, such data is usually protected and inaccessible anyway.

Yes, I would probably go back to 2009 and mine bitcoins (or fill captchas for 5 BTC a piece..) with a CPU..

Good point. All the early bitcoin miners are clearly suspect. And Satoshi Nakamoto's sudden appearance and then disappearance now makes total sense.

Combining time travel and computation has interesting results:

http://www.frc.ri.cmu.edu/~hpm/project.archive/general.artic...

Totally serious question: If I go back to 1990, can I distribute a current version of emacs? The toolchain to build the current source tree won't exist for a while.

Why not? Any computer program is just a very large number. Even thought the emacs build process that calculates the large number corresponding to the current version of emacs hadn't been performed in 1990, the number itself "existed" back then as the outcome of any number of other possible computations.

On the other hand, you might have problems with dll dependencies.

Or maybe Emacs can't run in a home machine of 1990

Remember? Eight Megs And Constantly Swapping

I assume @danielweber was asking whether it was possible in principle - as in, can information exist before it is created.

My remark about dlls was an attempt at humour, not a comment on practicalities.

Oh, youre running a binary that uses CPU extensions or dependent on a kernel that doesn't exist yet? Enjoy your segfaults.

GCC stage1 is deliberately written in K&R C so that you can do this kind of bootstrapping. You need a few unix tools (e.g. make - but again, a version from 1990 should work, find yourself a solaris machine or something); I don't remember exactly what emacs depends on, but it should be fine. Getting a modern environment on old unix boxes (or under windows SUA, whose unix stuff is old enough that it comes with X11R5) is fun and usually requires a bit of fiddling but nothing too serious.

If time travel was possible there would be a lot of ways to make money more efficiently than with bitcoins.

You are all assuming that money is still in use in the future.

I'd say the very fact that most Bitcoins weren't created in the first few hours is a good indicator that there are no time travellers. Or if travellers do exist, access to time travel has been restricted, or perhaps Bitcoins and possibly even currency is not of interest in the future.

In fact, time travel could render investments obsolete.

There, you just found proof that Bitcoin is going to collapse in the future!

I think the idea is that they would go back to stop the 9/11 attacks, and then on the day prior would look up "flight 11, flight 175, flight 77, flight 93" in google (maybe in separate searches) to see exactly when/where they took off. They wouldn't mean to leave the clue, but no one should have any reason to connect those 4 flights together until the next day.

I guess that would be one motivation. But wouldn't they just do the searches in their present (our future) before travelling back to 2001?

And if they did prevent 9/11 then nobody would connect the searches anyway, because there'd be nothing to associate them.

On a tangentially related note, the tabletop roleplaying game Continuum has, IMO, the most interesting description of time travel and a time travellers community.

The premise is simple. What is the most logical thing for the first time traveller to do? He would travel to the future to get his hands on the most advanced time machine possible. In the end, the best is the human mind. They time (and space) travel with a simple thought.

It has a single "timeline", i.e. changing something in the past doesn't "split the timeline" but creates a paradox, that translates to "frag" on all people related to the changed action. This makes people want to correct these paradoxes.

Example, I go back in time and kill Hitler. It frags a LOT of people. The good guys want to correct the frag. They could go back in my timeline and prevent me from doing it, fragging me. If they don't want to frag me, they could switch Hitler with a Robot or something. I don't get fragged because still I shot something I though was Hitler, yet Hitler remains alive.

Wouldn't we as well need a counterpart to "frag" such as "pop" for all the people saved/born due to the change? Then if the "good guys" corrected the original "frags" those "popped" people would be re-"fragged" which would cause a split group of "good guys" to attempt to "correct" the previously "corrected" history?

Not really. It's cosmology is weird.

The universe is kind of a mutable thing full of "sentient force" (it's time travellers). When a paradox is formed, it's defense mechanism kicks in to eliminate the paradox. That defense mechanism is the good guys (the continuum).

Frag is associated with what you KNOW. Information is usefull but very dangerous. Imagine this, I go to Auschwitz and see all that horror. I decide to kill Hitler and succeed. I just fragged myself, because I know I killed Hitler (therefore, the Holocaust never happened) yet I saw/know what happened if he were alive. Frag is like being "out of sync" with the universe. If I don't feel frag, it means the good guys intervened, and nullified my action. Of course, as punishment they would probably frag me in another way.

Why do they prevent the killing of Hitler? Because they and their frieds may have/will have seen the consequences of Hitler's actions so it's in their interest to prevent the paradox.

Practically, it doesn't matter what really happened, just that it happened as remembered by the coninuum, and that the consequences remain the same. Another example, by some means, JFK's father is sterile. He can't concieve JFK This is a problem as JFK is known to exist. The continuum may stealthily inseminate JFK's mother for him to be born. In the grand scheme, it may be even impossible to know if JFK's was always sterile or if some outside force made him sterile. The universe must BE as it is remembered.

Higher level continuum members start realizing that, in fact, free will does not exist. You just have to do what you have to do, and have fu doing it. (This is also the main focus of disagreement with the bad guys.)

I like the book's example of simple frag with the beer.

So the setup is that you and your time travelling buddy are watching the big Sportsball match on TV in both of your relative presents.

You want a beer so you go to the fridge and there isn't any. So you jump Downstream a couple of minutes, grab a brew and jumps up. Uh oh, don't drink and Span because you just fragged your friend as you are both drinking the same beer.

Your friend is naturally peeved and tells you to fix it. So, what you do is:

* Buy a pack of the same brand of beer and put it in the fridge

* Put a note on one of the bottles telling yourself and your friend not to touch it

* Span (Jump) Upstream a few hours so it's cold then jump back to just after you took the beer from the fridge yourself and put the new beer (the one that was cooling in the present -> future) in so your friend can grab it when he wants a beer.

* You also have to not run into yourself so you jump back up to after the point where you left for the future so as punisment you miss the big sportspile. However all is well because you friend just fills you in regularly and you both enjoy your tasty beverages.

Heh, reminds me of John Titor, the time traveler from the future who was working on the Year 2038 problem: http://www.abovetopsecret.com/forum/thread61544/pg1

I never thought I'd see ATS referenced on HN...

I'm about to go back in time. If I succeed, the silicon transistor gets invented in 1954 and Christmas goes to happen in the winter (northern hemisphere).

Wait ... how did you do that?!

How could I know? It was the me from the other timeline.

I don't know why HN shows comments from the alternate timelines, I'd file a bug for that if they had a bugtracker.

There's a relevant Mitchell and Web scetch. Someone travels back in time and meets Faraday. Faraday asks a bunch of questions, none of which can be answered because the traveller is just an everyday person who has little clue about how things work.

Armstrong and Miller actually: http://m.youtube.com/watch?v=6c2kyNJ3Omo

Whoops, thanks for the correction.

I did wonder why I couldn't find the clip in YouTube.

You may have been thinking of this sketch: http://www.youtube.com/watch?v=oa_hiLXLbTc Where one guy proposes a modern idea but it makes no sense to people of the past. I think this is one of a 2 or 3 such sketches.

There's a slightly silly-but-entertaining film in which an aircraft carrier goes back in time. The spoiler of the film is that one man who is left behind in time becomes absurdly rich by becoming a pioneering "inventor".

So we should look for absurdly rich people who have made dozens of inventions.

http://www.imdb.com/title/tt0080736/

This is a great lazy Friday night film.

Right. Just make sure you don't read my spoiler comment first :-(

I believe that there was a similar premise in a series of Star Trek: Voyager episodes, where a businessman steals a time traveler's technology and uses it to bootstrap the modern computer industry.

You could also just invest in companies that you know will succeed rather than inventing anything. That's harder to look for.

Looks like an Ig Nobel prize winner to me.

> Although these negative results do not disprove time travel, given the great reach of the Internet, this search is perhaps the most comprehensive to date.

PDF of paper in case it wasn't obvious:

http://arxiv.org/pdf/1312.7128v1.pdf

There is no such thing as time travel. There is only teleportation. Because you have to have 4(or 10) fixed coordinates to move. Just time travel means you will be in vacuum, rock or middle of a star the moment you arrive.

Since we already found the higgs I think the next line of research should be what exactly gives a particle "the where".

Doesn't relativity say there is no such thing as fixed coordinates? That it all depends on frame of reference.

That point is often brought up. But we don't really know how a time-machine could potentially work, so why is teleportation a necessity? If you want to travel to the future you would abuse time delation. While all means to do so pose certain problems none of them involve teleportation. If traveling to the past would work in a similar way the time-machine would move trough every moment until it reaches its destination. If it never has to leave earth or its orbit to do so it would always be affected by gravity and as such end up where you want it to.

Ever so slightly disappointed at the complete lack of mention of Steins;Gate (http://en.wikipedia.org/wiki/Steins;Gate) in the paper. Interesting read all the same :)

And no John Titor!

http://en.wikipedia.org/wiki/John_Titor

With a cursory look, I couldn't figure out if this was serious. Assuming it is, I'm convinced that Time Travel doesn't exist because casinos and sports betting exist, and casinos would go broke if time travel existed. (Unless you altered time so much travelling in time that you altered everything in the future)

If we consider that multiple "time lines" can exist in parallel (multiverses perhaps?), and if we consider that changing an event is the equivalent of making a new decision and branching into a new multiverse, then it stands to reason that at least one universe still exists where casinos and sports betting have not gone broke. And it must be this one.

This seems less likely than time travel is impossible, no?

If time travel is possible at all, we'd eventually discover and use it. I wonder if this means that we'll destroy our civilization before becoming able to use time travel (seems more likely than time travel being impossible to achieve within thousands of years from now).

One could also posit an Anthropic Principle of time travel: the fact that we still exist means that our universe is among the tiny subset of potential multiverses in which time travel is not discovered, or whose use is sufficiently constrained so as to not result in destruction or paradox.

Or that time travel is discovered so far into the future that change in our time would have un-calculable consequences even for that advanced society.

Or that they have discovered immortality and view us as a subspecies like we would neanderthals.

Larry Niven phrased it thusly:

> If the universe of discourse permits the possibility of time travel and of changing the past, then no time machine will be invented in that universe.

http://en.wikipedia.org/wiki/Niven's_laws

If you are interested in time travel: I saw the movie "About Time" last night and it was both awesome and romantic. Perfect date movie for the geek/non-geek couple.

And now at least this discussion thread is not completely useless :-)

Well if you're really interested in time travel fiction, nothing beats Doctor Who.

Specifically, 'Blink' is the best time-travel conceptual episode in recent memory.

True, very true. But my girlfriend has a negative interest in watching Doctor Who but loved About Time.

The only famous person that I can suspect of being a time traveler is Warren Buffet. It would make so much sense.

Perhaps Twitter is run by a cabal of evil time travellers who have created technology to check whether tweets reveal temporal anomalies and delete them automatically to cover their tracks and protect the status of an elite class in the distant future. What if all communications technology has been built around this capability; everything routed through a network of 'security agencies' that ostensibly protect the function of the current government but really work to design a future that benefits a rarified few.

That'd be cool.

I work for Twitter and can confirm that.

They were of course found the first time the study ran but the time travelers just kept going back in time and cleaning up traces of themselves until the tests stopped finding the evidence.

We could try to analyze the tremendous amount of visual data collected - photographs, video, CCTV footage. Discern abnormalities in appearance, clothes, possible gadgets used, movement, behavior. Given the abundance of recording devices today, chances are they got caught on tape or had their picture taken somewhere.

Of course there's always a possibility of false positives (e.g. Lady Gaga), but I think it may worth a shot :)

Well great. Now time travelers can't make prescient tweets because if they do it will reveal them.

I expect time travelers will agree on a responsible prescience disclosure system which uses something like http://www.proofofexistence.com/about.

I've never understood this logic. If say time travel is invented in year 3000. Then surely by 3050 it would be affordable for a certain segment of society. And be 3070 available for a mass market. And by 3100 available in watch form.

So shouldn't we expect there to be millions/billions of people interfering with the past. A significant percentage of which would be deliberately aiming to manipulate, destroy, communicate, affect and do all the things we expect people wouldn't.

Clearly it means either two things. 1: time travel is not possible. 2: going back in time forks the universe/space-time (About Time is a recent movie that proposes this).

It's been 60 years since nuclear power was invented, so in 10 years it'll be available for mass market? I'd also like my watch form plane.

What if it's so energy intensive that a future dyson sphere can only power it once a year. It doesn't matter how cheap the machine is, if the resources are expensive.

Indeed energy conservashion and entropy equalizashion was a large problem.

That poses the question whether a civilization that is advanced enough to build a dyson sphere would be able to build a second one somewhere else. The species would have enough time to collect energy and improve the machine until no reachable sun would be usable. And though we don't carry nuclear reactors in our watches (I guess smartphone would be more reasonable these days) we might carry fusion reactors in the year 38000.

Interventions in the past are possible as long as they don't change the future in significant ways. Think of it as Schrödinger's cat who is not dead as long as you don't look inside the box.

Almost, but I'd like to suggest an amendment to your first conclusion:

Time travel may well be possible, but unbounded backwards time travel is clearly not possible.

It may be the case that a machine will be invented that allows people to travel back only as far as when the machine was first switched on.

Similarly, a technique may be invented by which you may be able to temporarily travel infinitely into the future, and be snapped back to your present.

It may be the case that backwards time travel consumes so much of some finite resource that few or no future time travellers could possibly make it into our past.

Garry Kilworth's story "On the Watchtower at Plataea" involves a group of time travelers, from the story's "present", who push back earlier and earlier into the past... until they can't go any further because another group is coming the other way, from the past (due to the technology involved, each prevents the other from going further in their desired direction).

The "present" group then end up, essentially, in a standoff, watching the other group from a vantage point near an ancient Greek battlefield, and pointing out that they must eventually "lose" because both groups are now essentially in normal time. Which is moving from the past to the "present" from which they left.

Or we are the future as it's happening so its up to us to figure it out.

Wouldn't it be more useful to examine the stock and options markets for evidence of time travel? If I had a time machine, I would almost certainly try to use it for personal profit with maximum secrecy, rather than giving myself away by blathering about the future over Twitter.

Also, the study does not rule out Back to the Future style time travel, Terminator style travel, or Primer style traveler isolation protocols. Nor does it rule out multiple universe theories, such that future events become unpredictable to a past-traveler within a very short period of time due to the butterfly effect.

I think it's rather unlikely that we will find time travellers among us, for two reasons:

We don't seem to be anywhere close to inventing time travel. If time travel is invented, say, 10000 years from now, our moment in time might not be interesting enough to travel to.

All the funny paradoxes caused by time travel suggest that time travellers could fork a new branch in the multiverse, but that would not change the future they were coming from and they would never be able to return to that future. Hence, the interest in travelling back in time might not be that great, even if it were possible.

This only covers time travelers from the future. If one were to use similar methods to find time travelers from the past, we'd probably find millions of candidates :)

Billions, even. Since we're all time travelers from the past...

I believe finding time travellers from the past is trivial, especially those who travelled at a speed of 1s/s (or adimensional 1)

How does the measurement even work? 1s/s in what frame of reference?

It probably doesn't really work.

Here's a good way to spot them : http://www.smbc-comics.com/index.php?db=comics&id=3001#comic

Travel to the future is actually more probable(theoretically possible), I am basing this on a good explanation by Brian Cox(based on Einstein's theory of special relativity).

The basic premise is that to travel to the future an object would need to reach near the speed of light, the closer you get to the speed the further you can travel into the future, but travelling back would not be possible.

A direct quote from Brian Cox "If you go fast, your clock runs slow relative to people who are still. As you approach the speed of light, your clock runs so slow you could come back 10,000 years in the future".

I've always wondered about this. Now, what if, in "reality" after every unit planck-time the universe forks itself N times based on all the things that could have happened but didn't? And if you went back in time, you go back to that particular fork and so that there is no way to ever detect your time travel? I realize this a fairly naive idea..

Quite interesting with the methods used, alas the conclusion:

> Unfortunately, as of this writing, no prescient tweets or emails were received. Given the additional exposure that the public listing of this manuscript gains, we will continue to search, on occasion, for active tweets and emails involving potential time travel.

I thought this kind of stuff goes to http://vixra.org/

The core assumption here is that there is only one physical reality "spread" along the timeline.

Another representation of universe is that there are infinite number of parallel, simultaneous parallel realities all simultaneously existing in the present moment. There is no past and future.

Dodge that!

Of course the search didn't find anything. They already know what will be (was?) looked for...

The Doctor already made sure that efforts such as these would be doomed to failure: http://tardis.wikia.com/wiki/Bad_Wolf_virus

This paper was fascinating when I read it tomorrow. Unfortunately, I had to warn my former future self about their compelling results and prevent myself from posting all those really fun tweets.

The NSA probably has enough data at hand for answering this question.

This is actually something that's more reasonable. Presumably time travellers wouldn't advertise their presence heavily (can you say immediate and massive possible security hazard?) but one way to track them would be to look for net-traffic patterns which matched a person who was trying to localize the day and time, or who searched for things well in advance of them becoming known, general trends, or even being put up on the internet at all.

Like this: http://en.wikipedia.org/wiki/Chris_Benoit_double-murder_and_...

I'm sorry the Rothschild's have the monopoly on time travel for the next few millennium.

Citation bait == link bait

When I go back in time I'll be sure to setup a Myspace page.

Temporal Prime Directive

If we had time travelers, they would have been already comeback in the past and meet us from the future. It is useless to look for them. Wait for them and do something else.

What if there is no internet in the future?

Well, Guido van Rossum has a time machine.

this is HN not reddit/r/wtf !

Sorry, I use a VPN to the future ;-)

Satoshi is a time traveller...

ah this idea... Stein's gate anyone?

whats up with cornell's favicon?

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