Talk:Time travel

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Antiquity – Aug 2005 Aug 2005 – Feb 2006

Contents 1 I am a visitor from the country's past 2 Edits regarding Back to the Future example 3 Another scientific resource: Kip S. Thorne 4 Functional time machine? I doubt it! 5 Brian Peppers 6 Non-notability 7 The safety of Time Travel 8 Time Travel in popular culture 9 My question and a different proposal 10 Type 1.3 Fictional Time Travel 11 Presentism 12 Proposed section from Edward G. Nilges (Spinoza1111 06:41, 17 May 2006 (UTC)) 13 Techniques 14 Cleanup-verify 15 Anon edit 16 Ideas on time travel before physics 17 disputed 18 Rewrite in progress 19 User_talk:Dessydes/Interesting_Articles 20 Time travel concept's origin 21 Inappropriate link deletion 22 Time Dilation and Time Travel 23 Debating last edit 24 Is there any more information about that newspaper ad? 25 Worse case idea--nuclear explosion in a time travel device 26 Time Travel in fiction 27 A Few Things 28 YTMND disambiguation header (or: the vandals have won?) 29 Expert? 30 Is everyone here okay with we do like we did with Chuck Norris 31 Simple rule that proves that although time travel existed once, it doesn't any more. 32 What is this method called? 33 Simple English 34 Mental Time Travel 35 Time travel to the past 36 Duplicate matter in time?

[edit] I am a visitor from the country's past

What be this devilry--67.23.140.120 15:09, 16 September 2006 (UTC)

[edit] Edits regarding Back to the Future example

My edits about the time travel in back to the future 2 are about time travel. It raises the point about the possibilty or non possibility of time travel (how can one go back to a time, change it, then go back to their origanal time, with nothing changed, then have two people go back from that same point after and find all the changes - this raises a serious point about the possibilities of time travel). It is not Back to the Future "Trivia", it's not like I've added "The movie cost so many millions of dollars to make, and was a world wide hit" - that's "Trivia". What I added is relevant to the issue of time travel and is even more valid in this article than the one on the movie in question. 74.65.39.59 12:42, 27 July 2006 (UTC)

Using BTTF as an example would be justified if it clarified some point the article was making. In fact, the point being described in the section in question is remarkably simple: "any event that appears to have caused a paradox has instead created a new time line." Little further explanation, and no example, is required. The "example" from BTTF, in contrast, was tedious and silly and laughably convoluted: McFly & Doc go forward in time, McFly buys almanac, returns to present, present-day-Biff steals almanac, goes back in time, gives it to past-Biff, McFly & Doc also go back in time, but not as far, so it's the future of the time that Biff went to, find that it's a alternate time line... Augh; this is supposed to be a clarifying example? 74.65.39.59's addition was correct in pointing out that there's an apparent logical flaw in that mess of spaghetti, but much more to the point is the fact that it's a silly mess of spaghetti that doesn't clarify the thing it's supposed to clarify. KarlBunker 13:57, 27 July 2006 (UTC)

That's incorrect Karl. McfLy and Doc go back in time AFTER Biff so when Biff returned to the future he should have returned to the time HE changed, not the same one as Mcfly and Doc, this article makes no other mention of this and it is noteworthy! 74.65.39.59 15:45, 27 July 2006 (UTC)

I don't believe that you have addressed my objection. I said that the whole BTTF example was confusing and silly and didn't stand as an example or clarification of anything. If you disagree, please explain your disagreement. As it is, you just seem to be pointing out a logical flaw in a the movie, and that isn't relevant to this article. To clarify your point, try telling me what it is you're trying to say about this particular view of time travel, without referring to BTTF2 KarlBunker 16:40, 27 July 2006 (UTC)

Ok. I guess you don't get it, so i'll have to explain further. Here's another example. It's 2006, you travel back to 2045 with a friend. You leave him there, go back to 1980. Change something relevant to his life, go back to 2045 - the future. You wouldn't be able to go there as nothing had changed to collect your friend. Of course it wouldn't work like this. Once you changed what happend in 1980, 2045 would have had to change in the time line you are traveling in, as they would be a direct result of the new 1980 you created. If we are going to have the BTTF example in this article then it should be the full thing, the relevance of time travel, not just an half arsed little tid bit, because you think adding another two or three lines to it is "too much". Either have the full explantion of it, or delete the whole thing. 74.65.39.59 18:36, 27 July 2006 (UTC)

What you're describing is a logical flaw in the movie BTTF2; the movie doesn't correctly follow through on the implications of what the article calls "immutable timelines, 1.3" -- "any event that appears to have caused a paradox has instead created a new time line". Since I've removed the whole reference to BTTF2 from the article, and since you suggest "delete the whole thing" (I assume you mean the whole reference to BTTF2) it appears we're in agreement. KarlBunker 19:21, 27 July 2006 (UTC)

Yes we are! 74.65.39.59 23:58, 27 July 2006 (UTC)

I'm with Karl. It's the fault of bad writing, not bad theory. 129.237.90.24 04:27, 28 September 2006 (UTC)

Actually, the creators were aware that it could be seen as a flaw that old Biff returned to the same 2015 he left--see the BTTF Frequently Asked Questions which was actually written by BTTF creators Bob Gale and Robert Zemeckis. One of their answers deals with this question:

Q: When Doc and Marty are in 1955-A, Doc says they can't return to the future to stop Biff from stealing the DeLorean, because it would be the wrong future. But if that's true, how did Old Biff manage to get back to the same future that he left? Shouldn't he have come back to a different future?

A: As should be clear from the answer to the previous question, we believe Old Biff DID indeed return to a different future -- a "2015-A," which would have transformed around Marty, Doc, Jennifer and Einstein (just as Doc explains how 1985-A would change into 1985 and instantly transform around Jennifer and Einstein). This would happen AFTER Old Biff returned with the DeLorean. For this reason, we made sure that Doc had caught Jennifer and exited the McFly Townhouse before Old Biff returned. Thus, by the time Marty and Doc are carrying Jennifer back to the DeLorean, there COULD be other residents in that townhouse -- or perhaps the McFlys still live there. It is just as believable that the physicality of the neighborhood did NOT change as it is to believe that it did -- so we didn't change it. We decided not to make anything of this idea because this is one of those difficult time travel concepts that general audiences have a real hard time understanding. (Try explaining this stuff to your mother and you'll see what we mean.) A detailed explanation of it would have slowed down the story, and most of the audience doesn't ever think about it. That's why we made certain things ambiguous and left various things open for interpretation in hopes that the possibility of at least one or two explanations would be better than a "definitive" explanation that you could find holes in. Let's face it, time travel is fantasy, so there's no way to "prove" anything. As filmmakers, we try to create a set of rule for our stories and stick by them, and stay consistent within the little "universe" that we've created.

So, I think this suggests that BTTF II was never intended to involve parallel universes (Doc's blackboard diagram was just showing how the timeline had changed, not suggesting that the original 1985 still existed 'in parallel' with the new one), just some kind of "mutable timeline" which would actually transform around Marty and Doc and Jennifer in 2015 when Biff changed history in 1955. Hypnosifl 05:35, 28 October 2006 (UTC)

[edit] Another scientific resource: Kip S. Thorne

I ran across Kip Thorne's book Black Holes and Time Warps and gave it a read, and he has a pretty good section on the two-wormholes method of time travel and seems to have come up with it and wrestled with it prior to 1993, as well as provides an in depth analysis of the problems with his model time warp and concludes that we simply do not know currently whether the warp would break down or not. I feel this information is important to include, but I want a go-ahead before I add it in (and a series of limits, since I'm a bit new to Wikipedia editing).

69.118.138.25 11:35, 15 February 2006 (UTC)

This is already covered in the "using wormholes" section of the article. By all means add a citation to the book in the "scientific references" section, though. --Christopher Thomas 13:31, 15 February 2006 (UTC)

I think 69.118.138.25 needs some help in telling the difference between speculation (in Thorne's case, this speculation is apparently somewhat tongue-in-cheek) and established scientific fact. —The preceding unsigned comment was added by Hillman (talk • contribs) on 23:17, 16 February 2006.

There was a discussion of Kip Thorne’s time machine proposal on this talk page back in 2004, see the archive - in particular follow the link added on 2004-11-27.

RLS, 2006-04-22 —The preceding unsigned comment was added by 82.24.168.228 (talk • contribs) 09:44 22 April 2006 (UTC).

[edit] Functional time machine? I doubt it!

User:Benji64 added the following:

The basic rules of quantum mechanics and thermodynamics, as outlined above, only underline the need for, in any prototype or design of a time travel device, for a working flux capacitor. While there are many different designs of flux capacitor, the most commonly used one, designed by Albert R. Broccoli of the International Academy of Design and Technology, consists of a refined deuterium engine, with the D(subscript)2 fuel being ignited by a diluted red kryptonite (Ky) jelly. The apparatus housing this engine is traditionally constructed using light weight spun carbon fibre (as the mass of the apparatus which changes times is directly proportional to the amount of expensive deuterium fuel needed according to the functional principal E=1/2mv(squared)c) and a base such as Boron to counter the acidic exhaust released during combustion. The only completely functional time machine known to have been built was created by Martin MacFly of Philadelphia in the 1990's.

I am deleting this as nonverifiable. ---CH 23:17, 16 February 2006 (UTC)

And besides, he got it wrong - it wasn't Martin McFly, it was Dr Emmett Brown, in 1985, not the 1990s. --khaosworks (talk • contribs) 23:49, 16 February 2006 (UTC)

Flux capacitor? Is that some kind of joke? 216.195.147.234 (talk • contribs) (gwi.net anon; Great Works Internet of [[[BIDDEFORD, ME]]; geolocated near Wiscasset, ME)

What? Functional time machine? Could I get some verifiable evidince here? Mac Lover ^Talk_C 23:58, 26 August 2006 (UTC)

It also talks about red kryptonite, kids. It's vandalism. Delete that shite. 129.237.90.24 04:29, 28 September 2006 (UTC)

[edit] Brian Peppers

The link to a (now-deleted) article about a sex offender and internet meme Brian Peppers has been added and removed several times (most recently removed by me. I can not imagine how this is a relevant see also, but am open to further discussion here, if others can explain relevance. Thanks, --Hansnesse 06:41, 17 February 2006 (UTC)

Mike Church (talk • contribs) did provide an explanation here. My feeling, however, is that this is not a sufficiently well established link to warrent a see also. The link that the Peppers meme was associated with a time travel video game does not seem to me to be enough. I am not clear as to how the link would help someone researching time travel, for instance. --Hansnesse 07:00, 17 February 2006 (UTC)

It's too tenuous and indirect a link, and certainly not a useful reference. --khaosworks (talk • contribs) 07:24, 17 February 2006 (UTC)

Editors are advised that the Brian Peppers article has been deleted after legal review. I have removed the comments on this page because they contained derogatory information that may pose legal problems. Please see Talk:Brian Peppers and the related archive pages and history for the extensive discussion of this matter, and kindly refrain from re-adding the discussion that was here previously. If there are questions, please direct them to my talk page. The Uninvited Co., Inc. 20:50, 22 February 2006 (UTC)

Comments are restored, pending a specification of exactly what statements pose legal concerns. The only legal concerns voiced on the talk page you indicate were over use of a photograph in that article. Jimbo's comment specified that the article was being deleted due to being sick of the debate, and did not contain directives on removing comments only passingly related to that debate on talk pages. --Christopher Thomas 22:03, 22 February 2006 (UTC)

[edit] Non-notability

A Wikipedian claiming to be from the future is not notable [1]. Anyone can make any sort of outrageous claims (on the Internet, nobody knows you're a dog) and without proof, they're just that - outrageous claims - NOT notable. - nathanrdotcom ^{(T • C • W)} 21:59, 7 March 2006 (UTC)

I agree, and I think the "Alleged time travelers" section should be removed. I just checked, and the article on God doesn't have a section on "alleged gods, or offspring of god." KarlBunker 22:16, 7 March 2006 (UTC)

On the other hand, alleged time traverles are much rarer than alleged deities and offspring o f deities. JoshuaZ 22:20, 7 March 2006 (UTC)

I'll take care of removing it; if someone reverts it, oh well. - nathanrdotcom ^{(T • C • W)} 22:25, 7 March 2006 (UTC)

[edit] The safety of Time Travel

Perhaps there should be some mention of the possible safety concerns raised regarding time travel, in reality and in science fiction? NEMT 02:05, 12 March 2006 (UTC)

Time travel is incredabily un safe it would have to be tested several times with 100% results before any human could ever enter. User: VictorP

There should definetly be a warning label. We would not want to contibute to any children attempting time travel without proper supervision. BarkingDoc 03:46, 18 June 2006 (UTC)

Please keep your whole body within the time machine during travel. Time Machines Inc. are not responsible for the rapid aging or anti-aging caused to any arms, legs or other appendages separate from the rest of the body. If traveling to the past, please ensure that you do not kill your ancestors, or breach any part of the International Time Travel Act of 2135 - most notably, do not alter any major event in history, for any reason. Do not attempt to travel previous to the Big Bang, or after the Big Crunch, otherwise you may inadvertently implode the whole of spacetime. In case of emergency, panic. Have a nice day. Mike Peel 16:41, 24 June 2006 (UTC)

OK, before I was joking, but now I'm puzzled. I've reverted several different anon users who have been putting lines into the article saying that the safety of time-travel is not guarenteed. Why? Is there some reason behind this, or is it just some random person using different IPs to vandalize the page? Mike Peel 19:02, 5 August 2006 (UTC)

safety not guaranteed —ptk✰fgs 19:05, 5 August 2006 (UTC)

Ah, I guess that explains it. Thanks. Mike Peel 19:15, 5 August 2006 (UTC)

[edit] Time Travel in popular culture

Should there be a section for time in popular culture, and if there already is, where is it? 60.241.17.111 06:33, 20 March 2006 (UTC)

There's Time travel in fiction, which covers books, films, TV and games. KarlBunker 17:43, 20 March 2006 (UTC)

[edit] My question and a different proposal

My question is how can we reverse time since an event that we wish to observe or travel to has already been completed or passed, we cannot replace every molecule and particle in that exact same point since there are so many velocities and too many particles to account for. We can't recreate that event in the same manor, but what if we could traverse to a paralell universe that copies our every move, yet our universe began prior to the other(s) and according to calculus if one object has a head start then the other object must travel half the distance or change that the other has and then half of that, etc. etc. basically the other universe could be (trying to play catchup with us and its paralell universe trying to follow it).

Think of it like a aluminum pipe irragation system, you have a pipe and you turn the gates on one by one from the end of the pipe to the riser or beggining, the last gate has ahead start and most lilkely will remain ahead of the others, what if we could jump from the last row to the next and so on to traverse in what would appear to be time travel. Yet we cannot reverse the water and recreate a point that has already passed since the various water molecules have shifted along with the change of position of particles by the entire universe.

This is a basic summery of something I have thought about i'm not going into detail, but i know there are flaws and which ever ones you may find please inform me by replies, I would like to see the opinions of others and I will try to clarify my position better. It is best to keep an open mind since nothing can be proven wrong or write quite yet since technology does not permit it.

It is never wrongto learn, even if you must learn from an enemy. Senior '06

P.S. sry for my muck up earlier this is an odd forum.

--—The preceding unsigned comment was added by Altekameraden (talk • contribs) on 16:33, 13 April 2006.

The reason this is an odd forum is because it is not, in fact, a forum. It is for discussion about changes/problems in the article, not for discussion about Time travel itself.

Sorry, I forgot to sign my post, the above was me. 67.142.130.45 15:10, 2 June 2006 (UTC)

I think what the original poster is thinking about is called the Second law of thermodynamics which says entropy (i.e. disorder) always increases. It is one of the things known as an 'arrow of time' that sets a direction to time, that isn't inherent in the underlying fundamental laws of physics.Jameskeates 12:18, 18 August 2006 (UTC)

Thing is, the entire concept of time travel is not to recreate a point in time, but to move backwards (to use crude cartesian terms, to move down the "time axis") to when that time happened. You're not putting molecules back in place, they haven't moved yet. 129.237.90.24 04:36, 28 September 2006 (UTC)

[edit] Type 1.3 Fictional Time Travel

Some of the other time-travel types have some kind of scientific reference (like the Novikov self-consistency principle for 1.2), so does anyone know such information for the 1.3 type, particularly 1.3.2? Everett's many-worlds interpretation sounds relevant, but I'm not sure since it's not mentioned there. Cyllya 07:58, 19 April 2006 (UTC)

[edit] Presentism

Who actually advocates this position? Does it have serious advocates among physicists or philosophers, or is it just someone's pet theory? If the latter, it really doesn't belong on Wikipedia.

As given, the position doesn't make much sense -- if time is like a motion through space, then must there not be another time (time2) which that motion is with respect to? i.e. to say that now matter is in the present, and no longer in the past, but in the past matter was present in the past, and not in the (present) present, does that not only make sense if there is a time2 such that matter moves through x units of time1 for each unit of time2? Likewise, without a time2, how does one go back to the previous time to find no matter there? --SJK 04:14, 25 April 2006 (UTC)

dear sjk- presentism does have serious advocates- do a search on google if you are interested. The answer to your first two questions (as I understand them) is no. Time is a dimension- in many respects like the 3 dimensions of space. In other important respects it is not like them. For one thing, we can move more or less freely between positions in the spatial dimensions, whereas in the time dimension an observer always moves at the rate of one second per second (as measured in their own reference frame). I'm not sure that I understand your third question- it seems to presuppose the possibility of time travel, which is questionable at best- could you expand or re-phrase it?

Doctor Den 20.40 GMT 26 april 2006

Presentism shares some parallels with quantum theory. In quantum theory the past (and the present for that matter) is only ever that which becomes realised within the historical record (hidden or otherwise), be it a single photon detection, a photograph (interference pattern or family snapshot), an archeological artifact, a crime scene fingerprint, the stars in the sky, the universe. The "past" to which such records refer can be theorised. We can theorise ourselves occupying the past through films such as "Walking with Dinosaurs", or the family photo album, or any other historical artifact.

Classically theorised pasts, take place within the present, within experience. In quantum theory (as much as classical theory) the past is theorised as something prior to experience (prior to the present). But unlike classical theory there is a quantum theoretical "past" that can't be experienced. It can only be theorised - in terms of what might be realised in experience. A film such as "Walking with Dinosaurs", on the other hand, is both a theorised past and one that can be experienced. Before you see such a film, of course, you could describe it quantum theoretically - as something you might go and see, and might not.

Time travel, as classically understood, already exists - though films, museum artifacts, essays, and so on. Quantum theoretically this is the only kind of past we can experience. If we forgo the requirement that time travel into the past does not require experiencing the past we can travel into the other past - of quantum theory. One that is classically not there. The classical past remains back in the present, from which we departed.

--Carllooper 20:09, 14 May 2006 (UTC)

[edit] Proposed section from Edward G. Nilges (Spinoza1111 06:41, 17 May 2006 (UTC))

The following doesn't read with the NPOV and general equanimity of tone demanded by Wikipedia. I therefore ask the community whether any part of it has a place in discussion of modes of possible time travel.

"Virtual" Time Travel

One type of "time travel" that has been explored in science fiction and that presents no physical paradoxes or problems is "virtual" time travel.

Here, a sufficiently large computer or network assembles known facts about history, prehistory, geology and cosmology and gives the voyager a comfortable "virtual" voyage back to any date whatsoever. There's no problem that the voyager would be "in the wrong place at the right time" owing to the movement of planetary bodies, or eaten by savages, or anything else. Nor does the time traveler as a source of causality present any problems to the future.

Having a sufficiently large data base (that can be extrapolated) with complete sensory output completely solves time travel in the past. In the future, the designers would have to use extensive extrapolation, and they'd have to generate random scenarios. The experience would be more of a simulacrum of time travel than virtual time travel in the past, itself something of a simulacrum and both experiences would necessitate suspension of disbelief, rendering both at best educational tools (which could neither be used to change the past, nor make money in the stockmarket, unless, in the latter case, the designers are exceptionally good at making these sorts of extrapolations) and at worst carnival rides.

Interestingly, if Newtonian physics applied, time travel even in the future would be ultimately trivial because of determinism because of the in-principle determinism of position and momentum. However, a single paradox pair would remain. The time traveler would not be able to drop in on himself in the past or future for a chat because his existence in either would be virtual and read-only.

He could remain in the virtual environment, and create alternative futures for himself. We could even provide him with a switch to make an alternative future his actual future as long as we were prepared to support his physical existence in the real world. Phenomenologically this would for the single gazillionaire equate to time travel: but at this point we should probably leave him in his pod as C. S. Lewis left the masters of Belbury.

The experience of watching George Pal's The Time Machine was a primitive instance of this class as is the experience of reading history. As to travel in the future, we do so already, but at a constant rate, with moments of tedium. Spinoza1111 04:28, 16 May 2006 (UTC)

Whether or not the tone conforms to the Wikipedia style guide is open to debate of course, but the idea of virtual time travel is not just one person's POV. David Deutsch explores virtual time travel in his work 'The Fabric of the Universe' - a book that might otherwise be categorised as philosophy of science. With all due respect to the Wikipedia NPOV police - perhaps such policy appeasers could have a go at rewriting alleged POV pieces themselves ie. in what they consider the appropriate manner. --220.101.184.56 23:13, 17 May 2006 (UTC)

I don't think it is posable to have sufficient information to contruct an acurate model due to the uncertainty principal. However, perhaps an approximation could be made.

As for the problem of your interaction being read-only : if we assume a simulation could be produced, I'm sure it would be posable to modify it to ask "What If?".. including (but not limited to) "What If this used were to suddenly exist in this time and be able to interact?" and esily add/remove/modify people/NPCs/objects/particles by computer input. —The preceding unsigned comment was added by 84.92.62.165 (talk • contribs) on 00:00, 15 July 2006.

[edit] Techniques

The most familiar form of time travel is that depicted in literature, cinema, and television. The most common technique is to distract the reader/viewer by what is happening at any given moment ie. during the reading/viewing.

So long as any given moment (while we're reading/viewing) is sensible (sensory) there is a sense in which the time travel story, as a whole, makes sense. The parts add up to a whole.

Even if the relationship between parts remains intellectually inconsistent.

The dominant thread of the main article, is about the logic (or otherwise) of these relationships - how time travel might be intellectually (mathematically, philosophically) understood (if that were ever possible).

But the time travel (about which such intellectual effort is aimed) has it's origin in the very thing that excludes such explanation. The art of Time Travel.

Does the effort to understand this art by means of the very thing such art excludes, make sense?

--Carllooper 23:27, 18 May 2006 (UTC)

I'm sorry, but I can't answer that until this question makes sense. Are you merely saying that Time Travel as a plot device in fiction is different from Time Travel as a scientific theory? 129.237.90.24 04:39, 28 September 2006 (UTC)

[edit] Cleanup-verify

I added the flag. Quickly browsing I noticed several suspect, misleading, or absurd claims, including:

1. "A wormhole is created somehow. (one theory is from the time-space dilation of atomic particles under the heat and sub-pressure akin to that of an exploding sun)." Sub-pressure? Akin to? And you call this a "theory"?!
2. "One end of the wormhole is accelerated to nearly the speed of light, perhaps with an advanced spaceship, " How exactly do you propose to do that?
3. "Due to time dilation, the accelerated end of the wormhole has now experienced less subjective passage of time than the stationary end" This appears to involve a serious misunderstanding of the role of tangent spaces in Lorentzian manifolds.
4. "An object that goes into the stationary end would come out of the other end in the past relative to the time when it enters." This appears to involve a serious misunderstanding of local versus global distinction in Lorentzian manifolds.
5. "Another approach — attributed to Frank Tipler, but invented independently by Willem Jacob van Stockum [3] in 1936 and Kornel Lanczos [4] in 1924 — involves a spinning cylinder. If a cylinder is long, and dense, and spins fast enough about its long axis, then a spaceship flying around the cylinder on a spiral path could travel back in time (or forward, depending on the direction of its spiral)." I wrote the article on Van Stockum dust, which the author may have in mind here, but if so, his description of closed timelike curves in that spacetime is incorrect.
6. "A heavy atomic nucleus in a strong magnetic field would elongate into a cylinder, whose density and "spin" are enough to build a time machine." Are enough to? Come on now, have you built and tested this machine? Didn't think so.

I stopped reading at this point. ---CH 06:07, 19 May 2006 (UTC)

All of these do describe, in slightly mangled form, approaches to time travel that have been published about. The "time-hole" implementation of a wormhole saw light in Scientific American a while back, and I'd certainly hope that the authors of that article based it on more serious publications. The rotating, dense cylinder is called the Tipler device or Tipler cylinder, and was published about in serious literature. The rotating nucleus is "Forwardium", described by Robert Forward as a potential implementation of the Tipler device, though not one that's likely to occur anywhere (magnetic field strengths required were beyond those expected to be associated with any celestial phenomena). In short, while this article (and faster-than-light needs cleanup, I don't see anything fundamentally wrong with the parts you noted here. --Christopher Thomas 16:32, 19 May 2006 (UTC)

Slightly mangled? I think they are severely mangled and repeat that this article needs urgent cleanup. ---CH 02:31, 25 May 2006 (UTC)

I started to clean up the references/links, but more needs to be done. (E.g., reformat using the apppropriate citation templates). ---CH 02:52, 25 May 2006 (UTC)

I'm replacing it with an original research tag, which implies more of a problem (this is rife with original research right now.) Grandmasterka 01:57, 6 July 2006 (UTC)

[edit] Anon edit

An anon using IP address 65.185.104.28 (talk • contribs) (Roadrunner, geolocated near Findlay, OH) added this bizzare "threat". So, roadrunner anon, is this your idea of a joke, or what? Regardless, please don't do it again.---CH 02:22, 25 May 2006 (UTC)

Not a threat, a joke. The GPS is way off, and no, I won't do it again. Sorry. 65.185.104.28 (talk • contribs) (the woh.res.rr.com anon; RoadRunner; near Findlay, OH)

Watch out, everyone! I think we are being trolled. FWIW

1. "GPS" =/= "geolocation",
2. geolocation refers to the particular machine operated by Road Runner, not to the user

---CH 17:06, 4 June 2006 (UTC)

The article was routinely hit by a YTMND prank about an allegegd time traveler, which usually went by the name "Safety Not Guaranteed". A google search of "Safety Not Guaranteed" tells a bit more about it. Although the joke seems to have waned, this is a prime example. Just revert it and ignore... It is a couple of (probably) high-school aged lads with to much time on their hands and little creativity in their humor. --TeaDrinker 21:37, 4 June 2006 (UTC)

Yup, here he is again, it seems: 198.110.74.168 (talk • contribs) the grcc.edu anon ( Grand Rapids Community College in Grand Rapids, MI) ---CH 01:44, 17 June 2006 (UTC)

[edit] Ideas on time travel before physics

I've looked around and can't find information on this. What were cultural, literary, and people's info and stories on time travel before physics? The article is all about the relation between physics, Einstein, and such and time travel. Was time travel a concept that nobody thought of before physics and such? I searched the net but I can't find such info. DyslexicEditor 05:48, 29 May 2006 (UTC)

What do you mean by "before physics"? Before quantum physics, or Newtonian physics, or Archimedian physics? Before H.G. Wells? Before Charles Dickens? L.S. Mercier? Coyoty 14:30, 31 May 2006 (UTC)

Well, in the article time travel is all based on Einstein's faster than light theories and then the quantum probabilities. I'd probably say Newton's time and before would be before this stuff. I'd like to know if for instance in 1800 or before, time travel was an idea people had thought of. In relgious texts I've seen no cases of gods or anyone time travelling. DyslexicEditor 02:16, 2 June 2006 (UTC)

I think that in years like 1800 time travel would be more mystical then spirituial or scientific. It seems like the farter we go back (no pun intended) the less science we have. For example the Aztecs based almost all of the worlds happenings on gods and magic. (216.195.144.230 added this about 6/2/06 or so)

I think the faster than light = time travel thing is actually a misunderstanding of math and I'm looking for info on time travel not related to the quantum physics stuff. DyslexicEditor 11:55, 4 June 2006 (UTC)

Time travel is no misunderstanding of math! I don't see how you can have time travel without quantum physics. Do you mean like magic? User:VictorP

Magic or not, I'd just like to here of some idea of time travel before quantum physics came about. Anything in ancient myths or religion for instance? Maybe the idea never even occured to people? For instance, ebay sells magical time travel items, but I see no idea in magic of time travel before quantum physics. Rate of time though like things moving at different speeds (i.e. faeryland) is not actual time travel, though so that does not count. ... I hope to hear more ideas from people and maybe I may find out the info I'm looking for. DyslexicEditor 21:12, 8 June 2006 (UTC)

I think there are examples of time travel into the future but I can't think of any offhand into the past. - Tεxτurε 21:23, 8 June 2006 (UTC)

Quantum physics isn't required. Special relativity describes FTL and time travel as being equivalent, and it's considered classical mechanics. General relativity provides a more complete framework, and it too is a classical theory (non-quantized). For fiction, look at the usual suspects (H G Wells, and so forth). For myths, I seem to recall that one version of the King Arthur legends had Merlin experiencing time backwards. You also had various tales of the fae that had people who visited fae lands returning at some time arbitrarily far into the future. I'm sure you can find similar stories dating as far back as you want. --Christopher Thomas 21:29, 8 June 2006 (UTC)

I kind of groupped general relativity with quantum physics and basically anything from Einstein or after him. Hmm... just Merlin. Faerylands are what I mentioned where rate of time moves slower, but time is not actually travelled, like one hour in a place like that is one day on earth. But I looked at the Merlin_(wizard) and text search "time" and "back" and found it said, "T.H. White's Arthurian retelling, The Once and Future King, in which 'Merlyn', as White calls him, has the curious affliction of living backwards in time to everyone else." and says The Once and Future King was published in the 1950s. The article says that Merlin in the old stories basically just had prophetic knowledge of the future. DyslexicEditor 21:32, 9 June 2006 (UTC)

I'm planning on adding some information here into a section in the article of ideas of time travel before the 1800s (or lacktherof) as it'll likely get people adding to it. But I don't have time now. DyslexicEditor 01:54, 14 June 2006 (UTC)

Well, please check your facts. You referred above to "Einstein's faster than light theories", which is nonsense (you probably mean special relativity).---CH 01:46, 17 June 2006 (UTC)

I am not aware of any notion of time travel before popular ideas of science fiction. Magical writing did not include time travel. It definetly predates theories of relativity and quantum physics, but not by very much. I think this is largely because, as shallow as it may sound, the world didn't change very rapidly, so the notion of travelling in time wasn't especially romantic. Not until the industrial age, electricity, and the beginning of advanced technology did it occur to anyone that another time might even be interesting to travel to. BarkingDoc 03:43, 18 June 2006 (UTC)

There is a Japanese Myth about a man who enters an undersea kingdom and stays there for what seems like a week. When he exits, he finds out one hundred years have passed and he then shrivels into an old man. (somebody forgot to sign this)

Again, that is change in rate of time, not travel in time. DyslexicEditor 16:23, 7 July 2006 (UTC)

Okay well I meant to update it but I've not gotten around to it. Basically the things in this thread on the talk page are what I'd include, well Barkingdoc has the perfect quote, "I am not aware of any notion of time travel before popular ideas of science fiction. Magical writing did not include time travel. It definetly predates theories of relativity and quantum physics, but not by very much." That's pretty much good, just the first person pronoun needs to be redone. DyslexicEditor 16:23, 7 July 2006 (UTC)

Okay I wasn't going to but, I see time travel in fiction and it had what I needed. My sources are that, the Merlin wizard article, and some other wikipedia articles. DyslexicEditor 16:32, 7 July 2006 (UTC)

[edit] disputed

the stuff about real time travel isnt real --Turnip Wars 18:47, 21 June 2006 (UTC)

Wikipedia uses verifiability, not truth. DyslexicEditor 00:20, 25 June 2006 (UTC)

[edit] Rewrite in progress

I've taken a copy of this page to User:Mike Peel/Time travel, and am in the process of rewriting it. I would appreciate any suggestions on major (and minor) changes that anyone might have, and also comments on the changes that I make on the copy - please leave them here, or on the copy's talk page. I plan to merge any changes made on this page with the rewrite version, so no contribution between now and when I merge the page back to this one will be lost. Mike Peel 20:28, 24 June 2006 (UTC)

Please merge anything useful from temporal mechanics in as well. There isn't much (mostly it speculates about ways of resolving the problem of paradoxes). --Christopher Thomas 21:44, 24 June 2006 (UTC)

Whoops, I just turned Temporal mechanics into a redirect page to here. Of course, you can still retrieve the original (and paltry I might add) content of that article through its article history if needed. 24.19.184.243 04:49, 30 June 2006 (UTC)

I'm having a harder time than I expected getting my head around this article, hence the relative slowness of this rewrite. I'm currently thinking about splitting off the whole section of Time travel in fiction, leaving only a summary section near the bottom of the page, and combining any useful material from that section with Time travel in fiction. What do y'all think of this idea? Mike Peel 21:26, 30 June 2006 (UTC)

In principle this is a good idea, but in practice it seems like it'd be hard to avoid duplicating the discussion of speculative approaches to resolving paradoxes in both articles. If you can see a way to manage it, go for it, but there should be a Really Clear method of deciding what belongs in which article, so that material added in the future to either article can be moved to the correct location. --Christopher Thomas 05:32, 1 July 2006 (UTC)

I tentatively disagree. As the current content of this article shows, a lot interesting thought about time travel has been in the form of fiction. Also, there's not much connection between the current Time travel in fiction article and the "Time travel in fiction" section in this article. The former is pretty much a fanboy article that lists a lot of movies and TV shows that include time travel. The content in this article is analytical and makes actual points about time travel concepts. KarlBunker 12:04, 1 July 2006 (UTC)

I'm not making much progress with the copy of this article, so I've merged the changes I've made to the text back into this page. Although I think the structure of this article needs a heavy revision, I'll leave it as it is for now until the text is sorted out. I plan to make modifications directly to the page rather than a rewrite copy for the time being.

What I would like to see is an article that covers time travel in a scientific and philosophical sense only, rather than also discussing the use of time travel in fiction. That should only take place on Time travel in fiction. Note that this doesn't mean moving the whole 'Time travel in fiction' section as it is to that page - it means extracting the theories of time travel from that section first, and then removing what remains off this page. I want to get the first section sorted before moving onto the fiction section, though. Mike Peel 08:37, 6 July 2006 (UTC)

I can't back this up with references, but I'll bet that thorough research will show that many of the concepts that are necessary to a fairly complete discussion of time travel are concepts that were first introduced, and/or have been most thoroughly examined, in works of fiction. Another major use of fiction in this article is the use of well-known story lines (such as from the Back to the Future series) as examples. I wouldn't personally miss those pop-culture references, but it might be a chore to replace them with equally understandable examples written from scratch. "Discussing the use of time travel in fiction" is something I would be happy to see removed from the article. --KarlBunker 15:00, 7 July 2006 (UTC)

I would also suggest enriching the section on "Time Travel and Faster than Light" as it currently provides just a statement and it's probably one of the closest possibility to current level of physics in reality that we can understand. While the detail explaination on why faster than light tranmission of information is traveling into the past should probably be in the relativity page (strangely, I can't find it on either GTR or STR at the moment), it'll probably be better if there's also an explaination here in the section, including some reference links to GTR/STR. Allan Lee 15:58, 7 July 2006 (UTC)

The faster than light article also needs massive cleanup. It's been on my "to do eventually" list for quite a while (too big a task for me to start any time soon, though). --Christopher Thomas 16:11, 7 July 2006 (UTC)

[edit] User_talk:Dessydes/Interesting_Articles

May I suggest using this as a resource. I wanted to know if I could add it to the category. Haven't added much to it recently, save for the bibliography. Dessydes 18:56, 7 July 2006 (UTC)

[edit] Time travel concept's origin

User:DyslexicEditor added:

The idea of time travel did not exist before popular ideas of science fiction and the first widely-published story to feature time travel was in the late 1800s. Magical writing did not include time travel. Although there are stories of places where time moves faster or slower (such as being in a place where a week passed but on earth a hundred years pass), before the 1800s, no known story exists where time is actually travelled. The concept of Merlin living backwards in time, as well, was an adaptation of the classic story published in the 1950s.

I've moved this to the talk page, as I consider it unsuitable for several reasons:

• It uses DE's very narrow definition of time travel, specifically claiming that changes in the rate of time flow don't constitute time travel. I disagree, and apparently so did the anon who replied. There is no source for this definition, and it conflicts with at least one proposed mechanism for time travel.
• It doesn't provide a rigorous definition for what it considers to be time travel, or an authoritative source for such a definition.
• It doesn't provide a citation for "no known story exists". There's a big difference between none of the responding editors knowing of one offhand, and a demonstration that one isn't present.

Some additional objections by others are up at "ideas on time travel before physics", above.

I could see a statement along the lines of "perceptions of time travel changed dramatically with the introduction of time travel in science fiction" being valid, but that too would require citing someone who'd actually done a literature search and written about it. --Christopher Thomas 19:00, 7 July 2006 (UTC)

Some further comments (moved from "ideas" section above):

"popular ideas of science fiction" has no inherent meaning, and should be removed or defined.

"the first widely-published story to feature time travel" The story should be named. I assume you mean A Connecticut Yankee in King Arthur's Court? Defining "popular ideas of science fiction" to include this story would be a stretch.

"(such as being in a place where a week passed but on earth a hundred years pass)" This example isn't needed.

"The concept of Merlin living backwards in time..." You bring this up as if whatever it's referring to is common knowledge. --KarlBunker 19:13, 7 July 2006 (UTC)

Rate of time flow is not actual travel in time, it is just how fast time moves. If someone disagrees I'd like to hear a clear explanation. Also, my definition is the same as the first sentence or two of this article "Time travel is the concept of moving backward or forward to different points in time, in a manner analogous to moving through space."

Hi, I consider it very important to point out when exactly the idea of time travel came into public idea. I want a section on "Initial Ideas of Time Travel". Okay, actually I like "Time travel concept's origin" as a better section title.

For "rigorous definition for what it considers to be time travel", what I refer to is actual travel forward or backwards in time -- most specifically the ability to travel backwards (because forwards in time could be considered just being in stasis). Basically, like the article says, "Time travel is the concept of moving backward or forward to different points in time, in a manner analogous to moving through space." That's the definition I am using so I suppose I don't have to worry about sources if it's the article's. And time travel as a source is hard as it exists so far just in theory and fiction.

For, "It doesn't provide a citation for "no known story exists". There's a big difference between none of the responding editors knowing of one offhand, and a demonstration that one isn't present." well I don't quite know what to do to solve this one.

So, I have rewritten it almost completely:

The concept of moving backward or forward to different points in time, in a manner analogous to moving through space did not exist before the 1800s and the first widely-published story to feature time travel in fiction was in the late 1800s, A Connecticut Yankee in King Arthur's Court. There were various stories before the 1800s of places like faeryland that include people travelling to other worlds/planes where time moved at a faster or slower rate (such as being in a place where a week passed but on earth a hundred years pass), but it remained in synch with the time on earth, just moving at a different rate, and people could not travel to back and forth to different points in time. Magical writing and stories of dieties, even of omnipotent ones, before the 1800s did not include time travel. There also was an idea of Merlin living backwards in time, but this was an adaptation of the classic story published in the 1950s and not in the original story.

sources:

• this article
• time travel in fiction -- this is where I saw the earliest stories noted
• Merlin and some associate articles

Also for no known story exists and perceptions, basically I am referencing time travel in fiction.

I've kept "such as being in a place where a week passed but on earth a hundred years pass" because for now it helps clarify things--until some replacement wiki links can be made. Tir Na Noc (some spelling variation) was one place -- some Celtic faeryland.

So I'm hoping people can help rewrite. One important thing of this section is people will read it and improve it once it is up. DyslexicEditor 00:30, 8 July 2006 (UTC)

I think this is an interesting point, but it's already covered quite well in Time travel in fiction#Literature. The text in that article speaks in terms of what appeared in literature, and not in terms of "when the concept arose," but those two things are essentially the same. The text in that article also doesn't get into irrelevant diversions about things that aren't time travel, but are mentioned because they're a little bit like time travel. --KarlBunker 00:40, 8 July 2006 (UTC)

To respond to the easy points first - Wikipedia itself isn't considered a reliable source, if I understand correctly. Instead, cite the references that it cites, for appropriate points. I'd be very surprised if time travel in fiction contained a complete list, for instance.

Mostly, though, I take issue with the following statement:

Rate of time flow is not actual travel in time, it is just how fast time moves. If someone disagrees I'd like to hear a clear explanation.

Time travel is anything that takes me to a time that I wouldn't be able to reach by just sitting on my hands and waiting for my normal lifespan. Doing this in the _forwards_ direction doesn't break any known laws of physics - I can go arbitrarily far forwards in time just by camping out just above the event horizon of a black hole, waiting, and climbing back out to see how the galaxy's changed in the arbitrarily long time I've been away. There is no discontinuity that corresponds to me teleporting from the past to the future, which you seem to be assuming is required. Similarly, if I allow various speculative actions like travelling FTL or constructing closed timelike curves, I can construct situations where time appears to flow smoothly for me, and where my neighbours don't see me instantly blip out of reality, but where I can arrive at arbitrary points in the past or future. These violate your definition of time travel, but still accomplish exactly the same thing.

For a very simple case of time travel that violates your definition but moves you _backwards_, consider two nested spheres. Outside the outer one, time flows as normal. Inside the inner one, time flows in the reverse direction at the same speed, for lack of a less vague description. Between the two, time flows at a rate that's linearly interpolated between the two boundaries (a quarter of the way in, it's half-rate forward, half way in it's frozen, three quarters of the way in, it's half-rate backwards, etc). I could travel backwards in time without discontinuities by walking from outside to inside, reading a good book for a while, and walking out again. This is the same type of time-rate-warping effect that you dislike from stories of the fae, but constructed in such a way as to allow travel backwards, which seems to be one of the criteria you're using to judge validity of time travel mechanisms. This example is very obviously a contrived one (among other things, walking through the region of frozen time would present difficulties), but is sufficient to illustrate the point: teleportation is not required for time travel, and you seem to be assuming it is, as far as I can tell. --Christopher Thomas 02:58, 8 July 2006 (UTC)

Well I want something in this article about the origins of the time travel idea (not time travel in fiction, but how the idea came about) in the article so others will add more info to it. Can people who don't like it edit it into something they like? DyslexicEditor 15:00, 8 July 2006 (UTC)

I can't without more references. Literature is not my field, sorry. Perhaps one of the other editors following this discussion can. I'd certainly agree with statements saying that ideas of time travel were changed and greatly popularized with the introduction of science fiction as a genre. As for non-fiction, the best you're going to find in scientific literature is discussions based on implications of Special and General Relativity, but these will be talking about implementations, not origins, of the concept.--Christopher Thomas 15:38, 8 July 2006 (UTC)

My intention is so someone who does know can add information to it. I wonder what can we put up? Maybe we can just raise questions? DyslexicEditor 16:29, 8 July 2006 (UTC)

[edit] Inappropriate link deletion

"Another interesting concept for a human being is time traveling to HEAVEN Time Travel to Heaven Research Center"-I have deleted this as it just seems to have been put on this article so that this website can get hits. The name of the site, makemillions.bizland.com, also seems to entail that someone is trying to achieve some sort of financial gain from posting this link on a non-profit establishment-this shouldn't be tolerated. —The preceding unsigned comment was added by 172.142.214.60 (talk • contribs) 06:23, 21 July 2006 (UTC)

Web Portal Time Travel to Heaven Research Center is a honorable veteran of North American time travel movement. It describes a human fragment in this hyper physical concept. I think this is very important to have it in wiki. It plays a tiny accelerator for faster implementation of newest ideas and prophets. No, it does not have any monetary interest, although this is very scientific statement, if an internet site is done for profits or not. Plus it describes how our environment transforms in time. A big update is coming up once we discover additional resources. The name makemillions just shows that Big Guys on the market can benefit from it. Well, money still mean a lot for our economies. —The preceding unsigned comment was added by Eartheaven1 (talk • contribs) .

I deleted it because it seemed to link to unverified original research (see WP:EL#Links_normally_to_be_avoided number 2). In general, propritors of a website (or people with affiliation to a website) should not insert links to their own site. This is primarily geared at limiting conflicts of interest. --TeaDrinker 23:54, 21 July 2006 (UTC)

[edit] Time Dilation and Time Travel

There is at least one section in this article referring to Time Dilation as Time Travel. I don't think this is correct. They are not the same thing. Or, at least there needs to be more elaboration on the subject.Gagueci 18:10, 25 July 2006 (UTC)

I think the point is that time dilation allows you to 'travel' into the far future by travelling fast through space. It's not true time travel, but you can potentially live to see things that would otherwise have occurred well after your death. Mark Grant 01:18, 26 July 2006 (UTC)

Maybe so, but it doesn't help by telling me that on the talk page. Gagueci 22:58, 26 July 2006 (UTC)

I have to agree with you 100 %. Unless someone proves otherwise, nowhere in the theory of time dilation or any of the space-time relativity theories does it show that mass or energy enter into a future or past event and become a part of it. Time dilation shows the different rates of time passage, but to each observer observing him/herself the passage of time is always normal. As far as two (or more) observers observing each other, neither will see the other(s) entering a past time and becoming part of a past event, nor observe the other(s) entering a future time and becoming part of those events. What they will observe is the different effects of aging on each other (different rates of time change). Different rates of time change are not the same thing as going back into a past event or moving forward into a future event. The direction of "movement" is always from the past to the future through the present. Both observers are always in present time, even relative to each other.

Thus I don't feel the discussion of time dilation, other then to point out it isn't the same thing, belongs in an article on time travel.

The concept of Presentism, whether it is a real or imaginary philosophy, is an important part of an article on time travel. It can be used to argue that since past time no longer exists and future time has yet to exist, that true time travel is not possible. Even if someone were to miraculously design a working machine to actually travel through time, can one really become a part of that which no longer exists or is yet to exist (maybe)?

[edit] Debating last edit

It was reverted, but I still want to debate it. It is this [2]. Basically, I disagree with that. What we are seeing are shadows of the past and not the past. Anomo 08:38, 18 August 2006 (UTC)

[edit] Is there any more information about that newspaper ad?

I searched and the most I could find was supposedly it was in The Coppenhagen Post. wiki.ytmnd.com/Image:Timetraveler.jpg is a picture of it. I can't find what year it was. I also am doubtful that the mullet man next to it came with the ad and was added later to make the thing into a joke. Snopes.com has nothing on it. I know someone on YTMND tracked down the current owner of that PO Box, but I think the ad was run in the 1990s and so whoever rented it during the ad was several owners ago. I am not asking about wiki.ytmnd.com/Safety_Not_Guaranteed the fad that started after the ad, but the ad itself and I remember seeing a picture of the ad before YTMND's website even started. Anomo 17:10, 23 August 2006 (UTC)

[edit] Worse case idea--nuclear explosion in a time travel device

Keeping Murphy's Law in mind, "whatever can go wrong, will go wrong"; what would be the effect of a nuclear explosion in a time travel device while in the transition phase, between the destination of the past, present, or future? It could be a nuclear explosion by a weapon, or the power source of the machine. Wouldn't that really mess things up in a very bad way, sending radioactive material across time, and possibly destroying the universe as we know it? I think it is great that we can not travel faster than light, or backwards in time, because so much could go wrong. After all, look at all the Nazis were able to accomplish, such as the Me 262. A time travel device with a swastika on it, is only one of the many problems a real time travel device would present.204.80.61.10 18:59, 23 August 2006 (UTC)Bennett Turk

[edit] Time Travel in fiction

Time Travel is fiction. Sure, we may want to have information about the "scientific and philosophical basis for time travel, but face it, Time Travel Is Fiction. I'm reverting the change on BTTF, because it is a valid reference for the item specified. Mike Peel has made reference to the fact that he wants a physics basis here, and he wants all fiction in Time travel in fiction, but I could say the same thing about this article that it should be a time travle in fiction article (because time travel is fiction), and that the scientific basis should be in an article titled Time travel in science. I think mixing the two is really the only way to go. If someone wanted a reference as to why people think there could be "skewed timelines" BTTF2 is the canonical (yes, canonicial [[3]]) reference for that theory. McKay 13:39, 29 August 2006 (UTC)

I would argue that time travel is a philosophical and scientific possibility, which is very commonly discussed in fiction. It is not purely contained in the fiction written about it, though - and although ideas about time travel commonly appear in fiction, I'm not sure that that is always where they were first described (but I could be wrong about that - I don't have any references for that, just a gut feeling).

I have changed my mind about what I said above - it seems that discussion of time travel occurs much more in fiction than most philosophies that I've encountered. I would still like to see the removal of the 'time travel in fiction' section, such that we have an article that discusses the overall philosophies, with references to their original development, and the most prominant uses of them in fiction (although that could be the same thing in many cases). I don't have enough time at the moment to undertake such an extensive rewrite of the article, though. Mike Peel 15:52, 29 August 2006 (UTC)

I concur, I like that layout. I don't have time to do the rewrite either :( McKay 18:04, 29 August 2006 (UTC)

[edit] A Few Things

The article states, "Indeed, Stephen Hawking once suggested that the absence of tourists from the future constitutes a strong argument against the existence of time travel...". The absence of tourists from the future is not a strong argument against the existence of time travel. It is simply a strong argument that there is only one timeline or one universe. String theory and more specifically M-theory indicates a mathemetical possibility of multiple or parallel universes, though it is as of yet unable to be tested experimentally. If there were an infinate number of parallel universes then the chance that a tourist from the future would end up in our universe is 1/infinity which is next to 0%.

Concerning whether or not to add information about potential time travelers, I think that you could add a small section about it so long as there is some evidence to back it up. For instance there was a man named John Titor who claimed to be from the future. While normally people such as this would be ignored as liars, John made predictions which later came true. He Said in November of 2000 "The basics for time travel start at CERN in about a year and end in 2034 with the first "time machine" built by GE."

From the CERN website: http://public.web.cern.ch/Public/Content/Chapters/AskAnExpert/LHC-en.html#qb4 "Black holes?

According to some theoretical models, tiny black holes could be produced in collisions at the LHC. They would then very quickly decay into what is known as Hawking radiation (the tinier the black hole, the faster it evaporates) which would be detected by experiments. Cosmic rays with very much more energy than that available at the LHC, could also in principle produce black holes. However no evidence for such phenomena has so far been found."

He also stated that Cesium clocks would be used as part of the time machine design because they are the most accurate keeper of time and as such allow a time traveler to lower the divergence between their universe and the one in which they end up. http://tf.nist.gov/cesium/fountain.htm

He also predicted civil unrest in the US as a result of the 2004 election, which turned out to have massive voting fraud carried out by the republicans.

I'm not saying that he was indeed a time traveler but he does give semi-detailed explanations for how things work and minor predictions about future events. As a result it might be worth it to include a small section concerning him or other supposed time travelers.

http://www.johntitor.com/ http://www.anomalies.net/time_travel/john.html http://www.anomalies.net/time_travel/Iamfrom2036.html TheAnimus 01:15, 1 September 2006 (UTC)

Puh-lease. Being able to spout technobabble does not constitute "some evidence," and John Titor's long list of laughably incorrect predictions would seem to constitute evidence that he wasn't a time traveler, or at least that he must have been a really bad "history" student back when he was a kid in the 2020s. KarlBunker 14:45, 1 September 2006 (UTC)

I didn't say he was actually a time traveler I said that he has semi-detailed explanations, which he does, and they make sense and eliminate paradox's with time travel. I simply think that it's related to the topic. Also his technobabble actually makes sense and he references real companies and research. How does it show he was a bad history student? And even if he is a bad history student what does that have to do with anything? If someone is bad at spelling does that make them a bad person or less credible? Einstein wasn't good at a lot of things in school but no one cares because he was still good at math. And finally he blatantly stated that there are an infinite number of parallel universes. For every possible action that could have happened there exists a universe in which it did happen. He also stated that when going back in time the farther you go back the more divergence there is between your universe and the one you end up in. If you go back only 5 years there is only a small divergence of say 1%. This means that only 1% of the events in the universe you end up in are different from the events of your universe. So when he goes back 40 years or 70 years the divergence increases and as a result he cannot 100% accurately predict the future because in our universe some of the events might be different. This is why if you wanted to go back in time and meet Jesus you probably would not be able to because the divergence is so high that he may not even exist in the universe that you end up in. If nothing else you can say that he has a unique theory on how time travel works and it makes as much sense if not more than most of the theories already on this page. So even if he isn't relevant enough to include in this topic then at least his theory and explanation of time travel could be added as one of the possibilities listed. TheAnimus 21:29, 1 September 2006 (UTC)

[edit] YTMND disambiguation header (or: the vandals have won?)

No one is visiting Time travel to learn about "safety not guaranteed". An example of a proper dab header would be pointing to something else also called "time travel". See also WP:DENY. —ptk✰fgs 19:31, 6 September 2006 (UTC)

Agreed. We can simply keep reverting the vandals. This is an encyclopedia and putting this barely notable junk is unencyclopedia and unacceptable. We can simply keep reverting the vandalism. This is a wiki after all. JoshuaZ 19:34, 6 September 2006 (UTC)

[edit] Expert?

Hmm, an expert on time travel... Well, since no one has ever time travelled (Aside from the YTMND guy [and we don't know if he survived his second mission]), we are stuck to theoretical exports. I'm not Kip Thorne or Steven Hawking, but I've read much of their work. I have extensive experience in the physics and math pertaining to time travel (I did a Junior research paper on Time Travel in school). So while I don't know if I'd consider myself an "expert", I think I'm pretty close. It said that information was requested on the talk page, so here I am. McKay 03:10, 10 September 2006 (UTC)

[edit] Is everyone here okay with we do like we did with Chuck Norris

I don't want to go doing this after nobody answers this question on the talk page after a week and get reverted minutes after doing this so please answer:

Chuck Norris has:

<!--
Welcome to Wikipedia! Please remember that this is an encyclopedia 
and that we cannot accept non-factual or unverifiable information, 
speculation, and opinion. While they may be funny, posting "facts" 
from the "Chuck Norris Fact Generator" to this article is getting 
really old and will be reverted immediately.

Please refer to

http://en.wikipedia.org/wiki/WP:V

If you wish to test out the page editing process, you may do so in 
our Sandbox located at http://en.wikipedia.org/wiki/Wikipedia:Sandbox

If you're interested in becoming an editor, check out
http://en.wikipedia.org/wiki/WP:TUTORIAL

Thank you for your interest!

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We should do the same thing here. Who agrees or disagrees? Anomo 04:08, 20 September 2006 (UTC)

Do we need to? Even if it's the same stupid joke getting added every time, the level of vandalism here is pretty low. —ptk✰fgs 04:17, 20 September 2006 (UTC)

So the Norris stuff was a lot worse? Anomo 04:44, 20 September 2006 (UTC)

I don't know. Whenever I smell a vandal, I do a quadruple roundhouse kick. —ptk✰fgs 04:57, 20 September 2006 (UTC)

There aren't any unblocked vandals. Only ones Chuck Norris hasn't gotten around to roundhouse kicking yet. Ok, joking aside the vandalism level here seems low enough not to need it. JoshuaZ 05:00, 20 September 2006 (UTC)

[edit] Simple rule that proves that although time travel existed once, it doesn't any more.

First, we need to agree there are FOUR means of invention.

First = Error : An existing machine through fault (mechanical or programming) forms another function it was not originally intended for

Second = Independant Thought : An idea or concept forming into a workable object or machine through usual design means

Third = Amalgamation : Two or more existing designs or machines converted into one, making a completely new machine for a completely different purpose.

Fourth = Experiment : A series of tests or experiements with unknown outcomes creating a working concept for something new.

Now IF time travel is possibile, then it is only logical to assume it has to be created out of at least ONE of these means. So for example Mr TM (time machine) invents a device or concept into a useable means of going back in time. From that point on and way into the future, due to the laws of causality, NO-ONE is allowed to interfer with Mr TM, any of his ancestors, any of the people that affected his ancesters (for example a person introducing Mr TM's grandparents together)and so on, in effect, in a country like the UK with approx 72million people in it, just one person's existence is goverened by approx 10,000 in just 4 generations so go back longer and you're talking millions of people, all needing to be where they are, when they got there originally. Stopping one to ask the time could change everything. And with human nature, we'd cock it all up!!!

So the outcome = Mr TM doesn't invent time travel as he was never born. (paradox created with existing time traveller)

Ok, we dont give up so natural progression means Mr STM (second time machine) invents it instead of Mr TM and we're back to stopping anyone in the complete future (before we're all dead through world end or other means). Now, this is where it gets difficult. Ignoring the fact it will happen again and stop Mr STM for being born, we have a second person in the loop. That being the original time traveller that ended up killing off Mr TM. If he is killed by the second significant time traveller then he was never around to kill the original Mr TM out of exsistence.

This can go on and on and on until finally...... we live in a time line where time travel never gets invented because all of the causality loops have been played out to the point they cant be changed anymore (the absence of a time travel machine being invented).

Conclusion: Time travel has already been invented, it will also be invented in the furure, but the fact we're still here without it means it will never be invented again.

Catflap31 07:30, 5 October 2006 (UTC)

Fallacies

• Some kinds of time travel don't allow the time traveler to go back in time to a location where paradoxes are possible, thus eliminating the possibility of the specified paradox.
• This also assumes a many-worlds interpretation, which says a paradox spawns a new timeline. Some interpretations don't allow paradoxes, and some make the universe cease to exist (which, for the record, hasn't happpened if you're reading this)
• The nature of invention is slightly mistaken. Let's look at some of the big inventions of the past few hundred years, that might be on-par with the time machine, The Automobile, the airplane, the computer, and the telephone.
  • Automobile -- The WP article on the automobile mentions that Benz is credited with invention, but admits that other inventors were working on it at the same time.
  • Airplane -- The wright brothers are commonly credited with inventing flight, but others actually flew first, some 50 years prior.
  • Computer -- This is much more recent than the others, so the history is better recorded, but similarly, it was being developed by different people at different times.
  • Telephone -- Same as Airplane. In fact, WP has an article about the controversy at Invention of the telephone.
  • so, killing the inventor doesn't mean that something will be not be invented. Usually an invention is a race. McKay 14:18, 5 October 2006 (UTC)

[edit] What is this method called?

I can't seem to find this "method" of time-travel that I have read somewhere (it came from a reliable source and is considered to be scientific). What do they call it when they place someone on a spinning land mass that rotates at incredible speeds? Basically, the land the person stands on spins so fast, s/he sees the outside being a lot faster, while s/he ages slower and seems to be moving slowly, if you were watching from the outside. THis allows for time travel into the future. 24.23.51.27 06:36, 9 October 2006 (UTC)

Sounds like the person is slowed down because they move so fast that their subatomic particles can't keep up, but no time is actually travelled. Or do you mean when Superman spun the earth to travel in time? Anomo 07:32, 9 October 2006 (UTC)

I think what you're referring to is "Time dilation", it is indeed a form of travelling into the future, but you would have to be travelling at close to the speed of light for anything effective. see also Lorentz factor. McKay 14:06, 10 October 2006 (UTC)

No, it's not because time dilation is just slowing you down, but you are not jumping anywhere. People can still see and interact with someone in time dilation. Putting food in the freezer is not time travel! Anomo 14:20, 10 October 2006 (UTC)

Let me talk wahhh- Yeah sure you can do that but what I think Anomo guy or w/e wants to know is what is this theory/meathod or whatever it is called. I also wana say maybe if you go faster than the speed of light then maybe you could go back in time if you cna slow it down at near c speeds —The preceding unsigned comment was added by 70.120.224.24 (talk • contribs) .

It is time dilation, and we are all traveling through time. And just because you can "interact" with someone doesn't mean taht they aren't time travelling. If someone was traveling through time twice as fast as you were (using a "time machine", maybe like the one used in The Time Machine), you could probably still interact with them, Their voice might be changed, but it would probably be understandable (like hobbits talking to ents). If I'm experiencing time dialation, that is considered time travel, as it is altering the speed at which I travel through time. Travel to the past is usually just considered traveling through time at negative speeds (unless one considers using wormholes, like bill and ted's presumably uses). McKay 17:36, 11 October 2006 (UTC)

[edit] Simple English

May it be possible for someone in the near future to please write this article in simple english? --Steven91 22:36, 10 October 2006 (UTC)

Define "simple english." The article is in simple english. I have no problem comprehending it. If you don't understand an aspect of something, research it further yourself. This article can't cover every single word and theory that ever existed. It's only relative to Time Travel. What parts of the article don't you comprehend? IceSage 22:26, 16 October 2006 (UTC)

see Simple English Wikipedia. This isn't to say that there's anything wrong with the content on this page, but someone with a more remedial level of English might have some difficulty with some of the concepts contained herein. McKay 14:29, 17 October 2006 (UTC)

[edit] Mental Time Travel

I'm shocked to see that the whole wiki doesn't have anything on mental time travel. Mental time travel is the theory of that in which your mind can actually recall memories via travelling through time... That these memories are not actually stored in our brain, but are recalled and searched for via mental time travel. Simply facts like names, places, etc are physically stored in the brain. But memories of these events are recalled via this "mental time travel" which works in both the way we anticipate things will happen (even if we can't actually "see" what's going to happen) and remembering past experiences. IceSage 22:26, 16 October 2006 (UTC)

Soo, Erm, verify that somehow? 68.239.4.75 16:44, 20 October 2006 (UTC)

[edit] Time travel to the past

The section with this title says that three methods of time travel are "theoretically possible". First of all the third item should not list "Warp drive" as this is pure fiction. 172.143.157.207 16:20, 25 October 2006 (UTC)

I changed this to reflect that it was supposed to refer to the "Alcubierre drive" (which is an allowable solution in general relativity, although it is not entirely clear that the 'warp bubble' would actually move faster than light as seen by external observers) rather than the Star Trek concept of "warp drive". Hypnosifl 21:10, 27 October 2006 (UTC)

Secondly, I think "theoretically possible" is an overstatement for the first method since (as noted at the close of the detailed description) as it's not possible to cross the light barrier (in either direction) in relativity, and this is neccesary for the time travel "solution". If the wording has come directly from reference four, and we keep it, I think it should at least be quoted as it is rather far from a neutral view. 172.143.157.207 16:20, 25 October 2006 (UTC)

Although crossing the light barrier is not theoretically possible, tachyons which always move at FTL speeds are at least not forbidden by relativity, although perhaps it should be noted that when physicists try to model tachyons in quantum field theory, they conclude that it would not actually be possible to use them to transmit information faster than light (see the last part of the discussion on this page), which means you couldn't send a signal into the past with them even if they existed. Hypnosifl 21:16, 27 October 2006 (UTC)

[edit] Duplicate matter in time?

I haven't been able to find a discussion or theory regarding the fact that if someone or something goes back or forth in time, its matter would be duplicated. In fact, the "start" universe would lack the subject's matter (or more specifically, its particles) and the "ending" universe would have them duplicated. How would matter be balanced once the past (Universe+1 matter) catches up with the moment after the subject is transported (Universe -1 matter)?
I think this issue/paradox is worth including in the article, but haven't found any good sources. --okriM 22:03, 16 November 2006 (UTC)