Talk:Time travel/Archive 6

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Safety

Are there any theories on the safety of time travel? --NEMT (talk) 20:30, 20 November 2007 (UTC)

Yes, its well known that when time travelling your safety is not guaranteed, especially when you push it to the limit. —Preceding unsigned comment added by 88.106.16.89 (talk) 01:21, 27 February 2008 (UTC)

Common wisdom suggests that one ought to bring one's own weapons when time traveling, especially if one has only time traveled once before. 76.192.168.161 (talk) 15:47, 16 August 2008 (UTC)

You could get lost in a completely different parrallel universe and never be able to return to your own. —Preceding unsigned comment added by 222.153.21.181 (talk) 10:34, 3 July 2008 (UTC)

If it's 40 years ago and she looks like your Mother, chances are that she is. 89.242.29.125 (talk) 17:24, 17 October 2008 (UTC)

make money on time travel

immagine this, you find a wormhole connecting a point in the past with the future. near the worm hole is a dollar. you pick up the dollar and throw it into the future end. now when you find the worm hole it has two dollars in front of it. you pick both up and repeat the process.soon you'll be very rich.what concerns me is that this can be done with anything. by this means you can in a sense create mass or produce exponentional amounts of energy. if this is done with energy would there eventually be a really big explosion from the infinite loop? —Preceding unsigned comment added by 70.111.221.127 (talk) 03:03, 14 February 2008 (UTC)

If you through one dollar into a wormhole and waited X amount of years, the dollar would re-appear (one dollar, not two)

You would still only have one dollar. --RLent (talk) 20:24, 17 April 2008 (UTC)

That is probably impossible, given that wormholes are designed to travel space-time, not copy items. —Preceding unsigned comment added by 68.48.94.53 (talk) 11:45, 23 May 2008 (UTC)

Designed? BreathingMeat (talk) 01:07, 27 May 2008 (UTC)

Anything that can be used for time travel should also be usable for having at least the appearance of multiple "copies" of the same item--think of how if you went back in time and met with your younger self, it would appear as if there were two "copies" of you in the same place. But if something like the Novikov self-consistency principle is true, you could only actually spend the dollar that had been through the time machine the most times and was thus the "oldest"--if you tried to spend any of the "younger" versions of the dollar, you wouldn't be able to send it through the time machine again and this would be inconsistent with the fact that you can see "older" versions lying around. Hypnosifl (talk) 19:39, 27 May 2008 (UTC)

You will have zero dollar because the dollar that you just threw into the wormhole would appear in the past but would end up going into a completely different parallel universe. The guy who threw it into the wormhole is not the same guy receiving the dollar. —Preceding unsigned comment added by 222.153.11.81 (talk) 06:14, 4 July 2008 (UTC)

Time travel is not only possible; it is actionable.

Time travel will certainly become a reality; all things the human mind can comprehend can be accomplished. The claim that only photons can travel at the speed of light will be ridiculous to a first year student in the year 3008. Ask almost anyone on the planet 108 years about travelling from New York to San Francisco in 8 hours and they would have said its impossible. Ask someone 508 years ago about travelling 70 miles in one hour and they would have said thats impossible. Any problem is solvable given enough time and resources. The atom did not even exist in the year 1744, at least not to scientists of the day, yet in 1945 we smashed a few together over Japan with spectacular results. One new discovery leads to discovering something else which will lead to travel faster than the speed of light. If the human brain can think it, then it can be done. —Preceding unsigned comment added by 131.44.1.69 (talk) 11:03, 27 February 2008 (UTC)

You might want to consider the difference between science and wishful thinking

I can think of jumping to the moon, but I can't do it. There is a difference between that which is difficult and that which is impossible. Just because difficult things have been done does not mean that there are no impossible tasks.--RLent (talk) 20:27, 17 April 2008 (UTC)

I think that jumping to the moon is much more likely then travelling in time, but i believe both scenarios are accomplishable. - Thymo —Preceding unsigned comment added by 62.63.25.18 (talk) 12:11, 19 May 2008 (UTC)

Just because you can imagine something does not make it possible. Time travel to the past is only possible if the past exists in such a state that it can be travelled to. If the past only exists in memory and physical evidence, then no amount of technology will make time travel possible. Personally, I think the idea of time travel to the past is ludicrous, not from a technological stantpoint, but merely the idea that history is stored somewhere such that you can revisit it if only you can find the universe's rewind switch. 91.109.175.252 (talk) 17:59, 6 October 2008 (UTC)

But have you studied relativity at all? Are you familiar with the relativity of simultaneity, which says that different inertial reference frames can disagree about whether two events at different locations happened at the "same time" or not, and do you understand that in relativity there can be no physical reason to prefer one inertial reference frame over any other? This is the main reason that most physicists take the view that time is just a dimension in 4D spacetime, rather than the view that "only the present exists" (known as presentism). Hypnosifl (talk) 00:30, 8 October 2008 (UTC)

We could evolve into creatures that can convert mass into energy somehow and jump to moon. —Preceding unsigned comment added by 222.153.21.181 (talk) 10:38, 3 July 2008 (UTC)

Once, mankind thought the Earth was plain.

Technology is not bound to discover time travel. If mankind survives (which curiously always find its way out), technology will evolve into new dimensions. When that happens, I'm so sorry, but imagination will make everything possible.

One thing is sure: time travel is something mankind is not yet prepared for. Too much skeptics. Someone out there is laughing out loud watching us keeping our feet on the ground. Dream, little guy.--Fluence (talk) 04:33, 1 November 2008 (UTC)

This "time travel" is deemed probable rubbish with some experts, so, I think that you are wrong. Thanks! HMAS The Rory (talk) 07:01, 1 November 2008 (UTC)

Who cares? This is a talk page to discuss the article, not the feasability of time travel. Unless someone has reliable secondary sources that they're here from the future, it's a moot point. Dayewalker (talk) 07:07, 1 November 2008 (UTC)

Right. Seeing I lack the ability to "be happy" during these, I should probably go, because then that would hapen, and we don't want that... Bye - I'm going back to the Slitheen Block. Rory the Slitheen (talk) 07:19, 1 November 2008 (UTC)

Not Possible

There are some physicists that think (sorry, no citations) time travel is not possible because time has no dimension. Since there is no there to go back to, or to go forward to, any talk of time travel is silly.

To be complete, this article should add a contravening section with this point of view. Shawncorey (talk) 00:17, 31 March 2008 (UTC)

You really need citations for a claim like this; it sounds more like the philosophical notion of "presentism" discussed in the article, I've never seen any physicist use this argument, and it doesn't sound like a genuinely physical argument either, so I would suspect you're just misremembering. Hypnosifl (talk) 03:41, 1 April 2008 (UTC)

what you ARE is a collection of energies that is no longer where you WERE, but has migrated to a new location, there is no travelling back to where they WERE and expecting to find them there. For some reason this absurdly simple thought has escaped some modern science due to a mis-reading of a space-time charting of changes as a map of some real places that still exist. The past is chartable but not there any more, and the future only exists as thoughts in the imagination of men, it has no REAL location and it should be absurdly obvious why no one has yet travelled back from there, because there is no one there yet.

Consider, if all moments in existance are said to be like a strip of 4-D film, then pray tell me who made the film strip and WHEN? secondly tell me how any of those moments can be considered by anyone as THE present moment? thirdly tell me what is moving? all those moments would appear static to a godlike being, yet we are fully aware of motion and that would not happen unless we were somehow more than 4 dimensional and moving through all these moments... and if that were so, it would mean that we were not human, but some sort of omni-dimensional soul moving through all those souless bodies statically awaiting our presence. And while that may be possible, it does not seem very likely!Jiohdi (talk) 21:49, 8 April 2008 (UTC)

Time travel is possible. And I have already proved myself right because we are travelling forward through time right now. If we can go forward, why not backwards? We just need to find out how to do it first. —Preceding unsigned

comment added by 222.153.21.181 (talk) 10:49, 3 July 2008 (UTC)

Time travel, or space-time travel?

The first paragraph of this section is wrong. It is based on the assumption that the Earth does not undergo any acceleration. Its argument of relative velocity is overshadowed by the accelerations. The first acceleration is angular acceleration; the Earth is spinning. If I were to go back 12 hours in time (and ignore the other accelerations), I would end up on the opposite side; same latitude but 180 degrees difference in longitude. Not only that, the relative velocity of the place where I "started" would be 180 degrees from when I started. If I were to go back 6 months, the Earth would be on the opposite of the Sun and its velocity would be 180 degrees different. To come up with a successful argument, you would have to use general relativity, not special relativity.--Shawncorey (talk) 17:32, 16 May 2008 (UTC)

It's not correct that you need general relativity to deal with acceleration--special relativity can certainly deal with acceleration in flat spacetime where gravity is negligible, see the way SR deals with the twin paradox on this page for example. If you were standing on a spinning sphere of negligible mass, then if you take your position on the sphere when your clock reads 3:00 and your position on the sphere when your clock reads 4:00, you can certainly find an inertial reference frame in SR where both of these are the same point in space--just imagine a projectile fired from your position at 3:00 which moves at constant velocity and has just the right speed and direction so that it arrives at your position at 4:00. In the rest frame of this projectile, this means you have returned to the same position at 4:00 that you occupied at 3:00.

Of course, in the case of the Earth we do need general relativity, not because of accelerations but because of the fact that the Earth's gravity curves spacetime. However, in general relativity you are free to use arbitrary smooth coordinate systems, and the laws of physics obey the same tensor equations in all the coordinate systems, thanks to what's known as "diffeomorphism invariance" (also known as general covariance)--see this page for a discussion. So again, it would certainly be possible to find a coordinate system where your position at 4:00 is the same as your position at 3:00, even if you are standing on a spinning orbiting planet, and this coordinate system is physically no better or worse than any other in GR. Hypnosifl (talk) 22:44, 18 May 2008 (UTC)

OK, gone--Mr. Shawn H. Corey (talk) 00:54, 17 May 2008 (UTC)

Or, you could rewrite the section so that it makes better sense... instead of blanking a paragraph about a frequently-discussed issue in time travel SF, while leaving the paragraph full of cruft intact, baffling any new readers. --Yamara ✉ 02:25, 17 May 2008 (UTC)

No, I cannot.

Nor, you little worm, can you blame me for the lack of physics that agree with your imagination.

The paragraph is wrong...and it is gone.--Mr. Shawn H. Corey (talk) 04:51, 17 May 2008 (UTC)

The section is not wrong. There is no such thing as absolute space in relativity, and hence no absolute notion of which point in space at a later time is at the "same position" as a point in space at an earlier time. One can choose different coordinate systems which give different answers as to whether a given object is at rest or not (spatial coordinate not changing with time), and none is more "true" than any other in relativity. The paragraph already contains a reference for this in the form of a book by physicist Robert Geroch, if you doubt what I'm saying I suggest you read it. Hypnosifl (talk) 22:59, 17 May 2008 (UTC)

That doesn't matter. Even without an absolute reference, one might still materialize out in space, due to the fact that the earth is orbiting in an elipse, not moving in a straight line. Before you time travel, you are traveling with the earth. During time travel, will you still be influenced by the earth's gravity? Maybe/Maybe not. Who knows. It's possible that the earth will continue to be influenced by the sun and move on its orbital path, while you--the time traveler--would continue on your last known momentum, which would be a straight line. When you come out of time-travel, you will have diverged paths from the earth. This is different, than staying in an "absolute" (fixed) location during time travel, and letting the earth continue. 129.139.1.68 (talk) —Preceding undated comment was added at 19:53, 21 July 2008 (UTC)

after seeing mention of this on Wikipedia:Editor_assistance/Requests i decided to take a look, while im not an expert on relativity As the inclusion of something is based in the requirements of Verifiability and Notability, Relativity is defiantly notable and therefore comes down to is it verifiable. At first look the source appears to be reliable, but as I don`t have access to it I cant really tell, but can accept on good faith

I can't see any specific reason for its removal unless can be demonstrated that the cited source is not reliable or does not say what is stated in the article.

also the argument itself is not just dependent on relativity (general or special) but also the "method of time travel" involved and how that effects the start and end points, as ending up elsewhere makes the assumption that the time travel process does not take any such effects into account.

You might want to ask at WikiProject Relativity for someone more knowledgeable.

but as a general point stated in Verifiability wikipedia relies on is verifiability, not truth.

The threshold for inclusion in Wikipedia is verifiability, not truth—meaning, in this context, whether readers are able to check that material added to Wikipedia has already been published by a reliable source, not whether we think it is true

--Firebladed (talk) 13:51, 19 May 2008 (UTC)

Is threre a "Reader may require background on X subject to understand" template somewhere?

I've read a large amount of scientific articles including this one, that deal heavily with many concepts such as relativity and physics. In many places the article goes to and fro these subjects which can make it a bit confusing for a reader who does not have much of an understanding of the subjects (Such as myself). I know some basics about relativity, but as I do not have a college education on the subject can only guess what certain sentences mean.

I think I speak for me, and many others, when I ask if there's a template or tag we can add at the beginning of the article saying something like "Sections of this article may not be clear for readers without background knowledge of general relativity. Wikipedia has an introduction article to the subject here" just to let possible readers know that if they don't understand much of it, they need to read up more on that underlying subject. There seems to be a template for everything else from not enough sources, to wrong tone for the article. Surely it would be helpful to create one to let readers know what background information they need to understand?

And don't tell me that only people who already knew that background information would read the article, come on, the specifics of time travel can be interesting to a variety of people whether they have a degree in physics or not.

Thanks, Cody-7 (talk) 19:44, 18 July 2008 (UTC)

That would defeat the purpose--many articles would be difficult to truly understand without academic training. Bests, Languageleon (talk) 11:57, 5 October 2008 (UTC)

There is no such thing

I don't care what you here, I think there is no such time as "time traveling." It is just a figment of people's imaganation. First of all, if you understand how time works, something happens that CAN NOT BE RE DONE. Period. It is permanant. That being said, the future is being made the minute you are reading this. I don't think the future is going on RIGHT NOW. YOU are CREATING the future. —Preceding unsigned comment added by 76.120.217.110 (talk) 18:50, 19 August 2008 (UTC)

You do understand that you are simply claiming yourself as correct? What makes that so? I could go around and preach that God does not exist, no matter what you care about--Wikipedia is about preserving ideas and the philosophies behind them. I don't think you count as a reference for us to cite, either. What makes you an expert on such a matter that is so not definitive and personal without proof? Also, with modern thought, there is no creation of future nor a present. It's all the past, for each moment we consider the present is already passing, not to mention that time could be cut down to the smallest of units. If time is linear, then the future doesn't exist either. Bests, Languageleon (talk) 11:56, 5 October 2008 (UTC)

Whether it's a scientific possibility or not does not change the fact that the concept exists in people's imagination, and is widespread. Therefore the article is justified. --Bisqwit (talk) 04:30, 21 August 2008 (UTC)

An alternate time CAN also be an alternate universe.If I went back in time and killed my father before I was born.I MIGHT go to a universe where my father isn't dead,and I will be erased from my universe (unless I was already born) —Preceding unsigned comment added by 74.233.155.99 (talk) 20:21, 25 September 2008 (UTC)

You can't understand time travelling below the fourth dimension. Forget about existence. Travelling to the future is a reality. We do it all the time. We're travelling 1 second per second. Relativity is shown to increase that speed, as proven on the Voyager 1, which is about one second in the future. We cannot go years into the future because of two reasons:

• We ain't got the technology
• You'd never come back to your era, because travelling to the past is impossible, at least in the third and fourth dimensions. Memories take us to the past though. Has anyone actually noticed that? Time travelling is as real as ghosts and dreams. OK, maybe ghosts aren't real... nor dreams... it depends on what you understand for real. If "real" stucks in your old third dimension, then yes, dreams are not real.--Fluence (talk) 04:25, 1 November 2008 (UTC)

Time travel - Allah, tribes and phophecies

I have only sckimmed through all the current threads but it has occured to me that there is little (or perhaps even no) mention of time travel in relation to religous beliefs, and in particular to God. Since fictional and philosophical accounts of (potential) time travel are at least partly accounted for it would only seem fair to at least mention scriptural accounts of time, also a greater balance would be allowed for being that religous answers to questions of time can and indeed sometimes do differ from scientific responses.

Monothestic religions, and perhaps too others, beilieve that God is the creator of both time and Space, of the laws too of both time and Space, and consequently also the creator of time-space, even in its modern conception. For Muslims time travel is already possible, though not necessarily for humans - it is explicitly mentioned in the Holy Koran that since Alla is omnipresent and is able to be in all things in all times he is able to move faster than the speed of light, indeed faster than anything that it is possible for the human imagination to realise, faster even than our perception of time - it also talks in deapth in the Koran about the relativity of time as we percieve it, that what seems like a thousand years to us is only a day or less to Alla.

The greeks themselves had many gods (although given Zeus, their god of gods this is not tottaly true) and indeed they themselves had a god specifically for time itself, this god was able to appear both from the future and within it. There are, obviously, many other religous and spiritual interpretations of time travel and I would encourage anyone that feels able to summarise a general sketch of these belief systems to do so, if only for the purposes of balance.

There is a further point, though not too related, that I wished to raise, (in relation to the fiction literature), that the article mentions may refer to the earliest accounts of time travel - I would suggest, not wishing here to patronise the author, that the articles mentioned are typically white-western and show no real cultural variation, it would be laughable to think that a few European authors arround the 17th Century somehow stumbled upon such concepts as Time machines, the grandfather-paradox and other time-travel related notions - the merest glance through any well-stocked library would easily reveal discussions of time travels and references to them littered through the history books, from the Greeks to the Persians, from Prussia to the Ottoman and Turkish Empires, right through to the European and American writers. Perhaps, even arguably, time travel was known of, though is a less technically abstract way to many of the world's great ancient tribes - some aboriginal tribes, for example, smoked or consumed certain intoxicating herbs while melodically chanting, at least some of these tribes did believe that there visions were actually their spirits travelling outside of their body, so too outside of their time and space, where it has even been claimed that they were able to communicate with alien species that are yet to have evolved or that have already become exstinct. I have not here suggested that it is the case that these tibal people really time-travelled, though for all I know they may have, but it is claimed from various anthropoligists that they did believe in time-travel.

Because tribal societies did not rely on written language as we do now, or at least it would seem that some of us do, evidence of time-travel belief from pre-organised religous societies can be difficult to come across, nevertheless it should still be at least reffered to. For one last example of a tribal belief in time-travel (note, for the spirit rather than for the body) I will tell you about the Hopi tribal phrophecy, the Hopi being one of the few remaining Native Indian tribes lefty alive in the Americas: Just in the last few years it was discovered by some scientific explorers that within certain Nevada desert rocks had been hidden the tribal drawings of the Hopi tribes, pictures of white men arriving in what looked like ships, carrying crosses, pictures of cars and squared houses and even planes too, this would not have been surprising except that acheologists dated the pictures to be pre-colonial, they even dated some of the images to be older than what they reffered to. This might be seen as evidence that the Hopi Spirits really could travel forwards to view a time of the future that was to come, but a little like Scruge in Dicken's a Christmas Carol they were not physically able to interact with the future but merely to spiritually observe. I am intesrested to ask others weather they think Phrophecies and visions of these kinds should be mentioned in the article.

Sorry my comments are a little long and wordy, i am fairly new to this site! —Preceding unsigned comment added by 82.152.125.169 (talk) 13:25, 29 August 2008 (UTC)

The section "origins of the concept" is focused on the idea of backwards time travel, not on prophecies of the future or the idea that gods might perceive time passing forward at a different rate than ourselves. Also, it would help if you gave references for some of your claims, like the specific quotes from the Koran you're talking about, or the supposed pictures drawn by the Hopi of cars and planes. Hypnosifl (talk) 22:41, 10 September 2008 (UTC)

None of what you posted is necessary relevant to time travel. It is analogous to saying that in 1000 years, when the humans of the future discover our research papers on time travel and future creations, that time travel and divination were part of our society and are valid and existent. Not so. Your mention of the Hopi tribe (which seems INCREDIBLY unlikely to me as an anthropology and art history student as it would be incredibly huge news) are also not time travel, but as Hypnosifl mentioned, psychic readings. I do not think that such beliefs, regardless of whether they are Tribal American or Koranic, are valid when discussing the scientific validity of time travel. Bests, Languageleon (talk) 11:49, 5 October 2008 (UTC)

Time travel

Time is a continumm.We can "step" on any "moment" at "will". —Preceding unsigned comment added by 75.41.70.63 (talk) 17:46, 12 October 2008 (UTC)