Time Travel is Science Fiction

Discussion in 'Alternative Theories' started by Farsight, Feb 17, 2014.

  1. paddoboy Valued Senior Member

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    And really, I don't see anything in your posts, other then your passive aggressive tendencies towards me. :shrug:
    But when push comes to shove, we'll both be judged by our online peers and moderators here, will we not?
     
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  3. Undefined Banned Banned

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    When a mainstream thread invokes discussions, it necessarily demands 'counter-arguments' from BOTH 'sides' of a discussion/issue raised upon a mainstream claim that is still up for further exploration by mainstream and amateurs alike. Just because one raises counter-arguments against the mainstream claims does not make the discussion 'pseudo-science'; it makes it a discussion canvassing all current and evolving views, whether from professionals or amateurs. Period. If one prejudices discussion, then why have the discussion at all? The site would lose its raison detre', and we could all go onto Twitter/Facebook et al and do your prejudicial social media 'personal stuff' there without having to worry about scientifically based counterarguments from either 'side'. Hey?
     
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  5. Undefined Banned Banned

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    I'm here to engage in and observe scientifically based discourse on issues and ideas of interest. I would prefer to do this without all the cluttering/confusing unnecessary personal/un-argued posts which cause misunderstandings and bury the interesting bits, such that much valuable time and effort then has to be wasted on ploughing through the irrelevancies in order to follow the actual germane arguments from both 'sides' of the discussions. I don't have time to spare for wading through inconsequential clutter; and I am pretty sure I'm not the only one so time limited and disinclined to plough through clutter. It would be great if it could be kept to a minimum, is all I'm asking for. Good luck, mate!

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  7. paddoboy Valued Senior Member

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    More inane unsupported dribble, irrelevancies, lies, and revengeful attacks!
    I would ask you also to keep your own nonsense word salads to a minimum.
     
  8. Undefined Banned Banned

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    How does it go?...oh yes: "You first!"

    Then problem solved; and we won't be having these exchanges again, mate.

    Is it too much to ask you don't clutter up the threads and cheerlead other trolls who do likewise to bury/denigrate an interesting discussion they feel irrelevant to? The mods have been getting more wise to those trollish tactics for some time now; that is why the friendly suggestion you keep it to a minimum yourself. Cheers.

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  9. Russ_Watters Not a Trump supporter... Valued Senior Member

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    You're glossing over what is actually happening, even as you post a quote that tells you: The microwaves are how you see the quantum mechanical transition happening, but the transition itself is not motion in the classical sense.
    Lol, no - you don't "count... microwaves", you count transitions using the microwaves emitted when they happen. "Count...microwaves" is gibberish!
    Bla, bla, bla. Translation: "Oh, crap, I don't have an answer....um.....I guess I'll just blow it off by saying 'big deal'." Please tell me: what is moving? Again: quantum mechanical events are not motion in the classical sense. You're making a mess of this because I think you recognize you didn't consider this properly.
    Then you aren't looking hard enough. When something is moving you are watching it change position in space and change position in time. That's what the equation tells you: s=d/t. You say you cannot have time without motion? You can: (te=t2-t1). But what you can't have is motion without time.

    I notice you skipped a quote though, the part where I pointed out that you don't see space either, you only see the distance between (or length of) objects, not the space itself that they occupy. That's important because it is exactly the same issue as your complaint about not being able to see time: it is just your word-play here and not a true description of reality. It is a "flaw" that exists for both space and time (in quotes because it isn't really a flaw for either space or time).
    Wait, hold on - did you forget that you are pretending to know physics? Both of those are about philosophy! Now without you citing specific quotes from the book I can't comment on applicability, but the philosophy of presentism really isn't of any value here unless it can be used to make testable predictions. It isn't physics so it can't help you prove something in physics is wrong.
    That's extremely sloppy and probably designed to get a knee-jerk reaction of agreement, but it is wrong. We are, in fact, traveling forward in time all the time. What is not believed to be possible is:
    1. Time travel backwards.
    2. Discontinuous jumps in time.

    But by all means, post a scientific source - not a philosophical one - that agrees with you that we are not traveling forward through time and that time does not progress. The idea that you think that Einstein or Hawking or any physicist would agree with you on that is absurd at face value. Anyway, here's an article Hawking wrote on the subject:
    http://www.dailymail.co.uk/home/moslive/article-1269288/STEPHEN-HAWKING-How-build-time-machine.html

    Now he does say that a wormhole could theoretically allow you to travel backwards in time. I wasn't aware of that and I'm not sure if it is accepted, but the other two time travel methods are:
    1. Fly close to a black hole.
    2. Go really fast.
    You mean you want me to think for you. I certainly will not do your job for you.
     
  10. Farsight

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    I am not glossing this over, Russ. The second is defined from the microwaves, not the hyperfine transition itself. I was corrected on this some years ago. It's the duration of 9192631770 periods of the radiation. Not the duration of 9192631770 hyperfine transitions.

    It isn't. We're defining the second. We can't use frequency, because that's cycles per second. We count 9192631770 cycles and then we say "that's a second". And to count those cycles we sit there counting in the microwave peaks. Then the frequency is 9192631770 Hertz by definition.

    I've considered it properly. You haven't. The second is defined using the radiation. Not the hyperfine transition. Which IS motion in the classical sense.

    Motion is empirical Russ. You can sit and watch something change position in space. You can see it happening. You can point to one position or another. But when you point to a "position in time" all you're doing is pointing to a clock. And to the position of its hands. In space.

    If I skipped anything it was only for brevity. It's no flaw. You can see a space. You can see a gap. Again it's empirical. On the London Underground, on certain stations where the platform is curved, the tannoy says Mind the gap. That gap is there. You can see the gap, the space between your position1 and position2.

    Yes. I know an awful lot of physics Russ.

    The important point is that all this isn't some "my theory" stuff. I'm telling you about things you don't know about. Not pushing some pet idea.

    Continued.
     
  11. Farsight

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    3,492
    Re the mainstream scientific view is that time travel is science fiction.

    It isn't wrong. And we are NOT travelling forward in time. That's just a popscience figure-of-speech. Read the OP again. Pay attention to the stasis box, which is an idealised freezer, like an easy version of GR time dilation. You "travel" to the future by not moving whilst everything else does. And the motion is through space.

    And if you read the OP you'll understand why. You can't travel backwards in time because you don't even travel forwards in time.

    The scientific source is the evidence you can see, which I refer to in the OP. I also refer to Einstein to support my case, and I referred to that Hawking article. See paragraph 4. Follow the hyperlink on Hawking.

    No it isn't. A lot of what Hawking says isn't accepted. A lot of physicists think he's a celebrity quack who deliberately specialises in speculative hypotheses that cannot be disproven. See this physicsworld article to get a flavour of that: http://physicsworld.com/cws/article/indepth/2011/apr/20/taking-the-multiverse-on-faith

    These are examples of GR and SR time dilation. There's no issue with time dilation. But it isn't time travel. Again, read the OP. You could achieve the same result with a freezer.

    No, I mean think for yourself.
     
  12. Farsight

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    Well said that man.
     
  13. Secret Registered Senior Member

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    EDIT: Please replace all instance of "time travel" with "time travel to the past"

    I agree that the spacetime manifold is, in a nutshell, a mathematical abstraction of whatever reality is truly is (for the purpose of doing calculations and predictions). But like all models in science, if it matches the experimental findings (such as GPS, the Gravity Probe B experiment, Bending of light from distant stars by the sun, the Michaelson Moray interferometer experiment etc.) and provide good explanations, then it is supported (but not necessary the full picture) and should there is at least one observation that is at odds with the theory, then it would be shot down or modified to account for it.

    A closed timelike curve (CTCs) is one of the weird things predicted by this model (General relativity). Like what you said, there is currently no evidence that these (not in the math abstraction describe here, but as some phenomenon that can be model by said math abstraction) exist in some form. However there are also no known evidence that can rule them out (as mentioned in the Stanford time travel link, if using general relativity, then theoretically whatever structure that is mathematically represented as CTCs are not only possible but quite commonplace. However this does not mean they exist. Theoretically possible does not imply they are actually there.

    As for time, there are two prevailing camps about the philosophy of time, one is eternalism (the one used in general relativity and special relativity, modelling space and time as one single mathematical space known as spacetime, and that past present and future exists) and presentism (That the only time is now and that past and future are not there), the one that is basically the idea in the OP.

    I guess the reason why some mainstream physicists will analyse about time travel is because they are predicted by the models and yet we cannot (have not?) found any way that any known laws of physics can rule it out, thus is it likely to be possible and worth investigating about it's theoretical implications (i.e. how it may work if it is there). It's just like how 10 years ago physicists think those who proposed extra dimensions are crank, bogus ideas, but nowadays they embraced the idea because of how it can possibly account for a lot of phenomenon and simplify the maths. This, however does not mean they necessary exist in reality and the experimental guys are still trying to search for them via the high energy experiments

    The problem of eternalism, IMO, is that I have no idea how it can give rise the daily experience that time has passed/elapsed as everything on it is basically static and already there since day 1. Presentism, despite how it agrees more on our daily intuition and experience, will require that they is an objective existence of time, but we still have no idea whether time is something intrinsic or an emergent phenomenon EDIT: I realise I do not understand presentism enough to give any sensible comment on it, thus see below

    http://en.wikipedia.org/wiki/Presentism_(philosophy_of_time)

    I remember back in the Time is Dead thread Aqueous Id mentioned how change can be brought about without a change in time, for example the gradient function, which measures how the function value changes with the position. I actually carry a simialr view as yours regarding about time because I just don't get what "change of time" means (so to speak), i.e. for the gradient example, the function value will differ because you go to another position, this result is easily visualise and can be related to something physical (like how we can infer space by the distance between two objects), But for things like velocity (displacement per unit time), what physically detectable or tangible thing is changing that result in the change in displacement (separation between two things)?

    This is why I sometimes got confused about clocks.
    Clocks use periodic changes in events (not necessary motion, as the atomic clock example demonstrates) to count other events of interest, and this is how time is measured. But what causes those periodic changes, and since clocks are measuring time via counting events, then what does those periodic changes are changing w.r.t. and why are they changing in the first place? (The scenario is like the gradient function, but what is that parameter in that is corresponding to position in the gradient function, since given how clocks measures time by counting events, time itself cannot be the parameter?. That is, given clocks count events by using change in periodic events per unit of <WHAT>?

    Yes, that is precisely what I learnt in uni, although 2 seemed to be a generalised version of 1.
    But sometimes, I am wondering whether time is just a function of entropy. Given how physicists treat time as a physical (hence real) parameter, how will time be measured in the heat death, or does time has an independent meaning without the notion of entropy and the 2nd law? (where entropy is maximized?) (No, do not quote the spacetime crystal findings, as the jury is still out for that one)
    Me sharing this viewpoint of yours is why I get confused about some recent theories in these 5 years which can completely remove the time parameter from known physics equations. Because if what those theories said is true (that time does not exist, time is an illusion, time is emergent phenomenon, or time is unecessary), then what caused motion?

    (This question to others as well) But in such model (or abstraction), does time actually elasped, or is it as what you mentioned, it is just another parameter that is not changing by itself (like how the plate does not actually sponteneously rises (I hope I understood this properly)?

    For far fetched ideas like these (the recent theoretical physicist's theories about black holes and entanglement,, and etc.) and are not known to violate or contradict any known laws of physics or past experimental findings, experiments will carry the burden of proof. Until then I will just crossing my fingers and see where they lead to

    View attachment 6882

    Just read from Casual Relationship and the light cone, I understood how the light cone defines causality. But looking at the light cone picture above, no events are moving w.r.t. each other. They are like static points in the spacetime manifold. From a lecture note, I learnt how the norm of a timelike curve gives the proper time, which is the time measure w.r.t to an observer as he/she moves from one event to another along the timelike curve. But I don't understand how this give rise to the notion of "time elapsed" (that is, how we seemed to know that time has passed, as in the spacetime diagram, all events are just static points in the diagram, and they don't actually "move/progress forward in time", given how time itself is already a dimension in the spacetime diagram? (setting aside the issue that spacetime is a mathematical abstraction for the moment since in general relativity we use this model to understand how things behave in reality, and it's currently the best model to understand gravitation)) (NB The answer to this bolded question may help me to better understand relativity since I am still kinda preliminary on it and I mostly self learnt form that lecture notes)

    Tl.dr:
    Focus only on the bolded question if this is the case
     
  14. Farsight

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    Noted. I "root for relativity", and I'm fond of quoting Einstein.

    Agreed. I'd say the issue here is one of interpretation. Some will say "General Relativity predicts X", when X was not predicted by Einstein, but by somebody else, and then misrepresented. If you look at CTCs on wikipedia you can find a reference to Gödel. But see the OP, and note my reference to A World without Time: The Forgotten Legacy of Gödel and Einstein.

    Good man, Secret. Relativity is usually associated with eternalism, but A World without Time is a associated with presentism.

    Continued.
     
  15. Farsight

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    I'd say that in recent years we've seen "woo" peddled by celebrity physicists so much that it's gained a veneer of respectability, at least in popscience outlets.

    Nobody is searching for time travel.

    I would say this: we can see a gap, a space, and we can see motion. We can't see time flowing, or light cones or worldlines or spacetime.

    Yes. You change. You move. There's always some kind of change or motion involved.

    An object moves. It changes its position in space. And that's empirical.

    An atomic clock does use motion. It employs the hyperfine spinflip which is a "turnover" electron motion, and the motion of the resultant microwaves.

    Things move. Sh*t happens.

    Entropy is just sameness. People talk about it as if it's something primal and fundamental that exists in its own right. But it doesn't.

    The big bang. Something broke. As to what, I don't know.

    Continued.
     
  16. Farsight

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    The plate doesn't actually rise, and time doesn't actually pass or elapse or flow. Things move through space. That's it.

    I think there's more "woo" presented as bona-fide physics than when I was a kid.

    Spacetime is static. The observer doesn't move through spacetime from one event to another. S/he moves through space, and meanwhile his/her clock is clocking up some kind of regular cyclical motion within that clock.

    Well spotted. Have a look at this:

    Nasty Little Truth About Spacetime Physics.

    There's some names that don't deserve to be in his list, but he is essentially right. There is no motion in spacetime, or through spacetime. Or through time either. Things move through space, even things inside clocks.
     
  17. paddoboy Valued Senior Member

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    Ahhh, here we go again..."Hey everyone, Look at me!...

    All you have posted in nonsense and red herrings as this thread is.
    Again, everyone knows that time travel is science fiction. That doesn't mean its impossible.

    Einstein used the analogy of time being a river fast flowing with eddies and whirlpools, as opposed to the Newtonian analogy of being like an arrow shot from a bow.
    Most of today's reputable scientists realize that time travel is theoretically possible, at least to the future....and possibly even to the past.
    The theoretical creation of new time lines can cancel out the Grandfather paradox.

    To those that see time as purely abstract and lacking reality, they should realize that it’s a silly question. The reality of anything is only an interesting issue if its a well-defined concept whose actual existence is in question, like fairies and goblins.

    Time exists, primarily as a unified concept with space/time, which can be, and has been measured.

    Even in the study of QG, it has been shown that our 4D space/time is real and not just emergent.
    I firmly hold that, contrary to the ancient philosophical concept of time, it is not only real, but it is likely that it is the only aspect of reality we experience directly that is fundamental and not emergent from anything else.

    If the Universe stopped expanding, would time stop? NO....
    If the Universe started a contracting phase, would time stop? again NO.

    "Experiments continue to show that there is no 'space' that stands apart from space-time itself...no arena in which matter, energy and gravity operate which is not affected by matter, energy and gravity. General relativity tells us that what we call space is just another feature of the gravitational field of the universe, so space and space-time can and do not exist apart from the matter and energy that creates the gravitational field. This is not speculation, but sound observation."

    The above quote was first uttered in answer to questions in "Astronomy Cafe"by Sten Odenwald.

    I don't know what the future holds, but I am confident given time, we can achieve all that is allowed by the laws of physics and GR.
     
  18. river

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    Pad

    Why
     
  19. paddoboy Valued Senior Member

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    Controversially, Physicist Argues Time Is Real :


    In a conversation with Duke University neuroscientist Warren Meck, theoretical physicist Smolin, who's based at Canada's Perimeter Institute for Theoretical Physics, argued for the controversial idea that time is real. "Time is paramount," he said, "and the experience we all have of reality being in the present moment is not an illusion, but the deepest clue we have to the fundamental nature of reality."


    Smolin said he hadn't come to this concept lightly. He started out thinking, as most physicists do, that time is subjective and illusory. According to Albert Einstein's theory of general relativity, time is just another dimension in space, traversable in either direction, and our human perception of moments passing steadily and sequentially is all in our heads.

    Over time, though, Smolin became convinced not only that time was real, but that this notion could be the key to understanding the laws of nature.

    "If laws are outside of time, then they're inexplicable," he said. "If law just simply is, there's no explanation. If we want to understand law … then law must evolve, law must change, law must be subject to time. Law then emerges from time and is subject to time rather than the reverse."

    Smolin admitted there are objections to this idea, especially what he calls "the meta-law dilemma:" If physical laws are subject to time, and evolve over time, then there must be some larger law that guides their evolution. But wouldn't this law, then, have to be beyond time, to determine how the other laws change with time? Other physicists have cited this objection in reaction to Smolin's work.

    "The problem I see with the argument for laws that evolve in time is one that you yourself identify in the book: what you call the 'meta-laws dilemma,'" Columbia University physicist Peter Woit wrote on his blog Not Even Wrong. "You speculate a bit in the book on ways to resolve this, but I don't see a convincing answer to the criticism that whatever explanation you come up with for what determines how laws evolve, I’m free to characterize that as just another law."

    Smolin admitted this is currently a sticking point, but maintained that there are possible solutions.

    "I believe you can resolve the meta-law dilemma," Smolin said at the Rubin event. "I think the direction of 21st-century cosmology will depend on the right way to resolve the meta-law dilemma."

    Smolin and Meck discussed the consequences of his idea, including what it means for our understanding of human consciousness and free will. One implication of the idea that time is an illusion is the notion that the future is just as decided as the past.

    "If I think the future's already written, then the things that are most valuable about being human are illusions along with time," Smolin said. "We still aspire to make choices in life. That is a precious part of our humanity. If the real metaphysical picture is that there are just atoms moving in the void, then nothing is ever new and nothing's ever surprising — it's just the rearrangement of atoms. There's a loss of responsibility as well as a loss of human dignity."


    http://www.livescience.com/29081-time-real-illusion-smolin.html


    Einstein did of course later in life alter his view of time, and that has been quoted elsewhere and in the BH thread.
     
  20. river

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    If time is real then time must have a efficacy , in and of its self

    Therefore the real problem or question what is the essence of this efficacy of time

    Until this is answered this concept that time real , is nonsense
     
  21. paddoboy Valued Senior Member

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    No more nonsensical then your trolling posts, of which you have a record of here.
    But anyway, I'll give you the benefit of the doubt this time......

    Time is a measure of change. Even if the universe doesn't expand, we see changes all about that aren't tied to that expansion. Therefore we can say that change will occur and so will time.
    Time is also inexorably linked with entropy.
    And of course the static Universe Einstein first adhered to, still had time.

    If we had no time, everything would happen together....
    If we had no space, everything would be together.
     
  22. river

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    what is the cause of change ?
     
  23. paddoboy Valued Senior Member

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    Please take the time to read the first couple of sentences in my previous post.
     

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