does time travel?

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Originally Posted by YesNo

I think you said you had some blog posts somewhere on the topic. That might clarify your position for me.

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My blog is here on Litnet. http://www.online-literature.com/forums/blog.php?4509

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It occurred to me that should you go into a many worlds time machine, decide to press the button, you would split the current universe into at least two universes, one where you stay in the current universe and the other where you go into a different past universe splitting it in the process. So you don't have to worry about coming back to the home universe. You never left it.

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You are starting to understand why there is an infinity of universes. It gets even worse when one thinks about the future.

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Originally Posted by MorpheusSandman

Right, but I'm not getting how you think that relates to free-will...

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That's simple. One can make decisions that are independent and give the appearance of being freely made; although like everything they will be determined by cause and effect, but because all possible decisions are said to be made in effect there is free will.

No, the theory (actually interpretation) says that each world is already present in the wavefunction and something like a "decision" would be a point of "decoherence" where the already-present worlds split from each other. This isn't "creation" of new worlds, it's the "decoherence" of worlds that are already there. Think of it as a zipper: both sides of the zipper are already there, and you wouldn't say that the act of unzipping "creates" a new zipper, but that it detaches the two zipper halves that were there.[/QUOTE]

Your analogy is not correct. There would be point A in which universe A exists. Then there would be decision point B where there would be decoherence B. Then ere would be time C in which there would be universe A in which decision B was not made, and there would be universe B in which decision B was made. The two universes would be complete and inaccessible from the other. While the origin of universe B is in the earlier universe A, there was a point when universe B started to exist. First there was one; then there were two.

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Originally Posted by Jack of Hearts

What free probably meant-- and you aren't going to like this either-- is that time, being perceived by the senses, is only posited by consciousness.J

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You are mistaken. Time is separation between events. If there were no time, then everything would be happening simultaneously.

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Originally Posted by PeterL

You are starting to understand why there is an infinity of universes. It gets even worse when one thinks about the future.

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Except AFAIK, infinity is strictly a mathematical concept that doesn't apply to physical reality. There's a finite amount of matter in the universe, for example; it's just a very large number.

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Originally Posted by Calidore

Except AFAIK, infinity is strictly a mathematical concept that doesn't apply to physical reality. There's a finite amount of matter in the universe, for example; it's just a very large number.

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Think what you like.

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Originally Posted by PeterL

That's simple. One can make decisions that are independent and give the appearance of being freely made; although like everything they will be determined by cause and effect, but because all possible decisions are said to be made in effect there is free will.

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This just sounds like gobbledygook to me. It vaguely sounds like you're supporting the compatibalist version of free-will that states that even if our choices are determined, because we can not know the full causes and effect beforehand our choices will still feel free to us.

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Originally Posted by PeterL

Your analogy is not correct. There would be point A in which universe A exists. Then there would be decision point B where there would be decoherence B. Then ere would be time C in which there would be universe A in which decision B was not made, and there would be universe B in which decision B was made. The two universes would be complete and inaccessible from the other. While the origin of universe B is in the earlier universe A, there was a point when universe B started to exist. First there was one; then there were two.

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This is quite wrong. The entire POINT of the wavefunction is that, mathematically, every option is contained within the formula. When we observe it, ie when two quantum states interact, we experience only one of those possibilities. So, to correct your explanation, there is point AB in which universe A and B co-exist in a single universe. There is decision point C where there is decoherence C, and, after that decoherence, we get a separated world for both A and B. Obviously there will always be before-C in which A and B are AB, but once the decision is made, A and B are mutually inaccessible. You seem to be assuming that "not making decision C" means that new-world B is created, but this is incorrect. "Not making decision C" would actually be one of the possibilities of decision C. So we can rephrase this as having point ABC in which A is making decision with option 1, B is making decision with option 2, and C is not making the decision between option 1 and 2. The act of not making that decision is still a decision, and would split the ABC point into World A, World B, and World C.

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Originally Posted by Calidore

Except AFAIK, infinity is strictly a mathematical concept that doesn't apply to physical reality. There's a finite amount of matter in the universe, for example; it's just a very large number.

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hi Calidore. infinity is a number. finity however is not.

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Originally Posted by MorpheusSandman

This just sounds like gobbledygook to me. It vaguely sounds like you're supporting the compatibalist version of free-will that states that even if our choices are determined, because we can not know the full causes and effect beforehand our choices will still feel free to us.

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It is similar, and it may simply be a different way of thinking about it. I would still contend that umtilately everything is determined.

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This is quite wrong. The entire POINT of the wavefunction is that, mathematically, every option is contained within the formula. When we observe it, ie when two quantum states interact, we experience only one of those possibilities. So, to correct your explanation, there is point AB in which universe A and B co-exist in a single universe. There is decision point C where there is decoherence C, and, after that decoherence, we get a separated world for both A and B. Obviously there will always be before-C in which A and B are AB, but once the decision is made, A and B are mutually inaccessible. You seem to be assuming that "not making decision C" means that new-world B is created, but this is incorrect. "Not making decision C" would actually be one of the possibilities of decision C. So we can rephrase this as having point ABC in which A is making decision with option 1, B is making decision with option 2, and C is not making the decision between option 1 and 2. The act of not making that decision is still a decision, and would split the ABC point into World A, World B, and World C.

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We do not disaggre in principle, but I would say that in the original state there was a single universe A, and B and C are children of A. Yes, they were A, but that was a single thing; it was not ABC. When B and C came ito existence their histories were the history of A up to the decision point.

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Originally Posted by PeterL

Yes, they were A, but that was a single thing; it was not ABC. When B and C came ito existence their histories were the history of A up to the decision point.

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I think we're pretty close to agreement, but a few details need ironing out. B and C don't "come into existence" any more than A "comes into existence" because prior to the decision all three were already co-existing. Let's try it this way: You have World A which reaches Decision B, within Decision B are Worlds C, D, and E. Once the decision is made, C, D, and E ALL separate from A, even though they share A as a common history. In a sense, World A doesn't exist exist anymore because World A was a world in which C, D, and E co-existed. After decision B; C, D, and E split, but they don't really "come into existence," they aren't "created," they were already THERE.

I don't mean to be persnickety about this, but the idea that MW "creates new worlds" is one thing that leads laymen to assume that this would violate the conservation of energy. However, if all the worlds are already there and that they're merely separating at decoherence points, then there's no violation.

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Originally Posted by PeterL

You are mistaken. Time is separation between events. If there were no time, then everything would be happening simultaneously.

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No. You can't read-- or more likely, choose not to. The statement's only assertion (you can read it, it's still there, unedited) was in regards to interpreting what the poster called free meant.

It could very well be the case that Jack of Hearts is mistaken about interpreting free's input. But you didn't respond to that. In an act of sophistry and belligerence, you asserted that he was 'mistaken.' The other sentences in your post have to be regarded as non-sequitur or taken with the implication that Jack of Hearts was asserting that time did not exist.

... which he didn't. You, PeterL, know nothing of what this poster thinks about time; and he wouldn't bother to discuss it with you, because your constructs are rife with intellectual laziness and ill will. They always have been, which is why these little peck-a-dillos dot your interaction record here:

http://www.online-literature.com/for...ism&highlight=

http://www.online-literature.com/for...ing&highlight=

It's not coincidence.






J

~

W a r n i n g

Please do not personalise your arguments.

Such posts will be removed without further notice.

~

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Originally Posted by Jack of Hearts

No. You can't read-- or more likely, choose not to. The statement's only assertion (you can read it, it's still there, unedited) was in regards to interpreting what the poster called free meant.

It could very well be the case that Jack of Hearts is mistaken about interpreting free's input. But you didn't respond to that. In an act of sophistry and belligerence, you asserted that he was 'mistaken.' The other sentences in your post have to be regarded as non-sequitur or taken with the implication that Jack of Hearts was asserting that time did not exist.

... which he didn't. You, PeterL, know nothing of what this poster thinks about time; and he wouldn't bother to discuss it with you, because your constructs are rife with intellectual laziness and ill will. They always have been, which is why these little peck-a-dillos dot your interaction record here:

http://www.online-literature.com/for...ism&highlight=

http://www.online-literature.com/for...ing&highlight=

It's not coincidence.


J

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An ad hominem (Latin for "to the man" or "to the person"[1]), short for argumentum ad hominem, is a general category of fallacies in which a claim or argument is rejected on the basis of some irrelevant fact about the author of or the person presenting the claim or argument.[2] Ad hominem reasoning is normally categorized as an informal fallacy,[3][4][5] more precisely as a genetic fallacy,[6] a subcategory of fallacies of irrelevance.[7]
http://en.wikipedia.org/wiki/Ad_hominem

See also: http://www.online-literature.com/for...-Really-Trying

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Originally Posted by MorpheusSandman

I think we're pretty close to agreement, but a few details need ironing out. B and C don't "come into existence" any more than A "comes into existence" because prior to the decision all three were already co-existing. Let's try it this way: You have World A which reaches Decision B, within Decision B are Worlds C, D, and E. Once the decision is made, C, D, and E ALL separate from A, even though they share A as a common history. In a sense, World A doesn't exist exist anymore because World A was a world in which C, D, and E co-existed. After decision B; C, D, and E split, but they don't really "come into existence," they aren't "created," they were already THERE.

I don't mean to be persnickety about this, but the idea that MW "creates new worlds" is one thing that leads laymen to assume that this would violate the conservation of energy. However, if all the worlds are already there and that they're merely separating at decoherence points, then there's no violation.

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I know what you mean A, B, and C have the same history, but there was only one, until the decision. I don't disagree, but I don't like saying that 3=1 or other such mathematical oddities.

The conservation of mass and energy are two reasons why many physicists do not accept MWI: SHAZAM! Suddenly there is three times as much mass as there was a while ago. If you are saying that they completely existed before, then the decision was inconsequential.

I don't want to go into it, but I think there is a way around this, and I think that it has already been proposed, but I haven't found the article.

Again, silly PeterL, you know not with what you play. This reader didn't attack your 'argument' or 'conclusion' through any slight on you. There was no claim or conclusion in the realm of ad hominem-- just reasoning structures (that don't pertain to the argument at hand), followed separately by a normative opinion about why Jack of Hearts holds the belief that interacting with you is the virtual equivalent of watching cable news and therefore not worth serious effort.

So you've demonstrated 1) that you don't know what ad hominem is, and 2) a very specific style of communication that approximates being 'discussion' on a superficial level but is in reality just a subversive form of narcissism.

By erroneously claiming that an 'ad hominem' fallacy made Jack of Hearts' reasoning invalid (again, it didn't commentary on you personally followed after and outside of the reasoning structures, pay attention), you've sidestepped any actual dialogue concerning any issue at hand so that you could 'win' the argument. So--

way to pull out the win, buddy.




J

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Originally Posted by cacian

when I think time travel I thing forward never backward.

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I agree.

A forward travel through time is what we do by living. Going backward into time doesn't make sense. It would mean there is something to go backward into, but what is that past time but memories? Remembering the past is all the time travel into the past that we would be able to achieve.

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Originally Posted by YesNo

I agree.

A forward travel through time is what we do by living. Going backward into time doesn't make sense. It would mean there is something to go backward into, but what is that past time but memories? Remembering the past is all the time travel into the past that we would be able to achieve.

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agreed another word comes to mind and that is nostalgia. I hear it a lot when people refer to remembering past time.
I think memory is ''remembering what was''. time is different. it is forward because it is updating to go back would suggest time would date as in dated which could not be the case. time updates itself rather debate itself.
human ages as they go through time if they did not that would mean time travelled back. age is the reason why time goes forward.

Aging is a form of entropy, directed change. The idea of time "updating" as you mention, or rather, change updating makes sense. Change doesn't update itself, it is just more change, always forward.

Upon waking this morning it occurred to me that "space-time" is mistakenly considered real, a substitute for the rejected ether. Although in the formulas used in physics containing a t, standing for time, one could put in a negative t to get a backward prediction, this doesn't mean there is something real called time we could move into in any direction we please.

Those formulas only work as models of reality. What is out there for space are energy fields and what represents time is relative change among objects within those fields. What Einstein did was link energy fields with changing frames of reference.

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Originally Posted by YesNo

Aging is a form of entropy, directed change. The idea of time "updating" as you mention, or rather, change updating makes sense. Change doesn't update itself, it is just more change, always forward.

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ageing is as a result of time moving forward and updating ie the more we age and the more time we have in fact consumed in terms of changes. it is reflected on us because we humans are evolving around its changes/updating and the way we express the changes is through growing old. time does not add or surplus it moves in a formula of constant but changing/moving forward I think.
if you take the example of the desert and the way the wind builds up streaks or tiny dunes because the movement shifts forward in a constant but updating way because it goes forward then comes back. the desert does not move but the wind does.
the streaks could be compared to ageing and desert to a human who is exposed to time.

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Upon waking this morning it occurred to me that "space-time" is mistakenly considered real, a substitute for the rejected ether. Although in the formulas used in physics containing a t, standing for time, one could put in a negative t to get a backward prediction, this doesn't mean there is something real called time we could move into in any direction we please.

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I do not believe there is an ether. the reason for that is that I can only believe in what I can perceive see or feel.

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Those formulas only work as models of reality. What is out there for space are energy fields and what represents time is relative change among objects within those fields. What Einstein did was link energy fields with changing frames of reference.

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I do not understand energy fields and what they are about. space is energetic because of the planets including earth and humans. we are energy and what surrounds us immediately is what activates the energy within us. energy can only work both ways . it need give and take it circular in that sense. energy is activated upon another sourced one. humans are one source of energy light is another.

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Originally Posted by YesNo

Upon waking this morning it occurred to me that "space-time" is mistakenly considered real, a substitute for the rejected ether.

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All of the predictions of relativity, both special and general hold true in Aether Theory, and there are some predictions of Aether that aare true but are not predicted by relativity. The Michelson-Morley experiment was repeated many times, and was found that there is aether drift, but it is different from what the theory predicted. Dayton Miller was one of the more noted people in the field, but there have been others sinece then who have found more evidence for Aether theory.
You might start from this article:

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

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Although in the formulas used in physics containing a t, standing for time, one could put in a negative t to get a backward prediction, this doesn't mean there is something real called time we could move into in any direction we please.

Those formulas only work as models of reality. What is out there for space are energy fields and what represents time is relative change among objects within those fields. What Einstein did was link energy fields with changing frames of reference.

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Nearly all physical processes are reversible (I can't recall the one that isn't), and that may indicate that everything is actually reversible. Yes, reversing an atomic process is not the same as sending me back to 20,000 BCE, but the principal is the same.

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Originally Posted by PeterL

I don't like saying that 3=1 or other such mathematical oddities.

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That "mathematical oddity" is what is within the Schrodinger Wave Equation, so it's not me saying that "3=1," it's the math.

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Originally Posted by PeterL

The conservation of mass and energy are two reasons why many physicists do not accept MWI: SHAZAM! Suddenly there is three times as much mass as there was a while ago. If you are saying that they completely existed before, then the decision was inconsequential.

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Yes, and those that don't accept it for those reasons are wrong because nothing new is being created. You seem to share this misunderstanding with them. You don't have "three times as much mass," you have a single mass split (to use our example) three ways. I don't know why you say "the decision was inconsequential if they existed before," because even though they existed they couldn't be experienced distinctly until the decision was made. This is Schrodinger's Cat; until we look into the box, the cat is alive AND dead, and our looking eliminates the "and" and splits between one ALIVE world and one DEAD world.

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Originally Posted by MorpheusSandman

That "mathematical oddity" is what is within the Schrodinger Wave Equation, so it's not me saying that "3=1," it's the math.

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It strongly suggests that there is something wrong with the math.

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Yes, and those that don't accept it for those reasons are wrong because nothing new is being created. You seem to share this misunderstanding with them. You don't have "three times as much mass," you have a single mass split (to use our example) three ways. I don't know why you say "the decision was inconsequential if they existed before," because even though they existed they couldn't be experienced distinctly until the decision was made. This is Schrodinger's Cat; until we look into the box, the cat is alive AND dead, and our looking eliminates the "and" and splits between one ALIVE world and one DEAD world.

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Sorry, but the problem of Schrodinger's Cat was eliminated by MWI. The cat is alive in some worlds and dead in other worlds, but it is one or the other. There was only one cat, and it was bifurcated, along with the rest of the world. There was one, and now there are two. Our looking doesn't change anything; the cats were dead and alive respectively from the time the box was closed.

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Originally Posted by PeterL

It strongly suggests that there is something wrong with the math.

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Based on what?

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Originally Posted by PeterL

Sorry, but the problem of Schrodinger's Cat was eliminated by MWI. The cat is alive in some worlds and dead in other worlds, but it is one or the other. There was only one cat, and it was bifurcated, along with the rest of the world. There was one, and now there are two. Our looking doesn't change anything; the cats were dead and alive respectively from the time the box was closed.

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Our looking changes how we interact with other quantum entities; even if we assume that there is a dead-cat world and alive-cat world before we look, we don't know what world we're in until we look, so we "experience" the cat as "alive and dead." This is the same thing with particles. When we're not measuring them, they display the quality of existing in all possible states at once. Once we look, they behave like ordinary matter, one thing or another, not everything simultaneously. In Schrodinger's Cat, the cat is like a particle until we look. This is because we ourselves, as quantum entities, become entangled with other quantum entities. So while our observation is not a "cause" of anything (it doesn't affect the cat), it very much affects how we experience the cat. So, while MW has an answer to what's happening with Schrodinger's Cat, I wouldn't say it "eliminates the problem" (if it even ever was a problem, since it was merely meant to illustrate our observations of particle behavior on a macro level).

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Originally Posted by MorpheusSandman

Based on what?

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Newtonian physics.

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Our looking changes how we interact with other quantum entities; even if we assume that there is a dead-cat world and alive-cat world before we look, we don't know what world we're in until we look, so we "experience" the cat as "alive and dead." This is the same thing with particles. When we're not measuring them, they display the quality of existing in all possible states at once. Once we look, they behave like ordinary matter, one thing or another, not everything simultaneously. In Schrodinger's Cat, the cat is like a particle until we look. This is because we ourselves, as quantum entities, become entangled with other quantum entities. So while our observation is not a "cause" of anything (it doesn't affect the cat), it very much affects how we experience the cat. So, while MW has an answer to what's happening with Schrodinger's Cat, I wouldn't say it "eliminates the problem" (if it even ever was a problem, since it was merely meant to illustrate our observations of particle behavior on a macro level).

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Schrodinger's Cat demonstrated uncertainty. The uncertainty no longer exists. There is no need to look to see whether the cat is alive or dead; it is alive in one universe and dead in another.

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Originally Posted by PeterL

Newtonian physics.

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Newtonian physics is wrong. It's a mere approximation that couldn't even account for the orbit of Mercury. General Relativity is better yet, but even it can't account for quantum events. Quantum math can scale to GR's levels, though (minus gravity). Its minute accuracy is reason enough not to doubt it. But saying "Newtonian physics" as a reason for doubting Quantum math is rather laughable.

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Originally Posted by PeterL

Schrodinger's Cat demonstrated uncertainty. The uncertainty no longer exists. There is no need to look to see whether the cat is alive or dead; it is alive in one universe and dead in another.

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The uncertainty was always on the observer's (our) side, so it still exists until the observer looks. The only thing the observer can say for certain is that both the alive and dead worlds are real (because possible) and they will find themselves in one or the other once they look. You're making a similar mistake to those that Copenhagen makes, and that's taking the observer out of the equation. Even if the observer doesn't effect the world the object ends up in (as in Copenhagen, who also denies the reality of the other worlds), the observer does effect how the observer ends up in each world.

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Originally Posted by cacian

I do not believe there is an ether. the reason for that is that I can only believe in what I can perceive see or feel.

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I don't believe in it either.

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Originally Posted by cacian

I do not understand energy fields and what they are about. space is energetic because of the planets including earth and humans. we are energy and what surrounds us immediately is what activates the energy within us. energy can only work both ways . it need give and take it circular in that sense. energy is activated upon another sourced one. humans are one source of energy light is another.

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Space would be some relationship between objects which generate fields and time would be the change of those objects. I don't understand energy fields either. I was trying to get away from thinking that space-time is something real rather than just a coordinate system for a formula to use.

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Originally Posted by PeterL

All of the predictions of relativity, both special and general hold true in Aether Theory, and there are some predictions of Aether that aare true but are not predicted by relativity. The Michelson-Morley experiment was repeated many times, and was found that there is aether drift, but it is different from what the theory predicted. Dayton Miller was one of the more noted people in the field, but there have been others sinece then who have found more evidence for Aether theory.
You might start from this article:

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

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Looking at the link, it seems that Shankland could not confirm Miller's results suggesting there were some kind of ether. However, I think it is worth testing physical constants to see just how constant they are. Ultimately that might bring up the notion of an ether indirectly.

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Originally Posted by PeterL

Nearly all physical processes are reversible (I can't recall the one that isn't), and that may indicate that everything is actually reversible. Yes, reversing an atomic process is not the same as sending me back to 20,000 BCE, but the principal is the same.

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I assume you would accept that our lives are physical processes going from birth to death. Are they reversible (outside of some science fiction tale)?

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Originally Posted by YesNo

Looking at the link, it seems that Shankland could not confirm Miller's results suggesting there were some kind of ether. However, I think it is worth testing physical constants to see just how constant they are. Ultimately that might bring up the notion of an ether indirectly.


I assume you would accept that our lives are physical processes going from birth to death. Are they reversible (outside of some science fiction tale)?

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Our lives involve chemical processes too, which are not always reversible.

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Originally Posted by Volya

Our lives involve chemical processes too, which are not always reversible.

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That's a good point. There are physical/chemical changes (processes) that are considered to be either reversible or non-reversible, depending
on the laws of thermodynamics applied to specific situations. The Second Law of Thermodynamics states that the global (i.e. system and its
surroundings) change in entropy of any spontaneous process is greater than or equal to zero. It's never a negative number.

In most situations entropy increases because there is some loss of "useful" energy that is "wasted" in the form of "heat" dissipation. In
mechanical systems, for example, energy is lost through friction. This is a major reason why we haven't been able to make "perpetual
motion" machines. The best that we can hope for in spontaneous physical processes is zero total entropy change. We can't expect that
it will be possible for a physical process to decrease total entropy. It is possible to have a LOCAL decrease in entropy, but this will always
come at a cost of TOTAL (i.e. "universal") entropy. Maxwell described a famous thought experiment, "Maxwell's Demon," that proposed
a plausible way to violate the Second Law. There has been a lot of discussion about why the Demon could not do what he was tasked to
do (i.e. violate the Second Law).

One of the reasons why so many folks believe that the Second Law explains the "unidirectionality" of time is that the 2nd Law states that
entropy is always greater than or equal to zero.

systems

What would a spontaneous physical process with zero total entropy change be? Perhaps the earth's motion around the sun? I assume a reversible physical process would have to have zero total entropy change.

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Originally Posted by YesNo

What would a spontaneous physical process with zero total entropy change be? Perhaps the earth's motion around the sun? I assume a reversible physical process would have to have zero total entropy change.

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You ask about two different things: 1) spontaneous processes; and, 2) reversible processes. Spontaneous processes are those for which the Gibbs Free Energy, defined by the equation deltaG=deltaH-TdeltaS is negative. G=Gibbs Free Energy, H=enthalpy, T=temperature, and S=entropy....and delta="change in." Reversible processes are those for which the change in entropy is zero.

Since entropy is the only physical quantity we currently know about that seems to always result in a greater than or equal to zero result when the total "system" is considered, it seems to be a plausible explanation for the unidirectionality of "the arrow of time." The recent discovery of the Higg's Boson may offer other explanations for that...

I am beginning to see the difference. Thanks for the explanation.

"Spontaneous processes" ( http://en.wikipedia.org/wiki/Spontaneous_process ) would not be reversible because there is increased entropy involved.

A "reversible process" ( http://en.wikipedia.org/wiki/Reversi...hermodynamics) ) is a "quasistatic process" ( http://en.wikipedia.org/wiki/Quasistatic_processes ). Here is one quote from the reversible article:

Since it would take an infinite amount of time for the reversible process to finish, perfectly reversible processes are impossible.

Although I don't understand the "infinite amount of time" part, it looks like reversible processes generally don't exist.

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Originally Posted by YesNo

What would a spontaneous physical process with zero total entropy change be? Perhaps the earth's motion around the sun? I assume a reversible physical process would have to have zero total entropy change.

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Using the Gibbs Free Energy equation (deltaG=deltaH-TdeltaS) along with the requirement that a spontaneous process requires that deltaG be negative, we require that deltaH be negative, since TdeltaS is zero if deltaS is zero.

The earth's rotation around the sun is a spontaneous process, but it is not reversible. The motion of the earth-sun system is driven by gravity. The orbital motion of the earth around the sun has been going on for a very long time, and it might seem to some sort of perpetual motion machine, but it isn't. deltaS is a positive quantity for this process.