Understanding the Paradox of Backward Time Travel: Why We Can't Go Back

[Mentat]

Why we can't "go back".

I explained the paradox of backward time travel, in the old PFs, and I would like to do so again.

Here is why it is impossible to travel backwards in time (and it doesn't matter how far backwards):

As soon as you travel to a time that is before the exact time when you started traveling, you create paradox. If I start traveling at 5:00 A.M. (I know that using minutes, as a way of measuring exact time, is crude, but it should get the point across), and I travel back to 4:59, I have yet to start traveling. But, if I have yet to start traveling, how did I get to 4:59? The answer: I didn't, it's impossible. Unless someone can prove me wrong, it makes no sense to imply that I can start traveling, after having already arrived at my destination.

 

[Mentat]

Some people have suggested the "Pretzel Time" idea - which basically states that if (in the future) I travel back in time, then my future was already going to be in the past. I disagree with this idea.

I'm not going to get into a discussion of free will (that's for the Philosophy forum, and not really relevant to my argument).

However, there is the question of whether there are an infinite amount of "Mentats" in any given place. Because, if not, then there is no way that I am involved in some form of "loop time traveling", as the "Pretzel Time" idea will imply.

You see, if it is part of my future, to go back into the past, then it must be determined to be so. But I would thus, have to have been there, at that point in time. Then, in a universe where I was already there in 1987, I was about to be born the next year - and the "Mentat" that is born in 1988 will eventually travel back to my (the Mentat in 1987) time. We might, perhaps, meet each other, or maybe not, it's not really important; but both of us know that, soon, another one of us (the one that will be born next year) will pop up (of course, this is not true, the "third" Mentat would appear at exactly the same time as the other two - and so would the infinite "other" Mentats).

If this point needs clarification, just ask. I realize that it is a bit of a strange concept.

 

[Mentat]

People have also drawn up the "Different T dimensions" argument. This argument basically states that there are many (possibly infinite) different time dimensions; and that a person could travel back in time, but would be traveling, not to that point in time in his/her original T dimension, but in another (identical) one.

My side of this is that it is demonstrably true that every point on the T dimension, corresponds to every point on the 3 spatial dimensions that we know of. I would have to assume that this same reasoning applies to the rest of the spatial dimensions (but I can't know for sure). And, if this is true of all of the spatial dimensions, you cannot travel to a dimension that is "outside" of the one T dimension.

 

[Hurkyl]

You see, if it is part of my future, to go back into the past, then it must be determined to be so. But I would thus, have to have been there, at that point in time. Then, in a universe where I was already there in 1987, I was about to be born the next year - and the "Mentat" that is born in 1988 will eventually travel back to my (the Mentat in 1987) time. We might, perhaps, meet each other, or maybe not, it's not really important; but both of us know that, soon, another one of us (the one that will be born next year) will pop up (of course, this is not true, the "third" Mentat would appear at exactly the same time as the other two - and so would the infinite "other" Mentats).

You don't get an infinite number of Mentats looking from a non-Mentat perspective:...

In 1987, a fully grown Mentat appears in the universe.

In 1988, a baby Mentat was born.

In {future date}, the younger Mentat (which is the same age and has the same knowledge as the older Mentat did when he appeared) vanishes from the universe.


This "timeline" is perfectly consistent with you (instantly) traveling back in time, but yields no more than 2 Mentats at any instant.

Hurkyl

 

[Mentat]

Originally posted by Zefram
Say an electron interacts with some photons and flips around in time at 5:00; to observers like you and me it looks like two different (forward-in-time-travelling) particles, an electron and positron, annihilating in a flash of photons. However, that positron was really only the electron traveling backwards through time (after the flipping around in time). At 4:59 we therefore see the electron at two different stages of its life, one in which it's going forward and one in which it's going backwards. Can there be no positron because at 4:59 it hasn't started traveling backwards through time yet? Of course not, positrons are very real.

The analogy Feynman originally used to describe that whipping around in time for particles and their antiparticles was:



Since Feynman's interpretation of antimatter has been out there for over 50 years and apparently works well enough and is consistent, I would think it as least shows that traveling backwards through time isn't blatantly paradoxical.

First off, that means that it's still impossible for me to travel back in time; because, even if I had an anti-Mentat, he would travel back in time, not me.

I will continue this response later, I have to go now...

 

[Mentat]

Originally posted by Zefram
Say an electron interacts with some photons and flips around in time at 5:00; to observers like you and me it looks like two different (forward-in-time-travelling) particles, an electron and positron, annihilating in a flash of photons. However, that positron was really only the electron traveling backwards through time (after the flipping around in time). At 4:59 we therefore see the electron at two different stages of its life, one in which it's going forward and one in which it's going backwards. Can there be no positron because at 4:59 it hasn't started traveling backwards through time yet? Of course not, positrons are very real.

The analogy Feynman originally used to describe that whipping around in time for particles and their antiparticles was:



Since Feynman's interpretation of antimatter has been out there for over 50 years and apparently works well enough and is consistent, I would think it as least shows that traveling backwards through time isn't blatantly paradoxical.

Alright, to complete my response...

I would like to point out that Relativity states that an object's movement through time is inversely proportional to it's motion through space. Thus, the positron would have to be going much faster than the speed of light, and this isn't possible.

 

[Mentat]

Originally posted by Hurkyl
You don't get an infinite number of Mentats looking from a non-Mentat perspective:...

In 1987, a fully grown Mentat appears in the universe.

In 1988, a baby Mentat was born.

In {future date}, the younger Mentat (which is the same age and has the same knowledge as the older Mentat did when he appeared) vanishes from the universe.


This "timeline" is perfectly consistent with you (instantly) traveling back in time, but yields no more than 2 Mentats at any instant.

Hurkyl

Let's imagine that I was born in 1988, and then later traveled back to 1987 (because that was what I was predestined to do - my time was "looped"). Now the universe has two of me - as of 1988, that is - and the one that was born on 1988 (in a universe where there are two of that same person) travels backward...

Now, I'm not sure (anymore) but it seems as though this Mentat (the one that comes from a universe of two Mentats) should meet the other Mentat (that appeared in 1987), and so now the universe has three Mentats, and so on...

 

[Mentat]

Alright, I guess I withdraw the refutation of the Pretzel time idea. I was wrong.

However, Zefram, are you saying that Feynman ignores Special Relativity? That's a pretty good indication that he's wrong.

 

[climbhi]

Originally posted by Mentat
Zefram, are you saying that Feynman ignores Special Relativity? That's a pretty good indication that he's wrong.

Or that special relativity is wrong...

 

[Mentat]

Originally posted by climbhi
Or that special relativity is wrong...

You've got to be kidding.

 

[les]

Originally posted by Mentat
Let's imagine that I was born in 1988, and then later traveled back to 1987 (because that was what I was predestined to do - my time was "looped"). Now the universe has two of me - as of 1988, that is - and the one that was born on 1988 (in a universe where there are two of that same person) travels backward...

Now, I'm not sure (anymore) but it seems as though this Mentat (the one that comes from a universe of two Mentats) should meet the other Mentat (that appeared in 1987), and so now the universe has three Mentats, and so on...

I don't see how there would be a third Mentat and so on. It's possible for the time-travelling Mentat to meet the new-born Mentat in 1988. But that's it. Where does the third Mentat come from? The new-born Mentat will eventually grow-up and travel back in time to 1987. When he travels back in time one Mentat will exit from the loop while another one will be introduced in 1987. So it seems there are only 2 Mentats in the loop.

 

[les]

Originally posted by Mentat
As soon as you travel to a time that is before the exact time when you started traveling, you create paradox. If I start traveling at 5:00 A.M. (I know that using minutes, as a way of measuring exact time, is crude, but it should get the point across), and I travel back to 4:59, I have yet to start traveling. But, if I have yet to start traveling, how did I get to 4:59? The answer: I didn't, it's impossible. Unless someone can prove me wrong, it makes no sense to imply that I can start traveling, after having already arrived at my destination.

Not sure if I understand why it's a paradox. If you travel back to 4:59, wouldn't you meet the other you who is about to embark on a time-travel?

 

[Mentat]

Originally posted by les
Not sure if I understand why it's a paradox. If you travel back to 4:59, wouldn't you meet the other you who is about to embark on a time-travel?

How many of you are there, les? If, by traveling back ward in time, you can create as many of you as possible, what's the point of cloning ?

Seriously, if I go back in time, without chaning my position in space, I could not see the "other me" (even if such a thing could exist), because we would be occupying the same space.

 

[Alias]

Why do we assume that "the past" is a place that exists?

While I wish I had some math to support my hypothesis, I simply do not see any evidence that "the past" is a place that exists. And it follows, of course, that travel to a place that does not exists is impossible.

I firmly believe that time is an effect of expansion. Time is what appears to happen after one universe is replaced by the next. A single frame of a movie film has no "time". Time is only perceived when you look at successive frames of the film, one right after the other. It is not time that exists. It is the ability for our universe to allow for motion and/or action that is real. Time is an artifact of this process.

 

[DrChinese]

Originally posted by Mentat
Alright, I guess I withdraw the refutation of the Pretzel time idea. I was wrong.

However, Zefram, are you saying that Feynman ignores Special Relativity? That's a pretty good indication that he's wrong.

Feynman was a strong proponent of relativity, having been involved in the creation of relativistic quantum mechanics. I think this is what he got the Nobel for.

Anyway, he certainly demonstrated that our notion of time travel needs re-thinking. As I see it, time travel - at the quantum level - is not just possible, it is reality.

 

[Loren Booda]

Why restrict the arrow of causality to past-->future? As stated earlier, quantum processes are time symmetric, that is, they can proceed both ways. Some macroscopic entropic phenomena have localized anentropy (Prigogine), suggesting there an effect analogous to time reversal. Hawking claims that a "big crunch" following the big bang would maintain time direction, but if the universe is indeed isolated, given enough time quantum interactions will influence a repetition of its overall temporal history or overtake macroscopic physics as a whole.

The topology of spacetime, however, by its very nature may forbid the paradoxical interchange of past and future. Perhaps the present is a singularity that disallows relativity (except for "fuzzy" quantized spacetime) continuity of travel back in time along the time line.

 

[axeeonn]

It seems to me like time can go backwards, it just doesn't because time is more likely to go forwards than backwards.

Flow from order to disorder is identical to flow of time. Can time go backwards? Yes, it just doesn't happen because every proton, electron, and neutron in the universe would have to move back in time at the same exact moment. So the chances of that is about 1 : 10^90.

As for traveling back in time with some contraption, I just don't see that happening.

 

[wuliheron]

How do we know this very moment is not just another repetition, another temporal loop? Is it live, or is it memorex? Are we living out the lives we were destined to or are we destined to live free? In the final analysis, which each of us makes for ourselves, does it really matter? I don't think so. What matters is we take it in as it comes and make the most of the situation. For that, all you need is acceptance.

 

[CJames]

Reverse time travel indeed seems like a paradox to me. Situations such as the grandfather paradox seem to completely rule out any case in which the past is changed. However, even cases that don't change the past seem to completely and utterly violate the conservation of energy, considering that one second nothing is there, and suddenly you are there in the past.

 

[Mentat]

Originally posted by DrChinese
Feynman was a strong proponent of relativity, having been involved in the creation of relativistic quantum mechanics. I think this is what he got the Nobel for.

Anyway, he certainly demonstrated that our notion of time travel needs re-thinking. As I see it, time travel - at the quantum level - is not just possible, it is reality.

Perhaps you could give the reason why you think this is possible?

Also, if Feynman was such a strong supporter of Relativity, why did he suggest something that contradicted one of GR's principles?

 

[Mentat]

Originally posted by CJames
Reverse time travel indeed seems like a paradox to me. Situations such as the grandfather paradox seem to completely rule out any case in which the past is changed. However, even cases that don't change the past seem to completely and utterly violate the conservation of energy, considering that one second nothing is there, and suddenly you are there in the past.

I agree about it's being a defiance of the conservation of energy (since going backward in time would decrease entropy). Good point.

 

[Mentat]

Originally posted by Alias
Why do we assume that "the past" is a place that exists?

While I wish I had some math to support my hypothesis, I simply do not see any evidence that "the past" is a place that exists. And it follows, of course, that travel to a place that does not exists is impossible.

I firmly believe that time is an effect of expansion. Time is what appears to happen after one universe is replaced by the next. A single frame of a movie film has no "time". Time is only perceived when you look at successive frames of the film, one right after the other. It is not time that exists. It is the ability for our universe to allow for motion and/or action that is real. Time is an artifact of this process.

Very good point, alias. The past is not a place that exists (and is thus not a place), because something that "does exist" exists in the present (as "does exist" is a term in the present tense).

 

[ElectrikRipple]

Oh but it is my friend

Mentat first off i would like to say that i respect you for your thoughts, but i would have to completely disagree. i think that the theory of multiple universes will help me out very much here. Everytime you make a new decision or do something different, a new universe is created for every alternate choice you could have made. I don't kno if this is the true theory, but if it isn't than i have made some modifications. I think that once you have figured out how to stay in the same universe to travel along "your" stretch of time (or the universe in which you believe you exist in right now reading this) then you can easily travel backwards and fowards. I'm not sure this is possible, for i have created a theory for when people ask me the question "But why aren't there time traveling tourists?" Well, perhaps in an alternate universe (one in which time travel is possible) there are. So what they should really be asking is why are there not universe traveling tourists and my answer to that is simply i do not know. I don't quite believe the whole "pretzel time theory" but i believe that time is a straight line that can be manipulated. if time is relative than it can indeed be manipulated and molded. If it is a matter of how to do so, then i believe that going into the future would create a sort of pretzel. Its like if u pull on a fishing line hard enough it come back with twists in it. I believe that if you travel into the future enough times than u will actually create this "pretzel" effect. Once this happens i believe that u will have only a certain amount of time before the time "line" straightens back out and can no longer be traveled on. Once you have the pretzel effect, u should be able to "jump" from one coil of the line to the other side of the coil. This would indeed put stress on the coil and the more peole that are jumping from one particular coil, then the speed at which it straightens will be quickened dramatically. I think I've written a lot, so read this and ask any question u feel like. Late
P.J.
Oh and check out my thread that i started on time traveling.

 

[quantumcarl]

Originally posted by Mentat
The past is not a place that exists (and is thus not a place), because something that "does exist" exists in the present (as "does exist" is a term in the present tense).

By your reasoning, mentat, if the past exists... it exists in the present and we are "traveling" through it as we type. Therefore, "time travel" is happening now.

Lets remember the old axioms:

"Tommorrow never comes."

"Yesterday's tommorrow is tommorrow's yesterday" (or today).

"Today is tommorrow's yesterday" and so on and so forth.

Therefore, logically, we are at the crossroads of change and we exist in the past, present and future simultaniously or in a quantum manner, now.

We could define this as traveling in the past, present and future... but it is more like being in the unique position of being able to change all three, now.

If there is a mathmatical way to say this please feel free to quote me in that language.

 

[Mentat]

Originally posted by ElectrikRipple
Mentat first off i would like to say that i respect you for your thoughts, but i would have to completely disagree. i think that the theory of multiple universes will help me out very much here. Everytime you make a new decision or do something different, a new universe is created for every alternate choice you could have made. I don't kno if this is the true theory, but if it isn't than i have made some modifications. I think that once you have figured out how to stay in the same universe to travel along "your" stretch of time (or the universe in which you believe you exist in right now reading this) then you can easily travel backwards and fowards. I'm not sure this is possible, for i have created a theory for when people ask me the question "But why aren't there time traveling tourists?" Well, perhaps in an alternate universe (one in which time travel is possible) there are. So what they should really be asking is why are there not universe traveling tourists and my answer to that is simply i do not know. I don't quite believe the whole "pretzel time theory" but i believe that time is a straight line that can be manipulated. if time is relative than it can indeed be manipulated and molded. If it is a matter of how to do so, then i believe that going into the future would create a sort of pretzel. Its like if u pull on a fishing line hard enough it come back with twists in it. I believe that if you travel into the future enough times than u will actually create this "pretzel" effect. Once this happens i believe that u will have only a certain amount of time before the time "line" straightens back out and can no longer be traveled on. Once you have the pretzel effect, u should be able to "jump" from one coil of the line to the other side of the coil. This would indeed put stress on the coil and the more peole that are jumping from one particular coil, then the speed at which it straightens will be quickened dramatically. I think I've written a lot, so read this and ask any question u feel like. Late
P.J.
Oh and check out my thread that i started on time traveling.

I thank you for your participation, ElectrikRipple.

Actually, there is one problem with your idea. You see, while there are many alternate universes (according to Multiverse theories), I think that there is only one time dimension for all of them. I believe this because the "splitting apart" - that occurs whenever you make a decision (as you pointed out) - happens at a certain point in time, and it continues forward in time, even though they are entirely different space.

 

[Mentat]

Originally posted by quantumcarl
By your reasoning, mentat, if the past exists... it exists in the present and we are "traveling" through it as we type. Therefore, "time travel" is happening now.

Lets remember the old axioms:

"Tommorrow never comes."

"Yesterday's tommorrow is tommorrow's yesterday" (or today).

"Today is tommorrow's yesterday" and so on and so forth.

Therefore, logically, we are at the crossroads of change and we exist in the past, present and future simultaniously or in a quantum manner, now.

We could define this as traveling in the past, present and future... but it is more like being in the unique position of being able to change all three, now.

If there is a mathmatical way to say this please feel free to quote me in that language.

quantumcarl, no offense (seriously, don't take this the wrong way), but are you trying to confuse the issue with weird posts, or was there a genuine point that you were trying to make and that I failed horribly at noticing?

Re-read my post, I said that the past can't exist (IOW, "exist now") because "now" is the present.

 

[Alias]

Is there evidence that the past continues to exist somewhere, such that we might go there? I don't think so.

Paradox is not why travel to the past is impossible. It is not that traveling to the past would create insoluble equations. The answer to "why not" is that the past does not exist.

Of course, for the purist, this sucks because you can't use the same argument about the future. While the future does not exist either, it is possible to 'nearly freeze' yourself (by traveling at relativistic speeds)in your present state so that you might travel to a distant future. Unfortunately, there's no going back.

There may be something important to learn from this unreflexive argument. Somehow being good for the goose is not necessarily good for the gander.

 

[Royce]

Why can't we go back

exactly. Logically time travel implys a deterministic universe. Our language and minds cannot coupe with time travel so logically it is impossible but physically if we were made of antimatter or could convert ourseves to antimatter without encountering normal matter we would of course be traveling back in time. Then when we got to where we want to be we would simply convert ourselves back into "normal" matter; but, if we encountered ourselves traveling in normal time we would of cours annialate both of ourselves . Personally I would rather crawl through a worm hole and pull it in after me.

Remember, wherever you go in life, there you are. Candis Bergen

 

[Mentat]

Originally posted by Royce
exactly. Logically time travel implys a deterministic universe. Our language and minds cannot coupe with time travel so logically it is impossible but physically if we were made of antimatter or could convert ourseves to antimatter without encountering normal matter we would of course be traveling back in time. Then when we got to where we want to be we would simply convert ourselves back into "normal" matter; but, if we encountered ourselves traveling in normal time we would of cours annialate both of ourselves . Personally I would rather crawl through a worm hole and pull it in after me.

Remember, wherever you go in life, there you are. Candis Bergen

Hold on a second, Royce. You are saying that anti-matter paticles travel faster than the speed of light through space?

 

[Mentat]

"Arriving before leaving", a logical impossibility.

Perhaps this thread belongs in the Philosophy Forum, but it is an off-shoot of another thread (in this Forum) of mine, and so I just posted it here.

People have pointed out the idea that there are anti-particles that move backward in time. I don't think these people realize the consequences of such travel - viewing it as just like traveling backward through a spatial dimension. This is not so because traveling backwards through time = arriving before leaving. IOW, I would have to get to point B (my supposed destination), without ever having left point A (my supposed starting point) - without, in fact, every having been on point A (my supposed starting point). This makes no logical sense - unless someone would care to prove otherwise - and thus the idea of particles that travel backwards in time cannot be true.

I now ask that everyone post their comments (whether for or against my reasoning). Any contructive comment is appreciated.

As this isn't really a new subject and just a continuation of another thread, I'm merging this with the original thread.

 

[chosenone]

Tachyons are the particle i think your talking about.If tachyons traveled backwards in time then anywhere in the time line moving forward tachyons would tavel back to the beginning of the universe,so all tachyons from all time periods would stop moving backwards when they reach there,but that would also mean that at the big bang all tachyons in the entire existence of the universe would be there before the universe ever go here,thats kind of hard to believe!

 

[chosenone]

Since you like trying to debate time travel,and if is possible,try this one on for size.if you killed someone accidentally by something you did,what you could do is send a telepathic signal back in time telling your self what happen by giving your past self a preminition,of the up coming event that will cause the person death.why there seems to be no paradox in this one is because changing time has the problem about when it first happens then you go back to change it,what happens if it was suppose to be like that in the time line,what happened when you come up to the event the first time before it happened,when you changed it.this one has the ability to get around that,when you come up the the event the first time you had a precognitive experience where you saw your self accidentally killing someone,and you would just think its a warning to stop it before it happened and would believe that was meant to be not changing time,so when you send the signal back to do it,in the time line how would you know what happened first,if the first time you had a preminition,and that's that!

 

[Royce]

In the other thread I said that our language hense our logic is not built to handle time travel in either direction. We can go on forever trying to decide if we came back in time then our coming back in time is already in our past, present and future thus proving a deterministic universe without freewill. Going ahead in time implys the same thing for when the future does arrive we would already be there having in our past traveled to our future thus the future determins the past and the past determins our future. There is also the possibility that there is only one time, NOW and that the sequentail flow of time is an illusion caused by the limitation of our minds.
John Gribbins said that and electron traveling back in time was indistingquishable from a positron traveling forward in time, again Feynman diagrams. He also mentioned tachyons as going backwards in time and that time in Einstein's equations showed yup with a negative sign. Does that mean that we are actually traveling in negative time?
I was jokinly referring to those concepts. I just can't take any discussion of time travel seriously but it makes great SF which I've loved most of my life.

 

[Royce]

No, they travel backwards in time on a Feynman Diagram according to John Gribbin. A positron is indistinguishable from an electron moving backward in time. That is vertually a quote from the last book of his that I read on QM. In the same book, the name of which I can't remember right now, he mentioned the possibility of tachyons and said that they would have to move backward it time since any object approaching the speed of light has its time slowed down and a photon moving at the speed of light has 0 time or is outside of time anything such as a tachyon traveling faster that C must move backward in time or have negative time.

As you may have noticed I am brand new to this forum having just found it yesterday and I am enjoying it thoroughly. Thank you all.

 

[chosenone]

well tachyons are hypothesised to be hitting the planets surface as cosmic radiation,there traveling faster than light because,light is being slowed down as it is passing though the thick atmosphere,and the tachyons are'nt.but if they are traveling backwards intime,they would be hitting the surfaces before they entered the atmosphere.

 

[DrChinese]

Originally posted by Mentat
1. Perhaps you could give the reason why you think this is possible?

2. Also, if Feynman was such a strong supporter of Relativity, why did he suggest something that contradicted one of GR's principles?

1. Feynman Diagrams work in either time direction. There is nothing - at the quantum level - which inhibits photons from going from the future to the past. Indeed, I believe this is a part of the calculations for Feynman's path integrals - i.e. considering the effects of virtual anti-photons. Anyone?

2. Relativistic QM respects Special Relativity, not General Relativity.

As to GR itself: Probably everyone has speculated as to whether gravity flows from GR, or whether there is a quantum description which has GR as its approximation. And if that were the case, all kinds of strange things might be the case. So I'm not sure what you are getting at about Feynman.

 

[quantumcarl]

Originally posted by Mentat
was there a genuine point that you were trying to make and that I failed horribly at noticing?

Yes.

If you don't understand what I said... you may want to go back and re-read all those books in the elementary school library you've bragged about reading in grade 4.

My point is simple and well known throughout the western world.

Let me repeat. Just for you.

Today is tommorrow's yesterday and yesterday's tommorrow.

In this axiom we can see that the past, present and the future exist now.

Therefore we are in a unique, quantum position to travel through, experience and change all three conditions, simultaniously... past, present and future, now.

 

[ElectrikRipple]

so u think that all of the universes in which are created from decisions made are still traveling on the same time line and tehrefore there can only be one time line or whatever and that the same amount of time passes, no matter what universe/dimension/whatever u are in? this makes since if that's what ur saying if not then let me know before i reply to the theory itself
P.J. <<<<tired [zz)]

 

[ElectrikRipple]

Originally posted by Alias
Is there evidence that the past continues to exist somewhere, such that we might go there? I don't think so.

i like this idea
P.J. <<<<tired [zz)]

 

[ElectrikRipple]

Originally posted by quantumcarl
Yes.

If you don't understand what I said... you may want to go back and re-read all those books in the elementary school library you've bragged about reading in grade 4.

My point is simple and well known throughout the western world.

Let me repeat. Just for you.

Today is tommorrow's yesterday and yesterday's tommorrow.

In this axiom we can see that the past, present and the future exist now.

Therefore we are in a unique, quantum position to travel through, experience and change all three conditions, simultaniously... past, present and future, now.

carl...i don't care if u take offense to this bro but dude i don't know what's wrong with u and ur thinking process or u know what wow...

P.J. <<<<tired [zz)]

 

[kristofer]

Hi, guys.

I'm Kristofer's brother. He has an interest in learning about physics and science. When he told me this, I suggested this forum as a place to begin. He's lots of ideas about solving world problems, particularly in the area of alternative fuels and the like but he's only eleven and needs to learn the rudiments. Please be patient with him, as you have time. Many of you can answer his questions much better than I can.

I've encouraged Kris to post here. He is only just learning but he'd like to learn a lot, and this is about the best place for learning what he really wants.

Thanks, everyone. Have a great Sunday!

 

[mouseman]

Ar matey, welcome aboard! We hopes ye'll find our humble ship to yer likin's. Batten down, bucco's! We sail fer the Sea of Knowledge!

Man, I'm such a dufus.

 

[ElectrikRipple]

mouseman lol wut was that?
P.J.

 

[Royce]

Originally posted by Mentat
Hold on a second, Royce. You are saying that anti-matter paticles travel faster than the speed of light through space?

Mentat,
I posted a reply earlier then thought later about it. After reading other posts I guess that moving backward in time does mean moving faster that the speed of light also. I hadn't realized this implication before.
Then I read another post about tachyons moving backward and coming together at the Big Bang. Sure that would be a logical conclusion but where did they come from, The Big Crunch or Rip? Had to be, logically.
Then I had another thought. If space is curved and a closed curve at that wouldn't that mean also that time too is curved and a closed curve also implying that the Big Band is the same as the Big Crunch?
The Beginning is the same event as the End in an endless loop of time.
Of course everything would be wiped clean at the Crunch/Bang, no information could be passed on to the next cycle so it wouldn't really be a loop, would it?
I then remembered that one of the problems with the BIG BANG is that anti-matter should have been created at the same time and rated as "normal" matter. They would collide and annihilate each other nearly as fast as they were created but obviously this didn't happen because we are here in a "normal" matter universe. Could it be that matter travels slower than light in one direction in time and that anti-matter travels faster than light in the opposite direction in time thus they never meet except in the end/beginning. Are they separated by the light barrier and time direction? This would also imply the sum total of enery/matter = 0. It could be that all of this is nothing but a logal fluctuation of the vacuum.

What do you think? Is it possible or am I really as crazy as I and others think?

 

[Mentat]

Everyone, this is a very important point that nearly everyone has missed: For something to get from point A to point B (or point B to point A, it doesn't matter) implies eventuality, eventuality, in turn, necessitates that a certain amount of time expire. For a certain amount of time to expire (or pass) you have to get from the present to the future (or at least what used to be considered the future), not from the present to the past.[/color].

I think that this is the big hurdle that people just aren't getting past. People speak of anti-particles that travel backward in time. This is utter foolishness, because to travel from point A to point B implies eventuality. When I said that you cannot arrive before leaving, this (the statement in red) is what I was trying to express.

 

[Mentat]

The problems with "pretzel" time.

I will now show why I don't think that the "Pretzel time" works:

1) One dimension
Time is a dimension. It is not a set of dimensions. Because of this, it cannot curl backward. To curl necesitates an extra dimenion (a curled one).

2) Not the past, but the future:
Even if time were pretzeled, one would not be going to the past, but the future. You see, the point in time which corresponds to 5:30 pm, July 4th 1776 (for example) does not exist anymore (as Alias has been stressing) - it didn't exist at 5:31 of that date, and will in fact never exist again. So, when I travel "back" to this point, I am actually traveling to a new point - one in which I was there - and since it is new, it must have come into existence after the time I started traveling; and if it came into existence after I started traveling, then I am in the future, not the past.

 

[Alias]

Originally posted by Zefram
This is the point being challenged (at least by myself); the idea I'm arguing is that time has no intristic "flow" and that the distinction between "past" and "future" is a matter of perspective...

STOP! You are exactly correct up to that point. This idea that we all seem to have that says that 'time flows' in a particular direction, is an artifact of our perception. I believe that time does not flow, but that the universe renews. The universe does not 'endure' in time. Time is what you get with the repitition of renewing universes. Again the analogy is the frames of a movie film. You get no movie unless you look at the frames consecutively. No motion is apparent, no action occurs, unless you view the film dynamically. The same may be true with our universe. This hypothesis, if true, would also indicate quantized space and thus, non-continuous motion. These 'would be facts' conveniently explain the limiting speed of light and the fact that no mass can travel faster than this. I think that from this point of view, the Lorentz transformations can tell us much about the qualities of space.

 

[ElectrikRipple]

Originally posted by Mentat
I will now show why I don't think that the "Pretzel time" works:

1) One dimension
Time is a dimension. It is not a set of dimensions. Because of this, it cannot curl backward. To curl necesitates an extra dimenion (a curled one).

There's your problem. Why do u have to have two dimensions before u time can be "pretzeled"? A slinky isn't made up of multiple strips. Am i missing something?
P.J.

 

[ElectrikRipple]

Originally posted by Zefram
This is the point being challenged (at least by myself); the idea I'm arguing is that time has no intristic "flow"

People often view time as a river flowing towards the future. Which i guess make since. Time travels into the future. The present becomes future and the future becomes present. But can u not swim against the current of the river of time?
P.J.

 

[Royce]

Originally posted by Zefram
This is the point being challenged (at least by myself); the idea I'm arguing is that time has no intristic "flow" and that the distinction between "past" and "future" is a matter of perspective as in spatial coordinates (and that there need not be a preferred direction along the time axis that everything must move in--things can travel along the time axis in either direction).

Zefram,
I agree. Everything that I have read about relativity and QM including Hawking and Feynman says that time is just another dimension with no preferred direction. From what I ave read all of Newton's, Lorentz's, Maxwell's and Einstein's formula work equally well no matter whether time is + or -. In fact Einstein's formulas ended up with time as - which I mentioned before. Everyone seems to ignore that fact as insignificant, but is it. Nor is time constant nor linear and may well be quantumized (is that a word?) as well as space. Some seem to think that space may be at the Plank level as someone else mentioned in this forum. To me, in my humble opinion EVERTHING IS RELATIVE and QUANTUM.
Consider the photon. It moves only at the speed of light. It cannot stop or slow down or speed up. If it does then it is no longer a photon. It is it's own anti-particle. And at the speed of light it is outside of time. In its perspective it travels instantaneously from one point to another. Which means that it is everywhere along its path at the same time even though that path may be thousands of light years long.