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Author Topic: How does time relate to the photon?  (Read 32073 times)

Ethos

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How does time relate to the photon?
« on: 05/04/2009 18:57:01 »
I'm going to suggest a hypothetical circumstance which is quite impossible, nevertheless, it has raised a question in my mind which has many possible interpretations.

If one could hitch a ride on a photon, present theory suggests they would experience absolutely no passage of time. If I'm correct in this understanding, starting with the Big Bang, and progressing forward in time until the theorized heat death of the universe, how would the rider view the total experience? Would I be correct in saying; Because no time had elapsed for this passenger, the Big Bang and the Heat Death of the universe would be a single event with absolutely no time occuring in between. And with such a perspective, would the passenger have, from their position, already arrived at the Heat Death?

If this assumption is correct, then the future is already determined and it can't be changed...........................Ethos


 

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How does time relate to the photon?
« Reply #1 on: 05/04/2009 22:13:06 »
Its a question about 'time' and 'distance', is it not:)
If you were able to 'live' like a photon and not 'interact', then 'time' would not be and neither would any universe. Distance wouldn't exist either. From that point of view nothing would happen. As i see it a photon only 'experience' anything when it interact with 'spacetime', otherwise it may be 'enlightened' :) But it sure as he** won't be able to think. Thinking takes place in 'time' but the photon?

And that is a result of 'frames of reference', then again, what is the photons 'frame of reference' as it travels. We see it as belonging to our definitions of distance and time, and it does, from our frame of reference.
 

Ethos

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How does time relate to the photon?
« Reply #2 on: 05/04/2009 22:21:59 »
Its a question about 'time' and 'distance', is it not:)
Actually, the question is about determinism. Because the photon's experience, has the future and the past all rolled up into oneness. In essence, the photon has already completed it's journey into the future, therefore, the future is fixed and cannot be changed.
 

Offline Vern

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How does time relate to the photon?
« Reply #3 on: 05/04/2009 23:27:27 »
It doesn't equate to me that the photon, being timeless, implies, or somehow requires, a deterministic universe. We say the photon can't experience time because it moves at the speed of light. But maybe that is just a construct we use for thinking about time. It may not be a general rule we can use for global predictions.
 

lyner

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How does time relate to the photon?
« Reply #4 on: 06/04/2009 00:06:07 »
Its a question about 'time' and 'distance', is it not:)
Actually, the question is about determinism. Because the photon's experience, has the future and the past all rolled up into oneness. In essence, the photon has already completed it's journey into the future, therefore, the future is fixed and cannot be changed.
I don't think that necessarily follows. You can look at a page of random numbers (they can be truly random - not just a pseudo random sequence which a computer can produce). You (playing the part of the photon) can see all of the numbers at once. But if you read each number at a time (playing the part of you and me) there is nothing about the third number which determines the fourth number (and so on) so you are experiencing a sequence which is not predetermined. That is the equivalent of living our lives - in time - when a photon will 'experience' its life - without time.

« Last Edit: 06/04/2009 00:07:43 by sophiecentaur »
 

Ethos

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How does time relate to the photon?
« Reply #5 on: 06/04/2009 02:07:53 »
I don't think that necessarily follows. You can look at a page of random numbers (they can be truly random - not just a pseudo random sequence which a computer can produce).
The key word here is "random".

What determines the state of randomness?

I personally don't believe in randomness. I know there are those who will argue that quantum interactions are the best case scenario in support of the state of randomness. I believe however, that science has yet to uncover all the information necessary to unravel the cause and effect connection responsible for these phenomenon. The deeper we dig, and the more information we collect, I believe, will eventually find the causes and we will abandon this notion of randomness.........Ethos
 

Offline lightarrow

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How does time relate to the photon?
« Reply #6 on: 06/04/2009 18:01:14 »
I'm going to suggest a hypothetical circumstance which is quite impossible, nevertheless, it has raised a question in my mind which has many possible interpretations.

If one could hitch a ride on a photon, present theory suggests they would experience absolutely no passage of time. If I'm correct in this understanding, starting with the Big Bang, and progressing forward in time until the theorized heat death of the universe, how would the rider view the total experience? Would I be correct in saying; Because no time had elapsed for this passenger, the Big Bang and the Heat Death of the universe would be a single event with absolutely no time occuring in between. And with such a perspective, would the passenger have, from their position, already arrived at the Heat Death?

If this assumption is correct, then the future is already determined and it can't be changed...........................Ethos
Can we talk about very very fast moving starships, instead of photons? Moving so near c that you can't much say the difference? Ok, then, nothing changes in the sense that time still exist, space still exist. What changes is the values of distances (spatial or temporal) between events, as measured in 2 different frames of references. Example: how do you know that our visible universe is not already moving at ~ light speed with respect to a greater universe outside our visible one? Are we without time or without space? Consider a photon: it moves at c with respect to us, ok? So, aren't we all moving at c with respect it? But we are still experiencing space, time......
« Last Edit: 06/04/2009 18:03:06 by lightarrow »
 

Offline LeeE

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How does time relate to the photon?
« Reply #7 on: 06/04/2009 20:02:48 »
I don't think you need to complicate things by trying to use impossible analogies.

For any degree of time-dilation where the rate of time is > 0 events will occur in an order, one before the other, and so on, but where the rate of time drops to zero there is no scope for order, so all events would appear to be simultaneous.  However, with no time, the events couldn't really be regarded as events at all, because they would neither start or end.  Instead, anything that existed in different states, during the course of it's lifetime in it's own frame of reference, would have to be seen as existing in a single super-position of all it's states.

This would also seem to apply to the act of observation itself; if no time is to pass, the observation can neither be started or ended, so if it is to exist/happen at all it must be in the form of one of a super-position of actions, the observation being both endlessly performed and not performed.

If there's really any problem here, I think it's more because the question is contradictory; it asks about the concept of 'future' in a context where time has no meaning.  The answer then, is that the concept of 'future' is meaningless in a context where there is no time.
 

lyner

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How does time relate to the photon?
« Reply #8 on: 06/04/2009 20:55:35 »
Your last para. Spot on!
 

Ethos

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How does time relate to the photon?
« Reply #9 on: 06/04/2009 21:16:40 »

If there's really any problem here, I think it's more because the question is contradictory; it asks about the concept of 'future' in a context where time has no meaning.  The answer then, is that the concept of 'future' is meaningless in a context where there is no time.
Excellent point LeeE, and to eveyone who contributed to this thread, Vern, lightarrow, sophie, and yor_on, you have cleared this question up for me,............Thanks
« Last Edit: 06/04/2009 21:19:25 by Ethos »
 

Offline lightarrow

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How does time relate to the photon?
« Reply #10 on: 06/04/2009 21:26:16 »
For any degree of time-dilation where the rate of time is > 0 events will occur in an order, one before the other, and so on,
No. If two spatially separated events A and B occur in an order (A first and then B), they can occur in the reverse order (B first and then A) in another frame of reference moving with respect to the first.

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but where the rate of time drops to zero there is no scope for order, so all events would appear to be simultaneous. 
In my starship travelling at ~ c I experience time in the same way as before the travel.
 

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How does time relate to the photon?
« Reply #11 on: 07/04/2009 03:46:53 »
Lightarrow "Consider a photon: it moves at c with respect to us, ok? So, aren't we all moving at c with respect it? But we are still experiencing space, time...."

Lovely idea :)
Although a photon is a boson and your spaceship is made of fermions.
There seems to be a very strict division between those two states as I understands it, so when traveling we won't ever have that same 'no time' experience as the bosons (photons) does, would you agree to that? That's what makes photons so strange to me. They interact with us in time and space, but never sharing the 'equivalence' I sort of expect.
 

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How does time relate to the photon?
« Reply #12 on: 07/04/2009 21:58:33 »
For any degree of time-dilation where the rate of time is > 0 events will occur in an order, one before the other, and so on,
No. If two spatially separated events A and B occur in [a temporal] order (A first and then B), they can occur in the reverse [temporal] order (B first and then A) in another frame of reference moving with respect to the first.

My emphasis.

This is logically correct, but the other frame of reference must be one where the direction of movement along the temporal axis is in the opposite direction to ours when it seems that within our spacetime environment everything moves along the temporal axis in the same direction.  That is, unless it is stationary, of course.  This isn't to say that this alternate frame of reference is impossible, but for us to be able to experience it would seem to require movement along a single axis in opposite directions, simultaneously.  While there's no problem with moving along several different axis in different directions and at different rates, which is how we move through space, when we're referring to the same and single temporal axis, then we can move either one way or the other, but not both.

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Quote
but where the rate of time drops to zero there is no scope for order, so all events would appear to be simultaneous. 
In my starship travelling at ~ c I experience time in the same way as before the travel.

Yes, you would experience time normally, but if you could reach 'c' so that no time passes, you will just experience what happens in zero time i.e. nothing.
 

Offline yor_on

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How does time relate to the photon?
« Reply #13 on: 08/04/2009 01:49:35 »
Wasn't it Einstein who said that one of the most important things (or the most important?) he ever did find of value, when wondering of our universe, was imagination? I like that.
 

Ethos

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How does time relate to the photon?
« Reply #14 on: 08/04/2009 04:36:20 »

Yes, you would experience time normally, but if you could reach 'c' so that no time passes, you will just experience what happens in zero time i.e. nothing.
Now I'm really getting confused. Could you plese clear this up for me?
If we consider a photon created at the Big Bang traveling unobstructed thru space until the present, from it's frame of reference, no time has elapsed. And looking into the future, choosing one of these photons that is fortunate enough to make it to the theorized heat death of the universe, it should have also experienced no passage of time.

If this scenario is correct, then for this photon at least, the future was predetermined at it's creation. And if we can agree upon that premise, all photon futures must be therefore, predetermined.

This is the point I'm trying to examine within this thread. If, with the creation of light, it's future is also determined, then likewise, all of history is. For without light, we would have no means to observe the passage of this history. For the photon, the past and the future are inextricably connected. And we as observers are held captive by the information light gives us. And that information was determined at it's creation..........................Ethos
« Last Edit: 08/04/2009 05:11:02 by Ethos »
 

Offline lightarrow

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How does time relate to the photon?
« Reply #15 on: 08/04/2009 09:11:01 »
For any degree of time-dilation where the rate of time is > 0 events will occur in an order, one before the other, and so on,
No. If two spatially separated events A and B occur in [a temporal] order (A first and then B), they can occur in the reverse [temporal] order (B first and then A) in another frame of reference moving with respect to the first.

My emphasis.

This is logically correct, but the other frame of reference must be one where the direction of movement along the temporal axis is in the opposite direction to ours when it seems that within our spacetime environment everything moves along the temporal axis in the same direction. 

Maybe I haven't explained myself well. I'm not talking about going back in the time, but normally travelling in space. If you are in a starship A and you are observing your friend in another equal starship B approaching you from left and going to right faster than you, both starships going to right (so the starships' "heads" are on the right, and the "tails" on the left)  then in the frame of reference of your starship you see these events in this temporal order (HA = head of A; TB = tail of B, ecc):

1. HBTA --> TBTA --> HBHA

Instead, from his frame of reference:

2. HBTA --> HBHA --> TBTA.

As you see, the events coloured in blue and red are in reversal temporal order.
This is due to the fact that, for Lorentz contraction, you see your friend's starship shorter than your, and he sees the opposite.

Edit. I assumed it as obvious, but in case it's not: HBTA means "the head of starship B is next to the tail of starship  A", ecc.
« Last Edit: 08/04/2009 15:35:37 by lightarrow »
 

Offline Vern

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How does time relate to the photon?
« Reply #16 on: 08/04/2009 13:31:40 »
Quote from: Ethos
This is the point I'm trying to examine within this thread. If, with the creation of light, it's future is also determined, then likewise, all of history is. For without light, we would have no means to observe the passage of this history. For the photon, the past and the future are inextricably connected. And we as observers are held captive by the information light gives us. And that information was determined at it's creation..........................Ethos
I don't think it is a given that the information in a photon of light was determined at the instant of its creation. The question may be more in the way we think about it. A photon-entity would sense distance as we sense time. So, instead sensing the passage of time, as we do while occupying an inertial frame, the photon would sense the passage of inertial frames while occupying time.
 

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How does time relate to the photon?
« Reply #17 on: 08/04/2009 15:43:35 »
In my starship travelling at ~ c I experience time in the same way as before the travel.

Yes, you would experience time normally, but if you could reach 'c' so that no time passes, you will just experience what happens in zero time i.e. nothing.

But that is true only in the hypothesis that our universe had a finite time of existence, because a finite number (universe time of existence) multiplied zero (Lorentz factor) is zero (time elapsed for the photon); but if the universe has an infinite time of existence (and, sincerely, neither me, nor you can know it) then infinite multiplied zero is undetermined (which means that it could be zero, a finite number or an infinite number).
 

Ethos

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How does time relate to the photon?
« Reply #18 on: 08/04/2009 16:23:55 »
I don't think it is a given that the information in a photon of light was determined at the instant of its creation.
Let's examine this statement;

If we accept the notion that the photon experiences no passage of time while traveling at c, we must also accept the notion that the photon's state of being has not changed. The only value we have to recognize the passage of time is change. If then, the photon has not changed it's character in any fashion, it remains the same as when it was created.

Let's perform a thought experiment:

We all recognize the sun is approx. 8 minutes away in light time. If we follow the course of photon X from it's source, the sun, to a location on earth, it will take 8 minutes our time to travel the distance. However, for the photon, this travel time was achieved in less than an instant. The photon will be absorbed by a patch of earth approx. 134 miles to the west of the initial straight line location. Photon X will change it's state of being upon being absorbed by this location, which in the photon's frame of reference happened instantly. Now; let's try and manipulate the outcome of this process.

Starting at zero minutes, the photon leaves the sun and the earth is rotating at it's regular pace, and 4 minutes later we decide to stop it's rotation. Will photon X still hit the same spot 134 miles to the west or, will it hit a spot on earth 67 miles to the west instead. According to our logic, it should hit the spot 67 miles to the west which is in straight line location with it's trajectory. And ofcourse, we all should recognize that the latter would be the case. However, photon X must have had prior information because it's final impact will occur 67 miles short of the previous estimate. From it's frame of reference, it's final destination was determined before we stopped the earth's rotation.

First question: Was our choice to stop the rotation predetermined?

Second question: Do we really have a choice or is history already cast in stone and we only have the delusion of free will?

.......................Ethos

« Last Edit: 08/04/2009 16:35:49 by Ethos »
 

Offline Vern

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How does time relate to the photon?
« Reply #19 on: 08/04/2009 17:14:50 »
Quote from: Ethos
If we accept the notion that the photon experiences no passage of time while travelling at c, we must also accept the notion that the photon's state of being has not changed. The only value we have to recognize the passage of time is change. If then, the photon has not changed it's character in any fashion, it remains the same as when it was created.

I think this is the notion that is causing our confusion. We assign an identity to an abstract function, photon. Then we say that abstract function, since it travels at c can experience no passage of time. But the wave-function concept is just a tool for thinking about a photon. I feel no compunction that this way of thinking about a photon must apply more globally.

QM avoids determinism by reducing everything to probability functions. I'm not sure how your deterministic photon could fit into QM theory. :)
 

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How does time relate to the photon?
« Reply #20 on: 08/04/2009 22:09:38 »
If this scenario is correct, then for this photon at least, the future was predetermined at it's creation. And if we can agree upon that premise, all photon futures must be therefore, predetermined.

You've gone back to referring to a time based property i.e. 'future' in a context where the duration of time = 0.  Within it's frame of reference, the photon would appear to have no future because it has no time context (but remember, this is all based on the assumption that non-matter items i.e. photons, have the same properties as matter items i.e. er... matter, and personally, I'm not sure that this is a safe assumption to make, the two types of item being intrinsically different in just about every other respect we can think of.  For example, non-matter items always travel at 'c' but matter items can never do this.  Non-matter items have no rest mass, but matter items always do, and so on...).
 

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How does time relate to the photon?
« Reply #21 on: 08/04/2009 22:37:15 »
For any degree of time-dilation where the rate of time is > 0 events will occur in an order, one before the other, and so on,
No. If two spatially separated events A and B occur in [a temporal] order (A first and then B), they can occur in the reverse [temporal] order (B first and then A) in another frame of reference moving with respect to the first.

My emphasis.

This is logically correct, but the other frame of reference must be one where the direction of movement along the temporal axis is in the opposite direction to ours when it seems that within our spacetime environment everything moves along the temporal axis in the same direction. 

Maybe I haven't explained myself well. I'm not talking about going back in the time, but normally travelling in space. If you are in a starship A and you are observing your friend in another equal starship B approaching you from left and going to right faster than you, both starships going to right (so the starships' "heads" are on the right, and the "tails" on the left)  then in the frame of reference of your starship you see these events in this temporal order (HA = head of A; TB = tail of B, ecc):

1. HBTA --> TBTA --> HBHA

Instead, from his frame of reference:

2. HBTA --> HBHA --> TBTA.

As you see, the events coloured in blue and red are in reversal temporal order.
This is due to the fact that, for Lorentz contraction, you see your friend's starship shorter than your, and he sees the opposite.

Edit. I assumed it as obvious, but in case it's not: HBTA means "the head of starship B is next to the tail of starship  A", ecc.

Sorry lightarrow, I misunderstood what you meant.

That's a good illustration but I think that what you're really pointing out is that there isn't an absolute frame of reference.  While each observer may see things happening in a different order, they will always see it in that order and the order will remain consistent within that frame of reference.  Neither craft could see a different order from their respective frames of reference.
 

Offline LeeE

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How does time relate to the photon?
« Reply #22 on: 08/04/2009 22:53:17 »
In my starship travelling at ~ c I experience time in the same way as before the travel.

Yes, you would experience time normally, but if you could reach 'c' so that no time passes, you will just experience what happens in zero time i.e. nothing.

But that is true only in the hypothesis that our universe had a finite time of existence, because a finite number (universe time of existence) multiplied zero (Lorentz factor) is zero (time elapsed for the photon); but if the universe has an infinite time of existence (and, sincerely, neither me, nor you can know it) then infinite multiplied zero is undetermined (which means that it could be zero, a finite number or an infinite number).

If we accept the BB hypothesis, only a finite amount of time can have elapsed for the universe up to this point in time.  Whether the universe goes on to exist for an infinite amount of time or not is open to debate, but for any specific time in the future only a finite amount of time can have elapsed.

While trying to do maths with ∞ doesn't give meaningful answers anyway, I have to disagree that ∞ * 0 is indeterminable; it will still be 0.
 

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How does time relate to the photon?
« Reply #23 on: 09/04/2009 01:03:42 »
Lightarrow, Just want to give you an eulogy for your precise and patient explanations of your logics, it's a pleasure reading you.

As for the discussion going on here I think I'll just will read up on you, for now.
Though I'm sure I'll have one (opinion) soon enough :)
I seem to have a lot of them ::))
« Last Edit: 09/04/2009 01:05:23 by yor_on »
 

Offline lightarrow

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How does time relate to the photon?
« Reply #24 on: 09/04/2009 08:55:10 »

But that is true only in the hypothesis that our universe had a finite time of existence, because a finite number (universe time of existence) multiplied zero (Lorentz factor) is zero (time elapsed for the photon); but if the universe has an infinite time of existence (and, sincerely, neither me, nor you can know it) then infinite multiplied zero is undetermined (which means that it could be zero, a finite number or an infinite number).

If we accept the BB hypothesis, only a finite amount of time can have elapsed for the universe up to this point in time.  Whether the universe goes on to exist for an infinite amount of time or not is open to debate, but for any specific time in the future only a finite amount of time can have elapsed.
If you are in a starship travelling at c you have lived zero time from the BB up to know, but since you live in a different time, you keep going ahead, till the end of the universe, so don't know how your consideration applies here.

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While trying to do maths with ∞ doesn't give meaningful answers anyway, I have to disagree that ∞ * 0 is indeterminable; it will still be 0.
Did you study mathematics?
 

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