Hello,
I was wondering if someone could answer a question I have about the Photon?
I am not a physicist, but am interested in the subject, and I posed a question on several boards, but no one has given me a straight answer, or seems to be able to.
Einstein said that as an object moves toward the speed of light time slows down for that object, and if the object passes (theoretically), the speed of light, time would flow in reverse.
My question is, is this true with the Photon? That is, since the photon travels at the speed of light, does that mean that time is stopped for a Photon?
I can think of many implications that this would have, yet I never hear it mentioned. Why?
I thank you in advance for your answers.
Robert
Some questions make no sense. "What blue is Machiavellian?" is an example. Measuring a particles time is associated with the ability to build a clock and put that clock in the same state of motion as the particle in question, and this you cannot do with light. But seeing as light moves faster than any massive particle, and that clocks of a particle moving relative to us are slower than our own clocks, then it might follow that the time of light moves slower than that of any massive particle. And the only non-negative number left after all the positive numbers are removed is zero. So you might say that time for light is stopped, but it would be like saying "Electric blue is Machiavellian" -- useless for any practical purpose.
It's amazing, just amazing.
I have posed this question ...10 times, and no physicist has ever given me a straight answer.
What is it?
Hard?
Hard just to say yes, or no?
Either time is stopped for a photon, or it is not. End of discussion. What the hell is "blue Machiavellian" and why do I care? Why do you even bring it up?
What are you talking about "building clocks" for? did anyone ask you if we needed to build a clock?
"Some questions make no sense?" You think that YOU do?
Does the "clock" you're talking about reside in the same universe as the photon? Then it makes sense, smart guy!
You: "...then it It might follow that the time of light..."
It "might?" these are very strict laws, are they not? So...DOES IT, or DOESN'T IT?
I sometimes honestly think that you physicists don't know. You don't know what the hell you're talking about, and that's why every answer is dressed in equations and references to "Blue Machiavellian."
Someone give me a straight answer! YES, or NO, is time stopped for a photon??????????
I have posed this question ...10 times, and no physicist has ever given me a straight answer.
What is it?
Hard?
Hard just to say yes, or no?
Either time is stopped for a photon, or it is not. End of discussion. What the hell is "blue Machiavellian" and why do I care? Why do you even bring it up?
What are you talking about "building clocks" for? did anyone ask you if we needed to build a clock?
"Some questions make no sense?" You think that YOU do?
Does the "clock" you're talking about reside in the same universe as the photon? Then it makes sense, smart guy!
You: "...then it It might follow that the time of light..."
It "might?" these are very strict laws, are they not? So...DOES IT, or DOESN'T IT?
I sometimes honestly think that you physicists don't know. You don't know what the hell you're talking about, and that's why every answer is dressed in equations and references to "Blue Machiavellian."
Someone give me a straight answer! YES, or NO, is time stopped for a photon??????????
In hope that you really want a layman's answer, I'll try.
Photons must move at c, because that is the only velocity available to them.
c is the maximum velocity available in our universe.
Time passes, and photons aren't immune to it. At one point the photon's electric field is at a maximum while the magnetic component is at the minimum for that photon's energy, at the next infinitesimal moment, the amplitude of the two components has changed, but the point-source has still moved at c. The phase has changed, but the energy remains...
So, no. Time doesn't stop for quanta, photons or otherwise. It becomes very important for higher-energy force carriers.
Photons must move at c, because that is the only velocity available to them.
c is the maximum velocity available in our universe.
Time passes, and photons aren't immune to it. At one point the photon's electric field is at a maximum while the magnetic component is at the minimum for that photon's energy, at the next infinitesimal moment, the amplitude of the two components has changed, but the point-source has still moved at c. The phase has changed, but the energy remains...
So, no. Time doesn't stop for quanta, photons or otherwise. It becomes very important for higher-energy force carriers.
As far as I understand from the photon's point of view it travels from one point to another instantaneously.
And if you don't use "clocks" to measure time, what do you use?
And if you don't use "clocks" to measure time, what do you use?
A more meaningful question is do we grew younger when we move faster than light? The answer is no.
Joseph adela
Joseph adela
The formula for determining time dilation in special relativity is:
deltat' =deltat/sqrt(1-(v/c)^2)
where:
deltat = the time interval between two co-local events (i.e. happening at the same place) for an observer in some inertial frame (e.g. ticks on his clock) – this is known as the proper time,
delta' = is the time interval between those same events, as measured by another observer, inertially moving with velocity v with respect to the former observer, (this would be you hitching a ride on the photon with a clock of your own in hand)
v = is the relative velocity between the observer and the moving clock (attached to your photon in your example)
c =is the speed of light
OK, so if your taking a ride on top a photon and you look back at a place where two events occur one right after the other. Then to everybody who is standing around watching the events occur in the same inertial frame as the events take place in, then they see the two events occur with a difference in time between the outcome of the two events occurring as deltat. In other words the first event occurs and then to everybody standing around watching these events occur the next one seems to happen, say just 1 second later.
Now you are riding along on a photon with a clock in hand, according to your clock time is passing at the same rate it does as if you were looking at your clock siting still at home and not riding along on top of a photon. Now you look back and you see the first event occurring, in the other inertial reference frame, and you want to know when the next event is going to occur. Given your speed is c then according to the above time dilation formula, the next event occurs after an infinite amount of time has passed since the first event occurred. So to you riding along on the photon it appears that time all around you has come to a stop, if you look at everything else that is supposed to be occurring throughout the universe it appears as if everything has simply stopped moving to you.
In other words it seems that time has come to a standstill for everything around you that you look at (that is not within your inertial reference frame), but if you look down at your own clock that you have in hand it still keeps on ticking just as it would if you were in your living room siting on the couch holding onto your clock and you look at it from this position.
So in short, time for the photon keeps passing at a "normal" rate with respect to the inertial reference frame the photon lies in (which is just a way of saying if you were moving along with the photon side by side with it then both you and the photon would experience time passing you by at the rate we are all used to),
but from the photon's point of view on everything else, that doesn't lie within its inertial reference frame (that isn't moving right along with the photon as "one group" on a fast voyage) it seems that time has stopped for all other events the photon sees while it is moving.
So no, time doesn't stop for the photon, it continues to move from the photons point of view upon itself and anything traveling along with it, but for everything else viewed from the photons perspective time does seem to have stopped for everything the photon "sees" that is not within its inertial reference frame.
That's why I had used you riding along with the photon with a clock in hand; because if you look at it like that, then you are also moving at light speed as you hitch a ride on top of the photon. So let's say the inertial reference frame for the photon includes the photon, you and the watch around your wrist, but nothing else (maybe some clothes so you don't have to take a naked ride on top of the photon). If you look down at your watch it will seem to be ticking right along as it normally does, but as you look at every other clock or what would normally be a series of events that occur over time everywhere else, it appears to you that all the other clocks have come to a stop and the series of events that usually occur over some period of time seem to be "stuck" just in the middle of an event but not progressing any further.
You said this at one point:
"Einstein said that as an object moves toward the speed of light time slows down for that object, and if the object passes (theoretically), the speed of light, time would flow in reverse."
You are kind of misinterpreting what Einstein was saying. He didn't say that time for an object as it approaches light speed slows for that object, but rather time viewed by that object in other inertial reference frames seems to have slowed down, but time for the object itself, if it had a watch on it and could read its own passage of time would see time pass at the rate we are used to seeing time pass at. Everything that lies outside the inertial reference frame of the fast moving object seems to be moving more slowly, including time, to anything inside the fast moving inertial reference frame. Like wise to other inertial reference frames, the thing that is moving very quickly, when viewed from these other inertial reference frames, seems to these other reference frames that time for the thing that is moving very quickly is also passing by very quickly for that thing. That's why for instance two people, one who is an astronaut and the other is not, who happen to be twins and hence are of the same age after enough time moving along at pretty fast speeds in space for the astronaut causes him to "become" perhaps microseconds older than his twin; because he has "jumped" into the future.
As he is moving in orbit around the Earth his velocity is great enough to cause a time dilation to a very small extent for him compared to people here on Earth. So when we look up at the watch on his wrist it appears to us to be moving a little more quickly than our clocks here on Earth. Likewise when he looks down at our clocks he sees them as moving a little more slowly than his watch. If you take the case to the extreme by replacing the astronaut with a photon that is wearing a watch moving at light speed. When the photon looks down at all the clocks on Earth it seems to the photon that all the clocks have come to a stop. When we look up at the watch the photon is wearing it seems to us that time is passing by for the photon at an infinite rate; but when the photon looks at its own watch it seems to be moving normally, just like when we look at our clocks on Earth they seem to be moving normally, but if we each look at the others clock/watch then things seem really different.
Like I said it seems to the photon that time is moving at a normal rate for it, but that everything around it that is not moving with the same velocity as the photon and is therefore within a different inertial reference frame, it seems to the photon that everything outside its inertial reference frame has stopped completely, including time. From the perspective of the photon it does seem kind of strange, when it looks at its own watch time seems to be moving normally, but when it looks at everything that is not within its inertial reference frame it seems that all life, events and time for everything else has come to a stop.
So to make a long story short, as far as a photon is concerned, time seems to move at a normal rate for the photon, but everything around the photon not within its inertial reference frame seems to have come to a stop, including time.
Many Smiles,
Craig
P.S. I wouldn't jump all over rpenner for his reply to your post. Nothing he said was incorrect, and when talking about special relativity, it is very common to speak of events as "ticks" on a clock. In fact if you look up time dilation on say Wikipedia, all they use is clocks for examples in describing time dilation. If your going to talk about time dilation on an object, even a photon, then you do need a clock to travel along with the photon along with another clock in a different inertial reference frame, in order to really speak about time moving more slowly or quickly for one object (clock) within its own inertial reference frame compared to time measured (another clock) in another inertial reference frame. If you want a mathematical description you can just use the Lorentz factor and calculate time differences, but if you want a description of the event, it is described almost always as two clocks, one in one inertial reference frame and the other in a different inertial reference frame moving with some velocity with respect to the first. He is also correct that no matter can ever obtain the speed of light and therefore a photon compared to any piece of mass that may obtain relativistic speeds, but not reach light speed, might seem to the fast moving piece of mass that everything around it seems to have slowed in time, but compared to the photon that can move even faster, that time all around it has actually stopped. In other words he is saying that indeed the fastest moving object looks around and sees time moving more slowly for everything around it than those things that can't move as quickly. Since a photon moves faster than any piece of mass can, then it may seem to the photon that the rate of time for everything else is far slower than if the photon were replaced with a tiny piece of mass that can not reach light speed and therefore the rate of time seen every where else by the tiny piece of mass isn't as slow as it is for the photon. He's correct.
It can even be taken a step further by saying that indeed from a photons point of view everything around it seems to have stopped, including time, but that's what the photon "sees" as it passes things by. When it looks down at its own watch it sees time moving at a normal rate. So it depends on what you mean when you say does time stop for a photon. Certainly from the perspective of the photon, everything surrounding it seems to have stopped, including time, but if you were traveling right along with the photon and looked at your own watch it would seem that time is passing by at a normal rate for both you and the photon. So it depends on which "clock" the photon looks at. If it looks at a clock here on Earth, then it would seem to the photon that all time has come to a stop, if it looks at a clock that is traveling right along next to it then it appears to the photon that time is moving at a normal rate; even though the rate of time in all other/different inertial reference frames, seems to have stopped when viewed from the photon's perspective.
I hope that helps.
deltat' =deltat/sqrt(1-(v/c)^2)
where:
deltat = the time interval between two co-local events (i.e. happening at the same place) for an observer in some inertial frame (e.g. ticks on his clock) – this is known as the proper time,
delta' = is the time interval between those same events, as measured by another observer, inertially moving with velocity v with respect to the former observer, (this would be you hitching a ride on the photon with a clock of your own in hand)
v = is the relative velocity between the observer and the moving clock (attached to your photon in your example)
c =is the speed of light
OK, so if your taking a ride on top a photon and you look back at a place where two events occur one right after the other. Then to everybody who is standing around watching the events occur in the same inertial frame as the events take place in, then they see the two events occur with a difference in time between the outcome of the two events occurring as deltat. In other words the first event occurs and then to everybody standing around watching these events occur the next one seems to happen, say just 1 second later.
Now you are riding along on a photon with a clock in hand, according to your clock time is passing at the same rate it does as if you were looking at your clock siting still at home and not riding along on top of a photon. Now you look back and you see the first event occurring, in the other inertial reference frame, and you want to know when the next event is going to occur. Given your speed is c then according to the above time dilation formula, the next event occurs after an infinite amount of time has passed since the first event occurred. So to you riding along on the photon it appears that time all around you has come to a stop, if you look at everything else that is supposed to be occurring throughout the universe it appears as if everything has simply stopped moving to you.
In other words it seems that time has come to a standstill for everything around you that you look at (that is not within your inertial reference frame), but if you look down at your own clock that you have in hand it still keeps on ticking just as it would if you were in your living room siting on the couch holding onto your clock and you look at it from this position.
So in short, time for the photon keeps passing at a "normal" rate with respect to the inertial reference frame the photon lies in (which is just a way of saying if you were moving along with the photon side by side with it then both you and the photon would experience time passing you by at the rate we are all used to),
but from the photon's point of view on everything else, that doesn't lie within its inertial reference frame (that isn't moving right along with the photon as "one group" on a fast voyage) it seems that time has stopped for all other events the photon sees while it is moving.
So no, time doesn't stop for the photon, it continues to move from the photons point of view upon itself and anything traveling along with it, but for everything else viewed from the photons perspective time does seem to have stopped for everything the photon "sees" that is not within its inertial reference frame.
That's why I had used you riding along with the photon with a clock in hand; because if you look at it like that, then you are also moving at light speed as you hitch a ride on top of the photon. So let's say the inertial reference frame for the photon includes the photon, you and the watch around your wrist, but nothing else (maybe some clothes so you don't have to take a naked ride on top of the photon). If you look down at your watch it will seem to be ticking right along as it normally does, but as you look at every other clock or what would normally be a series of events that occur over time everywhere else, it appears to you that all the other clocks have come to a stop and the series of events that usually occur over some period of time seem to be "stuck" just in the middle of an event but not progressing any further.
You said this at one point:
"Einstein said that as an object moves toward the speed of light time slows down for that object, and if the object passes (theoretically), the speed of light, time would flow in reverse."
You are kind of misinterpreting what Einstein was saying. He didn't say that time for an object as it approaches light speed slows for that object, but rather time viewed by that object in other inertial reference frames seems to have slowed down, but time for the object itself, if it had a watch on it and could read its own passage of time would see time pass at the rate we are used to seeing time pass at. Everything that lies outside the inertial reference frame of the fast moving object seems to be moving more slowly, including time, to anything inside the fast moving inertial reference frame. Like wise to other inertial reference frames, the thing that is moving very quickly, when viewed from these other inertial reference frames, seems to these other reference frames that time for the thing that is moving very quickly is also passing by very quickly for that thing. That's why for instance two people, one who is an astronaut and the other is not, who happen to be twins and hence are of the same age after enough time moving along at pretty fast speeds in space for the astronaut causes him to "become" perhaps microseconds older than his twin; because he has "jumped" into the future.
As he is moving in orbit around the Earth his velocity is great enough to cause a time dilation to a very small extent for him compared to people here on Earth. So when we look up at the watch on his wrist it appears to us to be moving a little more quickly than our clocks here on Earth. Likewise when he looks down at our clocks he sees them as moving a little more slowly than his watch. If you take the case to the extreme by replacing the astronaut with a photon that is wearing a watch moving at light speed. When the photon looks down at all the clocks on Earth it seems to the photon that all the clocks have come to a stop. When we look up at the watch the photon is wearing it seems to us that time is passing by for the photon at an infinite rate; but when the photon looks at its own watch it seems to be moving normally, just like when we look at our clocks on Earth they seem to be moving normally, but if we each look at the others clock/watch then things seem really different.
Like I said it seems to the photon that time is moving at a normal rate for it, but that everything around it that is not moving with the same velocity as the photon and is therefore within a different inertial reference frame, it seems to the photon that everything outside its inertial reference frame has stopped completely, including time. From the perspective of the photon it does seem kind of strange, when it looks at its own watch time seems to be moving normally, but when it looks at everything that is not within its inertial reference frame it seems that all life, events and time for everything else has come to a stop.
So to make a long story short, as far as a photon is concerned, time seems to move at a normal rate for the photon, but everything around the photon not within its inertial reference frame seems to have come to a stop, including time.
Many Smiles,
Craig
P.S. I wouldn't jump all over rpenner for his reply to your post. Nothing he said was incorrect, and when talking about special relativity, it is very common to speak of events as "ticks" on a clock. In fact if you look up time dilation on say Wikipedia, all they use is clocks for examples in describing time dilation. If your going to talk about time dilation on an object, even a photon, then you do need a clock to travel along with the photon along with another clock in a different inertial reference frame, in order to really speak about time moving more slowly or quickly for one object (clock) within its own inertial reference frame compared to time measured (another clock) in another inertial reference frame. If you want a mathematical description you can just use the Lorentz factor and calculate time differences, but if you want a description of the event, it is described almost always as two clocks, one in one inertial reference frame and the other in a different inertial reference frame moving with some velocity with respect to the first. He is also correct that no matter can ever obtain the speed of light and therefore a photon compared to any piece of mass that may obtain relativistic speeds, but not reach light speed, might seem to the fast moving piece of mass that everything around it seems to have slowed in time, but compared to the photon that can move even faster, that time all around it has actually stopped. In other words he is saying that indeed the fastest moving object looks around and sees time moving more slowly for everything around it than those things that can't move as quickly. Since a photon moves faster than any piece of mass can, then it may seem to the photon that the rate of time for everything else is far slower than if the photon were replaced with a tiny piece of mass that can not reach light speed and therefore the rate of time seen every where else by the tiny piece of mass isn't as slow as it is for the photon. He's correct.
It can even be taken a step further by saying that indeed from a photons point of view everything around it seems to have stopped, including time, but that's what the photon "sees" as it passes things by. When it looks down at its own watch it sees time moving at a normal rate. So it depends on what you mean when you say does time stop for a photon. Certainly from the perspective of the photon, everything surrounding it seems to have stopped, including time, but if you were traveling right along with the photon and looked at your own watch it would seem that time is passing by at a normal rate for both you and the photon. So it depends on which "clock" the photon looks at. If it looks at a clock here on Earth, then it would seem to the photon that all time has come to a stop, if it looks at a clock that is traveling right along next to it then it appears to the photon that time is moving at a normal rate; even though the rate of time in all other/different inertial reference frames, seems to have stopped when viewed from the photon's perspective.
I hope that helps.
Matter...particles themselves are clocks...correct?
Yes, sorry to seem frustrated. I do not mean to seem angry, it is just that I have been asking this question for some time, and no one seems to be able to give me a straight answer. I appreciate the help, I do, and I think I understand now.
Robert
Robert
QUOTE (Starwatcher314+Jan 3 2010, 01:07 AM)
Matter...particles themselves are clocks...correct?
Mauve Freudian.
Mauve Freudian.
QUOTE (Starwatcher314+Jan 2 2010, 06:12 PM)
Hello,
...since the photon travels at the speed of light, does that mean that time is stopped for a Photon?...
I thank you in advance for your answers.
Robert
The photon could be illustrated as a massless particle with a PRIMARY forward momentum (as an arrow in a forward direction) traveling at close the speed of light.
This is undoubtedly a fantastic vision in its own right.
But one would have to here add the postulated notion of the simultaneous state:
The photon could be illustrated as a massless particle with a SECONDARY spin momentum (as a spinning top in a circuitous direction) ALSO traveling at close the speed of light. This spin state would most likely come with its own complex dynamics:
There are other particle spin states besides the photon--the photon's spin direction crosses the forward momentum path, counters it (dwell), crosses the forward momentum path again, then accelerates in the direction of forward momentum (tach).
Keep in mind this spin momentum too, would be at near light speed.
Your question of timing becomes clearly complex, in light of these multi-momentum dynamics.
A particle that can be in TWO locations at once, AND, share the SAME location with other particles (without collision)...
..."transformed" or "converted" might be better explanatory words than "stopped".
...since the photon travels at the speed of light, does that mean that time is stopped for a Photon?...
I thank you in advance for your answers.
Robert
The photon could be illustrated as a massless particle with a PRIMARY forward momentum (as an arrow in a forward direction) traveling at close the speed of light.
This is undoubtedly a fantastic vision in its own right.
But one would have to here add the postulated notion of the simultaneous state:
The photon could be illustrated as a massless particle with a SECONDARY spin momentum (as a spinning top in a circuitous direction) ALSO traveling at close the speed of light. This spin state would most likely come with its own complex dynamics:
There are other particle spin states besides the photon--the photon's spin direction crosses the forward momentum path, counters it (dwell), crosses the forward momentum path again, then accelerates in the direction of forward momentum (tach).
Keep in mind this spin momentum too, would be at near light speed.
Your question of timing becomes clearly complex, in light of these multi-momentum dynamics.
A particle that can be in TWO locations at once, AND, share the SAME location with other particles (without collision)...
..."transformed" or "converted" might be better explanatory words than "stopped".
QUOTE (Starwatcher314+Jan 2 2010, 09:25 PM)
It's amazing, just amazing.
I have posed this question ...10 times, and no physicist has ever given me a straight answer.
What is it?
Hard?
Hard just to say yes, or no?
Either time is stopped for a photon, or it is not. End of discussion. What the hell is "blue Machiavellian" and why do I care? Why do you even bring it up?
What are you talking about "building clocks" for? did anyone ask you if we needed to build a clock?
"Some questions make no sense?" You think that YOU do?
Does the "clock" you're talking about reside in the same universe as the photon? Then it makes sense, smart guy!
You: "...then it It might follow that the time of light..."
It "might?" these are very strict laws, are they not? So...DOES IT, or DOESN'T IT?
I sometimes honestly think that you physicists don't know. You don't know what the hell you're talking about, and that's why every answer is dressed in equations and references to "Blue Machiavellian."
Someone give me a straight answer! YES, or NO, is time stopped for a photon??????????
I can understand your frustration in trying to get a straight answer to this question. The following extract from "Schrodinger's Kittens" by John Gribbin may be of interest:
"The Lorentz transformations tell us that time stands still for an object moving at the speed of light. From the point of view of the photon, of course, it is everything else that is rushing past at the speed of light. And under extreme conditions, the Lorentz-Fitzgerald contraction reduces the distance between all objects to zero. You can either say that time does not exist for the electromagnetic wave, so that it is everywhere along its path ( everywhere in the Universe ) at once; or you can say that distance does not exist for an electromagnetic wave, so that it "touches" everything in the Universe at once.
This is an enormously important idea, which I have never seen given due attention. From the point of view of the photon, it takes no time at all to cross the 150 million km from the Sun to the Earth ( or to cross the entire Universe), for the simple reason that this space interval does not exist for the photon. Physicists seem to ignore this remarkable state of affairs, because they know that no material object can ever be accelerated to the speed of light, so no human ( or mechanical ) observer is ever going to experience this strange phenomenon"
I think this last point is the one that rpenner was making.
By the way, there are a few bad fokkers around here but rp is not one of them !
I have posed this question ...10 times, and no physicist has ever given me a straight answer.
What is it?
Hard?
Hard just to say yes, or no?
Either time is stopped for a photon, or it is not. End of discussion. What the hell is "blue Machiavellian" and why do I care? Why do you even bring it up?
What are you talking about "building clocks" for? did anyone ask you if we needed to build a clock?
"Some questions make no sense?" You think that YOU do?
Does the "clock" you're talking about reside in the same universe as the photon? Then it makes sense, smart guy!
You: "...then it It might follow that the time of light..."
It "might?" these are very strict laws, are they not? So...DOES IT, or DOESN'T IT?
I sometimes honestly think that you physicists don't know. You don't know what the hell you're talking about, and that's why every answer is dressed in equations and references to "Blue Machiavellian."
Someone give me a straight answer! YES, or NO, is time stopped for a photon??????????
I can understand your frustration in trying to get a straight answer to this question. The following extract from "Schrodinger's Kittens" by John Gribbin may be of interest:
"The Lorentz transformations tell us that time stands still for an object moving at the speed of light. From the point of view of the photon, of course, it is everything else that is rushing past at the speed of light. And under extreme conditions, the Lorentz-Fitzgerald contraction reduces the distance between all objects to zero. You can either say that time does not exist for the electromagnetic wave, so that it is everywhere along its path ( everywhere in the Universe ) at once; or you can say that distance does not exist for an electromagnetic wave, so that it "touches" everything in the Universe at once.
This is an enormously important idea, which I have never seen given due attention. From the point of view of the photon, it takes no time at all to cross the 150 million km from the Sun to the Earth ( or to cross the entire Universe), for the simple reason that this space interval does not exist for the photon. Physicists seem to ignore this remarkable state of affairs, because they know that no material object can ever be accelerated to the speed of light, so no human ( or mechanical ) observer is ever going to experience this strange phenomenon"
I think this last point is the one that rpenner was making.
By the way, there are a few bad fokkers around here but rp is not one of them !
QUOTE (Starwatcher314+Jan 2 2010, 06:12 PM)
Hello,
I was wondering if someone could answer a question I have about the Photon?
I am not a physicist, but am interested in the subject, and I posed a question on several boards, but no one has given me a straight answer, or seems to be able to.
Einstein said that as an object moves toward the speed of light time slows down for that object, and if the object passes (theoretically), the speed of light, time would flow in reverse.
My question is, is this true with the Photon? That is, since the photon travels at the speed of light, does that mean that time is stopped for a Photon?
I can think of many implications that this would have, yet I never hear it mentioned. Why?
I thank you in advance for your answers.
Robert
First, Granouille, it was my understanding that light only moves at C in a perfect vacuum, and moves slower through other media. I thought this was the reason that prisms create rainbows and objects appear bent when submerged in water. Is this incorrect?
Second, my understanding of time being relative to photons basically goes like this: Imagine photons traveling at uniform velocity outward from an object. One plane of such photons would contain the pattern of the image of the object they are reflecting off of and that plane/image would travel through space at the speed of light (in whatever medium).
So time does seem to be frozen for the photons because only by viewing successive planes of photons do you get the appearance of movement, i.e. time.
Of course, if you imagine that each photon has its own clock, then I think you could say that time progresses for photons the same as any other particle, but it seems to me that it would make more sense to describe photon-time as distance, since photons don't stop or change direction outside of the curvature of space-time itself.
I always get confused thinking about light and time, but I'll put something into the discussion and see if it helps at all.
I was wondering if someone could answer a question I have about the Photon?
I am not a physicist, but am interested in the subject, and I posed a question on several boards, but no one has given me a straight answer, or seems to be able to.
Einstein said that as an object moves toward the speed of light time slows down for that object, and if the object passes (theoretically), the speed of light, time would flow in reverse.
My question is, is this true with the Photon? That is, since the photon travels at the speed of light, does that mean that time is stopped for a Photon?
I can think of many implications that this would have, yet I never hear it mentioned. Why?
I thank you in advance for your answers.
Robert
First, Granouille, it was my understanding that light only moves at C in a perfect vacuum, and moves slower through other media. I thought this was the reason that prisms create rainbows and objects appear bent when submerged in water. Is this incorrect?
Second, my understanding of time being relative to photons basically goes like this: Imagine photons traveling at uniform velocity outward from an object. One plane of such photons would contain the pattern of the image of the object they are reflecting off of and that plane/image would travel through space at the speed of light (in whatever medium).
So time does seem to be frozen for the photons because only by viewing successive planes of photons do you get the appearance of movement, i.e. time.
Of course, if you imagine that each photon has its own clock, then I think you could say that time progresses for photons the same as any other particle, but it seems to me that it would make more sense to describe photon-time as distance, since photons don't stop or change direction outside of the curvature of space-time itself.
I always get confused thinking about light and time, but I'll put something into the discussion and see if it helps at all.
Calm down, Starwatcher! There IS NO layman's explanation for some questions, especially for those generated by uninformed speculation, like yours. By the way, Penner was just using an ANALOGY to help you understand why your question can never be answered the way you would like.
If you must know, the actual answer is "no." But don't ask us why, because you need to do a lot more studying before you will be able to appreciate an explanation.
Thanks to everyone who pitched-in here! I found your contributions interesting and enjoyable to read.
If you must know, the actual answer is "no." But don't ask us why, because you need to do a lot more studying before you will be able to appreciate an explanation.
Thanks to everyone who pitched-in here! I found your contributions interesting and enjoyable to read.
QUOTE
First, Granouille, it was my understanding that light only moves at C in a perfect vacuum, and moves slower through other media. I thought this was the reason that prisms create rainbows and objects appear bent when submerged in water. Is this incorrect?
It is correct.
For your further enjoyment, google "Cerenkov radiation".
QUOTE (Edward 3+Jan 3 2010, 03:54 PM)
"This is an enormously important idea, which I have never seen given due attention. From the point of view of the photon, it takes no time at all to cross the 150 million km from the Sun to the Earth ( or to cross the entire Universe)"
This is what I was waiting to hear...that light can traverse, or is in touch with the entire Universe at once.
And again, it isn't that simple.
An electron could be anywhere, literally. But most often it isn't.
An electron could be anywhere, literally. But most often it isn't.
QUOTE (Starwatcher314+Jan 3 2010, 06:10 PM)
This is what I was waiting to hear...that light can traverse, or is in touch with the entire Universe at once.
Then you must of heard this nonsense from some complete friggin idiot (via braindead eddie, no less)- much of the material universe (and increasing, due to current cosmic expansion) is both invisible to us and unreachable with regards to light-speed transit .... a mammoth part of the beast, whose separation velocity relative to us, far exceeds c.
Then you must of heard this nonsense from some complete friggin idiot (via braindead eddie, no less)- much of the material universe (and increasing, due to current cosmic expansion) is both invisible to us and unreachable with regards to light-speed transit .... a mammoth part of the beast, whose separation velocity relative to us, far exceeds c.
QUOTE (Bivalves+Jan 3 2010, 06:45 PM)
Then you must of heard this nonsense from some complete friggin idiot (via braindead eddie, no less)- much of the material universe (and increasing, due to current cosmic expansion) is both invisible to us and unreachable with regards to light-speed transit .... a mammoth part of the beast, whose separation velocity relative to us, far exceeds c.
Can you not read - on top of all your other problems Geoffrey. I didn't say it , I was quoting verbatim from a book and I clearly stated my source. Now why don't you be a good little lad and either respond to the question posed in the OP or else pi$$ off - preferably the latter
Can you not read - on top of all your other problems Geoffrey. I didn't say it , I was quoting verbatim from a book and I clearly stated my source. Now why don't you be a good little lad and either respond to the question posed in the OP or else pi$$ off - preferably the latter
Please feel free to do the same. Except you might constrain yourself to just the latter.
QUOTE (Granouille+Jan 3 2010, 07:11 PM)
Please feel free to do the same. Except you might constrain yourself to just the latter.
Thanks for the neg - how do you know he's not Geoffrey, not that it matters. More important is that he does not understand this bit of my post:
"Lorentz-Fitzgerald contraction reduces the distance between all objects to zero".
Do you? Considering that this was your contribution so far one would have to entertain some doubts
"An electron could be anywhere, literally. But most often it isn't."
Thanks for the neg - how do you know he's not Geoffrey, not that it matters. More important is that he does not understand this bit of my post:
"Lorentz-Fitzgerald contraction reduces the distance between all objects to zero".
Do you? Considering that this was your contribution so far one would have to entertain some doubts
"An electron could be anywhere, literally. But most often it isn't."
You are completely incorrect in your statement. Except for thanking me for the neg, of course.
QUOTE (Granouille+Jan 3 2010, 08:14 PM)
You are completely incorrect in your statement. Except for thanking me for the neg, of course.
What a significant contributon - I suspect you are fully aware that this statement has a unique distinction - it has absolutely no content. That's not easy - well done
What a significant contributon - I suspect you are fully aware that this statement has a unique distinction - it has absolutely no content. That's not easy - well done
A compliment from the master. I blush: I couldn't hope to outdo you in your forte!
QUOTE (Edward 3/Starwatcher+)
This is an enormously important idea, which I have never seen given due attention..
Speak to your own attention needs. Read more on the following subjects: "Quantum Entanglement", "Spooky Action at a Distance", "Time Dilation" for some basic understanding of the dynamics here.
Now the last I heard was that if someone could travel at c then time will have stopped for them. Yet seeing the above equation if v = c then you end up with deltat' = deltat/0. That to me doesn't say that time is stopped. That to me says that deltat' is either undefined or doesn't exist.
Now the last I heard was that if someone could travel at c then time will have stopped for them. Yet seeing the above equation if v = c then you end up with deltat' = deltat/0. That to me doesn't say that time is stopped. That to me says that deltat' is either undefined or doesn't exist.
Hi there,
I believe that the deltat' is the change in time seen from an inertial reference frame moving with zero velocity, with respect to some moving reference frame with velocity v (I say zero velocity because if it is moving, but just not as fast, then the difference between the two speeds of the two different frames can be considered to be the speed of the first frame with respect to a non moving second frame, so the speed of the first frame is relative to the stationary one).
Having said that, if you were traveling in space quite fast with a velocity v and you looked back at a clock here on Earth, the successive ticks on the clock would appear to happen more quickly than the ticks on the clock on the wall inside your space vehicle. So with respect to Earth you are moving more slowly through time then people here on Earth and hence is the reason you can "travel into the future" if moving fast enough; because while you only may have seen 24 hours pass by aboard you ship, the time here on Earth that may have passed by could be 30 hours, so when you come home you traveled 6 hours "into the future".
You are not actually traveling into the future it is simply that the rate of time aboard your spaceship is "slower" than that on Earth, or time is moving more quickly on Earth with respect to time flow inside your ship. So when you get back to Earth it seems to everyone around you that you have been able to travel into the future as according to your clock you were only gone for say 24 hours while on Earth it appeared that you were gone for, say, 24 days.
So when viewed from your fast moving craft, the time on Earth appears to be moving at a faster rate than time aboard your ship. The faster you move the faster the ticks on the clock on Earth move as seen aboard your ship. Now if you take the limit of v approaching c what you find is that it appears that time on Earth compared to the flow of time aboard your ship has is moving at almost an infinite rate.
Your speed is so great that the successive ticks of a clock aboard your ship when viewed from Earth seem to take longer and longer between ticks. Again in the limit of v approaching c the next tick of the clock aboard your ship when viewed from Earth essentially never occurs; if you were actually capable of reaching the speed of c the infinite answer you get from the formula:
deltat' = deltat/sqrt(1 - (v/c)^2)
implies that the next tick of the clock aboard your ship when viewed from Earth is not just very, very far away from occurring, but will never occur. There will be no next tick for a clock aboard your ship when viewed from Earth as a change in time no longer exists on your ship when viewed from Earth.
So your ship's clock when viewed from Earth if you were somehow able to obtain the speed of light with your ship, would appear to have simply stopped moving all together. Therefore with respect to any outside observer time for you inside your ship has come to a halt. The only way to mathematically convey that there will never be another tick seen occurring on the clock inside your ship when viewed from Earth is to say the time between ticks on your clock aboard your ship
when viewed from Earth is infinite. That is there is no place on the time line in the future that, when viewed from Earth, the next tick of your clock will occur.
Saying there is an infinite amount of time between ticks on the clock aboard your ship when viewed from Earth is simply stating that the flow of time aboard your ship when viewed from Earth has come to a stop. The next tick of your clock occurs (again and like always when viewed from Earth) not just a very, very long time from now, but it occurs at a time that is infinitely far away from the current time. Since infinity does not exist on a number line, but rather is a concept, then it conveys that the next tick must never occur no matter how long you wait to see it change, it won't because the time between ticks on your clock when viewed from Earth have been spread infinitely far apart; which is the same as saying there will be no next tick on the clock aboard your ship ever when viewed from Earth.
I know I keep using Earth as the reference frame to compare the flow of time on your ship to, I'm doing so because it is convenient and I think it is easier to understand these concepts using Earth as a "stationary" inertial reference frame and a space ship moving with some velocity v with respect to Earth as the moving reference frame.
So yes, the mathematical formula will yield an infinite value if your ship is capable of reaching a speed of c, so it no longer gives you the time that needs to pass before another tick on your clock when viewed from Earth will occur; but rather by yielding an infinite result it is telling you that there will never be a time change aboard your ship when viewed from Earth; or put another way the amount of time that needs to pass in order for someone here on Earth to see your clock advance by one tick is infinitely long - restated - it will never occur because it is not just very, very far away on the time line, but it doesn't even exist on the time line, so there can never be any change in time aboard your ship when viewed from Earth.
Of course there is a problem even when just "thinking" about traveling at speed c. If time aboard your ship when viewed from outside your ship from Earth, Mars, Venus, wherever seems to have come to a stop aboard your ship when viewed from any of these places, the opposite is also true. That is time on Earth when viewed from your ship seems to be moving, again not just very,very quickly, but rather it seems to be passing at an infinite rate. So if you were able to obtain light speed with your ship, while all time aboard your ship when viewed from Earth appears to be stopped, to you all time viewed on Earth from your ship seems to pass by in an instant. So you get to see all future events at the same instant of time; and if time does come to an end someday then you'll be there to see it end. If time goes on forever, as is currently assumed, then you will see all future events happen all at once; talk about sensory overload, whew! Never mind the fact that if you could reach light speed your mass would become infinite in amount which would require an infinite amount of energy to keep you moving at speed c. I don't think there's an infinite amount of energy or mass within our universe, so basically one can never obtain the speed of light unless one becomes a photon.
Another effect of being able to obtain the speed of c is that because time and space are interwoven concepts; that is they coexist together. When you look out and see time passing at an infinite rate, space is also infinitely condensed into a point; so you are everywhere at the same time watching time pass by at an infinite rate. These are of course things that can't ever happen to us, but they are a direct result of the mathematics when your speed v is replaced with speed c. Of course even if you could reach the speed of c with your ship, the clocks aboard your ship when viewed by you (also aboard the ship) are moving at the normal rate we are used to seeing time move at, even though when viewed from Earth it seems that time has come to a stop for you and your ship, aboard it time seems to be moving normally; that's why it's called relativity. The time seen passing for something moving at a different speed than you are appears to be moving either more quickly or more slowly relative to your reference frame; and like wise the flow of your time seen from the other differently speeding object is also different than the flow of time with respect to that same object.
So, for you, no matter how fast you are moving, time seems to flow at a constant rate when you look at your watch. If you look at other objects whose speeds are different than yours, the rate at which time passes for these other objects when viewed by you is different than the flow of time you see when you look down at your watch. So the flow of time for things that are moving with a different speed with respect to you, when viewed by you, is relative to the difference in the speed of these other things and your speed.
I hope that helps. I do understand what you are getting at in that the function yields infinity for a speed of c for v and not an actual number. It just means that there is no defined length of time that exists such that the clock moving at speed c will change in time, i.e. tick even once. Which is the same as saying if there is an infinite value for an amount of time that is needed before the clock that is moving at speed c when viewed to tick even once, then it will simply never tick again as long as it is moving at speed c because the next tick is infinitely far away, or put another way simply doesn't exist; therefore if the next moment in time can never be reached aboard your ship because it doesn't exist when viewed from something moving slower than c, than time must be stopped aboard your ship when viewed from something not moving at speed c; even though you on your ship when you look at your clock it seems to be moving normally it appears to have stopped to everything viewing it that is not moving at the same speed you are.
Many Smiles,
Craig
Speak to your own attention needs. Read more on the following subjects: "Quantum Entanglement", "Spooky Action at a Distance", "Time Dilation" for some basic understanding of the dynamics here.
QUOTE (Starwatcher+)
....that light can traverse, or is in touch with the entire Universe at once.
Only for those photons leaving THE SAME LIGHT SOURCE at THE SAME TIME INTERVAL.
Important snippets from this photon forum:
--time for light is stopped, but it would be like saying "Electric blue is Machiavellian" -- useless for any practical purpose.
--Cerenkov radiation and the relation of lightspeed to water.
--the inertial reference frame .
--light has multi-momentum dynamics.
Only for those photons leaving THE SAME LIGHT SOURCE at THE SAME TIME INTERVAL.
Important snippets from this photon forum:
--time for light is stopped, but it would be like saying "Electric blue is Machiavellian" -- useless for any practical purpose.
--Cerenkov radiation and the relation of lightspeed to water.
--the inertial reference frame .
--light has multi-momentum dynamics.
"Speak to your own attention needs. Read more on the following subjects: "Quantum Entanglement", "Spooky Action at a Distance", "Time Dilation" for some basic understanding of the dynamics here."
Not an expression of my opinion - I was quoting somebody else - have a look back the thread.
Not an expression of my opinion - I was quoting somebody else - have a look back the thread.
QUOTE (Edward 3+Jan 4 2010, 06:16 PM)
Not an expression of my opinion - I was quoting somebody else
The statement got a lot of mileage. Too much.
Correction noted.
The statement got a lot of mileage. Too much.
Correction noted.
QUOTE (keith*+Jan 5 2010, 04:04 AM)
The statement got a lot of mileage. Too much.
Correction noted.
I do not understand your reference to a "correction". There was nothing to correct. I take it you meant you were withdrawing your earlier incorrect attribution of the statement to me !! Apology accepted
Correction noted.
I do not understand your reference to a "correction". There was nothing to correct. I take it you meant you were withdrawing your earlier incorrect attribution of the statement to me !! Apology accepted
QUOTE (Starwatcher314+Jan 3 2010, 06:10 PM)
"This is an enormously important idea, which I have never seen given due attention. From the point of view of the photon, it takes no time at all to cross the 150 million km from the Sun to the Earth ( or to cross the entire Universe)"
This is what I was waiting to hear...that light can traverse, or is in touch with the entire Universe at once.
But not from the point of view of the Universe.
Or ever from your point of view.
It's called relativity for a reason.
This is what I was waiting to hear...that light can traverse, or is in touch with the entire Universe at once.
But not from the point of view of the Universe.
Or ever from your point of view.
It's called relativity for a reason.
QUOTE
deltat' =deltat/sqrt(1-(v/c)^2)
Now the last I heard was that if someone could travel at c then time will have stopped for them. Yet seeing the above equation if v = c then you end up with deltat' = deltat/0. That to me doesn't say that time is stopped. That to me says that deltat' is either undefined or doesn't exist.
QUOTE (H2O+Jan 11 2010, 02:30 AM)
Now the last I heard was that if someone could travel at c then time will have stopped for them. Yet seeing the above equation if v = c then you end up with deltat' = deltat/0. That to me doesn't say that time is stopped. That to me says that deltat' is either undefined or doesn't exist.
Hi there,
I believe that the deltat' is the change in time seen from an inertial reference frame moving with zero velocity, with respect to some moving reference frame with velocity v (I say zero velocity because if it is moving, but just not as fast, then the difference between the two speeds of the two different frames can be considered to be the speed of the first frame with respect to a non moving second frame, so the speed of the first frame is relative to the stationary one).
Having said that, if you were traveling in space quite fast with a velocity v and you looked back at a clock here on Earth, the successive ticks on the clock would appear to happen more quickly than the ticks on the clock on the wall inside your space vehicle. So with respect to Earth you are moving more slowly through time then people here on Earth and hence is the reason you can "travel into the future" if moving fast enough; because while you only may have seen 24 hours pass by aboard you ship, the time here on Earth that may have passed by could be 30 hours, so when you come home you traveled 6 hours "into the future".
You are not actually traveling into the future it is simply that the rate of time aboard your spaceship is "slower" than that on Earth, or time is moving more quickly on Earth with respect to time flow inside your ship. So when you get back to Earth it seems to everyone around you that you have been able to travel into the future as according to your clock you were only gone for say 24 hours while on Earth it appeared that you were gone for, say, 24 days.
So when viewed from your fast moving craft, the time on Earth appears to be moving at a faster rate than time aboard your ship. The faster you move the faster the ticks on the clock on Earth move as seen aboard your ship. Now if you take the limit of v approaching c what you find is that it appears that time on Earth compared to the flow of time aboard your ship has is moving at almost an infinite rate.
Your speed is so great that the successive ticks of a clock aboard your ship when viewed from Earth seem to take longer and longer between ticks. Again in the limit of v approaching c the next tick of the clock aboard your ship when viewed from Earth essentially never occurs; if you were actually capable of reaching the speed of c the infinite answer you get from the formula:
deltat' = deltat/sqrt(1 - (v/c)^2)
implies that the next tick of the clock aboard your ship when viewed from Earth is not just very, very far away from occurring, but will never occur. There will be no next tick for a clock aboard your ship when viewed from Earth as a change in time no longer exists on your ship when viewed from Earth.
So your ship's clock when viewed from Earth if you were somehow able to obtain the speed of light with your ship, would appear to have simply stopped moving all together. Therefore with respect to any outside observer time for you inside your ship has come to a halt. The only way to mathematically convey that there will never be another tick seen occurring on the clock inside your ship when viewed from Earth is to say the time between ticks on your clock aboard your ship
when viewed from Earth is infinite. That is there is no place on the time line in the future that, when viewed from Earth, the next tick of your clock will occur.
Saying there is an infinite amount of time between ticks on the clock aboard your ship when viewed from Earth is simply stating that the flow of time aboard your ship when viewed from Earth has come to a stop. The next tick of your clock occurs (again and like always when viewed from Earth) not just a very, very long time from now, but it occurs at a time that is infinitely far away from the current time. Since infinity does not exist on a number line, but rather is a concept, then it conveys that the next tick must never occur no matter how long you wait to see it change, it won't because the time between ticks on your clock when viewed from Earth have been spread infinitely far apart; which is the same as saying there will be no next tick on the clock aboard your ship ever when viewed from Earth.
I know I keep using Earth as the reference frame to compare the flow of time on your ship to, I'm doing so because it is convenient and I think it is easier to understand these concepts using Earth as a "stationary" inertial reference frame and a space ship moving with some velocity v with respect to Earth as the moving reference frame.
So yes, the mathematical formula will yield an infinite value if your ship is capable of reaching a speed of c, so it no longer gives you the time that needs to pass before another tick on your clock when viewed from Earth will occur; but rather by yielding an infinite result it is telling you that there will never be a time change aboard your ship when viewed from Earth; or put another way the amount of time that needs to pass in order for someone here on Earth to see your clock advance by one tick is infinitely long - restated - it will never occur because it is not just very, very far away on the time line, but it doesn't even exist on the time line, so there can never be any change in time aboard your ship when viewed from Earth.
Of course there is a problem even when just "thinking" about traveling at speed c. If time aboard your ship when viewed from outside your ship from Earth, Mars, Venus, wherever seems to have come to a stop aboard your ship when viewed from any of these places, the opposite is also true. That is time on Earth when viewed from your ship seems to be moving, again not just very,very quickly, but rather it seems to be passing at an infinite rate. So if you were able to obtain light speed with your ship, while all time aboard your ship when viewed from Earth appears to be stopped, to you all time viewed on Earth from your ship seems to pass by in an instant. So you get to see all future events at the same instant of time; and if time does come to an end someday then you'll be there to see it end. If time goes on forever, as is currently assumed, then you will see all future events happen all at once; talk about sensory overload, whew! Never mind the fact that if you could reach light speed your mass would become infinite in amount which would require an infinite amount of energy to keep you moving at speed c. I don't think there's an infinite amount of energy or mass within our universe, so basically one can never obtain the speed of light unless one becomes a photon.
Another effect of being able to obtain the speed of c is that because time and space are interwoven concepts; that is they coexist together. When you look out and see time passing at an infinite rate, space is also infinitely condensed into a point; so you are everywhere at the same time watching time pass by at an infinite rate. These are of course things that can't ever happen to us, but they are a direct result of the mathematics when your speed v is replaced with speed c. Of course even if you could reach the speed of c with your ship, the clocks aboard your ship when viewed by you (also aboard the ship) are moving at the normal rate we are used to seeing time move at, even though when viewed from Earth it seems that time has come to a stop for you and your ship, aboard it time seems to be moving normally; that's why it's called relativity. The time seen passing for something moving at a different speed than you are appears to be moving either more quickly or more slowly relative to your reference frame; and like wise the flow of your time seen from the other differently speeding object is also different than the flow of time with respect to that same object.
So, for you, no matter how fast you are moving, time seems to flow at a constant rate when you look at your watch. If you look at other objects whose speeds are different than yours, the rate at which time passes for these other objects when viewed by you is different than the flow of time you see when you look down at your watch. So the flow of time for things that are moving with a different speed with respect to you, when viewed by you, is relative to the difference in the speed of these other things and your speed.
I hope that helps. I do understand what you are getting at in that the function yields infinity for a speed of c for v and not an actual number. It just means that there is no defined length of time that exists such that the clock moving at speed c will change in time, i.e. tick even once. Which is the same as saying if there is an infinite value for an amount of time that is needed before the clock that is moving at speed c when viewed to tick even once, then it will simply never tick again as long as it is moving at speed c because the next tick is infinitely far away, or put another way simply doesn't exist; therefore if the next moment in time can never be reached aboard your ship because it doesn't exist when viewed from something moving slower than c, than time must be stopped aboard your ship when viewed from something not moving at speed c; even though you on your ship when you look at your clock it seems to be moving normally it appears to have stopped to everything viewing it that is not moving at the same speed you are.
Many Smiles,
Craig
OP:
First of all, relativity technically only applies to accelerating massive objects, and doesn't apply to photons in the same sense as it does to particles.
Light simply moves through space-time along the shortest possible path.
Technically, if V=C, you do not get "reverse time" nor do you get "outside time". you get division by zero, showing that the formula does not hold true for all Velocities.
Even if V were somehow greater than C, you still would not have "negative time". You would have "imaginary time" or "complex time", which in spite of the fake-sounding name, "imaginary numbers" are very much real and have real world applications in optics and electronics...(whether or not imaginary time is real.)
So, contrary to Science Fiction, a "Tachyon" does not technically move backwards through time at all. If they exist at all, they would move "sideways" through time, in the positive direction along the imaginary axis.
I don't know of any equations that would produce a negative vectored tachyon, so the process may be completely irreversible, or it just may be that the "tachyon" result is nonsense based on input which the equations were never intended to handle (which is by far the most likely possibility).
First of all, relativity technically only applies to accelerating massive objects, and doesn't apply to photons in the same sense as it does to particles.
Light simply moves through space-time along the shortest possible path.
Technically, if V=C, you do not get "reverse time" nor do you get "outside time". you get division by zero, showing that the formula does not hold true for all Velocities.
Even if V were somehow greater than C, you still would not have "negative time". You would have "imaginary time" or "complex time", which in spite of the fake-sounding name, "imaginary numbers" are very much real and have real world applications in optics and electronics...(whether or not imaginary time is real.)
So, contrary to Science Fiction, a "Tachyon" does not technically move backwards through time at all. If they exist at all, they would move "sideways" through time, in the positive direction along the imaginary axis.
I don't know of any equations that would produce a negative vectored tachyon, so the process may be completely irreversible, or it just may be that the "tachyon" result is nonsense based on input which the equations were never intended to handle (which is by far the most likely possibility).
If A is at rest and B is moving, A sees the clocks on B moving slowly, but B thinks his clocks are running at the usual speed and that A's clocks were slow. So A would say that time has stopped for the photon , but the photon (if it had a brain or clocks) would think that its clocks were moving at the correct rate.
"since the photon travels at the speed of light, does that mean that time is stopped for a Photon?"
-YES
When a photon is emitted at a source and later absorbed at a destination, the transition is instantaneous for the photon.
So when a photon from the Andromeda galaxy reaches a detector on earth, one should not think of the photon actually travelling through space, but one should think of an instantaneous quantum transition.
-YES
When a photon is emitted at a source and later absorbed at a destination, the transition is instantaneous for the photon.
So when a photon from the Andromeda galaxy reaches a detector on earth, one should not think of the photon actually travelling through space, but one should think of an instantaneous quantum transition.
QUOTE (alphachapmtl+Mar 27 2010, 05:26 PM)
"since the photon travels at the speed of light, does that mean that time is stopped for a Photon?"
Matter, from my crank reasoning; is an affect of multidimensional trans-geometry residing on the wavefront surface of it's parental trans-geometry (universe hypersurface) - A photon however, unlike matter, is trans-geometry residing on a wavefront surface aspect of an electron's wavestate - not bound, as such, to our hypersurface, merely in transit beyond - Therefore, has both 'velocity' and 'time', albeit of differing dimensional sensibility - this sucker travels through hyperspace .... and hyperspace, for us, is everywhere.
Yours truly - Foghorn + 2 bottles of stunningly delicious Austrailian wine, and the remnants of a gin bottle from yesterday.
............ hic!
Matter, from my crank reasoning; is an affect of multidimensional trans-geometry residing on the wavefront surface of it's parental trans-geometry (universe hypersurface) - A photon however, unlike matter, is trans-geometry residing on a wavefront surface aspect of an electron's wavestate - not bound, as such, to our hypersurface, merely in transit beyond - Therefore, has both 'velocity' and 'time', albeit of differing dimensional sensibility - this sucker travels through hyperspace .... and hyperspace, for us, is everywhere.
Yours truly - Foghorn + 2 bottles of stunningly delicious Austrailian wine, and the remnants of a gin bottle from yesterday.
............ hic!
Imbibulation in hyperspace results in effects, not affects.
Ah say...
Ah say...
QUOTE (Kaeru+Mar 27 2010, 09:51 PM)
Imbibulation in hyperspace results in effects, not affects.
Ah say...
Cheers, although I somewhat prefer occular ingestion.
Ah say...
Cheers, although I somewhat prefer occular ingestion.
Is it possible to hitch a ride on a Photon? And thus travel at the speed of light.
QUOTE (odellmar+Apr 22 2012, 11:05 PM)
Is it possible to hitch a ride on a Photon? And thus travel at the speed of light.
First of all you have to make yourself mass less.
First of all you have to make yourself mass less.
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