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Canada Bob
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I know that a photon traveling from the Sun takes around 8 minutes to get to Earth, but, how long does the photon "think" {if it had a stopwatch} it took to get from the Sun to Earth ?
Chronos said:A particle traveling at c does not experience time irrespective of distance traveled.
Canada Bob said:OK, forget the photon, suppose a bloke in a "spaceship" {a bloke who owns an atomic stopwatch, or the like} zipped across 93 Million miles, how long would he think he'd traveled ?
'different' isn't the correct term, the correct term is 'does not apply'.Canada Bob said:Appreciated, that the photons time will be different,
Yes. See posts 2 and 3.Canada Bob said:shouldn't it be calculable ?
If you mean time elapsed on a spaceship traveling at some fraction of c with respect to the Earth rest frame, use Lorentz transformations to get the length contraction of the Sun-Earth distance in the rest frame of the ship:Canada Bob said:Appreciated, that the photons time will be different, but, "much" is a moveable feast, shouldn't it be calculable ?
Canada Bob said:Appreciated, that the photons time will be different, but, "much" is a moveable feast, shouldn't it be calculable ?
Canada Bob said:if I divide the distance by the speed of light I get around 8 minutes but that's from my point of view / my time scale, I'm not moving at the speed of light but the photon is, so the photon's time to cross that distance will be considerably much less than the 8 minutes that I perceive.
Canada Bob said:Hello Zapper, I guess the "problem" is, we aren't all on the same rung of the ladder, or even on the same ladder {of interest}. I'm a retired marine engineer with a curiosity about certain elements of the cosmos. I had hoped that my question, presented in layman's terms, might have solicited an opportunity for someone to enlighten me in similar terminology rather than present some egotist the opportunity to show how vastly superior they are to folks.
When folks have approached me requesting my expertise I have never looked on them with disgust, disregard or disrespect, just because they don't know what I know.
I don't have an appetite or a need to do that, or a frail enough ego to seek to put people down.
Thanks again Nugatory for your time and consideration, it's valued and appreciated.Nugatory said:If, as the sun passes the observer in the ship, he sends a flash of that light in the direction of the Earth that flash of light will reach the Earth before the Earth reaches the observer. The observer in the ship will find that the distance traveled by the light (which is considerably less than 93 million miles because of length contraction) divided by the time it takes for the light to reach the Earth (which is considerably less than eight minutes) is equal to the speed of light (of course).
Someone on Earth will interpret the same sequence of events as a flash of light being emitted from the ship as it passes the sun 93 million miles away; it takes the flash of light traveling at c eight minutes to cover the 93 million miles distance and reach the earth.
One interpretation uses clocks and distance measurements from a frame in which the Earth and sun are at rest, and the other uses clocks and distance measurements from a frame in which the ship is at rest. Neither interpretation tells us anything about "the photon's time" - that concept isn't even meaningful because we'd need a clock from a frame in which the photon is at rest to give us the photon's time, and there is no such frame because the thing is moving at the speed of light in all frames. (This is a slightly longer way of saying what haushofer said above. It's also an FAQ in the STEM learning section of this forum https://www.physicsforums.com/threads/rest-frame-of-a-photon.511170/).
Sure. Just use the Lorentz transform or the spacetime interval or even the simplified time dilation calculation. Whatever threshold you set as "much shorter than 8 minutes", there is some velocity which can be calculated and, if astronaut Zippy goes that fast, his recorded time will be "much shorter than 8 minutes". For example, if you say that "1 minute is much shorter than 8 minutes" then as long as Zippy goes .9922 c or higher then the measured time will be less than 1 minute.Canada Bob said:Appreciated, that the photons time will be different, but, "much" is a moveable feast, shouldn't it be calculable ?
DaveC426913 said:If you're not satisfied with the correct answer, what kind of answer are you looking for?
Canada Bob said:Hello Zapper, I guess the "problem" is, we aren't all on the same rung of the ladder, or even on the same ladder {of interest}. I'm a retired marine engineer with a curiosity about certain elements of the cosmos. I had hoped that my question, presented in layman's terms, might have solicited an opportunity for someone to enlighten me in similar terminology rather than present some egotist the opportunity to show how vastly superior they are to folks.
When folks have approached me requesting my expertise I have never looked on them with disgust, disregard or disrespect, just because they don't know what I know.
I don't have an appetite or a need to do that, or a frail enough ego to seek to put people down.
Buckethead said:my take on this is that since a photon never expires, one could say that its time has stopped for all eternity.
A photon is a fundamental particle that makes up light. It has no mass and travels at the speed of light.
A stopwatch is a timekeeping device used to measure the duration of an event.
No, a photon is a particle and does not have the ability to hold or use a stopwatch.
It is a hypothetical scenario and cannot be accurately answered. However, if a photon did have a stopwatch, it could potentially measure the duration of its own travel at the speed of light.
As mentioned earlier, a photon is a particle and does not have the ability to use tools or devices such as a stopwatch. It is also constantly moving at the speed of light, making it impossible for it to use a stopwatch in any practical way.