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Knowledge_Seeker
2007-Jan-15, 04:31 AM
I am borrowing this quesiton from another website because I believe there will be better answers over here, thank you in advance:

Does a traveling light particle, traveling at the speed of light become trapped in time? If the theory of relativity is true then as a object travels near the speed of light, time slows down. Once that object reaches light speed, time stops. If time stops then the eight seconds that a light particle takes to reach earth from the sun would become a infinite amount of time relative to that particle, meaning that the particle never reaches earth. How can something both happen (particle reaches earth) and not happen (particle is frozen in time) at the same time?

01101001
2007-Jan-15, 04:53 AM
If time stops then the eight seconds that a light particle takes to reach earth from the sun would become a infinite amount of time relative to that particle, meaning that the particle never reaches earth. How can something both happen (particle reaches earth) and not happen (particle is frozen in time) at the same time?

If time "stops", if the photon's pocket watch changes not between leaving the Sun and arriving at Earth, I wouldn't say time was infinite for it but that time was zero for it -- that it reaches Earth in no time at all, instantaneously, for it.

It's not a case of something both happening and not happening, but more a case of everything happening at once, for the busy little photon -- and if time elapses not, isn't that what you'd expect?

Sam5
2007-Jan-15, 05:32 AM
I am borrowing this quesiton from another website because I believe there will be better answers over here, thank you in advance:

Does a traveling light particle, traveling at the speed of light become trapped in time? If the theory of relativity is true then as a object travels near the speed of light, time slows down. Once that object reaches light speed, time stops.

The time dilation theory suggested by Lorentz in the 1890s was that the oscillation rate of an atom slows down the faster it travels. He used atoms as fundamental atomic clocks. He surmised that the speed of light was a limiting speed for atoms. Light is not an atom.

astromark
2007-Jan-15, 06:14 AM
If the photon were to be able to comprehend the passage of time it would reach planet Earth from the sun in an instant. BUT,! It is not, nor does it have any comprehension of time. ( or anything else for that matter. )We Earth bound inhabitants can observe that that light has taken 8.25 seconds to travel that path. We know this very accurately because the speed of light can be tested and, has.
Where did you get the idea that an infinite number for the perceived journey,?

cjl
2007-Jan-15, 07:30 AM
I am borrowing this quesiton from another website because I believe there will be better answers over here, thank you in advance:

Does a traveling light particle, traveling at the speed of light become trapped in time? If the theory of relativity is true then as a object travels near the speed of light, time slows down. Once that object reaches light speed, time stops. If time stops then the eight seconds that a light particle takes to reach earth from the sun would become a infinite amount of time relative to that particle, meaning that the particle never reaches earth. How can something both happen (particle reaches earth) and not happen (particle is frozen in time) at the same time?
If you look at it from the particle's point of view, there is also distance compression to take into account. As time slows, the distances shorten, and for the speed of light, all distances are zero and all times are zero.

Jeff Root
2007-Jan-15, 07:33 AM
I'm just gonna agree with Zero, Sam, Mark, and cjl.

There is no "infinite amount" of time or anything else involved.
An outside observer sees a photon created at the Sun and take
eight minutes to reach Earth, where it is absorbed. The photon
would see itself born in the Sun and dying on the Earth in zero
time, so it never has any opportunity to experience anything.

Ha. Your question said "eight seconds" instead of "eight minutes"
for light to go from the Sun to Earth, and Mark repeated the error.
I barely caught it myself. About 8.3 minutes is the correct time.

-- Jeff, in Minneapolis

alainprice
2007-Jan-17, 01:11 AM
There is no "infinite amount" of time or anything else involved.
An outside observer sees a photon created at the Sun and take
eight minutes to reach Earth, where it is absorbed. The photon
would see itself born in the Sun and dying on the Earth in zero
time, so it never has any opportunity to experience anything.

-- Jeff, in Minneapolis

Very well said. I can't agree more; the photon never knew it existed.

Mister Earl
2007-Jan-17, 09:29 PM
Interesting. Considering the reference frame of the time dimension, light doesn't exist. Or, maybe, and I realize this is a stretch, here... but maybe light and time are two different flavors of that dimension. Like left and right in a one dimensional frame. Left and right, time and light.
#EDIT# Bad analogy, I didn't mean to suggest they are opposing, but instead mutual components of.

Jeff Root
2007-Jan-18, 06:24 AM
Mister Earl,

I kinda sorta maybe agree with you to this extent: For many
years I have had the notion that time is a factor in everything
that happens, but the only thing in which time is the only
factor is the distance that light travels. That's just a notion.

-- Jeff, in Minneapolis

Mister Earl
2007-Jan-22, 06:18 PM
Yeah. I've been trying to wrap my head around the whole time/light combo for a while now. I've gotten some crazy ideas I'd rather not voice, and have succeded in cultivating a rather spectacular headache.

I'll tell you one of the crazy ideas, just so you can see how far off base I've gotten hehe..

If light/time are intertwined somehow, then what effect would we observe on time if photons are absorbed? What would happen if you put a chronometer inside a laser dump box?

#EDIT# Not really looking for an answer, here, of course. Just showing you all what's been running between the dust mounds and the cobwebs up in the ol' braincase.

astromark
2007-Jan-22, 06:53 PM
Stumpy thumbs . . ., and brain, Yes minutes not seconds . . ., Oops thank you,.Jeff.

Wayne McCoy
2007-Jan-22, 08:49 PM
Here's a question on time and light -- when an electron bound in an atom absorbs a photon with enough energy to cause it to jump orbitals, how much time is involved in the jump? Is it "instantaneous", or on the order of 10^-43 sec? Is it even measurable, given the precise energy the photon imparts to the electron?

Squashed
2007-Jan-22, 09:25 PM
Here's a question on time and light -- when an electron bound in an atom absorbs a photon with enough energy to cause it to jump orbitals, how much time is involved in the jump? Is it "instantaneous", or on the order of 10^-43 sec? Is it even measurable, given the precise energy the photon imparts to the electron?

Would the answer be analogous to the ol' ping-pong balls in a tube example of electricity flow in a wire? The tube is full of balls stick another in and how fast does a ball appear at the other end?

If electrons are made of photons and the size of the electron cloud size is a function of the wavelengths then the diameter of higher energy state would be achieved in the amount of time for the photon's entire wavelength to be absorbed into the cloud.

Quantum theory says it is instantaneous but who knows ... anyone??

Thomas(believer)
2007-Jan-22, 10:07 PM
I think when you "ride on a photon", you would have they feeling that time stands still, because you don't see anything. The first photon you will see, will be your last.
Furthermore I think that QM says that things get fuzzy when this happens;
time and even the speed of light are no longer well defined measurable quantities by Heisenberg's uncertainty principle. What is half a photon?

timeless
2007-Jan-23, 03:10 AM
If time stops when you travel the speed of light, how far have you gone when you decide to stop? Kind of a paradox...

Jeff Root
2007-Jan-23, 04:33 AM
timeless,

It isn't a paradox because you can't decide to stop. Something else
has to stop you, otherwise you keep on going forever.

-- Jeff, in Minneapolis

Mister Earl
2007-Jan-23, 02:48 PM
I think he means that if a photon is never absorbed, it is nearly eternal. Yet, from the photon's frame of reference, it isn't even aware of its own existance.

timeless
2007-Jan-23, 02:49 PM
timeless,

It isn't a paradox because you can't decide to stop. Something else
has to stop you, otherwise you keep on going forever.

-- Jeff, in Minneapolis

If I can decide to travel the speed of light, how come I can't decide to stop?

Jeff Root
2007-Jan-24, 08:40 AM
If I can decide to travel the speed of light, how come I can't decide to stop?
Photons don't have brains.

Even if photons did have brains, they wouldn't be able to use them
because no time passes for them from the instant they are created
to the time they are absorbed.

You could step into a transfer booth and have your body converted
entirely into photons which are transmitted at the speed of light in
any direction you choose. But in the form of photons, you are not
alive-- you have been changed into a transmitted record of yourself.
The photons may be a complete and perfect record of everything
you were at the instant your body was scanned, but the photons
can't do anything except keep moving at the speed of light until they
are absorbed-- hopefully by the receiver of another transfer booth.

-- Jeff, in Minneapolis

swansont
2007-Jan-24, 12:05 PM
Here's a question on time and light -- when an electron bound in an atom absorbs a photon with enough energy to cause it to jump orbitals, how much time is involved in the jump? Is it "instantaneous", or on the order of 10^-43 sec? Is it even measurable, given the precise energy the photon imparts to the electron?

It's not precise, though. The transition has a width to it, governed by the Heisenberg uncertainty principle. A long-lived state has a narrower emission or absorption line than a short-lived one.

I have a vague recollection that someone claimed to have measured the time of the "quantum jump" but a quick search has yielded no results.

Blue Fire
2007-Jan-24, 05:32 PM
I find the following perspective to be helpful:

All things travel through spacetime at the speed of light, c. It so happens that light travels entirely through space and not at all through time. Other things move through entirely through time and not through space. Still others travel through time and space, some more through time than space, and some more through space than time.

This is similar to how you can drive a car entirely northward and not at all eastward. Say that your speed is 50 mph. You are going 50 mph northward and 0 mph eastward. You can then see that other folks could make a 45 degree turn and continue driving 25 mph northward and 25 mph eastward. Still others could drive 50 mph entirely eastward and 0 mph northward. Or 30 mph north and 20 mph east, etc.

So, if you are sitting still in your computer chair (neglecting the motion of Earth, etc. for the sake of argument), you are moving entirely through time and not through space at all. If you board a rocketship to Mars, then you begin moving a bit through space and a bit less through time. As you accelerate, you move faster through space and slower through time.

cjl
2007-Jan-25, 01:57 AM
That's a fairly interesting analogy (although your math is wrong - a^2 + b^2 = 50^2, if you want it to always equal 50mph, not a + b = 50)

Blue Fire
2007-Jan-25, 06:51 PM
That's a fairly interesting analogy (although your math is wrong - a^2 + b^2 = 50^2, if you want it to always equal 50mph, not a + b = 50)I stand corrected. Thanks to Pythagoras! :wall:

Peter G
2007-Jan-25, 11:04 PM
Factoring in the earth's rotation, our heads (those of us not living at the poles) will have traveled faster over the same period of time as our feet, simply from spending more time just a bit further from the axis. The taller you are, the greater the effect would be. This explains Shaquille O'Neal's strangely baby-ish features.

Kaptain K
2007-Jan-26, 10:18 AM
Squashed, How many times, in how many thread, do you have to be told that electrons are NOT made of photons?

Mister Earl
2007-Jan-26, 04:02 PM
I think he's postulating an ATM theory. If that is the case, then he needs to make his case in the appropriate catagory.