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One lesson of special relativity is:

There is no frame of reference in which a photon is stationary.

We have this beautiful thing in special relativity. Every inertial reference frame is created equal. If you choose an inertial coordinate system, you can do your physics and calculate the evolution of the universe in that coordinate system, and everything will work out just fine. But this is a very special demand, because the coordinate system has to be mathematically well-defined.

So what are you doing when you say "the rest of the universe immediately jumps to the end of time"? You're doing a mathematical limiting procedure. As you travel in the direction of travel of a laser beam, you see the wavelength of the laser increase (redshifted), and you see things in front of you played in higher speed* (blueshifted). So in the limit as your velocity goes to $c$, yes, "everything in front of you plays out all at once". (In the form of infinite frequency light hitting your eyes!)

TheThis sounds really dramatic, but why don't you hear physicists making statements like "the photon jumps to the end of time"?

It's because the physicist is forced to stop herethe limiting procedure at some point. The limit can't be achieved, because it. It leaves you with a mathematically ill-defined "reference frame"/"coordinate system" (whichwhich is not a frame of reference nor a coordinate system) in which you. You can't actually do any physics if you tried to work in this coordinate system. Since coordinate systems are just things humans impose on reality in their minds, this doesn't have any deep meaning.

*(By "see" I really mean "see". With your eyeballs. Sometimes people say "see" as in, "the mathematical positions in your coordinate system". But I mean "see" as in, the photons from whatever is in front of you are blue shifted and hit your retina at a higher frequency)

One lesson of special relativity is:

There is no frame of reference in which a photon is stationary.

We have this beautiful thing in special relativity. Every inertial reference frame is created equal. If you choose an inertial coordinate system, you can do your physics and calculate the evolution of the universe in that coordinate system, and everything will work out just fine. But this is a very special demand, because the coordinate system has to be mathematically well-defined.

So what are you doing when you say "the rest of the universe immediately jumps to the end of time"? You're doing a mathematical limiting procedure. As you travel in the direction of travel of a laser beam, you see the wavelength of the laser increase (redshifted), and you see things in front of you played in higher speed* (blueshifted). So in the limit as your velocity goes to $c$, yes, "everything in front of you plays out all at once". (In the form of infinite frequency light hitting your eyes!)

The physicist is forced to stop here. The limit can't be achieved, because it leaves you with a mathematically ill-defined "reference frame"/"coordinate system" (which is not a frame of reference nor a coordinate system) in which you can't actually do any physics. Since coordinate systems are just things humans impose on reality in their minds, this doesn't have any deep meaning.

*(By "see" I really mean "see". With your eyeballs. Sometimes people say "see" as in, "the mathematical positions in your coordinate system". But I mean "see" as in, the photons from whatever is in front of you are blue shifted and hit your retina at a higher frequency)

One lesson of special relativity is:

There is no frame of reference in which a photon is stationary.

We have this beautiful thing in special relativity. Every inertial reference frame is created equal. If you choose an inertial coordinate system, you can do your physics and calculate the evolution of the universe in that coordinate system, and everything will work out just fine. But this is a very special demand, because the coordinate system has to be mathematically well-defined.

So what are you doing when you say "the rest of the universe immediately jumps to the end of time"? You're doing a mathematical limiting procedure. As you travel in the direction of travel of a laser beam, you see the wavelength of the laser increase (redshifted), and you see things in front of you played in higher speed* (blueshifted). So in the limit as your velocity goes to $c$, yes, "everything in front of you plays out all at once". (In the form of infinite frequency light hitting your eyes!)

This sounds really dramatic, but why don't you hear physicists making statements like "the photon jumps to the end of time"?

It's because the physicist is forced to stop the limiting procedure at some point. The limit can't be achieved. It leaves you with a mathematically ill-defined "reference frame"/"coordinate system" which is not a frame of reference nor a coordinate system. You can't actually do any physics if you tried to work in this coordinate system. Since coordinate systems are just things humans impose on reality in their minds, this doesn't have any deep meaning.

*(By "see" I really mean "see". With your eyeballs. Sometimes people say "see" as in, "the mathematical positions in your coordinate system". But I mean "see" as in, the photons from whatever is in front of you are blue shifted and hit your retina at a higher frequency)

Source Link
user12029
user12029

One lesson of special relativity is:

There is no frame of reference in which a photon is stationary.

We have this beautiful thing in special relativity. Every inertial reference frame is created equal. If you choose an inertial coordinate system, you can do your physics and calculate the evolution of the universe in that coordinate system, and everything will work out just fine. But this is a very special demand, because the coordinate system has to be mathematically well-defined.

So what are you doing when you say "the rest of the universe immediately jumps to the end of time"? You're doing a mathematical limiting procedure. As you travel in the direction of travel of a laser beam, you see the wavelength of the laser increase (redshifted), and you see things in front of you played in higher speed* (blueshifted). So in the limit as your velocity goes to $c$, yes, "everything in front of you plays out all at once". (In the form of infinite frequency light hitting your eyes!)

The physicist is forced to stop here. The limit can't be achieved, because it leaves you with a mathematically ill-defined "reference frame"/"coordinate system" (which is not a frame of reference nor a coordinate system) in which you can't actually do any physics. Since coordinate systems are just things humans impose on reality in their minds, this doesn't have any deep meaning.

*(By "see" I really mean "see". With your eyeballs. Sometimes people say "see" as in, "the mathematical positions in your coordinate system". But I mean "see" as in, the photons from whatever is in front of you are blue shifted and hit your retina at a higher frequency)