What does light feel about its motion?

[Munim]

What is the nature of the motion of light with respect to itself? Does it experience time and displacement? 

[swansont]

Relativity doesn’t afford us the ability to say; light is not in an accessible frame of reference, so the transforms do not work. 

[MigL]

50 minutes ago, Munim said:

What is the nature of the motion of light with respect to itself

Without any reference, like air resistance, ir points passed, such as empty space, would you feel motion or displacement ?

I assume it feels a little stressed from the stress-energy-momentum tensor forcing it to change its path through curved space-time around massive bodies.
Bad pun ??

[exchemist]

1 hour ago, Munim said:

What is the nature of the motion of light with respect to itself? Does it experience time and displacement? 

In theory it does not experience time (time dilation -> ∞ as v -> c).

Absent any sense of time, it seems to me that "experience" has no meaning. 

Edited 8 hours ago by exchemist

[swansont]

1 hour ago, exchemist said:

In theory it does not experience time (time dilation -> ∞ as v -> c).

Absent any sense of time, it seems to me that "experience" has no meaning. 

It’s undefined. You can’t use the Lorentz transform to shift between an inertial frame and that of a photon, and back.

[geordief]

1 hour ago, MigL said:

Without any reference, like air resistance, ir points passed, such as empty space, would you feel motion or displacement ?

I assume it feels a little stressed from the stress-energy-momentum tensor forcing it to change its path through curved space-time around massive bodies.
Bad pun ??

Would  it rather see the world moving (jiggling) and itself just traveling in a "straight  line"?

Would it experience the alternating magnetic/electric fields or do they disappear  in its "own frame"?

[swansont]

2 hours ago, geordief said:

Would  it rather see the world moving (jiggling) and itself just traveling in a "straight  line"?

Why jiggling? (The sinusoidal depictions of E & M fields are the field strength, not their trajectory, if that’s what this is a reference to)

[geordief]

43 minutes ago, swansont said:

Why jiggling? (The sinusoidal depictions of E & M fields are the field strength, not their trajectory, if that’s what this is a reference to)

No it wasn't (but I am under no illusion as to how nonsensical  my notion is)

The jiggling  was  me imagining the whole universe moving left/right /up/down as the light was the only actor moving in a straight line  .(is that a bit reminiscent of the  world spinning around the famous ,presumably stationary  bucket of water?)

The e/m fields  observation was an afterthought -or a second thought as to how they would seeem to the photon itself (wouldn't exist?)

ps yes  I think I understood that  they were field strengths  and not trajectories but  would they exist for the photon?

If there is no valid frame of reference for the photon does that mean we can't ask any questions  as to what is going on there even if they seem ridiculous?

 

 

 

[MigL]

In empty space, a photon would not know it is moving, as it is moving at constant velocity, and there are no reference points for it to discern its velocity or distance travelled.
Further, it would need to interact with any reference point, so it needn't be totally empty space

[swansont]

5 minutes ago, geordief said:

ps yes  I think I understood that  they were field strengths  and not trajectories but  would they exist for the photon?

Yes. It’s still EM radiation.

5 minutes ago, geordief said:

If there is no valid frame of reference for the photon does that mean we can't ask any questions  as to what is going on there even if they seem ridiculous?

We can answer questions based on observations from valid reference frames, i.e. ones an observer (with mass) can be in.

[Mordred]

It gets worse than that as ds^2=0 for null geodesics which is another reason for a photon frame being invalid as a reference frame. Its nonsensical answers such as time stopping or the photon existing everywhere at once that makes it obvious on the photon  frames invalidity.

[MigL]

True.
But we can attempt to 'see' what happens to the frames around the photon.
As Einstein did when he imagined travelling along with one, to arrive at SR.