[Outcast (OP)]

Gravitational lensing has demonstrated gravity's lateral effect on light (Yay, Einstein!). It would seem to follow that there is also a longitudinal influence. Gravity obviously can't make light go faster, and I haven't seen a discussion of slowing it down. What about a frequency influence? "Red shift"?

[Kryptid]

Yes: https://en.wikipedia.org/wiki/Gravitational_redshift

[Outcast (OP)]

Yes

Thanks,
Now, if time stops at the speed of light, does a photon exist at its' origin, its' destination, and all points in between...simultaneously?

[Janus]

Yes

Thanks,
Now, if time stops at the speed of light, does a photon exist at its' origin, its' destination, and all points in between...simultaneously?

Time doesn't "stop" at the speed of light(c). c isn't a valid reference frame to which you can apply the Relativity equations to.
Consider the time dilation equation  T = t`/sqrt(1-v^2/c^2).    If you try to make v=c, you get T = t`/0 and division by zero is undefined ( it has no answer).

[Outcast (OP)]

You can slingshot light the same way the Voyager probes gain energy by gravity assist from a passing planet.  Light isn't going to be much effected by Jupiter, but a neutron star might do nicely.

The energy Voyager probes acquired is manifested in its' increased velocity. Where is the increased energy to the light manifested? It can't go faster.

[Outcast (OP)]

Time doesn't "stop" at the speed of light(c). c isn't a valid reference frame to which you can apply the Relativity equations to. Consider the time dilation equation  T = t`/sqrt(1-v^2/c^2).    If you try to make v=c, you get T = t`/0 and division by zero is undefined ( it has no answer).

I'm OK with math fundamentals (mine, not yours, LOL)...and you certainly can't divide by zero..
So as v "approaches" c, time "approaches" a stop, right?

[Halc]

The energy Voyager probes acquired is manifested in its' increased velocity. Where is the increased energy to the light manifested? It can't go faster.

More mass, or shorter wavelength.

I'm OK with math fundamentals (mine, not yours, LOL)...and you certainly can't divide by zero..
So as v "approaches" c, time "approaches" a stop, right?

Light speed doesn't change for light, so in any frame, the magnitude of v is a constant and approaches no other value.

[Outcast (OP)]

More mass, or shorter wavelength.

Blue-shifted?

[Halc]

Blue-shifted?

If it gains energy, yes.  If it loses energy, then red shifted.

It can be done with moving mirrors just as well as with gravity assist.

[Outcast (OP)]

Light speed doesn't change for light, so in any frame, the magnitude of v is a constant and approaches no other value.

I understand c is a constant, you lost me making v a constant. I want v arbitrarily close to the speed of light with time slowing more the closer you get.

[Outcast (OP)]

It can be done with moving mirrors just as well as with gravity assist.

I'm not familiar with adding energy to light using mirrors. You get more light energy out than you put in?

[Kryptid]

I'm not familiar with adding energy to light using mirrors. You get more light energy out than you put in?

If the mirror is moving towards the incoming light beam, then the reflected light will have more energy because it received a transfer of energy from the mirror. The mirror, in turn, loses some kinetic energy and slows down. The opposite is true if the mirror is moving away from the light beam: the light loses energy upon reflection and the mirror speeds up.

[Halc]

I understand c is a constant, you lost me making v a constant. I want v arbitrarily close to the speed of light with time slowing more the closer you get.

Well, in a nice frame where Earth is moving at .999c, time is certainly dilated here, but that doesn't make the speed of light different as we measure it with our dilated clocks.  In other words, Earth is already moving (v) at arbitrarily close to c.  Is that what you wanted?

I'm not familiar with adding energy to light using mirrors. You get more light energy out than you put in?

Both the gravity assist thing and the mirror thing are frame dependent changes in the energy of the light, but yes, in a frame where the mirror is moving towards the source of the light, the reflected light is blue shifted, having taken kinetic energy from the mirror.  Ditto with the slingshot scenario.  The exact same situation in a different frame (where say the same mirror is receding from the light source) results in a red-shift of the light, and hence lower energy.

[Outcast (OP)]

Well, in a nice frame where Earth is moving at .999c, time is certainly dilated here, but that doesn't make the speed of light different as we measure it with our dilated clocks.  In other words, Earth is already moving (v) at arbitrarily close to c.  Is that what you wanted?

Don't know. Do we agree time slows as you approach the speed of light?

[Janus]

Well, in a nice frame where Earth is moving at .999c, time is certainly dilated here, but that doesn't make the speed of light different as we measure it with our dilated clocks.  In other words, Earth is already moving (v) at arbitrarily close to c.  Is that what you wanted?

Don't know. Do we agree time slows as you approach the speed of light?

Not exactly.   If  a clock is traveling at near c relative to you, then according to you, more than one sec would pass for you for every sec that passes as measured by the clock.   However, for someone riding along with that clock, it would be your clock that runs slower than his.  For each of you time is progressing a its "normal" rate, while is it passing slower for the other.

[Paul25]

You would expect there to be a length contraction