gravity and black hole shadow

[bicyclebones]

I submit for consideration that possibly gravity might propagate at the speed of light squared as is suggested in e=mcc. Further, I inquire if a blackhole would cast a shadow? No answer required...think about it.

[apodman]

I submit for consideration that possibly gravity might propagate at the speed of light squared as is suggested in e=mcc.

Gravity propagates at the speed of light (not at the speed of light squared), and Einstein's energy-mass equivalence formula (e=mcc) doesn't apply to the question of propagation of gravity.

In physics, when you multiply quantities, you have to multiply the units as well. When you square a velocity (like c) with units of length/time, you get units of length²/time² which is no longer a velocity and can't be treated as such.

I inquire if a blackhole would cast a shadow?

The black hole would produce gravitational lensing. Light originally headed inside the event horizon would not go past the black hole, whereas light originally headed somewhat outside the event horizon would be bent around it. The borderline between these two areas of light would be projected as the outline of a shadow would be projected, and in a sense would be a shadow even though there is no central dark spot created except close to the black hole. Not similar to but compare with the penumbra of earth's shadow projected into space by the sun - it's not dark, but a shadow has been projected.

[makc]

apodman, the OP said it clearly:

No answer required.

Therefore I am locking this thread at the request of OP