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## Main Question or Discussion Point

I was listening to some GR lectures,and the description of the event horizon of a black hole was the surface at which the escape velocity becomes larger than c. (I'm paraphrasing)

This seems like the event horizon would appear to get smaller the closer you got to it, since the velocity required to get to your location would drop below c, since there was not as much work required to arrive.

Did I misunderstand the way it was described?

Rockets do not start with the full escape velocity, they add velocity as they go. At some point, their V becomes larger then the escape velocity, at their altitude.

Also, the escape velocity is larger than the orbital velocity.

So, forgetting the whole time dilation thing for a minute, would it be possible to orbit through the event horizon at less than c?

If so, having gone inside the event horizon and returning out, couldn't the orbiting object than emit a photon that would be able to escape, since it is now in a location for which escape V < c?

Thanks,

Spizmar

This seems like the event horizon would appear to get smaller the closer you got to it, since the velocity required to get to your location would drop below c, since there was not as much work required to arrive.

Did I misunderstand the way it was described?

Rockets do not start with the full escape velocity, they add velocity as they go. At some point, their V becomes larger then the escape velocity, at their altitude.

Also, the escape velocity is larger than the orbital velocity.

So, forgetting the whole time dilation thing for a minute, would it be possible to orbit through the event horizon at less than c?

If so, having gone inside the event horizon and returning out, couldn't the orbiting object than emit a photon that would be able to escape, since it is now in a location for which escape V < c?

Thanks,

Spizmar