Thread: Dumb Holes

What can we learn about black holes from dumb holes? and what cant we?

Such as the inlet of an aircraft engine when the inflow is supersonic? Even with the SR-71's J58-1 engines, that doesn't happen until the aircraft itself passes approximately MACH .9.

The principal differences are two-fold:

First, a black hole is fully three dimensional, with matter and energy streaming into it from all sides, whereas a dumb hole, also known as a "sonic black hole," must have an inlet and an outlet for the fluid stream through which the phonons are travelling.

Originally Posted by tom

What can we learn about black holes from dumb holes? and what cant we?

Possibly to firm up the theory of emergent gravity, which could help reconcile relativity and quantum mechanics???? I'm not sure, just guessing here....

Originally Posted by tom

What can we learn about black holes from dumb holes? and what cant we?

What? What am I missing, here?

Originally Posted by David E. Eaton Sr.

Possibly to firm up the theory of emergent gravity, which could help reconcile relativity and quantum mechanics???? I'm not sure, just guessing here....

No, a dumb hole is an analog for a black hole. The major difference is that the sonic black hole involves sound and sonic quanta (phonons) wheres we are interested in the behavior of photons in or near a black hole. Supersonic fluids (liquids or gases) have their complications. However, they have the very distinct advantage that we can study them in the laboratory. It is a wee bit more difficult to bring a black hole into the lab.

Originally Posted by MisterMe

However, they have the very distinct advantage that we can study them in the laboratory. It is a wee bit more difficult to bring a black hole into the lab.

As I stated above (I'm not sure, just guessing here.... ) and this was the reason for said guess. Thanks for the update, MrMe....

Originally Posted by David E. Eaton Sr.

As I stated above (I'm not sure, just guessing here.... ) and this was the reason for said guess. Thanks for the update, MrMe....

That's why I responded to your post. Of the responders, your post was closest to the mark.