black hole question

[hoola]

I see where a black hole can be described by mass, spin and charge. Couldn't another description be the rate of Hawking radiation detected at a standardized distance from the event horizon, or a theorized level occuring at the horizon? Or would that radiation level be a deriviative of the 3 standard discriptions and not independent of them?

Edited February 9, 2017 by hoola

[MigL]

The mass/energy of the Black Hole gives rise to an event horizon of a certain area.

This area can be related to the entropy/temperature of the BH.

So another ( dependant ? ) descriptor would be the entropy/temperature of the BH.

Hawking radiation is a consequence of that property

[mathematic]

For most black holes the Hawking radiation is so small, that it most likely would be hard to detect.

[imatfaal]

I see where a black hole can be described by mass, spin and charge. Couldn't another description be the rate of Hawking radiation detected at a standardized distance from the event horizon, or a theorized level occuring at the horizon? Or would that radiation level be a deriviative of the 3 standard discriptions and not independent of them?

 

There could be lots of other properties (MigL has given one - the surface area of the event horizon) but the point of the assertion is that you can fully describe ALL possible black holes with just three pieces of information. For example, to fully describe a star you need to talk about mass, spin etc but you also need to get into composition, stratification, nearby interactions etc. Any blackhole can be fully defined (ie you know everything you can know about that black hole) with just the mass, spin, and charge. All other characteristics are dependent on one or more of those three properties

 

"Or would that radiation level be a deriviative of the 3 standard discriptions and not independent of them?" Exactly

 

[latex]T=\frac{1}{M} \cdot \frac{\hbar c}{8k_B \pi G}[/latex]

 

H bar, c, G and k_B (Boltzman) are all constants - the only variable is M - mass

 

The luminosity is similarly only connected to the Mass (inverse square) - BTW I think this is only for Scwartzchild blackhole - spinning Kerr (and the others Nordstrum? or is that Donalds bete noire) might be different; but you can still uniquely quantify with just those three characteristics