Deriving Formula for Surface Area of Black Hole

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Homework Help Overview

The discussion revolves around deriving a formula for the surface area of a black hole using dimensional analysis, based on principles from Einstein's theory of general relativity. The problem involves the constants of the speed of light and Newton's gravitational constant in relation to the mass of the black hole.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning

Approaches and Questions Raised

  • Participants discuss the formulation of an equation involving the constants c, G, and M, suggesting a structure for the surface area in terms of these variables. Questions arise regarding the determination of the exponents in the proposed equation to ensure dimensional consistency.

Discussion Status

Some participants have offered guidance on setting up the dimensional analysis, while others express uncertainty about the problem's clarity. There is an indication that multiple interpretations of the problem may exist, and at least one participant claims to have reached a solution.

Contextual Notes

There are references to specific coursework and potential confusion regarding the problem's requirements, indicating that the context may involve academic constraints or expectations.

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Homework Statement



Einstein's theory of general relativity is relativistic model of gravity. "Relativistic" means it involves the speed of light, c; "gravity" means it involves Newton's constant, G. Use dimensional analysis to derive a formula for the surface area, A, of a black hole of mass M, up to a dimensionless proportionality constant.

Homework Equations



N/A

The Attempt at a Solution



I have little idea of how to tackle this question. Any sort of help would be appreciable.
 
Physics news on Phys.org
Can anyone be of help?
 
Bumping up again.
 
werg lol phys 121 assignment 1 question 3 lol... hahaha waterloo university right?
 
I couldn't do the last Problem... What did u get for (a) and (b)
 
As far as I can tell, the idea is to propose something along the lines of:

A= k*c^x*G^y*M^z

Where k is a dimensionless constant.

Then figure out what the exponents x,y and z must be so that the right hand has units of area (length^2). You should come up with a system of equations with only one solution.
 
I ended by figuring it out, thanks Proggle anyway. The question is kind of obscure and the solution isn't very intuitive.

Yes Karma I go to the University of Waterloo, I figured the same with you by your car race question.
 

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