how old will be a black hole?

Answer 1

I can only assume, (given the marginal English employed asking this question,) that you're asking how long will a black hole live.

A black hole's remaining lifetime is a function of it's mass and nothing else. (Indeed, EVERY property of a black hole is a function of nothing but it's mass: radius, rotation, temperature, hawking luminosity, etc...)

Anyway, the remaining lifetime is a function of it's mass (m) and is given by:

t = k * m^3

Where k = 8.4*10^-17 seconds/kg^3

The formula's actually quite a bit more complicated than that: I've simplified the hell out of it by actually multiplying and resolving the slew of physical constants, (G, h-bar, pi, c) and the canonical formula's given by:

http://xaonon.dyndns.org/hawking/ltm.png

Answer 2

Black holes don't have any set age. Some are older than others. The very oldest would be a type of black hole called a 'micro' black hole that are thought to have perhaps formed just after the universe began, about 13.7-billion years ago.

Answer 3

Oh wow!!!! don't we just love the Hawking Paradox!!!!! The best part is that everything that a black hole sucks in is gone forever....I got some old baggage i wish i could throw in there....How long will one live though if it collides with another and then you have two ? When the heck did it start and what cranked it up? And if we cant tell exactly how old it is then how long it will live is pretty hard. Also in the Hawking formula it takes into account Quantum Physics of reconstruction of the matter...So if it disappears into nothing how can quantum be a factor as we cant reconstruct the thing from nothing...I'm so confused....Let me call Steven and see if he can help me...Good luck from the E...:)

Answer 4

Time slows down so much in the vicinity of a black hole that our normal concepts of space and time don't really apply. Is this a trick question?

Answer 5

Depends. There's this black ho that walks the streets near where I live. I figure she's about 40 or so.