In a statistically mechanical intergalactic space with (noninteracting) hydrogen atoms of average density 10^-5 atom/cm^3, with age 10^17 seconds, radius 10^28 cm, and temperature 3 K, what is the maximum radius void of matter to have existed given those spacetime parameters? That is, create a random walk model to describe the maximal absolute void volume that classical intergalactic spacetime has ever allowed.

Let me consult with a physics professor and get back to ya on that one

(4/3) x pi x (10^26)^3

Hrm, I'm wondering if you just baffled me with bs.

Radical, my guess is more on the scale of ~centimeter or ~meter.

Is this a statistical avg. ans.? I never was good at statistics and since I like Las Vegas, I guess I don't believe in them.

Just aman

Yes, averaged over the given age and radius.

You are asking what the maximum is, but you are saying thats what the they have to be... why dont you just take the radius and develope it into a spherical shape (??).... something like radical edward did. or am i looking at all this the wrong way.

Originally posted by quantumdream

Radical, my guess is more on the scale of ~centimeter or ~meter.

 

they might have all decayed into energy. leaving absolutely no atoms.

 

 

you never know.

When was the last time that the Earth's atmophere (even a few atoms of it) decayed into energy?

 

Proton (hydrogen ion) halflife is greater than 1000 times the age of the universe!

matter anti-matter collisions.

the half life is only a statistical thing though. Every uranium atom on the planet could simultaneously decay tomorrow at 2:55pm. The probability of it happening is vanishingly small, but still finite.

Even if you calculate a number of hydrogen atoms over an area at a temperature, it's a moot calculation since physics seems to point to a Higgs boson particle or field that is in all space. That is what CERN is looking for now. There is no true void according to physics right now. Something gives particles mass and something keeps the space we experience stable. A void would have to be a lot smaller than the universe of the Higgs boson.

Just aman

I should have said "void of baryonic matter" (not to consider neutrinos, other WIMPs, or exotic particles). By classical, I mean non-virtual as well. The percentage of hydrogen decaying in intergalactic space is negligible for this problem.

okay, well they could all get to the same place, giving the same answer if they're non-interacting. Though the probability would be negligably small, as is the probability of them all decaying, the proability is still finite.

One more time,

create a random walk model to describe the maximal absolute void volume that classical intergalactic spacetime has ever allowed.

Brush up on your random walk!

Why would there be a limit, if you consider the area the lies beyond the fartest point matter created in the big bang has moved from the point of origin?

The parameters I gave define the observable universe, whose age, dimensions and temperature closely outline current hydrogen populated intergalactic space.

The parameters I gave define the observable universe, whose age and dimensions closely outline current hydrogen populated intergalactic space.

Originally posted by quantumdream

One more time, Brush up on your random walk!

 

what's the point? it would just spit out the same answer I gave. If you're looking for an average on the other hand.....