ju'iblex

I think you'll get more response in Science and Skep, and I'm sure the folks up there would love to answer all these kinds of questions

goat37

Well... I wouldn't go as far to say that .0000000001% of the universe is actually filled.

They believe that at least a 3rd of the universe is filled with 'dark matter'

That requires more explanation than I am willing to type right now, but I am sure someone else would be willing to (and prolly more accurately) but I will say that if it's 1/3 than it is at least 33%!


Oh, and just for those who didn't know what a 'light year' was, it is roughly 5.88 trillion miles, usually just estimated at 6 trillion miles. (how far light travels in a year)

Jesse

I think you're talking about the fraction of the mass in the universe that's dark matter, while the earlier poster was talking about the fraction of the volume of the universe that contains particles. In terms of volume, the vast majority of the universe is indeed empty space (although it's a little more complicated because of all those virtual particles in 'empty' space...)

notMichaelJackson

JTDC was probably refering to the empty space between protons, neutrons, and electrons, so we probably are only .000000whatever % filled.

goat37

Gotcha..

Well, of course only a small portion of the ENTIRE universe could be filled, seeing as how the infinite universe is expanding, and there exists a finite amount of matter and energy.

So I guess you could actually say that 'empty space' of the universe is actually increasing.

Jesse

Density of Outer Space

Most sources seem to estimate an average of about one hydrogen atom per cubic centimeter of interstellar space (maybe it'd be less in intergalactic space), and according to this article the volume of a hydrogen atom is about 1.4 * 10^5 cubic picometers, or 1.4*10^-25 cubic centimeters, so that'd imply only 0.000000000000000000000014% of space contains atoms. And of course, as notMichaelJackson said, most of the volume of an atom is empty space too...according to this page, "If the nucleus of an atom had the diameter of a dime, the outer edge of the atom would be about 50 yards away."

Rhaedas

The Great Attractor is a real interesting theory. As scientists pieced together the various velocities of the local cluster, it became apparent that they were all moving as if there was a larger object pulling at us all. Unfortunately it just happens to be located on the opposite side of our galaxy, so the Milky Way's center is blocking any possible measurements. I don't even think there's consensus on what size or distance the GA may even be...we just know we seem to be going that way for a reason, against the pull of other clusters.

eh

Current theory suggests an infinite universe would have an infinite amount of matter and energy.

Demosthenes

There's a problem with postulating that the universe is infinite in space and time. If that was true then all stars and other sources of radiation in the universe would have had time for their rays to reach earth. That means the sky would blaze as bright as the surface of the sun. Obviously life as we know it won't survive in such an environment.

eh

The expansion ought to take care of that. Then again, so would the fact the universe is of finite age.