i just thought about this and if thats the case, then our universe isn't infitine? i know they call a circle infinite but what i mean is a circle is a line that keeps going going but never really going anywhere new.
wait a minute a line is infinite not a circle! what!? could the universe that our galaxy is in be inside some black hole?
2006-09-09 07:23:53 · 9 answers · asked by Holly 1 in Science & Mathematics ➔ Astronomy & Space
Down can be defined as the diredtion a cup would fall if you were to drop it--and up the opposite direction. In deep space there is no preference of gravity in any one direction, so there is no up or down. Now up where the satalites orbit there still is an up an down due to gravity; the only reason why the astronauts do not feel it is because they are orbiting the earth at tremendous speeds, causing just enough centrifugal force on their bodies to cancel out whatever gravity. Stephen Hawking once speculated that our universe could be inside a black hole--many other scientists still think this might be true. The bigger a black hole is, the more gentle it is; that is why a black hole as big as the observable universe might not feel very uncomfortable. A small black hole the size of a moon would tear your body to pieces if you entered inside.
2006-09-09 07:31:17 · answer #1 · answered by bruinfan 7 · 0⤊ 0⤋
The topology of the universe is not well understood. It is possible to have a finite universe that "wraps around" on itself much like you suggest with your line bent into a circle. In such a universe, if you travel in a straight line, eventually you come back to your starting point. This is analagous to the surface of the earth having no edge, but being finite.
Here is a nice page about the topology of the universe: http://astro.uchicago.edu/home/web/olinto/courses/A18200/nbower.htm
The universe could be inside of its own Schwarzschild radius. This is the definition of a closed universe that expands for a while and then collapses again into a "Big Crunch"; not even light can escape it and all paths lead to the singularity eventually. Sounds like a black hole to me! I expand on this somewhat incredible conclusion in the following paragraphs, but in short a closed universe that collapses again means that the universe is within its own schwarzschild radius.
If this conclusion sounds too incredible to you, look at the equation describing the Schwarzschild Radius of a black hole, r=2GM/c^2 . .
The radius increases linerally with the mass. But the average density scales as density=mass/(4*pi*r^3) . . . so you end up with the average density dropping very quickly as the mass expands.
average Density = c^6/(32*pi*G^3*M^2).
Now it starts out quite large because of the c^6 (a very large number) in the numoerator and the G^3 (a very small number) in the denominator. But if you add enough mass (and the whole universe is pretty freekin' heavy) eventually the necessary average density to be a black hole drops to comprehensible levels. In fact, if you wanted to make a blackhole about the mass of the universe, the average energy density within would be roughly what we see in terms of matter+dark matter+dark energy.
Read about the schwarzschild radius here : http://en.wikipedia.org/wiki/Schwarzschild_radius
and the cosmological density parameter, omega, http://en.wikipedia.org/wiki/Friedmann_equations#The_density_parameter
2006-09-11 01:20:01 · answer #2 · answered by Mr. Quark 5 · 0⤊ 0⤋
What you are trying to say is that every straight line is the arc of a circle in the limit.Yes?It has an infinite radius. Universe is not in a black hole. A black hole has infinite gravity. Concept of a black hole is very difficult to understand. Also what we know about our universe is only 5% or less since all matter contained in universe is only 5%.Rest is all dark matter about which we know so less.
2006-09-09 14:32:49 · answer #3 · answered by openpsychy 6 · 0⤊ 0⤋
Gravity is what creates the sensation of up and down. Up is a movement in opposition to gravity and down is a movement in concert with gravity. In space there is no gravity so unless you are close enough to a heavenly body (moon, star, planet, etc) to be pulled by it's gravitational force the sensation of up and down is absent.
2006-09-09 14:30:16 · answer #4 · answered by Anonymous · 2⤊ 0⤋
The universe is NOT round... and "up" and "down" only apply when something is near a source of gravity (a star or planet)
2006-09-09 14:35:50 · answer #5 · answered by Anonymous · 0⤊ 0⤋
Every thing was made with one side . The right side.
Maybe?
2006-09-09 14:36:57 · answer #6 · answered by mark h mickey 2 · 0⤊ 0⤋
its actually has all 11 demintions
2006-09-09 14:29:36 · answer #7 · answered by Anonymous · 0⤊ 0⤋
It's flat...stay away for the edges.....lol
2006-09-09 14:25:37 · answer #8 · answered by ? 6 · 0⤊ 0⤋
stop thinking before you burn out your brain cell
2006-09-09 14:30:35 · answer #9 · answered by mr. Bob 5 · 1⤊ 1⤋