Can One Suspect the Universe has to Be Closed?

Question

chess2226, What Suggests it is Expanding Greater than the Speed of Light?

I'm Sorry, but I'm Asking About What HAS to Be, Not What Might Be.

So, johnandeileen2000, The Speed of Light Can't Be Constant Thoughout the Universe, What does that Imply?

johnandeileen2000, Please allow me to armwave something to you. Starting with a closed universe. Following the track of a photon of light, from it's birth, early in the universe, it would trace out something like a cardioid (at least this is what I used for many years) on it's travel along the surface of an expanding, decelerating universe. Therefore, the universe may be hypercartioid in shape. Using some very simple mathematics for the arc length of a cartioid, one arrives at the equation c=2Ve, where Ve is the expansion of the universe at any point. It is interesting to speculate if velocity of light is dependent on the velocity of expansion of a point.

Answer 1

Red shift indicates that galaxies are separating at a rate greater than the speed of light. At first glance this may seem to be impossible but if two two galaxies are moving away from each other at a speed of more than half the speed of light the apparent rate of separation will be greater than the speed of light

Answer 2

The shape of our known universe can take on one of three forms, according to current thinking. It can be spherical, it can be shaped like a saddle, or it can be flat. The shape depends on the value of omega, the density ratio. [See source.]

Omega is found as a constant of proportionality in the equations that describe the shape of the universe. Unfortunately, no one really knows what the value of omega is. However, more and more bits and pieces of cosmological evidence point to omega <1, but just a little bit; and that implies our universe is almost flat...and ever expanding without end. Omega would have to be > 1 for it to be spherical and closed, and there is little if any evidence of this.

If the universe is spherical, it is closed. Otherwise, it is open as both the saddle shape and the flat go on without edges.

Answer 3

Open or closed? no one knows. Before the discovery of dark energy, this question was considered more answerable than at present. In principle, one could simply measure the mean density of the universe and the Hubble constant accurately and calculate whether or not the expansion had enough momentum to keep going forever (implying openness in both space and time), or not. This prediction, however, required the perfectly reasonable (at the time) assumption that Einstein's cosmological constant was zero. With the prospect of dark energy, though, and with no one knowing enough about it to know how it will behave in the future, all bets are off.

Answer 4

One can suspect anything they want when it comes to the inherent nature of the universe. I, for one, do not believe it is closed though.

I believe that it is open and will continue to expand forever into whatever higher dimensional "space" our universe exists in.

Answer 5

Because it seems to be expanding at past the speed of light, it is for all intents and purposes open for buisness.

Answer 6

It is just closed on Christmas and Thanksgiving eve. Otherwise it is open 24/7

Answer 7

All reality is created by light.

I believe the outer parts might be so negative (black hole conditions) light may not exist. If you have the energy to curb light you have it to curb reality.

Answer 8

Unless destroyed or taken over by aliens, it will disentigrate in about 1000000000000000000000000000000 years