Is the universe an open, closed, or isolated system?

Answer 1

The universe as we know it is expanding and there is no end that we know of,, So I would say that it is wide open,

Answer 2

It can't be open. If it were open, then the now-disproved Steady State theory would be true. A closed system just means a system where external energy (Outside the Universe) can cross into our universe, just not matter.

An *isolated* system, which is the Universe (According to best current theories), means that nothing can cross the boundary. External energy and matter cannot cross over, nor can matter.

However, it must be remembered that this is all theoretical. The truth is we don't know and we probably will never know but it seems like the universe is probably an isolated thermodynamic system. It's the only thing that works with leading theories.

At first glance, from a fundamentalist viewpoint, the universe must be isolated because the universe literally is everything (As a matter of fact, we have no clue about ANYTHING prior to 10^-32 seconds after the Big Bang).

To help visualize:

An open universe would mean there are no boundaries and you can freely enter the "void."
For a closed system, picture a multiverse, where 2 can overlap and "interact" with each other. If they can exchange energy but not matter, it is closed.
A fully isolated system cannot interact whatsoever with its surroundings, so everything beyond the "edge" doesn't exist to us for all intents and purposes.

Answer 3

The Big Bang theory as a theory does not necessarily preclude that the Universe has an infinite volume;Hence an open system. The theory basically presupposes that an singularity hung on nothing and then 'poof' the moon, the sun ,and celestial bodies still hang on nothing.And then the nothing expands. Einstein in his field Equation of general relativity indicated that the Universe is a finite Entity. Hence ;a closed system. This implies that he Universe is a conservative system where mass ,time and volume of its containment obey the law of conservation. Consequently the expansion as per the observed recession velocities of stars and group of stars is just a way of a control system to maintain gravitational equilibrium inside the constricted volume of the Universe. Note ; In Thermodynamics a conservative system is a system where the energy is constant within the system and does not escape.That means Entropy remains contained inside the conntainment of the Universe.Entropy is dissipation of energy due to the work done by hydrogen atoms to convert toheliumm atoms. On earth we use the entropy from the sun. The fact ,that the Universe was a construction by our Creator, indicates that the Universe is not mutually exclusive.

Answer 4

It is hard to picture a universe without boundary but as one respondent mentioned we can think of the universe as a set of points anywhere in space and from each point there is a infinite distance. The term infinite is what boggles the mind. Supposedly the Big Bang started things off. At some point in space this event occurred and expansion began from there. As the universe is without a center there is a contradiction. Maybe the universe is an isolated entity, closed or open. From the viewpoint of humans and this planet, our solar system and galaxy Newton and Einstein still prevail.

Answer 5

It's an open space. There is no way it can be closed or isolated. Our Universe is continuously expanding since the Big Bang 13 or 14 billion years ago, so it must be open. Otherwise, it could have exploded any time in the past like a balloon if it were closed or isolated. :)

Answer 6

If the universe is only one portion of a much greater Multi-verse (or whatever else the newer theories try to concoct), then we'd have to determine if there is a perfect closure to the universe we inhabit (in which case it is isolated) and if the closure belong to our universe (in which case the universe is closed).

Presently, the universe appears infinite in spatial dimension (in 3-D). Which means that from any point in the universe, and for any finite distance you can conceive (however large), there are points of the universe further away that this distance in all directions. This makes the universe open by definition, whether it is all there is or it is part of a multi-verse.

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Space-time is not infinite in all dimensions. There appears to be an edge in the past at 14 billion years (or so). It is the "co-moving" 3-D universe that appears to be infinite. However, we cannot see anything that is "co-moving" because light has a finite speed: everything we see in the universe is as it was, not as it is.

Answer 7

Some of these answers seem strange to me. No matter how big the universe is now or how big it will get, is irrelevant. The only relevant thing in determining if the universe is open or closed is the amount of matter. Is that amount large enough for gravity to pull everything back together again or not?

Answer 8

No one knows. Science hasn't come up with an answer yet.

Answer 9

Closed, because EVERYTHING is INSIDE it