How do we know the universe is a closed system?

Question

Im sure you might be awear of the concept of enthrapy, or disorder. The rule of enthrapy is that it will always increase in a closed system. Well, we have been observing enthrapy in the universe with the idea that it caulifies as a closed system. But how do we really know that? What proof do we have that the universe is a closed system? and is it possible that it is not?

Answer 1

In fact, we don't KNOW that the universe is a closed system. We infer that it is because we don't observe any interaction with any elsewhere. (We might be able to observe an interaction without being observing the elsewhere itself.)

But lots of smart people have compared our universe with a black hole, and we know that black holes evaporate over a time,

dt = M^3 15360 pi^2 G^2 / h c^4
dt = (1.261684E-16 s kg^-3) M^3

For my derivation of this expression, see my Comments on question:
http://au.answers.yahoo.com/question/index?qid=20060913032239AAQXNHZ

Now, from the OUTSIDE the evaporation of a black hole looks like blackbody radiation. Hawking radiation has the same distribution in wavelength as blackbody radiation does, for the same equivalent temperature.

The question is: what would the evaporation of a black hole look like from the INSIDE? And, maybe, the answer is that energy is not quite conserved. Because of the size of our universe (M=2E53 kg), the associated evaporation time is about 1E144 years.

The average rate of mass loss, during all that time, from the whole universe, would be 2E-91 kg/year, or 2E-79 grams per billion years. From the whole universe, one electron or one positron, or photons adding up to about half an MeV, would be disappearing each 5E60 years. The present, instantaneous rate of mass loss would be much less than that, of course. And the universe is only 1.36E10 years old.

The point is, we would not be able to tell the laws of thermodynamics in our universe had an exception which was this small. So there is a theory that predicts that our universe is not strictly a closed system, but that the difference isn't worth making much fuss about.

Answer 2

Dearest Sasha:

What an interesting idea you proposed... "That the Universe is a closed system."

Of all closed systems that I , and others, have observed, the Universe is the one system that does not fit the rules.
For one thing, all closed systems have boundaries or extents which are measureable, and the contents of the systems may be easily cataloged and studied. The universe has no measureable boundaries and the contents have never been fully cataloged and studied. That process will take millions of years to come close, and as far as we know will never be completed. The "observable universe" is 40 Billion Light Years in radius in every direction from us. The Milky Way Galaxy alone contains more than 200 Billion stars, each of which may have from 0 to 10 (or more) planets (with their associated moons) circling about them. Beyone the Milky Way Galaxy there are just thousands of other galaxies, each containing billions more stars with their own planets and moons circling about them. So, the universe is really immense beyond belief, and certainly not catalogable in the normal sense. It is not therefore one of your standard closed systems wherein each item may be studied in depth. What we must do in the meanwhile is look at those things within the universe that we can identify and study, one at a time. We can hope to achieve something worthwhile by doing that.

The problem you face is man's tendancy to observe all things based upon his prior experiences. Read that sentence again. That is the problem. The study of space does not lend itself to rules for things existant here on Earth. Space is not Earthbound, and limited by the normal constraints of an Earth bound existance. Recognize that and you will enter a new realm of understanding.

Answer 3

The universe is a closed system.
Entropy is a chaotic state that increases,but this state is not really chaotic,is a normally evolving universe.
If the universe were not a closed system entropy would never stop,which doesn't make sense.
Spiral galaxies are end stages in the evolution of a universe the center may seem chaotic,but it is a logical process that will eventually lead to the demise of the universe.

Answer 4

There is a theory that light takes a curved path whenever it passes beside very heavy bodies. As it keeps bending at some time or other it has to complete a loop/ Hence it is felt that universe is a closed system!

Answer 5

The answer has as much to do with philosophy as it does with science...perhaps more so.

First, this "rule of ENTROPY" is similar to THIS rule:

All living humans expel CO2 from their bodies, first internally (cell to bloodstream) then externally (blood stream to lungs). Therefor, the presence of CO2 in an atmosphere is proof of the existence of human life...

No one can say that entropy always increases in closed systems, for no one has observed all closed systems.

Also, no one has observed all occurrences of entropy.

To make such a determination regarding the universe is to say, "I am inside a bottle, and because I am, I can define the limitations of the bottle".

"Universe" is an ABSTRACT concept that humans have attempted to define in CONCRETE terms.

We feel comfortable when we believe we understand our limitations and have a sense of control of our surroundings.

Yet many great thinkers have postulated that even "The Scientific Method" is flawed, for it is impossible for humans to observe any given point in the time-space continuum.

Robert Pirsig talks about this in "Zen and the Art of Motorcycle Maintenance".

His thesis is that there is a preexistent and unobservable thing best described as "Quality".

It is interesting that the EARLY Greek philosophers understood this as LOGOS.

When LOGOS is translated in English we get WORD, and we understand it as the thought of the cosmic mind, uncreated, existing eternally within the cosmic mind and inseparable from the cosmic mind.

In Chinese, LOGOS is translated TAO and is understood in a similar way.

However we translate it, the concept can only be accepted, not fully grasped.

Beware of scientific "rules", for they will lull you into thinking that knowledge is not ever-expanding, when it certainly is.

Answer 6

The idea is that the universe is the ultimate device of the space and time dimension and that it is expanding and the space that it takes up is empyness of space itself. Hhhhmmm, Albert Einstein said that. But the laws of Physics state that in order for something to expand it has to take up space. So if the universe is expanding what space is it taking up and how much space is left to expand into before it fills whatever void it is taking up. Hubble stated in 1932 that the doppler effect shows that the space that the universe is taking up is emptyness of itself so..maybe the universe is as large as all space and time therefore infinite

Answer 7

You mean entropy. Yes, the universe is a closed system. The universe is the ULTIMATE system. We have no way of knowing of anything beyond it, and no way of testing anything beyond it, because if something is interacting with (providing energy to) our universe, it is PART of our universe.

Answer 8

We need to think outside of the box (universe). The terms 'closed' and 'open' may not do justice for the condition of the universe.
"We don't even know what we don't know."

Answer 9

It is just an assumption. It is possible that it is not closed.

Answer 10

we dont know. i say its not