Is the "arrow of time" related to the expanding universe ?

Question

Is it possible that the irreversibility of time is related to the continuous expansion of the universe which is translated
into entropy ? How do you feel about creating a computer program simulating an environmental expansion where the environment is digital ? Such model will include digital people/entities which positively interact with each other but also negatively interact with digital pathogens (elements who are constantly bumping into them, multiply and trying to destroy them, and the faster is the expansion, the more aggressive will be this negative interaction between the digital people and these pathogens. The expansion also weakens the internal structure of the digital units and in time, they will be defeated by the pathogens. In such model, philosophical concepts of aging, chances to be involved in an accident and so on, could be presented. The operator will control several parameters of the model, such as: time and speed of the simulative expansion.

Answer 1

This was a hypothesis that Hawking has thought about and discarded. There are several 'arrows of time'. One is the direction of universal expansion, one is the direction of entropy increase, and one is the direction of consciousness. There are very good reasons to think that the direction forconsciousness and the direction of entropy increase are the same. However, when the thermodynamics is done, there is no direct correlation between entropy increase and universal expansion. Essentially, in a closed universe, entropy would continue to increase until almost the instant of the 'big crunch'. In open universes, entropy could increase for either expansion or of contraction.

Your model is not a very good model for how universal expansion interacts with the very local aspects of biological organisms. Biology occurs on a scale that is many orders of magnitude smaller than scales where universal expansion is relevant. Even on the scale of our galaxy, the universal expansion is insignificant.

Answer 2

To your initial question, yes, they are related in the sense of having a common cause. The Big Bang resulted in both the expansion thereafter and the initial low entropy state that created a time arrow. Despite some speculation on the matter by Dr. H, as pointed out, the expansion itself is not thought to be the cause of the arrow, per se. The real questions then are how the Big Bang got started in the first place and why was its initial entropy low. These questions are still open.

Answer 3

What happends if the universe stops expanding...?

At this point, we don't know if the universe will kepp expanding forever, or if it'll stop or even begin to reverse...... (What I mean is the opposite of expanding).....

Since we haven't been able to figure out the total mass of the universe, all we can do is, point out the possibilities...
If I understand you correctly, then this would mean that if the universe stops expanding, then time stops....all life stops.... I have a hard time figure that one out, because I don't see the link between time and the universe expansion... It's like, as long as you drive your car, the time is running, and when you stop the car, then time stops as well...? No... I don't think so.

I think there was an experiment, that had something with Einsteins relativity theory, when you syncronise to whatches. One is on the ground. The other is in a plane, that travels really fast for a periode of time. When you after a while compare the two whatches, then it shows that the relative time in the plane, (the watch) is slower, compared to the one on the ground....

The faster you go, the slower the relative time will be...

I've allways imagened time as a "constant" factor. Time is something that is! But relative time, is something that you allways compare to "the constant"....

Hope this makes sense...anyway...it's just a thought....

Answer 4

Nothing in the local Universe is expanding. We are not expanding, the Earth is not expanding, the Solar System is not expanding, the Milky Way is not expanding, the Local Group of galaxies is not expanding, and the local supercluster is not expanding. Beyond that, beyond about 500 million lightyears, things are expanding. So, it's a little hard to believe that expansion has anything to do with the dynamics we see locally.

There is no reason to believe that a collapsing Universe would have reverse time---it would still have increasing entropy.

Answer 5

And What do you Plan on proving with this Digital Universe of yours. I mean we all know that the world is getting bigger and it will end one day. So to create such a Theseus is a complete wast of time.

That's just my thought.

Answer 6

Research on such "God" models is going on.

Answer 7

That program sounds like a good weekend project. Let us know when you're done.