# Is time linear or cyclic in a flat, zero energy universe?

1. Nov 28, 2011

### hiddenvariabl

I'm writing a paper for a philosophy elective on the Cosmological argument. One of my counter arguments is that a causal loop (treated as a paradox in the Cosmological argument in favor of a creator) is not a paradox if time is cyclic in nature rather than linear. I treat the fact that the universe is flat with zero energy as a given but something is a little unclear to me. In a flat (and accelerating?) universe, would time be cyclic, linear, or could it be either one? I am personally more inclined to think that time has no beginning or end (cyclic) and is just another dimension and that it's apparent flow is really an illusion.

Am I on the right track here?

2. Nov 28, 2011

### PatrickPowers

The x axis has no beginning or end and in a flat universe is not cyclic.

There is a persistent minority view in physics that allows for two-way travel in the time dimension. It has gained strength lately because it is the easiest explanation for the EPR paradox and Bell's theorem. In our world the "arrow of time" results from entropy, which is a statistical property of larger systems.

I know that Kurt Goedel came up with solutions for Einstein's field equations in which time was cyclic. Unfortunately for the theory it predicts that the universe is rotating, and measurements show that if there is such a rotation then it is very small. You might want to look up "Godel Universe."

3. Nov 28, 2011

### nucl34rgg

How would you be able to experimentally falsify or corroborate the idea of time "looping around?"

4. Nov 28, 2011

### hiddenvariabl

OK, so time isn't cyclic but it doesn't have a beginning or end? I wasn't really thinking of a causal loop in terms of time travel per se. Rather in my argument I'm basically trying to establish a eternalism, wherein time and space are treated as a four dimensional "block" (like J.M.E. McTaggart's B-Theory or the alien race in Vonnegut's Slaughterhouse-Five). In such a case wouldn't the Cosmological argument break down since time would be wrapped up within the universe, therefore saying that a creator was there to initiate the Big Bang "before" would be saying that there was time or space before the Big Bang?

The cosmological argument is as follows:

Every finite and contingent being has a cause.
A causal loop cannot exist.
A causal chain cannot be of infinite length.
Therefore, a First Cause (or something that is not an effect) must exist.

While many argue that the First Cause is God I would argue that the First Cause is the Big Bang since saying "God did it" is a cop-out and a contradictory one at that since it says that the Big Bang requires a God to cause it but God does not require it's own cause. If God can just come into existence on it's own then why can't the Big Bang come into existence on its own?

(I realize I probably shoulda started this thread in the Philosophy section but oh well)