The universe is expanding; is this the only or just the best reason to say there has to have been a beginning?

Question

*reads betwenn the erudite lines*

So, seems like most are saying yes.......!?!

Answer 1

It really doesn't mean there was a beginning.  What if prior to expanding, it was contracting, and then when it got small enough it just began expanding again.  And it's been happening like that forever?  so eventually it will hit a point where it will start to contract again.

Answer 2

I think what you are asking can be answered this way --- if the universe is expanding and you run time backwards it was much smaller billions of years ago-- and would have originated from an infinity tiny "singularity".

http://www.big-bang-theory.com/

Answer 3

That was the best reason to state a Primordial Atom Hypothesis.

Since then, we have added the scientific knowledge from all branches (e.g., physics, chemistry) and compared the result of the theory that was created in this fashion (called the Big Bang theory) to the observations. We are able to explain what we observe, and what we observe does fit with the theory.

So now, there are lots of other observations to support the theory.  The expansion is simply the original observation that started the process.

Here is the clincher:

Based on the present theory, there was a time before which the word 'before' makes no sense.  Most people (even scientists) call that a beginning.  The theory does not care what we call it, it simply shows that the word 'before' cannot be used in a way we can understand.

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I reword my answer to give an answer with a different bias:

If we could prove that expansion does not exist, then the entire Big Bang theory falls flat and the idea of a beginning will be very difficult to support (we still have the observation of the Cosmological Microwave Background radiation setting a universal "time stamp", showing that the universe had a definite 'before' and a definite 'after' -- not enough to actually prove a beginning, but still a very good hint that there could have been one).

Proving that expansion does not exist may prove difficult.  Einstein's initial reaction was to put a cosmological constant in his equations to "prevent" the universe from (mathematically) being forced to expand.  After a while, facing the numerous observations, he removed the constant, calling it the biggest mistake of his life.

Even Fred Hoyle, who refused to believe that the universe had a beginning, felt forced to propose a different theory that still had expansion, even though his universe had no beginning.  

His theory required that the universe always be around the same temperature (on average).  It is the Cosmological Microwave Background radiation that did in his theory (the radiation was emitted when he universe was around 3000 K, the Steady State universe had to remain less than 10 K in temperature).

Answer 4

We know the universe is expanding because of every galaxy has a red shift (moving away) but galaxies themselves are not expanding its all the space between the galaxies which is a lot of space. It doesn't sound like it makes a lot of sense but scientist can't explain it entirely either.

Answer 5

When Edwin Hubble discovered that the Universe was expanding, it gave rise to the idea of "running the movie backwards", as it were.  Once the implications were realized,  further work was done, as it always is, to confirm the findings.  All subsequent observations have done just that, and although doubtless over time the picture will be modified, the basic premise of the Big Bang seems to be right.  There have been attempts to make observations fit other scenarios, but nothing has been as successful as the BB.

Answer 6

*reads between the lines*

No, you can't claim evidence for the existence of God by pointing at the universe's expansion.

Answer 7

No, it means that the light that we are receiving from far away objects has been "stretched out" (I.E.: red shifted) as if empty space itself has expanded.