Gravity Contraction = Space Expansion?

If you subscribe to the big-bang, then things are running away from each other and the center. Eventually, they will stop and come back completing the cycle.

In my humble opinion, the 'big bang' theory only makes sense if applied to planets, stars, etc. I believe that the Universe itself has always been and will always be; Finite and Infinite. If the Universe is an object, not a space, then what's it in? Is it particle or wave? Is it as deep as it is broad? I have been asking these questions for 40 years. I studied Astro-Physics while in college, and ended up in philosopy. Philosophers were the first astronomers anyway. Go Figure.

Your observation that you ended up in philosophy is true in all branches of knowledge. Philosophy is ultimate,as it is the study of the fundamental nature of knowledge,reality,and existance. Dictionary meaning of terms,is quoted below,if it can help."Space is vastness of free,unoccupied and continuous area. Universe is all matter and Spcae considered as a whole". The more this topic is discussed,it becomes more "philosophical"

I found Philosophy fascinating. It was not an easy field of study, and many students disliked the courses, especially Eastern Philosophies. I found that it gave Me enormous latitude and room for my own thoughts. If I may respond to your statement "space is vastness of free, unoccupied and continuous area;" can you define 'area?' This is where folks become perplexed. If it is definable, and the Universe is not already occupying it, where does it end? What's on the other side? What transpires at the face of the Universe as it takes up this unknown entity. This is great stuff! The only thing is I could spend the rest of my life trying to figure this out. Einstein spent his dying hours looking for answers to that which goes beyond the theory of relativity!

Huh! Completing the cycle? Will there be another Big Bang? How many before this one? How many after? If the universe is infinite in all directions there is no center! We can only IMAGINE infinity. But we do KNOW that Earth will eventually lose the moon, and our Sun will burn out, after it incinerates the Earth. Best Wishes.

Yes, Yes, Unknown and lots... IF the big bang is correct, then everything was in one place at the same time and exploded. If what we see and measure is representative of all that is, then the universe's material will continue to move away from itself ever slowed by its own gravity. After the pieces stop, they will return to the centre at ever increasing speeds until they meet in a tiny, but fully loaded pinpoint which will explode again.

If you subscibe to the 'Big Bang` you also subscibe to 'inflation`, (where Vel. of expansion exceeded C). This places more than half of the origional material beyond our 'Event Horizon`, (we will never see it or feel its gravitation). Even neglecting this, have you never heard of an escape orbit? - If the velocity is high enough, gravity will not overcome inertia. Current astrophysical opinion seems to be that not only is the velocity great enough to guarantee continued expansion, but that some unexplained force is causing the expansion to accellerate. As of now the consensus opinion favors a 'Big Rip` rather than a 'Big Crunch` for the end of the universe as we know it.

Space is expanding. So even if nothing moves, space is forcing things apart. Read Brian Greene's book "The Fabric of the Cosmos" for the full story. Things will eventually be moving away from each other in excess of the speed of light. They won't be moving faster than the speed of light through space, that's impossible. But since space is "stretching" at an increasing rate, well, just read the book.

This is not my version but Philosophy tells,"Space is Dimensionless and timeless.Space was,is,and will be same,never changes,contains all that can be visualised.Space plus spcae equals space,Space minus space equals space,Nothing and Everything is Space". For those who do not have philosophic bent of mind,this might appear absurd.

Space has properties and as such is a material, not nothing. It stretches and expands, it allows distinct types of motion, it is distorted by mass in a very precise way.

Aren't all of the stars producing heat? And doesn't heat cause things to expand? And are you now going to reply that there's nothing there to expand? Modern astronomy is built upon a modern Ptolemeic system.

After viewing all the above you can easily draw several conclusions: 1. Any hypothesis about universe-space-time-expansion-contraction and so forth, is comparable to "rear ends and opinions", everybody has one! Some accurate,some not. 2. Books = knowledge; books only reflect a record of the author(s) opinions/facts, based on knowledge derived from other books. Therefore,books are best used to create more accurate books which become an even larger collection of opinions/facts.(Newton-vs-Einstein) No footnotes needed. 3. If we were to completely understand the existence of everything and ourselves, then we would know the mind of "God" or whatever is responsible for everything. At this point, the only existence we can truly know is our own.

"At this point, the only existence we can truly know is our own."

And I charge that we don't know that very well, either!

I think therefore I am.... I think?

Hi, I and many others had long held the view that the universe would expand until eventually gravity overcame the acceleration and expansion of the Big Bang and then would start to contract again into a 'Big Crunch'; followed again perhaps by another Big Bang. Many scientists have held this view as well. However recent measurements made in the last decade by more advanced satellites and instruments show in fact that the universe is expanding at an ever increasing rate. Currently they are hypothesizing that the majority of the universe is unseen Dark Matter and Dark Energy that has a repulsive force and pushing everything apart at this ever increasing rate. Personally I don't know how they surmise that this is not still just acceleration from the Big Bang.

Nobody knows why and there are a ton of theories to try to figure it out. Dark Matter, Dark Energy, Curved Universe, Flat Universe, Inflation, etc.

There is a misconception that Physics has a good handle on how everything works, but the truth is there is a ton more to learn.

Any thoughts on the connection between "time" and the expansion of the universe? Speaking in both terms as the unit of measure, and the broader sense of the synonamous relationship between the two. Helluva discussion for Mon am.

No more than metaphysical musing but I think the fact that time moves one direction and space expands (doesn't contract) and entropy always increases is probably realated, but I have nothing to back that up.