Episode 4: You can try this at home — cosmic expansion

Infinitely dense point in space?
If the universe has infinite occupied space and mass, that would be true. But is it?
And if it is infinite and the Big Bang theory were to be correct, how did space expand infinitely in such finite time?
This is assuming that in such infinite universe, if you travelled in one direction millions of times faster than the universe is expanding (from the two furthest points) for eternity, you would never run out of galaxies and other objects.

Also, at the moment, my unverified idea of "what the universe is expanding into" is that absolutely everything in existence is in an infinite vacuum and the definition of the "universe" is the collection of matter (and antimatter) that exists in it. This matter just expands in this space.

I'm actually gonna think about that question more. All my current knowledge of physics (I'm only in secondary school) is making that the most plausible idea so far. I mean, if the universe is expanding into "empty void", how can we describe this "empty void"? (Working on the idea that the universe is all that exists, including the entirety of space). If it is simply "nothingness", then it doesn't exist. I mean, even empty vacuum is something - it is unoccupied space. It has to have something to it. Then again, it is possibly because it is impossible to explain because it is as impossible to visualise as us viewing a 4 dimensional image.

(just my ideas of this, not necessarily reflecting any other source.)

Thanks for the presentation: Now i could get how the beginning of the universe was look like.
Liz & Bill: You're wonderful.

I like your videos and was around at the time of your first one ... way back when. You have hit on the topic that I find so interesting ... cosmic expansion but still don't get. I had childlike faith in "the big bang" theory where everything started over 13B years ago. Then came the theory about "inflation" that earliest period of time after the big bang where scientists theorized there was a brief period of hyper-expansion ... I could not quite get my head around that. And now the theory that cosmic expansion is uniform, unchanging and everything is moving away from ... everything. Now that I am faced with the cosmic expansion theory I can't picture the beginning. If everything expands away from everything what did the beginning look like?

I like the demonstration with the dots, but I can't geat my head around the idea of space expanding from all points at once...wow!

Is dark energy the primary motor for the universe expansion.

Quite funny Bill; the rising bread should be DELICIOUS.

Please how could I acquire one of this sphere?

Vinicius adds: vfcg40@yahoo.com.br

Thanks. Vinicus