I've tried to get to this several times, to no avail. Google shows it, but site doesn't seem to work. Is anybody else having trouble? I'd like to see this.
No worries! I started another thread and got some interesting discussion. At some point I have to dig into the math, but at the moment I'd like to get some pictures in my head that are at least consistent with the math.
BTW: the folliation pixes are cool, but make my head spin. I will...
Thanks for the clarification, Bapowell. I'm interested in understanding more about the time slicing you mention. This may not be the place for such a discussion, but do you have a good reference or pointer? I will try some more googling.
Dave
First, I think it is cool that we have measured the lower bound on the hypersphere.
But I am still trying to figure out how to apply the balloon analogy. (perhaps I am personally in a dense state.) So here's a few questions:
1) Is the balloon the entire universe or just our observable...
"The whole universe was in a hot, dense state, when nearly 14 billion years ago expansion started .."
The big bang (BB) is often recapitulated by noting the times when the universe was the size of a proton, or the size of a grapefruit, or the size of our solar system. This is most easily...
Clearly gravitiy and time are interconnected Max, but nobody is going to know exactly what you mean by 'a drag sort of way'. If you want some more insight, you should google some of the materials on general relativity. There are some very basic models for how gravitiy and time interact. And...
Okay, I was thinking of that anyway. But it does seem that 'what's beyond the observable universe' has to have a lot to do with what actually happened when BB started. On the other hand, the eventual evolution of bunny rabbits hopping around pastural fields also has a lot to do with the BB...
Okay, so the notion that there was an infinitely dense, infinite mass singularity that effectively exploded is just a holdover from the popular notion that the BB was just a really big bomb. The actual model says that the whole extent of the universe was extremely hot and dense, and once the BB...
If I imagine that I am the center of the universe (my wife suggests that this is often the case), and everything extends only to the 45billion lyr radius, then density calculations of the universe make some sense. The total matter/energy in that sphere is pretty big, but finite. So the...
So far, we haven't been able to do a lot of experiments on black holes, and that's a shame. Even the most universally accepted notions of black holes are not proven by observation or experiment. [Check out http://en.wikipedia.org/wiki/Hawking_radiation] None the less, according to (my...
Very interesting. This prompts the question: is H constant. When B moves with the Hubble flow to the position of C when we started, is it now moving with twice the velocity?
Related question: in special relativity, Einstein tossed out the notion of simultaneity. How does that work in GR...
Are those two statements the same? "You can't travel to the outside" (which I think I already understood, but maybe not) and " ... you're going down the r-coordinate with same certainty ..."
If I were falling into a really large BH, I could cross the event horizon without hardly noticing...
No problem Mike. It never hurts to question things. I've been wondering for a while why folks were so convinced that the CMB data meant that we lived in a BB universe. (I asked on the forum once and nobody volunteered an answer) What if the average temperature of the rest of the universe was...
Answers.com (http://www.answers.com/topic/general-relativity) has a nice recapitulation of GR history. Einstein didn't presume the expansion of space, but rather assumed a static universe (his greatest blunder). Schwarzschild found the first black hole solution. Friedman found the first...