Following the talk I gave in Second Life about the discovery of the accelerating Universe, we held a couple of Q&A sessions. The original plan was to have questions right after the talk, but the Second Life main grid crashed right at that moment. We all got online about half an hour later, and I held one Q&A session for the people who came back. There was another one the next day.
Troy McLuhan (his Second Life avatar name) logged the session, and has done the hard work of formatting and lightly editing it for web publication. You can find the transcript of the Q&A session online here.
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Well done, Rob Knop. And good transcribing, Troy McLuhan.
I read it all, both as a former Adjunct prtofessor of Astronomy, and someone who's recently taught energetic highschoolers. It reminded me of caltech symposia for the public, or for families of alumni, where I know all the content, but appreciate the clarity of exposition, the good teaching, and the feedback from the audience.
Kudos all around.
Interesting reading (still on going)
[10:18] ToolsRMe Shan: So as the galaxies move further and faster apart, at some point they will exceed the speed of light. At some point in the distant future, our galaxy will be alone. Is that current theory still?
[10:18] Prospero Frobozz: ToolsRMe Shan: sort of.
[10:18] Prospero Frobozz: In fact, its not just our galaxy, but the local supercluster of galaxies that are still bound together.
[10:18] Prospero Frobozz: So well stay together with our nearest neighbors.
[10:18] Prospero Frobozz: But other than that, yes, as the expansion of the Universe gets faster and faster, eventually there will be this lonely isolated group of galaxies thats all we can see.
[10:19] Prospero Frobozz: Quanta: Yes, pretty much :) Except that its a big island. Our galaxy alone has a hundred billion stars.
So basically visible matter (the stuff galaxies are made of) is like a drop of grease (oil) in a baloon. The baloon expands, the grease disperses into globules - but there is never more grease, just more volume.
However Rob, are we not just playing with Russian Dolls again ... the universe expands eternally into infinity. Literally a beginning with no end.
But if there is (was) a beginning or big bang, Lee Smolin will insist that it came from somewhere and that we are merely a sister (or parallel) universe, and that there may be other sister (or parallel) universes created along the way - through any one of the blackholes in the galaxies...
And dare I say, Susskind would insist that we are just one of the universes in a lanscape of multiverses ... and hwever this dark energy (and gravity) interacts with this observable Universe IS where the 'crux' of the matter is.
And you or someone (like I) could postulate that from all possible universes in the multiverse finally emerges one, let us hope it is the one we are in, though few things outside a four score years time frame are ultimately really material to any of us - except of course to speculate or theorize on the physics & maths of the universe around us.