TranscriptQuestion: Do you think the Universe has evolved in a logical way?
Katie Freese: Wow, I think if we try to write down a universe on a piece of paper that was the most simple and the most elegant there is a lot of things you wouldn’t find, so if all the way… all the details intermesh, are very important to for example, allowing people to exist and I mean on the biological level I guess this is obviously that we’re very dependent on respiratory system and all the rest of it, which is not something that you would just invent again if you had a random piece of paper and certainly what we’ve discovered, this sort of pie picture of the universe that you have 4% atoms, dark matter, which I think is the… That is a solvable problem. I think we’re on the edge of solving that one, but then all the sudden this dark energy appeared as a complete mystery. This was on the late 1990s, so I think I was saying around… In the past 10 years, around the turn of the millennium it’s really been the golden age for cosmology from the point of view of data coming in and really affecting our thinking, so this is a very bizarre, probably illogical thing from our current understanding of what powers the dark energy, so the thing that we see is that apparently the universe is not only expanding, we’ve known that for a long time, but also accelerating.
The way this was originally found was by looking at very bright supernovae. These are the explosions of dying stars and these distant supernovae were seen to be fainter than anybody expected and one interpretation was that they’re accelerating away from us and at first it wasn’t clear what really was going on, but that is the consensus picture at this point that this… You have this acceleration driven by this powerful new… Well this is… it’s almost like an antigravity, so whereas dark matter makes up galaxies, it has a normal gravitational interaction, this other stuff has some kind of negative pressure. It pushes things apart and it could either be a new kind of energy density, a vacuum energy density or it could be telling us that our basic equations are wrong and we have to rethink everything, so this one has people very excited and puzzled and it’s not going to be answered you know this one will not be answerer tomorrow, but it’s a big one and it certainly affects the future evolution of the universe as well, so.
Recorded May 7, 2010
Interviewed by David Hirschman