Carroll discussed on WNYC Programming


Carroll described what this strange fact of physics might mean for everyday idea of time and our place in the universe from the Ted stage. The universe is really big. We live in a galaxy the Milky Way. Galaxy there about one hundred billion stars in the Milky Way. Galaxy there are approximately one hundred billion galaxies in the observable universe. One hundred billion is the only number you need to know the age of the universe between now and the big bang is one hundred billion in dog years. Tells you something about our place in the universe. But we would also like to understand it as it cosmologists. I wanna ask why is the universe? Like this one big clue we have is that the universe is changing with time. If you looked at one of these galaxies and measured its velocity it'll be moving away from you. And if you look at galaxy even further away, we'll be moving away faster. So we say the universe is expanding. What that means? Of course, is that in the past things closer together in the past the universe was more dense, and it was also hotter. If you squeeze things together, the temperature goes up that kind of makes sense to us. The thing that doesn't make sense to us as much is that the universe at early times near the big bang was also very very smooth at early times those hundred billion galaxies were squeezed closer together. And you have to imagine doing that squeezing without any imperfections without any little spots where there were a few more atoms than somewhere else because if there had been they would have collapsed under the gravity. National poll into a huge black hole keeping the universe. Very very smooth. At early times is not easy. It's a delicate arrangement. It's a clue that the early universe is not chosen randomly. There was something that made it that way. We would like to know.

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