age of the universe
Feb. 9th, 2010 02:02 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
miriam_eI was just reading a piece discussing the expansion of the universe. The writer was extrapolating backwards to find an estimate of how old the universe is, but the particular passage was written before evidence was found that the expansion looks to be accelerating.
As most readers of my ramblings will know, I'm not fond of the idea that the universe started in a Big Bang. I'm not saying it definitely didn't happen, just that I find it very unconvincing. I've often stated my reservations this way:
I know a lot of people have problems with infinity, but if the universe is infinite in size (something I "prefer" because I find it easier to imagine) then the universe could have been expanding forever but always been infinitely big... just becoming a larger infinity. :) (That pop you just heard was your mind breaking.) Or it could have "bounced" long before reaching the zero point, having previously collapsed to some density limit.
And yes, I know there is other observational data like the makeup of galaxies as we peer back in time with our telescopes, but none of that says conclusively that there was a big bang. It could be that there was a local catastrophic event, or that galactic births follow cycles. We don't really know.
I don't count the cosmic microwave background radiation as "proof" of the big bang. I remember when I was a kid reading science journals the microwave background was at one point considered evidence against a big bang.
My point is not to say what did happen, but to point out that believing there was a big bang seems a mistake. Such belief is based on inferences that always looked to me less than convincing at best, and "magical" thinking at worst. It seems to me that it jumps to conclusions, when there may be other ways of looking at the data.
Just to reinforce my point: I'm not saying a big bang did not happen. I'm just saying I find it hard to swallow, and so long as I can come up with alternatives I'm not going to believe any single explanation... even ones that feel right to me. I reserve judgment. I certainly won't believe something just because others do.
As most readers of my ramblings will know, I'm not fond of the idea that the universe started in a Big Bang. I'm not saying it definitely didn't happen, just that I find it very unconvincing. I've often stated my reservations this way:
"Europe is the center of the universe"Well, I was thinking... assuming the expansion is real and not an error in our deductions, and what we can see of the universe really is expanding non-linearly then it is conceivable that there never was a time when it was a single point-source. If the graph of size against time is a curve that becomes less and less steep further and further in the past then who is to say it ever intersects the zero-size mark on the graph? It could approach forever, asymptotically, some size, not necessarily even a small size.
"Oops. The Earth is a sphere, not flat."
"Well, Earth is the center of the universe."
"Oops. We travel around the sun."
"Oh. Well, The sun is the center of the universe."
"Uh, see those stars in the night sky? They are suns... and ours is a pretty ordinary one."
"Well we are in a big thing called the Milky way; the only one."
"Wrong again. Lots of those things that look like stars are galaxies containing billions of stars each."
"Well, it all expanded from one single thing at a certain time in the past."
"Ummmm..."
I know a lot of people have problems with infinity, but if the universe is infinite in size (something I "prefer" because I find it easier to imagine) then the universe could have been expanding forever but always been infinitely big... just becoming a larger infinity. :) (That pop you just heard was your mind breaking.) Or it could have "bounced" long before reaching the zero point, having previously collapsed to some density limit.
And yes, I know there is other observational data like the makeup of galaxies as we peer back in time with our telescopes, but none of that says conclusively that there was a big bang. It could be that there was a local catastrophic event, or that galactic births follow cycles. We don't really know.
I don't count the cosmic microwave background radiation as "proof" of the big bang. I remember when I was a kid reading science journals the microwave background was at one point considered evidence against a big bang.
My point is not to say what did happen, but to point out that believing there was a big bang seems a mistake. Such belief is based on inferences that always looked to me less than convincing at best, and "magical" thinking at worst. It seems to me that it jumps to conclusions, when there may be other ways of looking at the data.
Just to reinforce my point: I'm not saying a big bang did not happen. I'm just saying I find it hard to swallow, and so long as I can come up with alternatives I'm not going to believe any single explanation... even ones that feel right to me. I reserve judgment. I certainly won't believe something just because others do.