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So, um, it’s *possible* that some parts of the Universe are expanding faster than others.
If that’s true, then some *very* basic assumptions we make about how the Universe behaves need to be looked at *very* carefully. https://www.syfy.com/syfywire/are-some-parts-of-the-universe-expanding-faster-than-others-maaaaaaybe
If that’s true, then some *very* basic assumptions we make about how the Universe behaves need to be looked at *very* carefully. https://www.syfy.com/syfywire/are-some-parts-of-the-universe-expanding-faster-than-others-maaaaaaybe
2/ To be clear, this is not an OH NOES EVERYTHING WE KNOW ABOUT COSMOLOGY AND SCIENCE AND ASTRONOMY IS WRONG!1!! kind of moment. Not that this will slow conspiracy theorists and anti-science chuckleheads.
But something *is* amiss. The question is, is it with us or the Universe?
But something *is* amiss. The question is, is it with us or the Universe?
3/ Looking at superhot gas in clusters of galaxies as a way to measure cosmic expansion, astronomers found that the Universe seems to be moving away from us faster in one direction on the sky than another. That’s… unexpected.
4/ It’s *possible* their observations are off somehow. They looked into that pretty carefully and found some stuff that could affect their results. Like, maybe clumpy gas around our own galaxy changing what things look like in some directions vs. others. They can’t rule it out.
5/ But they rate that as unlikely. I was wondering if it might be something local to us. Maybe our own galaxy is moving in a funny way, maybe due to too much matter in one direction in the sky pulling on us versus another. We’d see stuff moving away from us faster *behind* us.
6/ But then you’d see the expansion being at a min ahead of us and at a max behind us, 180° apart on the sky. The map the astronomers generate shows the min/max expansion change about 90° apart. So it’s not local.
7/ If it’s not the observations, and it’s not us, then maybe it *is* the Universe? The thing is, one of the most basic assumptions we have is that the Universe is isotropic, the same in every direction. This would mean that assumption is incorrect. Yikes.
8/ The thing is we have TONS of evidence the Universe IS isotropic on very large scales (see Background, Cosmic Microwave or click the video below). So maybe the Universe is lumpy on smaller scales. By that I mean, oh, over a few billion light years.
9/ This does NOT the mean the Universe isn’t expanding or accelerating or the Big Bang didn’t happen or whatever pet theory you might have. If this new stuff is true, it just means that *some* aspects of what we thought we understood we need to rethink.
10/ This is the first decent evidence I’ve seen that the expansion isn’t uniform (there have been hints before). It’s the place we start, not the place we finish. We’ll need a lot more evidence before we dump our basic assumptions. That’s how science works.
11/11 So stay tuned. I’m sure there’ll be interest in this, whether it’s to more closely examine these results or to get more observations to see if they hold up. We’ll find out if we were right all along, or if we have to rethink stuff.
Either way, fun! https://www.syfy.com/syfywire/are-some-parts-of-the-universe-expanding-faster-than-others-maaaaaaybe
Either way, fun! https://www.syfy.com/syfywire/are-some-parts-of-the-universe-expanding-faster-than-others-maaaaaaybe
