If I could alter my brain and adapt to one particular profession, high on my list would be a cosmologist. It’s just such a cool time to be alive, in terms of space probes confirming or disproving theories, and the universe throwing curve balls at every step. Unfortunately the maths is way beyond my capability1, but I’ve been roughly following the field for years and years. I find that it’s important to actually keep up with developments, as things are rapidly changing. For example, the last couple of years have seen large changes in the understanding of dark matter and dark energy.
Dark matter is matter that only indicates its existence through its gravitational effect on other matter – it’s not detectable in any other way. But another interpretation of this is that our understanding of gravity is wrong. This was still an option when I took an Open University cosmology course a few years back, but recent observations pretty much killed that theory.
Dark energy is the mysterious force causing the acceleration of the universe to increase, and analyses of the movements of massive-scale galaxy clusters have shown they move exactly as predicted by current theories of gravity – if dark energy were also a flaw in our understanding, it’d be detectable at those levels2.
We’re figuring this all out right now. That is cool. The best I can do is stand at the sidelines and catch what I can, which is why I like Astronomy Cast so much – I can follow recent developments without great amounts of effort on my part, which suits me just fine 🙂 Today’s episode caught me out – I thought I roughly understood the concept of the shape of the universe, but their recent episode on the topic caused many WTF moments. I’m a little out of date. It turns out that the WMAP probe has found the universe is likely to be totally flat – no matter how big a triangle you draw in space, the angles will always add up to 180 – but, this requires fine-tuning to an insane degree, as a difference of 1 in 447 sextillion in densities during the big bang would have created a non-flat universe. So there’s got to be either a) some new physics out there or b) a bajillion big bangs, and we have to be in one of them. Wow!
Wish I could be a cosmologist. Can’t, though, but I’ll try to keep up – I’d hate to be alive and miss it all.