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Model the expansion of the universe assuming a foam like structure and a non-zero cosmological constant at different values. Then model the path of light rays t
by richardjordan 14y ago
Model the expansion of the universe assuming a foam like structure and a non-zero cosmological constant at different values. Then model the path of light rays traveling large distances over long periods of time. The patterns of hydrogen absorption lines should be pretty distinctive and could be used to test various cosmological possibilities.
This was my 1995 final year Physics project with inadequate hardware and poor language options.
Of course back then the assumptions were considered a bit radical but now much more accepted as reflecting something approaching reality.
I think it would be an interesting project to do it again with modern tools and some real computing horsepower.
- madaxe 14y agoGuessing you saw the article on the lack of quantisation jitter on quasar light then, then? :)
- richardjordan 14y agoRight. Which is interesting on a whole host if levels. Though, this is more of a macro experiment. You're really measuring distribution of "walls" and "filaments" of matter in the universe by measuring the hydrogen absorption lines ... As the lines get shifted and new ones occur you get a sort of barcode pattern, each possibility distinctive of certain histories of expansion and build up of structure. There should be clear signatures of, for example inflection points where an expansion switches to contraction or a slowing expansion flips to an accelerating one.
- madaxe 14y agoYou may find http://www.astro.auth.gr/~tsagas/Publications/Journals/MNRAS/MNRAS6.pdf http://www.astro.auth.gr/~tsagas/Publications/Journals/MNRAS... interesting if you haven't seen it already, suggesting FLRW could still be consistent with observations. But yeah, totally agree that this would be a neat simulation to run!
- richardjordan 14y agoThat is a interesting paper. I'm gonna read it later. The dipole observations related to galactic spin was a fascinating discovery a while back. More evidence for an "axis" presents some interesting cosmological possibilities. Thanks for this evenings reading assignment :-)
- madaxe 14y agoNo worries. Nights are best spent trawling through papers, gently blowing one's mind. Always a pleasure finding someone else passionate about cosmology!
- richardjordan 14y agoEverything else is just stamp collecting ;-)