h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

Minor criticism (no offence intended!): this article seems to be a little out of date as it does not even *mention* the existence of dark energy. For those who don't know, this is some form of energy which repels the galaxies and acts against the gravitational force which would otherwise be slowing them down, and would thus prevent any recollapse of the universe.

On another note, I think they've found that omega=1 anyway; partly borne out by the WMAP evidence for inflation I think (the theory of inflation predicts that omega=1) and that the contribution from dark energy must be about 70% (dark matter contributes about 30%, baryonic or 'normal' matter about 4%-I know it doesn't add up, these are only rough figures!!!)

If anyone wants to add or correctanything I've said here feel free-I'm only a first-year undergrad you know!!!

Mind you, if you believe the BBC website, these are unresolved questions...

I expect you know more about it than I do if you're currently studying the subject. Theories seem to change every time you turn your back, which makes it very exciting, but information becomes 'stale' quickly.

I'm suspicious of Omega = 1. It's just too convenient, somehow; like we've overlooked something obvious or we've assumed our conclusion or some such.

Don't mind me, I'm just nattering on. It's time to go back and revisit this (maybe material for another article?)...

Studying the subject? Well, sort of, but what we did this year was only quite brief, part of a lecture course called 'Cosmic History' in the module 'Introduction to Astronomy' which is definitely only an introduction, although it explored the basic ideas.

As for Omega = 1, all I know is that it was one of the consequences of inflation theory, and that the data from the WMAP satellite seemed to fit with the predictions for inflation, or suchlike. I'll have to look at the subject again, I'm not really sure that much about inflation or exactly what the WMAP satellite proved, and as for dark energy... I really only looked at this in detail when the results first came out, and a little bit for a piece of A-level (qualification for 16-18 year olds in England in case you're unsure) coursework, and of course in the lectures...

(and you thought *you* were nattering? I'm afraid I go on longer-not necesserily a good thig, of course...)

Studying the subject? Well, sort of, but what we did this year was only quite brief, part of a lecture course called 'Cosmic History' in the module 'Introduction to Astronomy' which is definitely only an introduction, although it explored the basic ideas.

As for Omega = 1, all I know is that it was one of the consequences of inflation theory, and that the data from the WMAP satellite seemed to fit with the predictions for inflation, or suchlike. I'll have to look at the subject again, I'm not really sure that much about inflation or exactly what the WMAP satellite proved, and as for dark energy... I really only looked at this in detail when the results first came out, and a little bit for a piece of A-level (qualification for 16-18 year olds in England in case you're unsure) coursework, and of course in the lectures...

(and you thought *you* were nattering? I'm afraid I go on longer-not necesserily a good thing, of course...)

Oops! Posted same thing in twice-one of thm had a spelling mistake so I quicky tried to correct it-now know the error of my ways!