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View Full Version : Star Formation - Continued......



hrherle
2004-Nov-23, 02:42 AM
Well it is after quite a long time i am writing a new topic. With gerat difficiculty ( :oops: :cry: ) I finally managed to understand "The Breif History Of Time" of Stephen Hawkings. I have got few doubts namely,

1) Supposs a Star names * generally are formed from the Interstellar mass lying around dead stars and they further radiate energy thus converting some mass into energy. At the end of their life cycle, the Star * emit some of the mass back into the interstellar medium. This emitted mass will be quite lesser than the ones which were avaliable when Star * was formed. So in the course of time, a) future stars will be lesser massive in comparision to their ancestors. b) unless all the mass is converted to energy, the process of star formation and death continues
Am i correct ? In the future, when all the mass is converted to energy, what could be the next step? 8-[

2) During the star formation, density fluctuation will lead to attraction of one particle to another which will continue in attration of more particles. This will end up in rotation of the group. How is the centrifugal force balanced by the gravity? :-?

3) It seems that universe may collapse in the future when the energy is fully utilised and gravity will take over. Now my doubt is compression will lead to increase in temperature, which may yeild on further expansion rather than paving way for big crunch. :-?

I suppose this is enough for me.

Evan
2004-Nov-23, 04:09 AM
If the universe is either open or flat (bets are on flat right now) and the proton does in fact decay (jury out) then eventually all matter may end up decaying regardless of composition. A proton has been shown by experiment to have a half life which is bounded to no less than 10^33 years. If the protons in a nucleus decay then a free neutron has a half life of 10.3 minutes. It is possible that neutrinos decay as well. Many, many, many years in the future the universe may end up as a very cold completely dark space with no matter and a weak flux of possible very long wavelength photons. Boring.

Brady Yoon
2004-Nov-24, 04:39 AM
So if protons decayed while humans were still alive, we'd be toast? (silly question since that's not for a loooong time :x :lol: