jrl@harpo.UUCP (jrl) (04/03/84)
Here is an interesting question posed by a friend. It is believed
that we live in an expanding universe that was created from an very small
very dense and very hot 'point' that let go around 20 billion years ago.
There are two outcomes of this. One being that this event was a one time
thing and the universe is open. That is that it will keep expanding until
entropy sets in and the stars die out and that is the end of it. The other
theory is that the universe is an oscillating one. That is it expands, and
after some time it contracts again into that 'point' and the big bang starts
over again with a new universe with new phyisical laws and constants.
I tend to subscribe to the latter theory since the contraction of
the universe into a primordal 'point' that goes off again makes some
sense. If the universe is a one time occurance, then one can say that
perhaps the first line in the bible explains it all .... In the beginning
there was light ! ......
Now the question: When the universe was the size of a softball (i.e.
at T = 1 x 10 E -39 second and the temprature was 1 x 10 E +35 degrees
kelvin) WHAT WAS THE FIREBALL EXPANDING INTO ????? and what lies beyond
the 20 billion light-year barrier.
An interesting article appeared in Scientific American about the
creation and state of the universe. One interesting thing is that perhaps
we exist in more than four dimensions, They said that a universe with
seven dimensions works out well in theory. And another interesting point
that was made is perhaps the distinction between past, present and future
becomes 'blurred' at the Plank level of dimensions ( 1 x 10 E -33 cm).
Too bad I can not understand the math used to postulate these interesting
theories
harpo!jrlgodin@akov01.DEC (04/05/84)
There has been much discussion on whether the universe is "open" or "closed". The thought of a "open" universe is unappealing to us because we like to think that "something" will go on forever. If the "Big Bang" was a one time occurance and it we accept the Law of Entropy, the future of the universe is rather bleak. The notion of the "close" universe is more appealing because of the cyclic nature of the universe in that theory. We may perish but at least the universe will continue on. One other theory states that we exist in a universe within a universe. That our universe may be a atom in another universe and that the creation and destruction of our world occurs in a "split second" of the other world. After all the most basic thing to us, time, is only relative. We "time" the univrese by how many times the Earth goes around the Sun. Just think if our year to an outside observer (God?) takes by that observer's watch a tenth of a second, then the whole life of the universe has taken a couple of minutes. Film at Eleven.
Lynn.es@Xerox.ARPA (04/09/84)
Although we haven't found enough matter to gravitationally stop the expanding universe in the distant future, there are a couple of indications that there may be hidden stuff that will do the job. First, some galaxy rotational studies show that what we see in galaxies is surrounded by a lot more matter that we don't see. Second is the recent measurements that seem to indicate that the Neutrino may have a small, but non-zero, rest mass. This particle should inhabit the universe in incredible numbers according to current theories of nuclear fusion, and might, even with a tiny mass, add up to more mass than the matter we are used to. Now for the real question you posed (WHAT WAS THE FIREBALL EXPANDING INTO ?). By general relativity, we consider space itself curved by gravity. If the universe has enough mass to eventually collapse, then space actually curves around on itself. There is no outside (not in three dimensions), you just come back on yourself eventually. If the universe is not gravitationally closed, then it's even harder to explain. I guess it's something less than empty space. Incidentally, we don't know that the big bang started as a point. We just don't know of any limit to the density of matter, so when we extrapolate the expansion backwards, it reaches a point. "what lies beyond the 20 billion light-year barrier"? Unless we can find some means that transmits information faster than light, we will never know what is beyond the barrier, that is, beyond x light years, where x is the age of the universe. /Don Lynn
ward@hao.UUCP (Mike Ward) (04/09/84)
[]
The notion that the universe is "open" depends on the present estimate
of the mass contained in the universe. But that estimate seems to
be increasing on the same curve as computing power (that is: LOTS
every few years - how's that for precision). I put my money on the
closed universe, though I have no bias, one way or 'tother.
--
Michael Ward, NCAR/SCD
UUCP: {hplabs,nbires,brl-bmd,seismo,menlo70}!hao!ward
BELL: 303-497-1252
USPS: POB 3000, Boulder, CO 80307jgb@linus.UUCP (Jonathan G. Bressel) (04/20/84)
> Here is an interesting question posed by a friend. It is believed >that we live in an expanding universe that was created from an very small >very dense and very hot 'point' that let go around 20 billion years ago. >There are two outcomes of this. One being that this event was a one time >thing and the universe is open. That is that it will keep expanding until >entropy sets in and the stars die out and that is the end of it. The other >theory is that the universe is an oscillating one. That is it expands, and >after some time it contracts again into that 'point' and the big bang starts >over again with a new universe with new phyisical laws and constants. > I tend to subscribe to the latter theory since the contraction of >the universe into a primordal 'point' that goes off again makes some >sense. If the universe is a one time occurance, then one can say that >perhaps the first line in the bible explains it all .... In the beginning >there was light ! ...... > harpo!jrl harpo!jrl is entitled to this opinion, but I can't help noticing the absurdity of this reasoning. Since we haven't sufficient information about the density of the universe, the only valid, scientific statement we can make is that we don't yet know which theory gives a more accurate description of the universe. A scientist doesn't "subscribe" to a theory because he likes its philosophical consequences. In this case harpo!jrl seems to favor the perpetual contraction theory merely because the alternative theory resembles too much the account given in the bible. As a point of information, the first line of the Bible reads: "In the beginning God created the heavens and the earth." -- Jonathan G. Bressel ARPA: linus!jgb@mitre-bedford UUCP: ...{decvax,utzoo,philabs,security,allegra,genrad}!linus!jgb