Conference noted::sf

Is there any relation at all between the number of "forces" and
the number of dimensions in a given model of the universe?  Or
are those totally independent?

Some of the "superstring" theories I have seen postulate either
nine or ten spatial dimensions with one time dimension.  Since
the "extra" spatial dimensions are thought to be hidden within
the elementary particles of our more familiar three dimensional
model, it would seem to me that there might be "extra" forces
operating at that sub-sub-atomic level.  But that's a WAG.

The experiments sound easy enough to repeat, so go for it!

    Roughly speaking, the more forces you have, the more dimensions
    you would need in a multi-dimensional model.  But since there are
    several different models just for a four-force system, each model
    with different numbers of dimensions, the relation between number
    of forces and number of dimensions is not simple or direct.
    
    By the way, to the best of my understanding, the extra spatial
    dimensions are not supposed to be hidden inside elementary particles,
    exactly.  Rather, they are curved into microscopically tiny
    hyperspheres.
    
    Imagine a world of one-dimensional creatures, linelanders.  Now
    suppose that there was a hidden spatial dimension to lineland. 
    Lineland would be like a pipe or soda-straw -- a long thin line
    along one dimension and a tiny circle along the other.  You could
    say that, for every point in the normal space of lineland, there
    is an associated "one-sphere" of miscroscopic dimensions.
    
    Similarly, for every point in three-space, there is (according to
    these theories) a microscopic hypersphere (a 7-sphere or 9-sphere
    or whatever depending on the theory).  The exact shape of the
    hypersphere corresponds to the combination of forces operating at
    that point.  It would be perfectly round only in a place that was
    completely force-free.
    
    Earl Wajenberg

    	The May 1989 issue of NATIONAL GEOGRAPHIC has an article on the 
    Fifth Force, and the latest information on other gravity research.
    
    	Larry
    

    There is a fine discussion of a fifth, anti-gravity force in Steven
    Hawkings, "A Brief History of Time".
    
    One of the debates that has raged in the field of cosmology for the
    last fifty years has been - Do we live in a closed or open Universe -
    That is, is there enough matter in the universe to counteract the
    rate of expansion of the universe as a result of the Big Bang, turn it
    all around, and end up in the Big Crunch? If the answer is no, then
    the universe is open, and will continue expanding for eternity.
    
    The answer is not clear at all. There are black holes postulated which
    contain an unknown amount of matter. There are dark stars and neutron
    stars, collapsars and "dark matter" - nonradiant dust in the
    intergalactic void. As far as anyone can figure, the hubble constant -
    the rate of expansion of the universe - is so close to the critical point
    between collapse and continued expansion that either outcome can be
    persuasively argued.
    
    Hawking makes the point that this is a remarkable coincidence - a
    minescule difference in the rate of expansion in the first minutes
    after the Big Bang from what appears to be the actual value would have
    resolved the question, one way or the other. Out of the infinite values
    possible for the hubble constant, God or nature chose the one value
    which leaves us guessing - right at the break-even point. Hawking
    finds this too coincidental to be true. He postulates that, at such
    high energies as existed immediately following the big bang, when
    matter existed only as undifferentiated quarks, a fifth force which
    causes matter to be mutually repulsive SET THE SPEED of the expansion
    to the hubble constant. As matter immediately cooled and began to form
    nucleons and atoms, the fifth force was inactivated, and thus no longer
    played a role in continuing expansion.  Thus, the hubble constant was
    not arbitrary - it was the outcome of the mass of matter which was
    present directly after the Big Bang.
    
    Deep stuff. I recommend a walk through "A Brief History..." for those
    interested in cosmology, or anyone who thinks they have the universe
    down pat and really wants to be confused.
    
    Max
    

From: [email protected]
Newsgroups: clari.tw.science,clari.tw.space,clari.news.interest
Subject: New unifying theory of Universe proposed
Date: 3 Dec 90 20:28:57 GMT
  
	COLLEGE STATION, Texas (UPI) -- Physicists have worked out a
testable new theory that may be a key step towards linking the
fundamental forces of the Universe in a single, unified model. 

	Preliminary data from recent experiments at the CERN particle
collider in Switzerland appear to support the new theory's
predictions, the scientists said in a news release issued Monday. 

	``It (the theory) seems to encompass all the beautiful things
of the past,'' said Dimitri Nanopoulos of Texas A&M University. ``It
is a supersymmetric theory. It is also a grand unified theory (GUT),
and it is a string theory.'' 

	Nanopoulos said the new model also suggests that a new form of
invisible matter may exist. Dubbed cryptons, from the Greek word for
``hidden,'' they could make up the ``dark matter'' of the Universe.
Physicists use the idea of invisible dark matter to explain the gap
between measurements of the total mass of the Universe and what theory
predicts should be there. 

	A team headed by Nanopoulos and John Ellis of CERN described
the ideas behind their theory in a series of articles published over
the past two months in the journal Physics Letters B. 

	The physicists said the theory explains for the first time in
a single ``grand unification'' model how gravity interacts with the
strong, weak and electromagnetic forces that bind matter together.
Furthermore, the researchers said they have derived a set of rules
that should allow the theory to be tested directly. 

	``We really worked hard, and we finally have a set of rules
that I can use to tell you how to calculate this thing from beginning
to end,'' Nanopoulos said. 

	A number of earlier ``grand unified theories'' have been
proposed, but none have been able to satisfactorily combine all the
forces at once. 

	In an interview with the magazine Science News, Ellis said:
``Even if our particular model turns out not be right, I still feel
that the sort of things that we're learning in our model could be very
useful in unraveling the details of (any better) model.'' 

	The new theory incorporates ideas from the theories of
``superstrings'' and ``supersymmetry'' to go beyond the so-called
standard model of fundamental forces generally accepted by particle
physicists. 

	String theory suggests that matter is made up of vibrating
line-like particles, instead of point-like particles as originally
thought. Cryptons seem to be found in a ``hidden segment'' of the
strings, Nanopoulos said.The idea of supersymmetry allows physicists
to treat particles and radiation the same way in their calculations. 

	The standard model of particle physics describes the relationship 
between ``weak'' force, ``strong'' force and electromagnetism.  However, 
it does not take into account the effect of gravity. 

	The 1989 particle collider experiments confirmed the standard
model, Nanopoulos said. But they also pointed the way toward more
far-sweeping models like that proposed by the Texas-CERN team. 

    Well, someone discovered cryptons.  What's next?  Superman? ;^)

    An interesting convergence: linking "the fifth force" with
    "Superman".
    
    A dozen years back, while in Minneapolis, I went with some friends
    to an Omnimax film at the Science Museum in St. Paul. It was called
    GENESIS and covered the geologic history of the planet. Part of
    the film covered "the four major forces of plate tectonics".
    
    Afterwards, we felt like seeing another film, and chose to go see
    SUPERMAN, which was in its initial release then. During the scene
    where Superman flies into the San Andreas Fault and moves a few
    things around to stop the earthquake, one of my companions said,
    "Aha! The *fifth* major force of plate tectonics!"
    
    Apparently, the people sitting in front of us had seen GENESIS
    recently, because they broke up laughing at Dave's remark.
    
    --- jerry

>Date: 3 Dec 90 20:28:57 GMT
>  
>	COLLEGE STATION, Texas (UPI) -- Physicists have worked out a
>testable new theory that may be a key step towards linking the
>fundamental forces of the Universe in a single, unified model. 

	OK.  Now tell me how to produce or nullify gravity
	with the appropriate electromagnetic apparatus.

	It'll probably turn out to have to be at 30,000,000 degrees C.
	or so, where nuclear particles break down into quarks.