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Bwanika,
The theory of evolution is objectively
correct. If we take the weak anthropic principle, which asserts that the laws of
physics must be of such a nature to enable us to evolve and exist, it follows
then that every theory of the origin of the universe, including the
Hartle-Hawking theory, cannot violate the weak anthropic principle therefore it
cannot contradict Darwin. Of course if evolution is a mere
social construction then of course anything goes but thankfully science is
not a social construction!
Also you should be careful and not confuse
Hawking's work on black holes with his work on the origin of the universe. It
seems to me that you are thinking of the Hawking-Penrose singularity theorems?
These assert that, according to Einstein's theory of general relativity, the end
point of gravitational collapse of a star of mass greater than 3 suns must end
in a black hole and a space-time singularity. Conversely they also demonstrate
that the universe must have began with a space-time singularity, which can be
conceived as gravitational collapse of a star in reverse. I think this what you
are alluding to in your post.
Now what the singularity theorems
ultimately suggest, and both Penrose and Hawking agree, is that Einstein's
theory of general relativity is incomplete for physics collapses at a space-time
singularity. In other words General Relativity cannot tell us what is the end
point of the gravitational collapse of a star nor the origin of the universe. To
do this we need a quantum theory of gravity, a combination of general relativity
with quantum mechanics. This is where agreement ends. So Penrose is working on
his Twistor Theory approach to quantum gravity, Hawking on Euclidean quantum
gravity, Lee Smolin and others at Penn State on loop quantum gravity and its
variants and just about everybody else on string/M theory. Without a quantum
theory of gravity there exists no ultimate theory on the gravitational collapse
of a star or the origin of the universe. Evolution theory by contrast is
objectively correct.
To explore these issues further if you
haven't already checked them out check out these web sites which have
plenty of authoritative info on these matters.
2.) The Institute for Theoretical Physics
at Santa Barbara public lecture web sites (there's lectures here by Hartle on
gravity and Ed Witten, the god of string theory on space-time and M theory) at
www.itp.ucsb.edu/activities/public/
3.) For the accelerating expansion of the
universe and infinite/finite debate see a really good lecture online by Michael
Turner, a leading theorist on the issue, at the Fermi National Lab at www.fnal.gov/
I think you will find these sites
informative and fun to check out! Also I apologise for not picking up earlier
that you were referring to Hawking's singularity theorems in your original
post.
Regards,
Marko.
----- Original Message -----
Sent: Friday, March 22, 2002 8:21
PM
Subject: RE: BHA: Re: Critical Realism
for Natural Sciences
Marko!
Thank for yours!
I do largely agree that
Hawking Black holes might not be a theory in it's entirety. Shouldn't we ask
then, if Hawking black holes, matter and anti-matter are the very essence of
nature? I'll suppose so, if his explanation of the origins of the universe is
based on super nova's characteristic changes in gravitation and body mass. You
believed I suppose, there was no evidence to this? But there is, the only
hurdle is explaining what it is that matter and anti-matter is, after atomist
Democritus fall.
The string theory is going full circle to Aristotle's
original observations. Now, just imagine the catalytic nature of light in
plant food making processes. Wouldn't you like to ask what is light? A
wave or a particle ? At least if it is a particle, Hawking has a theory vis -
a -vis the virtual particles and anti-particles is spot on from a chemist
point of view.
The problem Hawking and other faces is
gravitation and mass, re-light particle definition and its physical
properties. At least I only see color spectrum in exploding stars. On
the one hand, it will be interesting to know from Hawking himself if he
believes particles in the absence of anti-particles disintegrate i.e. to
generate gravitation entropy or that this happens only where there
anti-particles.
But then, I imagined I sitting in a speeding car
at 70 km/hr with my light weight body. Indeed at that speed, I will become a
heavy weight. But why do light particles do not hit the earth for example, in
a thunderous bust but rather end up making the earth and universe beautiful as
it is?
Marko as of the above this is what you wrote;
>But
notice how this has flied right in the face of the recent
discovery that the >Universe is speeding up in its expansion, which
could very well be the result of the >vacuum or zero point
energy what is called dark energy, meaning that the
>cosmological constant is non zero (which has string theorists increasingly
in a spin) >meaning that the universe will not contract, it
will expand forever (this discussion >is to ignore quintessence which may
imply that the universes speed up is >temporary).
In
this regard, one might wonder where the particle from the sun ends on hitting
plant leaf for example or the earth surface? Reflected or travels on? This is
rather a curious and dubious question too, for it will presuppose the infinite
chemical process i.e. infinite nature of expansion of the universe or
evolution for that matter!
Do you still believe the universe as per
Hawking argument is finite?
Last night to make sure that I had
understood you, I looked at the clear sky and I did not see a lot of stars but
rather a large dark patches in space with twinkling stars in between large and
at time very large spaces!
bwanika.
Marko Beljac <beljac@xxxxxxxxxxxxxxxx>
wrote:
>Bwanika,
>
>I am somewhat puzzled by the
argument presented here. As far as I am aware Hawking does indeed have a
theory in regards to the origin and evolution of the Universe. In a joint
paper with James Hartle in the 1980's entitled "wave function of the universe"
Hawking and Hartle developed what is called the no boundary condition theory.
Now this is an application of his Euclidean quantum gravity to the question of
the origin of the Universe. Notice that this does not have anything to do with
black holes. Also it must be stressed that the Hartle-Hawking theory is
quite speculative being an example of the genre of quantum cosmology. On the
other hand Hawking's work on gravitational entropy, i.e. exploding black
holes, must be a part of any quantum theory of gravity. For instance Juan
Maladcena, a string theorist, has derived Hawking's gravitational entropy
using string theory. So by no means is Hawking's theory on the origin of the
universe an established theory. Indeed for years Hawking was arguing that the
Universe is finite, that is that it will expand and eventually contract. But
notice how this has flied right in the face of the recent discovery that the
Universe is speeding up in its expansion, which could very well be the result
of the vacuum or zero point energy what is called dark energy, meaning that
the cosmological constant is non zero (which has string theorists increasingly
in a spin) meaning that the universe will not contract, it will expand forever
(this discussion is to ignore quintessence which may imply that the universes
speed up is temporary). There is an interesting exchange between Stephen
Hawking and Roger Penrose in The Nature of Space and Time where Hawking
emphatically states (before the recent discovery) he wants the universe to be
finite because of the no boundary proposal whereas Penrose argues, given his
approach to quantum gravity i.e. twistor theory, he wants the universe to be
infinite and to keep on expanding forever! So Hawking could very well be
wrong!
>
>Evolution on the other hand is a tried and tested
theory. It is objectively correct., although I am aware that in saying this I
am inviting trouble! At any rate there is no connection between cosmology and
evolutionary theory. If Hawking is wrong the evolutionary biologist would be
quite right in exclaiming, so what!
>
> The second part of your
thesis is very interesting with serious implications. I would be very
interested in reading a further elaboration of it. Also in regards to black
holes and evolution theory, does this steam from a reading of Lee
Smolin?
>
>Marko.
--
____________
Bwanika
url:
http://www.uganda.co.ug
e-mail: dbbwanika@xxxxxxxxxxxx
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