Re: BHA: Re: Critical Realism for Natural Sciences

[Mervyn Hartwig <mh@xxxxxxxxxxxxxxxxxxx>]

Hi Marko (and Bwanika)

Many thanks for this, especially the details of the websites.

Pardon my ignorance, but who espouses the weak anthropic principle? Is
it widely accepted within physics and other sciences? I ask in
particular because it has some resemblance to the intrinsic cosmic
structure of possibility the later Bhaskar refers to as 'God'.

Mervyn


Marko Beljac <beljac@xxxxxxxxxxxxxxxx> writes
>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.
>1.) The official superstring theory web site:  www.superstringtheory.com
>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 -----
>  From: dbbwanika@xxxxxxxxxxxx
>  To: bhaskar@xxxxxxxxxxxxxxxxxxxxxxxxxx
>  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.
>
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>  ____________
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>  Bwanika
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>  url: http://www.uganda.co.ug
>  e-mail: dbbwanika@xxxxxxxxxxxx
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--
Mervyn Hartwig
Editor, Journal of Critical Realism (incorporating 'Alethia')
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