and one more thing, john doe

[John Doe]

Thank you very much Blake, for finding the source
which answers the issue at hand far better than I did
- you rock!

--- Blake Stacey <blake.stacey at ens-lyon.fr> wrote:

> Quoting Geocoda at aol.com:
> 
> >
> > Sheldon Glashow actually said:
> >
> > But oddly there has been a new development, in
> which a new class of
> > physicists is doing physics, undeniably physics,
> but physics of a 
> > sort that does not
> > relate to anything experimental. This new class is
> interested in 
> > experiment from
> > a cultural but not a scientific point of view,
> because they have focused on
> > questions that experiment cannot address.
> >
> > So, not to nitpick and qualify, Johnny, but you've
> misunderstood a couple of
> > key points.
> >
> > 1) It's physics, for sure
> > 2) It is not temporarily, but permanently outside
> the experimental method
> >
> 
> <snip>
> 
>  From Barton Zwiebach's **A First Course in String
> Theory** (2004), p. 8:
> 
> "It should be said at the outset that, as of yet,
> there has been no 
> experimental
> verification of string theory.  In order to have
> experimental verification one
> needs a sharp prediction.  It has been difficult to
> obtain such a 
> prediction. String theory is still at an early stage
> of development, 
> and it is not so easy
> to make predictions with a theory that is not well
> understood.  Still, some
> interesting possibilities have emerged."
> 
> Two pages later:
> 
> "As a theory of quantum gravity, string theory will
> be needed to study 
> cosmology
> of the Very Early Universe.  The deepest mysteries
> of the universe seem to lie
> hidden in a regime where classical general
> relativity breaks down.  String
> theory should allow us to peer into this unknown
> realm.  Some day, we may be
> able to understand the nature of the Big Bang, and
> know whether there is a
> pre-Big Bang cosmology.
> 
> "Most likely, answering such questions will require
> a mastery of string theory
> that goes beyond our present abilities.  String
> theory is in fact an 
> unfinished
> theory.  Much has been learned about it, but in
> reality we have no complete
> formulation of the theory.  A comparison with
> Einstein's theory is
> illuminating.  Einstein's equations for general
> relativity are elegant and
> geometrical.  They embody the conceptual foundation
> of the theory and feel
> completely up to the task of describing gravitation.
>  No similar equations are
> known for string theory, and the conceptual
> foundation of the theory remains
> largely unknown.  String theory is an exciting
> research area because the
> central ideas remain to be found."
> 
> And the last paragraph of the first chapter:
> 
> "Describing nature and formulating the theory --
> those are the present-day
> challenges of string theory.  If surmounted, we will
> have a theory of all
> interactions, allowing us to understand the fate of
> spacetime and the 
> mysteries
> of a quantum mechanical universe.  With such high
> stakes, physicists 
> are likely
> to investigate string theory until definite answers
> are found."
> 
> To sum it up in one word, string theory is
> "protoscience".  **Given** future
> advances in our understanding, it **will be** within
> the realm of experimental
> verification or falsification.  At present, it might
> callously be dismissed as
> a mathematical game, but the "game" has in fact
> already had a payoff.  The
> study of Dirichlet branes, a topic which came into
> vogue in the mid-1990s, has
> led to new ways of formulating, exploring and
> teaching gauge theories, which
> were developed half a century ago and were thought
> to be a different subject
> altogether.  Yang-Mills gauge theories are useful
> tools, and we **already
> have** experimental proof that some subatomic
> particles obey them.  Therefore,
> in an indirect way, the "mathematical game" of
> string theory has already had a
> useful result, one which will remain valid whether
> or not strings themselves
> stay in favor.  Supersymmetry, another out-there
> concept from high-energy
> physics, began with people trying to explore string
> theories back in 
> the 1970s.
> It has since become a field of study on its own, and
> (thanks to Ed Witten and
> others) beginning around twenty years ago it has
> found applications in quantum
> mechanics, the study of diffusion, and other
> subjects, all of which have
> "everyday" applications.  Supersymmetry, the child
> of string theory, is all
> growed up and has children of its own:  this third
> generation is **already**
> proving useful, and will continue to do so, even if
> its "grandparent" fizzles
> into obscurity.
> 
> In the sixteenth century, one could have dismissed
> the Copernican model of the
> Solar System as a mathematical game, a technique for
> calculation that had no
> real bearing on reality.  Copernicus's editor took
> this very stance in the
> preface to Copernicus's 1543 book which laid the
> model out.  In fact, the
> predictions made of the planets' motions were
> sometimes **worse** with the
> Copernican model than with the Ptolemaic model which
> preceded it.  All the
> charges brought against string theory now could be
> brought against the
> Copernican solar system in 1600, and probably even
> more so, since until his
> work testing the model led Kepler almost up to
> inventing calculus, no new math
> came out of Copernicus.
> 
> The situation changed, of course, when Kepler showed
> that the planets moved in
> ellipses, not circles, superseding Copernicus's
> model and giving it an even
> more elegant mathematical formulation.  In string
> theory, the analagous event
> might be the Second Superstring Revolution back in
> the '90s.  Copernicus was
> vindicated and boosted out of the "protoscience"
> stage when Galileo (and the
> others who followed) made the telescopic
> observations which proved the Earth
> was not the center of the cosmos.  The analagous
> event to this 
> discovery in the
> history of string theory has not happened yet, and
> of course, it might never
> happen at all.
> 
> **All** scientific models pass through a
> protoscience stage, even if 
> this stage
> only lasts an hour.  One might be able to guess a
> new equation in the morning,
> work out its consequences by lunch, and compare them
> to experiment by 
> teatime. The new model could then be proven wrong or
> deemed 
> provisionally acceptable in
> time for dinner.  Naturally, if the math is harder
> or if the essential
> experiments have not been done, this process will
> take longer.
> 
> String theory in seven words:  "Tiny strings.  Hard
> math.  Maybe, big payoff."
> 
> I am unable to find anything in Glashow's statement
> which indicates 
> that string
> theory is "permanently outside the experimental
> method".  He uses the present
> tense, "does not relate", rather than saying "can
> never relate".  He does say
> 
=== message truncated ===



		
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