Polchinski: 2006, the Year in Strings

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Polchinski: "2006, the Year in Strings"

Joseph Polchinski gave a well attended plenary lecture titled:

Polchinski: "2006, the Year in Strings"
http://www.phys.hawaii.edu/indico/contributionDisplay.py?contribId=746&sessionId=25&confId=3

The above link gives the slides. I found several parts of it interesting. First, I thought that getting string theory as the limit of a mesh of Feynman diagrams was cool. And he talked quite a bit about 5-D theories. This is personally interesting because I use 5-dimensional space-time in my internal papers, with the 5th dimension being related to proper time (this is known as "Euclidean relativity", and by many other names and I am not the only heretic involved with the travesty).

And then he talked about the landscape and the anthropic principle. He said that the inflation scale is smaller than the Planck scale by at least a factor of 10^4, and this was of great interest to me. I've toyed around with trying to explain inflation by having preons that travel faster than c and have Planck scale masses. So one wonders how one would make the calculation and perhaps predict the exact value of the inflation scale from the Planck mass and Clifford algebra.

There were two questions. The first was a request to comment on Susskind's alleged suggestion that we could be at the end of physics in that we are at the "end of the reductionist paradigm". The speaker wisely avoided commenting on Susskind, but said he himself does not have a paradigm, and that serious cosmologists have been worrying about this for >30 years, that is, what is it that allows life.

The second question was about the abilitiy of a large extra dimension allowing solving of the hierarchy problem. He speculated that maybe someone in the audience knew the answer to this but he didn't call on me by name (LOL), and mentioned the embedding of 5-D theories in 10-D.

It was a nice lecture.

Carl
 

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Thanks for the reference to Polchinski: "2006, the Year in Strings".

Speculative comments [my interpretive perspective]

1 - On the 2nd slide of Gauge / String Duality
"1974: t'Hooft ... in the strong-coupling limit Feynman graphs become dense"
may be equivalent to
knot theory becoming dense as chaos theory of attractors?

2 - slide of Running Couplings
“... once the coupling drops below ~4[Pi] the space time curvature gets large ...”
may be equivalent to
2 periods or perhaps even spin-2?

3 - slide of Confinement Forces Chiral Symmetry Breaking
“Right and left branes pair up ...”
may instead be equivalent to
right and left branes fold together only apparently breaking symmetry
possible example
a square might be decomposed into 4 equilateral triangles - if bent along the triangles, such symmetry may be viewed, but if not bent, remaining planar, these triangles are obscured with only the square viewed
likewise a six sided cube may be decomposed into 24 equilateral triangles which might be bent into something resembling a torus by folding the top and bottom toward the interior while the front-back and left-right surfaces are folded outwards

4 - slide on KS throats
“... warped deformed conifold ...”
may be equivalent to Figure [10] in
2 Complex Functions as Transformations
II Polynomials
3 Cassinian Curves
Visual Complex Analysis [1997 to 2002] by Tristan Needham [Math, U-SF]
http://www.usfca.edu/vca/

This Figure [10] appears to unify
a - stacked ellipse and cones [2 pictured “as a geographical contour map of the modular surface of the quadratic“]
b - tori ["spiric sections of Perseus"]
c - knots [Bernoulli lemniscate or fugure-8]
d - saddle points [inferred from figures - important in game theory]
 

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