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The case against asymptotic freedom
In this talk I give an overview of the work done during the last 15 years in
collaboration with the late Adrian Patrascioiu. In this work we accumulated
evidence against the commonly accepted view that theories with nonabelian
symmetry -- either two dimensional nonlinear models or four
dimensional Yang-Mills theories -- have the property of asymptotic freedom (AF)
usually ascribed to them.Comment: 18 pages, 2 figure
E. Cartan's attempt at bridge-building between Einstein and the Cosserats -- or how translational curvature became to be known as {\em torsion}
\'Elie Cartan's "g\'en\'eralisation de la notion de courbure" (1922) arose
from a creative evaluation of the geometrical structures underlying both,
Einstein's theory of gravity and the Cosserat brothers generalized theory of
elasticity. In both theories groups operating in the infinitesimal played a
crucial role. To judge from his publications in 1922--24, Cartan developed his
concept of generalized spaces with the dual context of general relativity and
non-standard elasticity in mind. In this context it seemed natural to express
the translational curvature of his new spaces by a rotational quantity (via a
kind of Grassmann dualization). So Cartan called his translational curvature
"torsion" and coupled it to a hypothetical rotational momentum of matter
several years before spin was encountered in quantum mechanics.Comment: 36 p
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