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تسجيل مستخدم جديدPregeometry and spontaneous time-space asymmetry
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C. Wetterich
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In pregeometry a metric arises as a composite object at large distances. For short distances we investigate a Yang-Mills theory with fermions and vector fields. The particular representation of the vector fields permits to formulate diffeomorphism invariant kinetic terms. Geometry and general relativity emerge at large distances by spontaneous symmetry breaking inducing masses for the gauge bosons. We propose here a model of pregeometry for which the difference between time and space, as reflected by the signature of the metric, arises from spontaneous symmetry breaking of the local SO(4,,$mathbb{C}$)-gauge symmetry. For a euclidean metric all fields have a standard propagator at high momenta. Analytic continuation to a Minkowski-metric is achieved by a change of field values. We conjecture that a quantum effective action of this type is consistent with unitarity and well behaved in the short distance limit.
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