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arXiv · hep-th/9712019

The C_2 heat-kernel coefficient in the presence of boundary discontinuities

J. S. Apps·J. S. Dowker
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Abstract

We consider the heat-kernel on a manifold whose boundary is piecewise smooth. The set of independent geometrical quantities required to construct an expression for the contribution of the boundary discontinuities to the C_{2} heat-kernel coefficient is derived in the case of a scalar field with Dirichlet and Robin boundary conditions. The coefficient is then determined using conformal symmetry and evaluation on some specific manifolds. For the Robin case a perturbation technique is also developed and employed. The contributions to the smeared heat-kernel coefficient and cocycle function are calculated. Some incomplete results for spinor fields with mixed conditions are also presented.

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J. S. Apps, J. S. Dowker. 1997-12-02. The C_2 heat-kernel coefficient in the presence of boundary discontinuities. https://doi.org/10.1088/0264-9381%2F15%2F5%2F005

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