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If I Only Had A Brane!

Tasneem Zehra Husain
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Abstract

This thesis starts with a review of BPS M-branes and their supergravity solutions. These solutions can be obtained in various ways. We describe the harmonic function rule and the Fayyazuddin-Smith metric ansatz in detail, illustrating both methods by examples of M-branes wrapping holomorphic curves. Another, simpler way, is to use calibrations. In order for a wrapped brane to be BPS, the cycle it wraps must be calibrated; given the relevant calibration, there exists a procedure which yields the supergravity solution almost immediately. In the past, this method was applied only to Kahler calibrations, as these were the only ones known to exist in backgrounds with non-trivial flux. We extend this method to a wider domain, using a constraint to classify possible calibrations. A rule is given which can generate the required constraint for any given M-brane wrapped on a holomorphic cycle. Ways in which this constraint can be satisfied are also discussed.

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Tasneem Zehra Husain. 2003-04-16. If I Only Had A Brane!. https://arxiv.org/abs/hep-th/0304143

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