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Speaker_	Aliev, Alikram Nuhbalaoglu
Co-autors	Cihan Saclioglu
Talk_	A. N. Aliev, Self-Dual Fields on the Space of a Kerr-Taub-bolt Instanton
Abstract_	\documentclass[aps,report]{revtex4} \begin{document} \title{\Large \bf Self-Dual Fields on the Space of a Kerr-Taub-bolt Instanton} \author{\large A. N. Aliev} \affiliation{ Feza G\"ursey Institute, P.K. 6 \c Cengelk\" oy, 81220 Istanbul, Turkey} \author{\large Cihan Sa\c{c}l\i o\u{g}lu} \affiliation{Faculty of Engineering and Natural Sciences, Sabanci University, 81474 Tuzla, Istanbul, Turkey} %\pagestyle{empty} \maketitle \noindent Gravitational instantons are usually defined as complete nonsingular solutions of the vacuum Einstein field equations in Euclidean space. One of the fundamental properties of gravitational instantons is that they can harbor self-dual gauge fields that have no effect on the metric. In other words, since the energy-momentum tensor vanishes identically for self-dual gauge fields, solutions of Einstein's equations automatically satisfy the system of coupled Einstein-Maxwell and Einstein-Yang-Mills equations. In recent years, motivated by Sen's $S$-duality conjecture, there has been some renewed interest in self-dual gauge fields living on well-known Euclidean-signature manifolds. The gauge fields were studied by constructing self-dual square integrable harmonic forms on given spaces. For instance, the square integrable harmonic two-form in self-dual Taub-NUT metrics was constructed in \cite{gibbons}, its generalization to the case of complete noncompact hyper-K\"ahler spaces was given in \cite{hitchin}. In this framework, we shall report on a new exact solution that describes the Abelian gauge fields harbored by the Kerr-Taub-bolt instanton, which is a generalized example of asymptotically flat instantons with non-self-dual curvature. We shall discuss the construction of the corresponding self-dual and anti-self-dual harmonic two-forms and show that they are square integrable on the Kerr-Taub-bolt space \cite{ac}. \begin{thebibliography}{99} \bibitem{gibbons} G. W. Gibbons, Phys. Lett. B {\bf 382}, 53 (1996) \bibitem{hitchin} N. Hitchin, Commun. Math. Phys. {\bf 211}, 153 (2000) \bibitem{ac} A. N. Aliev and C. Sa\c{c}l\i o\u{g}lu, Phys. Lett. B {\bf 632}, 725 (2006) \end{thebibliography} \end{document}