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Related papers: D_k Gravitational Instantons and Nahm Equations

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We provide a description of the moduli space of framed autodual instanton bundles on projective space, focusing on the particular cases of symplectic and orthogonal instantons. Our description will use the generalized ADHM equations which…

Algebraic Geometry · Mathematics 2016-11-09 Marcos Jardim , Simone Marchesi , Anna Wißdorf

We prove infinitesimal rigidity and integrability of the moduli space for Hermitian gravitational instantons. Together with the recent proof by Biquard, Gauduchon, and LeBrun of local rigidity for Hermitian instantons, this completes the…

Differential Geometry · Mathematics 2026-01-27 Lars Andersson , Bernardo Araneda

In this article, we study the DKP equation for the oscillator in a G\"{o}del-type space-time background. We derive the final form of this equation in a flat class of G\"{o}del-type space-time and solve it analytically, and evaluate the…

High Energy Physics - Theory · Physics 2020-02-11 Faizuddin Ahmed

All non-twisting Petrov-type N solutions of vacuum Einstein field equations with cosmological constant Lambda are summarized. They are shown to belong either to the non-expanding Kundt class or to the expanding Robinson-Trautman class.…

General Relativity and Quantum Cosmology · Physics 2009-10-31 J. Bicak , J. Podolsky

We study the asymptotic behavior of solutions of discrete nonlinear Schr\"odinger-type (DNLS) equations. For a conservative system, we consider the global in time solvability and the question of existence of standing wave solutions.…

Classical Analysis and ODEs · Mathematics 2007-05-23 Nikos I. Karachalios , Athanasios N. Yannacopoulos

For an asymptotically locally Euclidean (ALE) or asymptotically locally flat (ALF) gravitational instanton $(M,g)$ with toric symmetry, we express the signature of $(M,g)$ directly in terms of its rod structure. Applying…

Differential Geometry · Mathematics 2024-08-02 Gustav Nilsson

We construct infinitely many real-valued, time-periodic breather solutions of power-type nonlinear wave equations. These solutions are obtained from critical points of a dual functional and they are weakly localized in space. Our abstract…

Analysis of PDEs · Mathematics 2021-08-11 Rainer Mandel , Dominic Scheider

We make some comments on noncommutative $U(N)$-instantons on $\mathbb{R}^4_{\theta}$. We elaborate on the equations for the ASD-connection for free modules. Further we make some remarks on the computation of the topological index of ADHM…

Differential Geometry · Mathematics 2015-03-06 Nikolay A. Ivanov

We revisit the generalised ADHM construction for instantons in non-commutative space using a manifestly quaternionic formalism. This leads to an identification of the self-dual part of theta^mn as the imaginary part of the size modulus of…

High Energy Physics - Theory · Physics 2007-05-23 Robert C. Helling

We study electrically charged, dilaton black holes, which possess infinitesimal angular momentum in the presence of one or two Liouville type potentials. These solutions are neither asymptotically flat nor (anti)-de Sitter. Some properties…

High Energy Physics - Theory · Physics 2008-11-26 A. Sheykhi , N. Riazi

In this paper we show that one can have asymptotically de Sitter (dS), anti-de Sitter (AdS) and flat solutions in Gauss-Bonnet gravity without any need to a cosmological constant term in field equations. First, we introduce static solutions…

High Energy Physics - Theory · Physics 2009-11-10 M. H. Dehghani

We present an account of the ADHM construction of instantons on Euclidean space-time $\mathbb{R}^4$ from the point of view of noncommutative geometry. We recall the main ingredients of the classical construction in a coordinate algebra…

Mathematical Physics · Physics 2011-05-05 Simon Brain , Walter D. van Suijlekom

We study various aspects of four dimensional Einstein-Maxwell multicentred gravitational instantons. These are half-BPS Riemannian backgrounds of minimal N=2 supergravity, asymptotic to R^4, R^3 x S^1 or AdS_2 x S^2. Unlike for the…

High Energy Physics - Theory · Physics 2008-11-26 Maciej Dunajski , Sean A. Hartnoll

D-instantons are used to probe the near-horizon geometry of D3-branes systems on orbifold spaces. For fractional D3-branes, D-instanton calculus correctly reproduces the gauge beta-function and U(1)_R anomaly of the corresponding N=2…

High Energy Physics - Theory · Physics 2015-06-26 Alessandro Tanzini

We derive exact magnetically charged, static and spherically symmetric black hole solutions of the four-dimensional Einstein-Born-Infeld-dilaton gravity. These solutions are neither asymptotically flat nor (anti)-de Sitter. The properties…

High Energy Physics - Theory · Physics 2009-11-11 Stoytcho S. Yazadjiev

Oscillatons are solutions of the coupled Einstein-Klein-Gordon (EKG) equations that are globally regular and asymptotically flat. By means of a Legendre transformation we are able to visualize the behaviour of the corresponding objects in…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Octavio Obregon , L. Arturo Urena-Lopez , Franz E. Schunck

This paper develops a local analogue of the ADHM construction, which characterises ASD instantons defined over smooth bounded domains inside Euclidean $\mathbb{R}^4$ diffeomorphic to the 4-ball, in terms of infinite dimensional Hilbert…

Differential Geometry · Mathematics 2017-12-05 Yang Li

This article investigates a set of partial differential equations, the DT-instanton equations, whose solutions can be regarded as a generalization of the notion of Hermitian-Yang-Mills connections. These equations owe their name to the hope…

Differential Geometry · Mathematics 2021-11-03 Gavin Ball , Goncalo Oliveira

We study in detail the ADHM construction of U(N) instantons on noncommutative Euclidean space-time R_{NC}^4 and noncommutative space R_{NC}^2 x R^2. We point out that the completeness condition in the ADHM construction could be invalidated…

High Energy Physics - Theory · Physics 2009-11-07 Chong-Sun Chu , Valentin V. Khoze , Gabriele Travaglini

We systematically derive the asymptotically flat five dimensional black rings in EMd gravity by using the sigma model structure of the dimensionally reduced field equations. New non-asymptotically flat EMd black ring solutions in five…

High Energy Physics - Theory · Physics 2007-05-23 Stoytcho S. Yazadjiev