English
Related papers

Related papers: Quadratic closed G2-structures

200 papers

We show that a certain class of vortex blob approximations for ideal hydrodynamics in two dimensions can be rigorously understood as solutions to the equations of second-grade non-Newtonian fluids with zero viscosity, and initial data in…

Analysis of PDEs · Mathematics 2025-10-20 Marcel Oliver , Steve Shkoller

We describe a highly efficient numerical scheme for finding two-sided bounds for the eigenvalues of the fractional Laplace operator (-Delta)^{alpha/2} in the unit ball D in R^d, with a Dirichlet condition in the complement of D. The…

Analysis of PDEs · Mathematics 2017-05-17 Bartłomiej Dyda , Alexey Kuznetsov , Mateusz Kwaśnicki

This work introduces a port-Hamiltonian (PH) model for constrained mechanical systems, which is directly derived from the Lagrangian equations of motion. The present PH framework incorporates a singularity-free director representation of…

Dynamical Systems · Mathematics 2026-03-16 Lisa Latussek , Philipp L. Kinon , Peter Betsch

We consider the problem of ergodicity for the $P(\Phi)_2$ measure of quantum field theory under the flow of the singular stochastic (damped) wave equation $u_{tt} + u_t + (1-\Delta) u + {:}\,p(u)\mspace{2mu}{:} = \sqrt 2 \xi$, posed on the…

Probability · Mathematics 2023-10-04 Leonardo Tolomeo

In this paper the notion of an EPR state for the composite S of two quantum systems S1, S2, relative to S2 and a set O of bounded observables of S2, is introduced in the spirit of classical examples of Einstein-Podolsky-Rosen and Bohm. We…

Quantum Physics · Physics 2009-10-31 Richard Arens , V. S. Varadarajan

Assessing the applicability of hydrodynamic expansions close to phase transition points is crucial from either theoretical or phenomenological points of view. We explore this within the gauge/gravity duality, using the Einstein-Klein-Gordon…

High Energy Physics - Theory · Physics 2024-08-07 F. Taghinavaz

This memoir contains an overview of the proof of the bounded $L^2$ curvature conjecture. More precisely we show that the time of existence of a classical solution to the Einstein-vacuum equations depends only on the $L^2$-norm of the…

Analysis of PDEs · Mathematics 2013-01-21 Sergiu Klainerman , Igor Rodnianski , Jeremie Szeftel

In this paper, we consider the well-known following shape optimization problem: $$\lambda_2(\Omega^*)=\min_{\stackrel{|\Omega|=V_0} {\Omega\textrm{ convex}}} \lambda_2(\Omega),$$ where $\lambda_2(\Om)$ denotes the second eigenvalue of the…

Optimization and Control · Mathematics 2010-11-01 Jimmy Lamboley

We show that the symmetry operators for the quantum superintegrable system on the 3-sphere with generic 4-parameter potential form a closed quadratic algebra with 6 linearly independent generators that closes at order 6 (as differential…

Mathematical Physics · Physics 2011-05-31 Ernie G. Kalnins , Willard Miller , Sarah Post

A general appearance of two-pole structures is exhibited in a relativistic Friedrichs-Lee model combined with a relativistic quark pair creation model in a consistent manner. This kind of two-pole structure could be found when a $q\bar q$…

High Energy Physics - Phenomenology · Physics 2021-07-21 Zhi-Yong Zhou , Zhiguang Xiao

This is the first of a sequence of four papers \cite{param1}, \cite{param2}, \cite{param3}, \cite{param4} dedicated to the construction and the control of a parametrix to the homogeneous wave equation $\square_{\bf g} \phi=0$, where ${\bf…

Analysis of PDEs · Mathematics 2012-04-10 Jeremie Szeftel

In this note, we construct new solutions to the heterotic $\mathrm{G}_2$-system with non-abelian gauge group, both compact and non-compact, on certain $2$-step nilmanifolds and $3$-Sasakian manifolds. Our approach is based on an ansatz that…

Differential Geometry · Mathematics 2026-05-08 Viviana del Barco , Udhav Fowdar , Andrés J. Moreno

We study the phases and phase transition lines of the finite temperature G(2) Higgs model. Our work is based on an efficient local hybrid Monte-Carlo algorithm which allows for accurate measurements of expectation values, histograms and…

High Energy Physics - Lattice · Physics 2011-06-08 Björn H. Wellegehausen , Andreas Wipf , Christian Wozar

This paper presents a high-order discontinuous Galerkin finite element method to solve the barotropic version of the conservative symmetric hyperbolic and thermodynamically compatible (SHTC) model of compressible two-phase flow, introduced…

Numerical Analysis · Mathematics 2025-01-29 Laura Río-Martín , Michael Dumbser

In this paper, it is shown that any well-posed 2nd order PDE can be reformulated as a well-posed first order least squares system. This system will be solved by an adaptive wavelet solver in optimal computational complexity. The…

Numerical Analysis · Mathematics 2017-11-17 Nikolaos Rekatsinas , Rob Stevenson

Let g be a G-invariant Einstein metric on a compact homogeneous space M=G/K. We use a formula for the Lichnerowicz Laplacian of g at G-invariant TT-tensors to study the stability type of g as a critical point of the scalar curvature…

Differential Geometry · Mathematics 2022-06-20 Jorge Lauret

Weakly nonlinear analysis of resonant PDEs in recent literature has generated a number of resonant systems for slow evolution of the normal mode amplitudes that possess remarkable properties. Despite being infinite-dimensional Hamiltonian…

Exactly Solvable and Integrable Systems · Physics 2019-06-14 Anxo Biasi , Piotr Bizon , Oleg Evnin

We study the problem of existence of solutions for generalized backward stochastic differential equation with two reflecting barriers (GRBSDE for short) under weaker assumptions on the data. Roughly speaking we show the existence of a…

Probability · Mathematics 2011-03-29 E. H. Essaky , M. Hassani , Y. Ouknine

In general, the system of $2$nd-order partial differential equations made of the Euler-Lagrange equations of classical field theories are not compatible for singular Lagrangians. This is the so-called second-order problem. The first aim of…

Mathematical Physics · Physics 2022-02-02 David Adame-Carrillo , Jordi Gaset , Narciso Román-Roy

We use the bracket flow/algebraic soliton approach to study the Laplacian flow of $G_2$-structures and its solitons in the homogeneous case. We prove that any homogeneous Laplacian soliton is equivalent to a semi-algebraic soliton (i.e.\ a…

Differential Geometry · Mathematics 2017-05-04 Jorge Lauret