Results 31 to 40 of about 16,811 (181)
Journal of Time Series Analysis, EarlyView.ABSTRACT The paper deals with the construction of a synthetic indicator of economic growth, obtained by projecting a quarterly measure of aggregate economic activity, namely gross domestic product (GDP), into the space spanned by a finite number of smooth principal components, representative of the medium‐to‐long‐run component of economic growth of a ...
Alessandro Giovannelli +2 more
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Fractal and FractionalThe Lax pairs of the higher-order Gerdjikov–Ivanov (HOGI) equation are extended to the multi-component formula. Then, we first derive four different types of nonlocal group reductions to this new system.
Jinshan Liu +3 more
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On the Riemann-Hilbert problem in multiply connected domains
Open Mathematics, 2016 We proved the existence of multivalent solutions with the infinite number of branches for the Riemann-Hilbert problem in the general settings of finitely connected domains bounded by mutually disjoint Jordan curves, measurable coefficients and measurable
Ryazanov Vladimir
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Kubo-Martin-Schwinger relation for an interacting mobile impurity
Physical Review Research, 2023 In this work we study the Kubo-Martin-Schwinger (KMS) relation in the Yang-Gaudin model of an interacting mobile impurity. We use the integrability of the model to compute the dynamic injection and ejection Green's functions at finite temperatures.
Oleksandr Gamayun +2 more
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The Huang–Yang Formula for the Low‐Density Fermi Gas: Upper Bound
Communications on Pure and Applied Mathematics, Volume 79, Issue 8, Page 1919-1972, August 2026.ABSTRACT We study the ground state energy of a gas of spin 1/2$1/2$ fermions with repulsive short‐range interactions. We derive an upper bound that agrees, at low density ϱ$\varrho$, with the Huang–Yang conjecture. The latter captures the first three terms in an asymptotic low‐density expansion, and in particular the Huang–Yang correction term of order
Emanuela L. Giacomelli +3 more
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Weyl metrics and Wiener-Hopf factorization
Journal of High Energy Physics, 2020 We consider the Riemann-Hilbert factorization approach to the construction of Weyl metrics in four space-time dimensions. We present, for the first time, a rigorous proof of the remarkable fact that the canonical Wiener-Hopf factorization of a matrix ...
P. Aniceto +3 more
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Conditional Symmetries and Riemann Invariants for Hyperbolic Systems of PDEs
, 2007 This paper contains an analysis of rank-k solutions in terms of Riemann invariants, obtained from interrelations between two concepts, that of the symmetry reduction method and of the generalized method of characteristics for first order quasilinear ...
Huard, Benoit, Grundland, A. Michel
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Invariant Measure and Universality of the 2D Yang–Mills Langevin Dynamic
Communications on Pure and Applied Mathematics, Volume 79, Issue 8, Page 1973-2102, August 2026.ABSTRACT We prove that the Yang–Mills (YM) measure for the trivial principal bundle over the two‐dimensional torus, with any connected, compact structure group, is invariant for the associated renormalised Langevin dynamic. Our argument relies on a combination of regularity structures, lattice gauge‐fixing and Bourgain's method for invariant measures ...
Ilya Chevyrev, Hao Shen
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The inverse scattering transform in the form of a Riemann-Hilbert problem for the Dullin-Gottwald-Holm equation [PDF]
Opuscula Mathematica, 2017 The Cauchy problem for the Dullin-Gottwald-Holm (DGH) equation \[u_t-\alpha^2 u_{xxt}+2\omega u_x +3uu_x+\gamma u_{xxx}=\alpha^2 (2u_x u_{xx} + uu_{xxx})\] with zero boundary conditions (as \(|x|\to\infty\)) is treated by the Riemann-Hilbert approach to
Dmitry Shepelsky, Lech Zielinski
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The Riemann Hilbert problem for generalized Q-holomorphic functions
, 2010 In this work, the classical Riemann Hilbert boundary value problem is extended to generalized Q-holomorphic ...
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