Analytical continuation of matrix-valued functions: Carathéodory formalism [PDF]
Physical review B, 2021 Finite-temperature quantum field theories are formulated in terms of Green’s functions and selfenergies on the Matsubara axis. In multi-orbital systems, these quantities are related to positive semidefinite matrix-valued functions of the Carathéodory and
Jiani Fei +3 more
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The RVP Method—From Real Ab-Initio Calculations to Complex Energies and Transition Dipoles
Frontiers in Physics, 2022 The purpose of this review is to describe the rationale behind the RVP (resonance via Padé) approach for calculating energies and widths of resonances, while emphasizing a solid mathematical ground.
Arie Landau +4 more
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Sparse modeling approach to analytical continuation of imaginary-time quantum Monte Carlo data. [PDF]
Physical Review E, 2017 A data-science approach to solving the ill-conditioned inverse problem for analytical continuation is proposed. The root of the problem lies in the fact that even tiny noise of imaginary-time input data has a serious impact on the inferred real-frequency
J. Otsuki +3 more
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Diffraction by a quarter–plane. Analytical continuation of spectral functions [PDF]
Quarterly Journal of Mechanics and Applied Mathematics, 2018 The problem of diffraction by a Dirichlet quarter-plane (a flat cone) in a 3D space is studied. The Wiener–Hopf equation for this case is derived and involves two unknown (spectral) functions depending on two complex variables.
R. Assier, A. V. Shanin
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Relating a System’s Hamiltonian to Its Entropy Production Using a Complex Time Approach
Entropy, 2023 We exploit the properties of complex time to obtain an analytical relationship based on considerations of causality between the two Noether-conserved quantities of a system: its Hamiltonian and its entropy production. In natural units, when complexified,
Michael C. Parker, Chris Jeynes
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Low-Order Scaling Quasiparticle Self-Consistent GW for Molecules
Frontiers in Chemistry, 2021 Low-order scaling GW implementations for molecules are usually restricted to approximations with diagonal self-energy. Here, we present an all-electron implementation of quasiparticle self-consistent GW for molecular systems.
Arno Förster, Lucas Visscher
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On the analytical continuation of lattice Liouville theory
Journal of High Energy Physics, 2023 The path integral of Liouville theory is well understood only when the central charge c ∈ [25, ∞). Here, we study the analytical continuation the lattice Liouville path integral to generic values of c, with a particular focus on the vicinity of c ...
Xiangyu Cao +2 more
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An analytical continuation approach for evaluating emission lineshapes of molecular aggregates and the adequacy of multichromophoric Förster theory. [PDF]
Journal of Chemical Physics, 2013 In large photosynthetic chromophore-protein complexes not all chromophores are coupled strongly, and thus the situation is well described by formation of delocalized states in certain domains of strongly coupled chromophores.
L. Banchi +3 more
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Correction of thermographic images based on the minimization method of Tikhonov functional [PDF]
Yugoslav Journal of Operations Research, 2022 The paper considers the method of correction of thermographic images (thermograms) obtained by recording in the infrared range of radiation from the surface of the object under study using a thermal imager.
Baaj Obaida +2 more
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Minimal pole representation and controlled analytic continuation of Matsubara response functions [PDF]
Physical review B, 2023 Analytical continuation is a central step in the simulation of finite-temperature field theories in which numerically obtained Matsubara data is continued to the real frequency axis for physical interpretation.
Lei Zhang, Emanuel Gull
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