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For quantum fields on a curved spacetime with an Euclidean section, we derive a general expression for the stress energy tensor two-point function in terms of the effective action. The renormalized two-point function is given in terms of…

General Relativity and Quantum Cosmology · Physics 2016-08-31 Nicholas G. Phillips , B. L. Hu

In the warm dark matter scenario, the Press-Schechter formalism is valid only for galaxy masses greater than the "velocity dispersion cut-off". In this work we extend the predictions to masses below the velocity dispersion cut-off, and…

Astrophysics of Galaxies · Physics 2022-11-24 Bruce Hoeneisen

We highlight the latest developments in computing higher-order scattering amplitudes with massive internal propagators. The contributing Feynman integrals often lead to special classes of functions, for example, functions associated with…

High Energy Physics - Phenomenology · Physics 2022-07-26 Ekta Chaubey

We are exploring variations of the Novikov equation that have weak solutions called peakons. Our focus is on a two-component Novikov equation with a non-self-adjoint $4\times 4$ Lax operator for which we examine the related forward and…

Exactly Solvable and Integrable Systems · Physics 2023-12-20 Xiang-Ke Chang , Jacek Szmigielski

We investigate spectral functions of matter-gauge theories that are asymptotically free in the ultraviolet and display a Banks-Zaks conformal fixed point in the infrared. Using perturbation theory, Callan-Symanzik resummations, and UV-IR…

High Energy Physics - Theory · Physics 2023-02-01 Yannick Kluth , Daniel Litim , Manuel Reichert

The spectral density function describes the second-order properties of a stationary stochastic process on $\mathbb{R}^d$. This paper considers the nonparametric estimation of the spectral density of a continuous-time stochastic process…

Statistics Theory · Mathematics 2023-02-07 Rafail Kartsioukas , Stilian Stoev , Tailen Hsing

The dynamic spectra of pulsars frequently exhibit diverse interference patterns, often associated with parabolic arcs in the Fourier-transformed (secondary) spectra. Our approach differs from previous ones in two ways: first, we extend…

High Energy Astrophysical Phenomena · Physics 2024-05-28 Tobias Kramer , Daniel Waltner , Eric J. Heller , Dan R. Stinebring

Adapting the powerful integrability-based formalism invented previously for the calculation of gluon scattering amplitudes at strong coupling, we develop a method for computing the holographic three point functions for the large spin limit…

High Energy Physics - Theory · Physics 2012-07-04 Yoichi Kazama , Shota Komatsu

We investigated the effect of inverse Compton scattering in mildly relativistic static and moving plasmas with low optical depth using Monte Carlo simulations, and calculated the Sunyaev-Zel'dovich effect in the cosmic background radiation.…

Astrophysics · Physics 2009-10-31 S. M. Molnar , M. Birkinshaw

The design of fixed point algorithms is at the heart of monotone operator theory, convex analysis, and of many modern optimization problems arising in machine learning and control. This tutorial reviews recent advances in understanding the…

Optimization and Control · Mathematics 2022-07-19 Francesco Bullo , Pedro Cisneros-Velarde , Alexander Davydov , Saber Jafarpour

We demonstrate that the Balitsky-JIMWLK equations describing the high-energy evolution of the n-point functions of the Wilson lines (the QCD scattering amplitudes in the eikonal approximation) admit a controlled mean field approximation of…

High Energy Physics - Phenomenology · Physics 2015-06-03 E. Iancu , D. N. Triantafyllopoulos

In perturbation theory, the spectral densities of two-point functions develop non-integrable threshold singularities at higher orders. In QCD, such singularities emerge when calculating the diagrams in terms of the pole quark mass, and they…

High Energy Physics - Phenomenology · Physics 2021-01-20 Dmitri Melikhov , Silvano Simula

We provide an efficient method to evaluate the generalized Stieltjes constants $\gamma_n(a)$ numerically to arbitrary accuracy for large $n$ and $n \gg |a|$ values. The method uses an integral representation for the constants and evaluates…

Numerical Analysis · Mathematics 2022-12-21 Sandeep Tyagi

Using the Green function integral representation the Dyson-Schwinger equations are solved directly in Minkowski space. Essential ideas of the spectral techniques are discussed and applied on two renormalizable models: the Yukawa theory with…

High Energy Physics - Phenomenology · Physics 2014-11-17 Vladimir Sauli

In previous papers of this series, we presented a formalism able to account for both statistical equilibrium of a multilevel atom and coherent and incoherent scatterings (partial redistribution). aims: This paper provides theoretical…

Solar and Stellar Astrophysics · Physics 2017-11-15 V. Bommier

In this work, we consider the weighted difference of two independent complex Wishart matrices and derive the joint probability density function of the corresponding eigenvalues in a finite-dimension scenario using two distinct approaches.…

Mathematical Physics · Physics 2020-11-17 Santosh Kumar , S. Sai Charan

We study the densities of limiting distributions of squared singular values of high-dimensional matrix products composed of independent complex Gaussian (complex Ginibre) and truncated unitary matrices which are taken from Haar distributed…

Probability · Mathematics 2015-12-23 Thorsten Neuschel

An extended two-hadron operator is developed to extract the spectra of irreducible representations (irreps) in the finite volume. The irreps of the group for the finite volume system are projected using a coordinate-space operator. The…

High Energy Physics - Lattice · Physics 2022-05-04 Jia-Jun Wu , Waseem Kamleh , Derek B. Leinweber , Yan Li , Gerrit Schierholz , Ross D. Young , James M. Zanotti

We develop a spectrally accurate numerical method to compute solutions of a model partial differential equation used in plasma physics to describe diffusion in velocity space due to Fokker-Planck collisions. The solution is represented as a…

Classical Analysis and ODEs · Mathematics 2015-03-18 Jon Wilkening , Antoine Cerfon

We introduce a numerical method for computing spectral densities, and apply it to the evaluation of the local density of states (LDOS) of sparse Hamiltonians derived from tight-binding models. The approach, which we call the high-order…

Computational Physics · Physics 2025-12-04 Jinjing Yi , Daniel Massatt , Andrew Horning , Mitchell Luskin , J. H. Pixley , Jason Kaye