Tootfinder

A Detailed Configuration Accounting for the Hot Plasma Bound-Free Opacity Calculation
Alina Nadezhkina, Mikhail Vronskiy
https://arxiv.org/abs/2508.11815 https://

A Detailed Configuration Accounting for the Hot Plasma Bound-Free Opacity Calculation
The calculation of the hot plasma bound-free opacity according to the average atom models often leads to a noticeable effect of initial configuration on the shell ionization threshold. For the related problem of taking into account the impact of configurations while calculating bound-bound opacity, G. Hazak and Y. Kurzweil developed a method within the Super Transition Arrays approach. Fourier transform method is the adaptation of their method for a Detailed Configurations Accounting. The bound…

Listening to CBC Radio Barrie this morning and they were interviewing the manager responsible for housing starts for the Town of Innisfil. The discussion was about missed targets for housing starts and what can be done to get back on track. You could tell that he was frustrated, but the reason for less homes being built was almost solely put on the downturn in the housing market. No one is buying, so private industry isn't building.
All levels of government are throwing money at the problem, with most of it incentivizing for-profit companies to put shovels in the ground. At some point, the Federal, Provincial, and Municipal governments have to realize that public housing, government leasehold development, co-operative housing, or subsidized family apartments must be considered to solve the housing shortage. Private industry will never have the same objectives of getting families into homes - without a calculation of significant profits first.
#CanPoli #AffordableHousing

Addressing the sign-problem in Euclidean path integrals with radial basis function neural networks
Gabor Balassa
https://arxiv.org/abs/2510.01695 https://a…

Addressing the sign-problem in Euclidean path integrals with radial basis function neural networks
Solving interacting field theories at finite densities remains a numerically and conceptually challenging task, even with modern computational capabilities. In this paper, we propose a novel approach based on an expansion of the Euclidean path integrals using radial basis function neural networks, which allows the calculation of observables at finite densities and overcomes the sign problem in a numerically very efficient manner. The method is applied to an interacting complex scalar field theo…

Nevanlinna-Pick interpolation from uncertain data
Sarah Fields, Norman Christ
https://arxiv.org/abs/2510.12136 https://arxiv.org/pdf/2510.12136

Nevanlinna-Pick interpolation from uncertain data
The calculation of inclusive processes that involve the production of many particles is a challenge for lattice QCD, a Euclidean-space method that is far removed from real-time, multiparticle production. A new approach to this problem based on Nevanlinna-Pick interpolation has been proposed by Bergamaschi et al. Here we extend their method by exploring the propagation of the statistical and systematic errors that accompany a lattice QCD calculation through this interpolation process. A simplifi…

Approximate calculation of multidimensional first passage times
James F. Lutsko
https://arxiv.org/abs/2508.21607 https://arxiv.org/pdf/2508.21607

Approximate calculation of multidimensional first passage times
The general, multidimensional barrier crossing problem for diffusive processes under the action of conservative forces is studied with the goal of developing tractable approximations. Particular attention is given to the effect of different statistical interpretations of the stochastic differential equation and to the relation between the approximations and the known, exact solutions to the one-dimensional problem. Beginning with a reasonable, but heuristic, simplifying assumption, a one-dimens…

Reweighting scheme for the calculation of grand-canonical expectation values in quantum Monte Carlo simulations with a fermion sign problem
Paul Hamann, Jan Vorberger, Tobias Dornheim
https://arxiv.org/abs/2508.18935

Reweighting scheme for the calculation of grand-canonical expectation values in quantum Monte Carlo simulations with a fermion sign problem
Ab initio path integral Monte Carlo (PIMC) simulations constitute the gold standard for the estimation of a broad range of equilibrium properties of a host of interacting quantum many-body systems spanning conditions from ultracold atoms to warm dense quantum plasmas. A key practical limitation is given by the notorious fermion sign problem, which manifests as an exponential computational bottleneck with respect to system size and inverse temperature. In practice, the sign problem is particular…

Conformal four-point ladder integrals in diverse dimensions and polylogarithms
S. E. Derkachov, A. P. Isaev, L. A. Shumilov
https://arxiv.org/abs/2510.04235 https://

Conformal four-point ladder integrals in diverse dimensions and polylogarithms
In the paper, the family of conformal four-point ladder diagrams in arbitrary space-time dimensions is considered. We use the representation obtained via explicit calculation using the operator approach and conformal quantum mechanics to study their properties, such as symmetries, loop and dimensional shift identities. In even integer dimensions, latter allows one to reduce the problem to two-dimensional case, where the notable factorization holds. Additionally, for a specific choice of propaga…

Axioms for the Measure of Evidence
Christopher D. Fiorillo, Min Sheo Choi, Jaime Gomez-Ramirez
https://arxiv.org/abs/2509.07033 https://arxiv.org/pdf/2509.…

Axioms for the Measure of Evidence
There has not been an established mathematical measure of evidence. Some Bayesians have argued that probability can be an objectively correct measure of ``rational degrees of belief,'' which we do not distinguish from evidence. However, support for the objectivist view has been limited due to the lack of a general method for assigning probabilities to evidence (belief) de novo. The standard axioms of Kolmogorov and Cox solve only the calculation problem, specifying how probabilities can be calc…

An Elementary Proof of the Nonexistence of Tarski Monster Groups of Exponent 3
Hiroshi Arai
https://arxiv.org/abs/2510.00081 https://arxiv.org/pdf/2510.000…

An Elementary Proof of the Nonexistence of Tarski Monster Groups of Exponent 3
It is well known that Tarski monster groups of exponent~3 do not exist. Traditional proofs rely on deep structural results, such as the restricted Burnside problem, properties of the free Burnside group, or Engel-type identities, and involve substantial technical computations. In this note we give a fully elementary proof: the argument reduces to a single simple identity, expressed as a key equation, whose verification requires only a brief calculation.

Efficient Estimation of Temporal Exceeding Probability for Ship Responses in Broadband Wave Fields
Shayesteh Hafezi, Xianliang Gong, Yulin Pan
https://arxiv.org/abs/2508.20271 h…

Efficient Estimation of Temporal Exceeding Probability for Ship Responses in Broadband Wave Fields
In this paper, we develop an efficient method to evaluate the temporal exceeding probability of ship motion (percentage of time for the ship motion to be above a given high threshold) in an irregular wave field. Our method builds on our previous work of Gong et al. (Applied Ocean Research, 2022), which converts the calculation into a sampling problem in the space of wave group parameters, within which an acquisition-based sequential sampling method is developed to reduce the number of required …

Solution to the uncertainty problem of nuclear matrix element for neutrinoless double-$\beta$ decay
J. Terasaki, O. Civitarese
https://arxiv.org/abs/2509.16605 https://

Solution to the uncertainty problem of nuclear matrix element for neutrinoless double-$β$ decay
The neutrinoless double-$β$ decay ($0νββ$) of nuclei is one of the major research subjects of neutrino physics nowadays because of its influence on particle physics and astrophysics. The predicted nuclear matrix elements (NMEs) of the $0νββ$ decay have a large uncertainty depending on the models used to calculate them. This problem has affected the development of neutrino physics for many years. We have performed, recently, the calculation of the NMEs for the $0νββ$ and two-neutrino d…

Novel distributional Laplacians and a Coulomb-gauge problem
V. Hnizdo, G. Vaman
https://arxiv.org/abs/2509.00282 https://arxiv.org/pdf/2509.00282

Novel distributional Laplacians and a Coulomb-gauge problem
Novel distributional Laplacians of an arsinh function and a related logarithm function are derived. The method used to establish the former result is employed in a calculation of the gauge transformation function for the case of a uniformly moving point charge.

Vibrational Spectra of Materials and Molecules from Partially-Adiabatic Elevated-Temperature Centroid Molecular Dynamics
Jorge Castro, George Trenins, Venkat Kapil, Mariana Rossi
https://arxiv.org/abs/2508.16246

Vibrational Spectra of Materials and Molecules from Partially-Adiabatic Elevated-Temperature Centroid Molecular Dynamics
Centroid molecular dynamics (CMD) incorporates nuclear quantum statistics into the calculation of vibrational spectra. However, when performed in Cartesian coordinates, CMD shows serious unphysical artifacts in certain vibrational bands, known as the curvature problem. Recent work showed that CMD spectra can be freed from the curvature problem by evolving the ring-polymer centroid on a potential of mean force (PMF) calculated at an elevated temperature ($T_e$-CMD). Here we present a partially-a…