SciPost News

We are pleased to welcome ETH Zürich as our latest Sponsor! Many thanks to this institution and its local scientists for supporting our efforts. This sponsorship will help sustain our services to the academic community (see https://scipost.org/finances/business_model/ for a rundown on our business model) and facilitate our continuing expansion.

Today marks the start of our publishing activities in the field of Astronomy: our new journal SciPost Astronomy has been officially launched with the publication of its very first paper:

Bonsai-SPH: A GPU accelerated astrophysical Smoothed Particle Hydrodynamics code
by Jeroen Bédorf and Simon Portegies Zwart.

Warm congratulations to the authors for pioneering this new title!

SciPost Astronomy represents the first of a series of new journals in fields beyond Physics, which we are currently planning to establish as part of our broad expansion strategy.

"Exceptional Chern-Simons-Matter dualities" by Clay Cordova, Po-Shen Hsin, Kantaro Ohmori has received the Select label. Warm congratulations to the author!

This well-structured paper fills the gap in literature regarding how the exceptional groups fit into topological quantum field theories for classical Lie groups. The authors first give a concise, helpful presentation of some mathematically rigorous facts about topological quantum field theories with exceptional gauge groups. Then, they developed a set of new families of Chern-Simons theories. This is done exploiting the conformal embedding technique for the corresponding chiral algebras, as well as with the aid of some results concerning more formal aspects of Kac-Moody algebras. With the new dualities for topological Chern-Simons theories, the authors proceed to formulate an array of conjectures regarding the Chern-Simons-matter dualities with scalar matter. Finally, they use them to determine candidate phase diagrams of time-reversal invariant G2 gauge theory coupled to either an adjoint fermion, or two fundamental fermions.

"General continuum model for twisted bilayer graphene and arbitrary smooth deformations" by Leon Balents has received the Select label. Warm congratulations to the author!

Moiré patterns can affect the low energy electronic structure in twisted bilayer graphene and provide an unprecedented platform for correlated electron physics. In this clear paper, the author uses a simple derivation of a continuum Hamiltonian to calculate the low energy electronic band structure. The original continuum model written in the momentum space is hard to use when lattice relaxation and strain effects come in. To solve this issue, the current paper derives the continuum model in real space, which can easily incorporate strain effects. With this new method, the author provides a unified method to study twisted graphene structures including all the important electronic structure physics. It may also be helpful for future studies of disorder effects in these systems.

"Logarithmic correlation functions for critical dense polymers on the cylinder" by Alexi Morin-Duchesne and Jesper Lykke Jacobsen has received the Select label. Warm congratulations to the authors!

In this paper, the authors have studied the complex issue of correlation functions in the dense polymer problem. Demonstrating formidable mathematical skills, they are able to express the results in terms of integral formulae and hypergeometric functions. These lattice results were then used to compute structure constants and ratios that appear in the operator product expansions of the boundary condition changing fields. The log-conformal field theories presented in this paper are of special interest in the field of condensed matter theory, as they represent the case where some of the fields are logarithmic instead of primary and thus do not undergo simple multiplicative scale changes under dilation. These results can lead to better understanding of many interesting models like the sandpile model, dense polymers, and critical percolation.

"The self-consistent quantum-electrostatic problem in strongly non-linear regime" by Pacome Armagnat, A. Lacerda-Santos, Benoit Rossignol, Christoph Groth and Xavier Waintal has received the Select label. Warm congratulations to the authors!

In this well written and detailed paper, the authors propose an effective method to solve "the self-consistent quantum-electrostatic problem" at zero temperature. Commonly, this problem has been avoided, but the authors of these paper present a stable algorithm that provides a solution to this problem with controlled accuracy. The main result of the manuscript is eliminating the convergence issues of the Schrodinger-Poisson problem and reducing the necessity to perform computationally intensive steps of quantum simulation to only a few iterations. Overall, this proposal can be very valuable to many researchers that have to address this problem in some form in their modelling of physical phenomena.

"Exact real-time dynamics of single-impurity Anderson model from a single-spin hybridization-expansion" by P. Kubiczek, A. N. Rubtsov and A. I. Lichtenstein has received the Select label. Warm congratulations to the authors!

This novel paper presents a new computational approach for dynamics of quantum impurity models and other relevant topics for the condensed matter field. In particular, the authors present a modified real-time continuous-time hybridization-expansion quantum Monte Carlo solver for a time-dependent single-orbital Anderson impurity model. The presented method alleviates the dynamical sign problem by reducing the order of sampled diagrams and makes it possible to reach twice as long time scales in comparison to the standard method. This method is illustrated by calculating electric current through impurity in paramagnetic and spin-polarized cases. The idea of expanding around one single spin flavour could lead to further developments in the understanding of the cross-over between Falicov-Kimball and Hubbard physics.

"Thermal conformal blocks" by Yan Gobeil, Alexander Maloney, Gim Seng Ng and Jie-qiang Wu has received the Select label. Warm congratulations to the authors!

This innovative article explores a foundational problem of determining the conformal blocks for a conformal field theory (CFT) at finite temperatures. They solve this issue for the specific case of one-point thermal correlators. The combination of field theoretic and holographic techniques gives confidence in the veracity of the result, and suggests how one might extend their result to other related blocks. This topic has not been explored in detail before, and therefore this article establishes the groundwork for future research.