SciPost News

"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.

"Entanglement evolution and generalised hydrodynamics: interacting integrable systems" by Vincenzo Alba, Bruno Bertini and Maurizio Fagotti has received the Select label. Warm congratulations to the authors!

In this very readable paper, the authors study the entanglement evolution of integrable quantum models. In particular, they focus on the entanglement entropy after a global quench from inhomogeneous states. They combine the ideas of pair particle production with the formalism of generalised hydrodynamics to develop a formula capturing the dynamics of the entanglement entropy. They found that the half chain entanglement rate depends only on the physics at the interface, and it differs from the rate of exchange of thermodynamic entropy. This contrasts with the behaviour in free or homogeneous interacting integrable systems, where the two rates coincide. These results were tested in the Heisenberg chain, finding good agreement with DMRG simulations. This paper makes interesting points regarding the definition of the entanglement entropy, and it calls attention to several interesting directions for future research.

The University of Amsterdam has recently granted 60k to SciPost. This donation makes the UvA the most generous sponsor of our initiative up to now. We will make use of these funds to further develop our services and accelerate our expansion plans.

As background to this, we have talked to Gerard Kohler from the UvA's central library. In the short interview hereby linked, he talks about the background reasons for this support, and his hopes for the future.

It is with great sadness that we mark the passing of Prof. Olga Igonkina, Nikhef particle physicist and prominent member of the ATLAS experiment at CERN. She passed away on Sunday May 19th in Amsterdam, The Netherlands, at the young age of 45.

Prof. Igonkina was a prominently active contributor to SciPost, having organized the proceedings for the 15th International Workshop on Tau Lepton Physics (Amsterdam, 2018-09). She was a Fellow of our Editorial College and was always much appreciated for her dedicated hard work and ethics. We will miss her greatly. We express our most sincere condoleances to her family, friends and further colleagues.

"Living on the walls of super-QCD" by Vladimir Bashmakov, Francesco Benini, Sergio Benvenuti, Matteo Bertolini has received the Select label. Warm congratulations to the authors!

This excellently written paper concerns the 3d theory that lives on
the domain walls of SQCD with less flavors than colors. It contains
nice insights into the interplay between 4d bulk physics and 3d
worldvolume domain walls physics. In particular, the authors propose a
class of three-dimensional Chern-Simons-matter theories to describe
the effective dynamics on the walls. Moreover, they present several
interesting results in the topic, including successful non-trivial
cross-checks of their proposal. In addition, they also provide a
review section that clarifies their presentation. Overall, these
results will be useful in future explorations of 3d non-supersymmetric
QFTs and their connections to 4d physics.

An independent study of scientific metadata collections has recently highlighted the quality of our publishing services. We cannot do better than quote the spontaneous communication we recently received from Dr Habermann:

I am a "metadata guy" in Boulder, Colorado and have recently been working to characterize scientific metadata collections in many repositories around the world. I recently took a look at the CrossRef Participation Reports and implemented a simple quantitative measure of completeness of these collections and a simple plot that compares completeness over time. I am using this approach to try to understand evolution of CrossRef metadata through time. As part of this work I looked at completeness as a function of collections size. The original dataset was a sample from CrossRef. I recently updated the sample to include all CrossRef members.

I am happy to let you know that SciPost has the most complete metadata of all 8670 CrossRef members with current collections of journal articles.

The attached Figure shows the data and you can see that SciPost clearly stands out. […]

Great work,

Ted

Readers can find more details of this study on Dr Habermann’s blog.

We are very grateful for this very interesting and rewarding piece of information, which, besides confirming the top-quality of our services, interestingly points to many aspects of metadata systems (ours and those of others) which can still be improved.

"Snell's Law for a vortex dipole in a Bose-Einstein condensate" by Michael M. Cawte, Xiaoquan Yu, Brian P. Anderson, Ashton S. Bradley has received the Select label. Warm congratulations to the authors!

This paper provides a useful guide for the behaviour of vortex dipoles as they pass through interfaces of sharply changing density, including a thorough numerical study and consequent analysis. As part of this analysis, the authors compare the values of the reflection/refraction vs. incident angles in vortex dipoles with a Snell’s law-like analytical prediction, achieving good agreement between the two before and after the interface. However, the authors found that when passing near the interface the dipole can exhibit dynamics that depart significantly from standard ray optics, involving transient capture by the interface. They conclude that despite the added complexity, an analogue Snell’s law is still applicable for the incoming and outgoing dipole paths when interacting with a sharp interface. This interesting and thorough study could guide future experiments on vortices in flattened geometries.

SciPost is very happy to announce that the University of Leiden has become a Sponsor through a generous €10 000 contribution. Based on current estimates, this is sufficient to cover the whole submission and publication process for more than 25 articles. SciPost is extremely thankful for this support, and will devote the resources to its services for the academic community worldwide.

"A classical density functional from machine learning and a convolutional neural network" by Shang-Chun Lin and Martin Oettel has received the Select label. Warm congratulations to the authors!

This brilliant paper presents an inspiring conceptual DFT study, using machine learning methods to approximate a classical density functional, obtaining precise data for density distributions in given external potentials. In addition, they relate these simulations to their theoretical considerations, which encompass a variety of elements from classical liquid state theory to machine learning techniques. Conceptually, this goes far beyond what has been done in electronic structure DFT using machine learning. The hybrid approach of the current paper gives much insight into the formal (analytical) structure of the attractive contribution to the excess free energy functional. With the increasing use of machine learning, this study points towards the future direction on how to use it in the field of DFT.