November 5th, 2021

лошадь, диаграмма, Фейнман

Что-то о случайных матрицах

Возможно, будет полезно.

Introduction to Monte Carlo for Matrix Models: https://arxiv.org/abs/2111.02410
Raghav G. Jha
We consider a wide range of matrix models and study them using the Monte Carlo technique in the large N limit. The results we obtain agree with exact analytic expressions and recent numerical bootstrap methods for models with one and two matrices. We then present new results for several unsolved multi-matrix models where no other tool is yet available. In order to encourage an exchange of ideas between different numerical approaches to matrix models, we provide programs in Python that can be easily modified to study potentials other than the ones discussed. These programs were tested on a laptop and took between a few minutes to several hours to finish depending on the model, N, and the required precision.
Comments: v1: 52 pages with a few Mathematica codes, 3 Python codes, 5 tables, 10 exercises, 14 figures, and 52 references
лошадь, диаграмма, Фейнман

Что-то на португальском по мезонной спектроскопии для инженеров (!)

Espectroscopia Mesónica Moderna: o Papel Fundamental da Unitariedade: https://arxiv.org/abs/2111.02565
Eef van Beveren, George Rupp
The importance of implementing unitarity constraints in meson spectroscopy is very briefly outlined for Portuguese students of engineering sciences and therefore non-experts in the field. After explaining the profound differences between meson spectroscopy and atomic spectroscopy, attention is paid to the shortcomings of standard Breit-Wigner parametrisations in the case of broad and/or overlapping resonances. Finally, the manifestly unitary Resonance-Spectrum-Expansion model, which lies at the heart of a recent invited review paper by the present authors, is graphically presented, together with a simple yet typical application to the long-controversial K⋆0(700) resonance.
Comments: in Portuguese. Invited paper for the first new edition (no. 504) of the students journal "Técnica" published on 3 November 2021 by the "Associação dos Estudantes do Instituto Superior Técnico" of IST in Lisbon, Portugal. Article is in Portuguese language, with an English abstract; 4 pages, 5 figures. Link to published version: this https URL