May 14th, 2020

лошадь, диаграмма, Фейнман

Очень клевые лекции!

Lectures: From quantum mechanics to the Standard Model: https://arxiv.org/abs/2005.06355
Ben Gripaios
The goal of these lectures is to introduce readers with a basic knowledge of undergraduate physics (specifically non-relativistic quantum mechanics, special relativity, and electromagnetism) to the `current theory of everything': the Standard Model of particle of physics. By the end of the course, readers should be able to make predictions for simple processes at the Large Hadron Collider, such as decay rates of the Higgs boson. Some discussion of the ongoing search for physics beyond the Standard Model is also included. Based on lectures given at the Universities of Cambridge (UK) and Canterbury (New Zealand).
Comments: 67 pp


До кучи что-то от 'т Хоофта. Не вчитывался, но, кажется, интересное: https://arxiv.org/abs/2005.06374

Deterministic Quantum Mechanics: the Mathematical Equations
Gerard t Hooft
Without wasting time and effort on philosophical justifications and implications, we write down the conditions for the Hamiltonian of a quantum system for rendering it mathematically equivalent to a deterministic system. These are the equations to be considered. Special attention is given to the notion of `locality'. Various examples are worked out, followed by a systematic procedure to generate classical evolution laws and quantum Hamiltonians that are exactly equivalent. What is new here is that we consider interactions, keeping them as general as we can. The quantum systems found, form a dense set if we limit ourselves to sufficiently low energy states. The class is discrete, just because the set of deterministic models containing a finite number of classical states, is discrete. In contrast with earlier suspicions, the gravitational force turns out not to be needed for this; it suffices that the classical system act at a time scale much smaller than the inverse of the maximum scattering energies considered.
Comments: 21 pages, 1 figure, Subm. to the Article Collection: "Towards a Local Realist View of the Quantum Phenomenon", Frontiers Research Topic, ed. A.~Csado et al
лошадь, диаграмма, Фейнман

Модель лесного пожара и самоорганизованная критичность

Применимо также к эпидемиям, слухам и т.п. Специально для andreeva_anka :)

The Forest Fire Model: The subtleties of criticality and scale invariance: https://arxiv.org/abs/2005.06387
Lorenzo Palmieri, Henrik Jeldtoft Jensen
Amongst the numerous models introduced with SOC, the Forest Fire Model (FFM) is particularly attractive for its close relationship to stochastic spreading, which is central to the study of systems as diverse as epidemics, rumours, or indeed, fires. However, since its introduction, the nature of the model's scale invariance has been controversial, and the lack of scaling observed in many studies diminished its theoretical attractiveness. In this study, we analyse the behaviour of the tree density, the average cluster size and the largest cluster and show that the model could be of high practical relevance for the activation dynamics seen in brain and rain studies. From this perspective, its peculiar scaling properties should be regarded as an asset rather than a limitation.
Comments: 18 pages, 10 figures