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Detailed description of the calculation of the 2-loop self-energy for a scalar particle is presented. By employing a simple sector decomposition method, the ultraviolet divergent part is efficiently separated from the finite part. The resulting expression can be used for both analytic and numerical computation to renormalize the divergence and to provide finite results for physics.
Research on the birth and evolution of life are reviewed with reference to the maximum entropy production principle (MEPP). It has been shown that this principle is essential for consistent understanding of the birth and evolution of life. First, a recent work for the birth of a self-replicative system as pre-RNA life is reviewed in relation to the MEPP. A critical condition of polymer concentration in a local system is reported by a dynamical system approach, above which, an exponential increase of entropy production is guaranteed. Secondly, research works of early stage of evolutions are reviewed; experimental research for the numbers of cells necessary for forming a multi-cellular organization, and numerical research of differentiation of a model system and its relation with MEPP. It is suggested by this review article that the late stage of evolution is characterized by formation of society and external entropy production. A hypothesis on the general route of evolution is discussed from the birth to the present life which follows the MEPP. Some examples of life which happened to face poor thermodynamic condition are presented with thermodynamic discussion. It is observed throug
Large-scale circulation (LSC) quasi-stably emerges in the turbulent Rayleigh-Bénard convection, and intermittently reverses its rotational direction in two-dimensional turbulent convection. In this paper, direct numerical simulations of the intermittent reversals of the LSC in a two-dimensional square domain are performed, and the time series of the total angular momentum indicating the rotational direction of the LSC is predicted by reservoir computing whose input consists of the shear rates and temperatures at six locations on the sidewalls. The total angular momentum in the simulation after times shorter than half the typical duration of the quasi-stable states is successfully reproduced by the locally-measurable quantities on the sidewalls because the secondary rolls accompanied by the boundary flow characterize the reversal of the LSC. The successful prediction by such sparse input derived from local measurements on the sidewalls demonstrates that the reservoir computing prediction of the reversal is feasible in laboratory experiments and industrial applications. On the other hand, long-term prediction often provides the total angular momentum opposite in sign to the one in th
The use of the dimensional regularization in the on-mass-shell renormalization scheme sometimes fails to locally cancel the ultraviolet divergence for a class of diagrams in the two-loop order. The mechanism is discussed based on an example with explicit computation.
Self-replicability is the unique attribute observed in all the living organisms and the question how the life was physically initiated could be equivalent to the question how self-replicating informative polymers were formed in the abiotic material world. It has been suggested that the present DNA and proteins world was preceded by RNA world in which genetic information of RNA molecules was replicated by the mutual catalytic function of RNA molecules. However, the important question how the transition occurred from a material world to the very early pre-RNA world remains unsolved experimentally nor theoretically. We present an onset model of mutually catalytic self-replicative systems formed in an assembly of polynucleotides. A quantitative expression of the critical condition for the onset of growing fluctuation towards self-replication in this model is obtained by analytical and numerical calculations.
This paper is intended to survey the basics of localization and anti-localization cardinals on the reals, and its interplay with notions and cardinal characteristics related to measure and category.
We use known finite support iteration techniques to present various examples of models where several cardinal characteristics of Cichoń's diagram are pairwise different. We show some simple examples forcing the left-hand side of Cichoń's diagram, and present the technique of restriction to models to force Cichoń's maximum (original from Goldstern, Kellner, Shelah, and the second author). We focus on how the values forced in all the constellations are obtained via the Tukey order.
A newly developed material can control and "program" heat, allowing it to direct thermal radiation, switch modes, and remember its settings without continuous power。 The innovation could lead to smarter infrared sensors, better energy technologies, and memory devices that use light and heat instead of electrical charges
NASA's Perseverance rover has reached an impressive new milestone on Mars, completing the equivalent of a full marathon by driving 26。2 miles (42。195 kilometers) across the Red Planet
Researchers have achieved a major milestone by creating a long-sought two-dimensional quantum material and confirming its unusual conducting edge states。 The ability to control these states through strain could make the material a promising platform for future room-temperature quantum electronics
Researchers have created self-destructing living plastic that uses engineered bacteria to completely break itself down when activated。 The material degrades in just six days without creating microplastics, offering a potential new solution for single-use plastic waste
Scientists have developed a new framework that could finally apply the laws of thermodynamics to real, ever-changing black holes instead of only perfectly stable ones。 The advance may improve our understanding of black hole mergers, evaporation, and the powerful gravitational wave events detected by observatories like LIGO
Researchers discovered that electricity can dramatically reshape how heat flows through certain ceramic materials, increasing heat conduction by almost threefold in a preferred direction。 The unexpected result could lead to much more efficient cooling technologies and energy-saving devices
The asteroid that wiped out the dinosaurs was likely an exceptionally rare CO chondrite from a distant region of the solar system。 Its unusual chemistry suggests that planet-cooling dust and debris, rather than sulfur inside the asteroid, may have delivered the deadliest blow
Desktops, laptops, phones, CPUs, GPUs, NAS—if you know this stuff, come work for us
Astronomers have uncovered 31 of the oldest known quasars, including the two earliest ever detected, shining from a time when the universe was only about 670 million years old。 Powered by supermassive black holes billions of times the Sun’s mass, these incredibly bright objects challenge scientists’ understanding of how such enormous black holes fo