Results 41 to 50 of about 7,476 (217)

Cosmology Is Not a Renormalization Group Flow [PDF]

Physical Review Letters, 2008
A critical examination is made of two simple implementations of the idea that cosmology can be viewed as a renormalization group flow. Both implementations are shown to fail when applied to a massless, minimally coupled scalar with a quartic self-interaction on a locally de Sitter background. Cosmological evolution in this model is not driven by any RG
openaire   +4 more sources

Fundamentals of Thermal Transport and Energy Conversion in Ultra‐High Temperature Ceramics: From Microscale Mechanisms to Macroscopic Properties

Advanced Science, EarlyView.
This review critically examines thermal transport and radiative properties of ultra‐high temperature ceramics for hypersonic flight, advanced nuclear systems, and next‐generation energy conversion devices. It explores phonon–photon–electron interactions, microstructural engineering, thermoelectric conversion, and machine learning‐accelerated multiscale
Zhipeng Pei, Yue Li, Jiayu Xing, Yue Zhu, Ru Zhang, Huan Wu, Zihao Qin, Gang Pei, Man Li   +8 more
wiley   +1 more source

Flexoelectricity in Photoconversion: Fundamentals, Materials, and Outlooks

Advanced Science, EarlyView.
Mechanical bending of a flexible cantilever induces a strain gradient in the photoactive material. The resulting flexoelectric field couples with photovoltaic and photoconductive effects, modulating charge generation, separation, and collection. A comparative analysis of oxide perovskites, halide perovskites, and two‐dimensional materials is presented,
Xiang Huang, Feng Li, Rongkun Zheng
wiley   +1 more source

Asymptotic freedom and higher derivative gauge theories

Journal of High Energy Physics, 2021
The ultraviolet completion of gauge theories by higher derivative terms can dramatically change their behavior at high energies. The requirement of asymptotic freedom imposes very stringent constraints that are only satisfied by a small family of higher ...
M. Asorey, F. Falceto, L. Rachwał
doaj   +1 more source

Tailored D‐π Conjugation Boosts Piezocatalytic CO2 Reduction in a Platinum(II)‐Acetylide Framework

Advanced Science, EarlyView.
The highly conjugated metalII‐acetylide framework demonstrates efficient ultrasound‐driven conversion of CO2 to CO. The piezoelectric field generated by ultrasound facilitates electron transfer from the tetraphenylene π‐column to the MII‐bis(acetylide) moiety, enabling CO2 activation. Compared to PdII‐ and NiII‐based analogues, the stronger d–π orbital
Mude Zhu, Yingtang Zhou, Kai Wang, Xiaoyun Fan, Yang Ding, Wai‐Yeung Wong, Linli Xu   +6 more
wiley   +1 more source

Renormalization scheme dependence with renormalization group summation [PDF]

Physical Review D, 2015
We consider all radiative corrections to the total electron-positron cross section showing how the renormalization group equation can be used to sum the logarithmic contributions in two ways. First of all, one can sum leading-log etc. contributions. A second summation shows how all logarithmic corrections can be expressed in terms of log-independent ...
openaire   +2 more sources

Large Temperature‐invariant Anomalous Nernst Effect in Non‐collinear Antiferromagnet Mn3Pt

Advanced Science, EarlyView.
Based on the noncollinear antiferromagnetic Mn3Pt thin films, the composition‐tunable Mn‐3d orbital states directly govern the Berry curvature. As a result, a giant and temperature‐invariant anomalous Nernst coefficient of 0.71 µV/K is achieved under Mn‐rich conditions.
Pengwei Gong, Xiaolin Zhang, Wei Zhu, Mingzhi Wang, Chang Pan, Aoqi Xu, Yandong Guo, Yuheng Li, Jiaxin Chen, Yanchang Zhou, Zhong Shi, Dingfu Shao, Liang Liu, Shiming Zhou, Yicheng Guan, Ruiqing Cheng, Xuepeng Qiu   +16 more
wiley   +1 more source

Accurately Deciphering Tissue Heterogeneity From Spatial Multi‐Modal and Multi‐Omics With STransformer

Advanced Science, EarlyView.
STransformer is a unified deep learning framework designed to seamlessly accommodate a comprehensive landscape of spatial data. By simultaneously capturing short‐range cellular interactions and tissue‐wide semantic patterns, it extracts robust representations to accurately dissect complex tissue heterogeneity.
Xingyi Li, Jialuo Xu, Gaoyuan Du, Xiangting Jia, Dongmin Zhao, Chunyan Zhou, Kexin Xiao, Jia Gu, Junnan Zhu, Xuequn Shang   +9 more
wiley   +1 more source

Nested Selves: Self‐Organization and Shared Markov Blankets in Prenatal Development in Humans

Topics in Cognitive Science, EarlyView., 2023
Abstract The immune system is a central component of organismic function in humans. This paper addresses self‐organization of biological systems in relation to—and nested within—other biological systems in pregnancy. Pregnancy constitutes a fundamental state for human embodiment and a key step in the evolution and conservation of our species. While not
Anna Ciaunica, Michael Levin, Fernando E. Rosas, Karl Friston   +3 more
wiley   +1 more source

Renormalization group approach to confinement

European Physical Journal C: Particles and Fields
While we have several complementary models of confinement, some of which are phenomenologically appealing, we do not have the ability to calculate analytically even simple aspects of confinement, let alone have a framework to eventually prove confinement.
Gerrit Schierholz
doaj   +1 more source