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1. chinaXiv:202009.00053 [pdf]
A study of a scalar field probes micro space-time
Jian-Bo Deng; Miao-Yi Deng; Qi-Qi FanSubjects: Physics >> The Physics of Elementary Particles and Fields
| In this work, we try to find a way to describe the physical law of micro-world under the frame of a space-time theory. By introducing a scalar field D(x), we rewrite the action of conventional field theory and the Lagrangian describing the motion of the particle, where a modified space-time relation is obtained. To prove the correctness of this attempt, we derive the Klein-Gordon equation by the Hamilton-Jacobi method in four dimensional form. |
2. chinaXiv:201910.00072 [pdf]
段德龙Subjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc.
| [目的]分析解决不确定性原理及量子理论在物理诠释方面的分歧。 [方法]对海森堡不确定性原理数学关系式的原始推导、物理涵义进行了重新检视，并考察了不同作用图景下该关系式的极限。 [结果]在电磁作用图景下，通过对量子力学量的统计分布及其全概率空间的分析，获得了非统计诠释下的不确定性关系式被破坏的结果；利用傅里叶变换，导出了虚拟作用图景下相应共轭力学量的标准差约束关系式；通过对电磁作用图景、引力作用图景以及虚拟作用图景所构成集合的考察，获得了微观量子客体力学状态的确定性判则。 [局限]未分析纠缠。 [结论]①非统计诠释存在逻辑矛盾，不确定性关系、现行量子力学理论仅在统计诠释下，才能对微观量子客体在电磁作用图景中的力学状态作出恰当的描述；② 确定性判则显示，微观粒子的力学状态具有客观确定性，其波函数是对电磁作用图景下的微观粒子力学状态统计呈现相的表述；量子力学非统计诠释所指称的个体几率性实质是微观粒子与作用图景之间互作用统计呈现相的概率反映。 |
submitted time 2020-09-14 Hits12779， Downloads973， Comment 0
3. chinaXiv:202008.00076 [pdf]
Note on anomalies in field theories
刘昌勇Subjects: Physics >> The Physics of Elementary Particles and Fields
| In this note, we investigate the anomalies in field theories. The results of the anomalies through Feynman diagrams calculation are multi-valued function. These single-valued branches of multi-valued function are related to the bound states of neutral pseudoscalar mesons. Adding these bound state contributions, we obtain a new anomaly free condition that all the external particles are on-shell and find the non-perturbative mass spectrum of neutral pseudoscalar mesons. We also discuss the anomaly in 2 dimensional QFT. |
4. chinaXiv:202009.00012 [pdf]
Shadows of rotating Hayward-de Sitter black holes with astrometric observables
Peng-Zhang He; Qi-Qi Fan; Hao-Ran Zhang; Jian-Bo DengSubjects: Physics >> Geophysics, Astronomy, and Astrophysics
| Motivated by recent work on rotating black hole shadow [Phys. Rev. D101, 084029 (2020)], we investigate the shadow behaviors of rotating Hayward-de Sitter black hole for static observers at a finite distance in terms of astronomical observables. This paper uses the newly introduced distortion parameter in [arXiv:2006.00685] to describe the shadow's shape quantitatively. We show that the spin parameter would distort shadows and the magnetic monopole charge would increase the degree of deformation. At the same time, the distortion could be relieved because of the cosmological constant and the distortion would increase with the distance from the black hole. Besides, the spin parameter, magnetic monopole charge and cosmological constant increase will cause the shadow to shrink. |
5. chinaXiv:202009.00011 [pdf]
The cosmological constant from space-time discreteness
Qi-Qi Fan; Cong Li; Hao-Ran Zhang; Peng-Zhang He,; Jian-Bo DengSubjects: Physics >> The Physics of Elementary Particles and Fields
| We regard the background of space-time as a physical system composed of discrete volume elements at the Planck scale and get the internal energy of space-time by Debye model. A temperature-dependent minimum energy limit of the particles is proposed from the thermal motion part of the internal energy. As decreases of the temperature caused by the expansion of the universe, more and more particles would be "released" because of the change of the energy limit, we regard these new particles as a source of dark energy. The minimum energy limit also leads to a corrected number of particles in universe and a modified conservation equation. According to the modified conservation equation, an effective cosmological constant consistent with its observed value is obtained. |
6. chinaXiv:202008.00089 [pdf]
On the description of particle system motion
吴峰Subjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc.
| Based on the concepts of infinitesimal and super real time-space composed of monads, the equations describing the particle flow are proposed. After the initial conditions are given, the state of the particle system at any time can be obtained by solving these equations. The physical properties of the granular matter, such as the moving velocity, the rotation angle, the angular velocity of rotation, the temperature, the pressure, the density, the mass, etc. at any time and space position are obtained. It is also to obtain that the translational motion is not dependent on rotation motion ofthe particles and can be separately analyzed. For a stationary particle system, theconditions that must be met by the force and force moment on the particles in thesystem are given. On this basis, the properties of the granular matter at rest can befurther explored for. |
7. chinaXiv:202008.00086 [pdf]
刘伟Subjects: Physics >> Condensed Matter: Structural, Mechanical and Thermal Properties
| 实验测量表明体心立方固溶体 约在 2.0 at.% Mn发生相变，但这一相变的机制，相变前后铁锰体系的物理性质变化至今仍不清楚。本文通过密度泛函计算，揭示了这一相变是一种同构相变，并阐明了相变机制和相变前后物理性质的变化。 |
8. chinaXiv:202006.00241 [pdf]
LI Yangyang; CHEN Jiacun; AI Shaoshui; SHI HuiSubjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc.
| Regulation of leaf gas exchange plays an important role in the survival of trees and shrubs under future climate change. However, the responses of leaf water potential and gas exchange of shrubs in semi-arid areas to the precipitation alteration are not clear. Here, we conducted a manipulated experiment with three levels of precipitation, i.e., a control with ambient precipitation, 50% above ambient precipitation (irrigation treatment), and 50% below ambient precipitation (drought treatment), with two common shrubs, Salix psammophila C. Wang & C. Y. Yang (isohydric plant, maintaining a constant leaf water potential by stomatal regulation) and Caragana korshinskii Kom. (anisohydric plant, having more variable leaf water potential), on the Chinese Loess Plateau in 2014 and 2015. We measured the seasonal variations of predawn and midday leaf water potential (?pd and ?md), two parameters of gas exchange, i.e., light-saturated assimilation (An) and stomatal conductance (gs), and other foliar and canopy traits. The isohydric S. psammophila had a similar An and a higher gs than the anisohydric C. korshinskii under drought treatment in 2015, inconsistent with the view that photosynthetic capacity of anisohydric plants is higher than isohydric plants under severe drought. The two shrubs differently responded to precipitation manipulation. ?pd, An and gs were higher under irrigation treatment than control for S. psammophila, and these three variables and ?md were significantly higher under irrigation treatment and lower under drought treatment than control for C. korshinskii. Leaf water potential and gas exchange responded to manipulated precipitation more strongly for C. korshinskii than for S. psammophila. However, precipitation manipulation did not alter the sensitivity of leaf gas exchange to vapor-pressure deficit and soil moisture in these two shrubs. Acclimation to long-term changes in soil moisture in these two shrubs was primarily attributed to the changes in leaf or canopy structure rather than leaf gas exchange. These findings will be useful for modeling canopy water-carbon exchange and elucidating the adaptive strategies of these two shrubs to future changes in precipitation. |
submitted time 2020-06-22 From cooperative journals:《Journal of Arid Land》 Hits4490， Downloads276， Comment 0
9. chinaXiv:202006.00200 [pdf]
史志强Subjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc.
| 本文是对《中国科学》一个编者按的商榷和讨论。文章指出手性是手性对称性的破缺，并举例说明了手性对称性和手性的本质区别。手性化合物的一对对映体有不同的生物活性和药物活性，这决不是个别极端的例子，而是非常普遍存在的。生物体内参与蛋白质组成的氨基酸是手性的，但它们既不全都是左旋的，也不全都是右旋的，只能说它们全部都是L构型的。蛋白质的结构是复杂的，我们不能笼统地说蛋白质是右旋的，只能说蛋白质二级结构中的α-螺旋结构是右旋的。最后，我们分析了对手性定义的几种错误表述，并指出产生这些错误的原因。 |
10. chinaXiv:202007.00012 [pdf]
史志强Subjects: Physics >> Interdisciplinary Physics and Related Areas of Science and Technology
| 手性对称性与手性是两个不同的概念，前者研究对称性，后者是手性不对称的简称，它研究对称性的破缺。我们关注手性实际上是研究自然界的手性不对称性，而不是手性对称性。手性可分为结构手性和功能手性两种。结构手性是“互为镜像”的两个物体在自然界存在的数量不同，它强调的是几何结构，手形手性、螺旋手性和旋转手性都是结构手性。功能手性强调的是功能，即它们的几何结构或者坐标系是手性对称的，但其功能（物理性质、化学性质、数学意义、生物活性、药物活性、生物的行为和习性等）不是“互为镜像”的。功能手性是结构手性的拓展，它使手性的表现形式更为多样化。手性分子绝大多数是一种功能手性分子。 |
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