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Quantum Unruh Effect on Radiation of Black Holes
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作者 Tianxi Zhang 《Journal of Modern Physics》 2024年第6期938-949,共12页
The quantum Unruh effect on radiation of a gravitational object including a black hole is analyzed and calculated. It is surprisingly found that the well-known Hawking radiation of a black hole is not physical. Applyi... The quantum Unruh effect on radiation of a gravitational object including a black hole is analyzed and calculated. It is surprisingly found that the well-known Hawking radiation of a black hole is not physical. Applying the Stephan-Boltzmann law with the use of the Unruh radiation temperature at the surface of a black hole to calculate the power of radiation of the black hole is conceptually unphysical. This is because the Unruh radiation temperature results from the gravitational field of the object rather than from the thermal motion of matter of the object, so that the Stephan-Boltzmann law is not applicable. This paper shows that the emission power of Unruh radiation from a gravitational object should be calculated in terms of the rate of increase of the total Unruh radiation energy outside the object. The result obtained from this study indicates that a gravitational object can emit Unruh radiation when the variation of its mass and radius satisfies an inequality of dM/M > 1.25dR/R. For a black hole, the emission of Unruh radiation does not occur unless it can loose its mass (dM < 0). The emission power of Unruh radiation is only an extremely tiny part of the rate of mass-energy loss if the black hole is not extremely micro-sized. This study turns down our traditional understanding of the Hawking radiation and thermodynamics of black holes. 展开更多
关键词 Black Hole GRAVITATION Quantum Field Theory blackbody radiation
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Analysis of the blackbody-radiation shift in an ytterbium optical lattice clock
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作者 徐艺琳 徐信业 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第10期119-127,共9页
We accurately evaluate the blackbody-radiation shift in a171 Yb optical lattice clock by utilizing temperature measurement and numerical simulation. In this work. three main radiation sources are considered for the bl... We accurately evaluate the blackbody-radiation shift in a171 Yb optical lattice clock by utilizing temperature measurement and numerical simulation. In this work. three main radiation sources are considered for the blackbody-radiation shift, including the heated atomic oven, the warm vacuum chamber, and the room-temperature vacuum windows. The temperatures on the outer surface of the vacuum chamber are measured during the clock operation period by utilizing seven calibrated temperature sensors. Then we infer the temperature distribution inside the vacuum chamber by numerical simulation according to the measured temperatures. Furthermore, we simulate the temperature variation around the cold atoms while the environmental temperature is fluctuating. Finally, we obtain that the total blackbody-radiation shift is -1.289(7)Hz with an uncertainty of 1.25×10;for our;Yb optical lattice clock. The presented method is quite suitable for accurately evaluating the blackbody-radiation shift of the optical lattice clock in the case of lacking the sensors inside the vacuum chamber. 展开更多
关键词 optical lattices blackbody radiation shift temperature measurement finite element analysis
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The Origin of Cosmic Microwave Background Radiation
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作者 Zhenglong Xu 《Journal of Modern Physics》 CAS 2023年第4期534-551,共18页
This paper explains the Olbers paradox and the origin of cosmic microwave background radiation (CMBR) from the viewpoint of the quantum redshift effect. The derived formula dispels the Olbers paradox, confirming that ... This paper explains the Olbers paradox and the origin of cosmic microwave background radiation (CMBR) from the viewpoint of the quantum redshift effect. The derived formula dispels the Olbers paradox, confirming that the CMBR originates from the superposition of light radiated by stars in the whole universe, not the relic of the Big Bang. The dark-night sky and CMBR are all caused by Hubble redshift—the physical mechanism is the quantum redshift of the photon rather than cosmic expansion. So this theory supports the infinite and steady cosmology. 展开更多
关键词 Olbers Paradox Cosmic Microwave Background radiation (CMBR) Big Bang Theory Hubble Redshift Quantum Redshift Effect of Photon Stefan-Boltzmann Law blackbody radiation
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Quantum Unruh Effect on Singularities of Black Holes
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作者 Tianxi Zhang 《Journal of Modern Physics》 2023年第11期1526-1536,共11页
It is generally believed that matter inside or once entering a black hole will gravitationally fall into the center and form a size-less singularity, where the density goes to infinity and the spacetime breaks down wi... It is generally believed that matter inside or once entering a black hole will gravitationally fall into the center and form a size-less singularity, where the density goes to infinity and the spacetime breaks down with infinite curvature or gravitation. In accordance to the Unruh effect, one of the most surprizing predictions of quantum field theory, however, it is found from this study that such singularity cannot be actually formed because it violates the law of energy conservation. The total Unruh radiation energy of the size-less singularity is shown to be infinite, much greater than that the collapsing matter can generate. All the energies of the collapsing matter including the gravitational potential energy, deducted, are far below the Unruh radiation energy, increased, for the collapsing matter to form the singularity. The collapsing matter actually formed is shown to be not a size-less singular point but a small sphere with a finite radius, which is found to be dependent of the mass of the singularity sphere, approximately proportional to the square root of the mass. The radius of the singularity sphere cannot be zero, unless the mass also approaches to zero. The result obtained from this study not only provides us a quantum solution to the problem of black hole singularity, but also leads to profound implications to the spacetime and cosmology. The Unruh effect excludes a black hole to form a size-less singularity, which has a finite mass but infinite density, curvature, and Unruh radiation energy. A point-like or size-less singularity can only be massless and naked. 展开更多
关键词 Black Hole SINGULARITY GRAVITATION Quantum Field Theory blackbody radiation
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Calculations of atomic polarizability for beryllium using MCDHF method
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作者 董辉 蒋军 +2 位作者 武中文 董晨钟 Gediminas Gaigalas 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第4期211-215,共5页
Based on the fully relativistic multiconfiguration Dirac-Hartree-Fock(MCDHF)method and the corresponding program package GRASP2018,a new program for calculating the polarizabilities is developed.As the first applicati... Based on the fully relativistic multiconfiguration Dirac-Hartree-Fock(MCDHF)method and the corresponding program package GRASP2018,a new program for calculating the polarizabilities is developed.As the first application,the static electric-dipole polarizabilities of the ground state 2s^(2)^(1)S_(0) and excited state 2s2p^(3)P_(0) of beryllium are calculated.By means of these polarizabilities,the blackbody radiation(BBR)shift of the 2s2p^(3)P_(0)→2s^(2)^(1)S_(0)clock transition is determined.The present results agree very well with other available theoretical results. 展开更多
关键词 POLARIZABILITIES MCDHF blackbody radiation shift
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The Principles of Causal Conspiracy
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作者 Michael M.Anthony 《Journal of Quantum Information Science》 2014年第3期137-172,共36页
The human mind understands logical processes and causality and formulates theories based on logical descriptions of empirical evidence. The Principles of Causal Conspiracy is based on defining information as logical c... The human mind understands logical processes and causality and formulates theories based on logical descriptions of empirical evidence. The Principles of Causal Conspiracy is based on defining information as logical charges similar to electric charges. Such information charges can be modeled in the vacuum of a quantum probability firmament as symmetry of quantum charges with a zero net charge. Observation of a state lifts one of these charges in a M&oumlbius transformation from a multipolar field of possibilities that maximizes a local monopole field that is observable. In the first of several papers, I introduce new and profound principles, the Principles of Causal Conspiracy, to provide a consistent epistemology for quantum theory, relativity theory and all the known sciences. 展开更多
关键词 Special Relativity Theory Dipole MONOPOLES Quantum Theory QUARKS Space Time Moments Big Bang MOND ANNIHILATORS Creators Fields Charges Logic MOBIUS Lagrangian Blackholes Riemann Sphere Causality Uncertainty blackbody radiation 8-Fold Way
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Broadband terahertz radiation from a biased two-dimensional electron gas in an AlGaN/GaN heterostructure
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作者 郑中信 孙建东 +2 位作者 周宇 张志鹏 秦华 《Journal of Semiconductors》 EI CAS CSCD 2015年第10期55-59,共5页
The broadband terahertz (THz) emission from drifting two-dimensional electron gas (2DEG) in an AI- GaN/GaN heterostructure at 6 K is reported. The devices are designed as THz plasmon emitters according to the Smit... The broadband terahertz (THz) emission from drifting two-dimensional electron gas (2DEG) in an AI- GaN/GaN heterostructure at 6 K is reported. The devices are designed as THz plasmon emitters according to the Smith-Purcell effect and the 'shallow water' plasma instability mechanism in 2DEG. Plasmon excitation is excluded since no signature of electron-density dependent plasmon mode is observed. Instead, the observed THz emission is found to come from the heated lattice and/or the hot electrons. Simulated emission spectra of hot electrons taking into account the THz absorption in air and Fabry-Pérot interference agree well with the experiment. It is confirmed that a blackbody-like THz emission will inevitably be encountered in similar devices driven by a strong in-plane electric field. A conclusion is drawn that a more elaborate device design is required to achieve efficient plasmon excitation and THz emission. 展开更多
关键词 two-dimensional electron gas hot electron blackbody radiation PLASMON Fabry-Pérot cavity
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TBB-REVEALED ANNUAL CYCLE FEATURES OF TROPICAL LFO 被引量:1
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作者 智协飞 陈旭红 田华 《Acta meteorologica Sinica》 SCIE 1997年第4期460-468,共9页
In the context of 1980—1992 JMA(Japan Meteorological Agency)GMS TBB gridded dataset, study is undertaken of annual cycle features of FFT-derived window power spectrum averaged over the record length,with localized sp... In the context of 1980—1992 JMA(Japan Meteorological Agency)GMS TBB gridded dataset, study is undertaken of annual cycle features of FFT-derived window power spectrum averaged over the record length,with localized space/time characteristics of low-frequency oscillation(LFO)in the tropical atmosphere investigated alongside possible causes.It turns out that the LFO takes on surprisingly noticeable annual cycle features marked by a wider variable range of the LFO periods over northern tropics than the southern counterpart and equatorial vicinity.In addition,on the whole,the signals are more intense in the Northern Hemisphere during summer/autumn and at equatorial/southern latitudes when northern winter/spring occur as well.Also,not all these features are identical for different segments at the same latitudes,displaying signatures on a local basis,and the spatial/temporal locality can be qualitatively interpreted in terms of nonlinear interaction between tropical waves,and modulation of diabatic heating on the LFO periods. 展开更多
关键词 TBB(cloud-top blackbody radiation temperature) low frequency oscillaton (LFO) annual cycle feature
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