分类: 物理学 >> 普通物理:统计和量子力学,量子信息等 提交时间: 2021-02-10
摘要: Partial entropy entanglement is a very popular method to measure the entanglement of quantum systems, which is based on the classic von Neumann entropy. However, because of the problem of classical von Neumann entropy in measuring the uncertainty of quantum systems, the partial entropy entanglement is not efficient enough to measure the entanglement of quantum systems. The new entropy measure of quantum uncertainty is a model for measuring the uncertainty of a quantum system based on the classic von Neumann entropy and belief entropy, which has higher performance than the classic von Neumann entropy in measuring the uncertainty entropy of a quantum system.Based on the new entropy measure of quantum uncertainty and the classic partial entropy entanglement, this paper proposes a new model to measure the quantum entanglement measurement, named quantum entanglement measurement based on belief entropy. When the new entropy measure of quantum uncertainty degenerates to classical von Neumann entropy, the quantum entanglement measurement based on belief entropy will degenerate to classical partial entropy entanglement. Numerical examples are used to prove that quantum entanglement measurement based on belief entropy is more efficient and reliable in measuring the entanglement of quantum systems than the classic partial entropy entanglement. The experimental results show that the quantum entanglement measurement based on belief entropy can measure the uncertainty of quantum systems more efficiently and reliably than the classical classic partial entropy entanglement.
分类: 计算机科学 >> 计算机科学技术其他学科 提交时间: 2021-06-03
摘要: Complex evidence theory has been applied to several fields due to its advantages in modeling and processing uncertain information. However,to measure the uncertainty of the complex mass function is still an open issue. The main contribution of this paper is to propose a complex-valued Deng entropy. The complex-valued Deng entropy can effectively measure the uncertainty of the mass function in the complex-valued framework. Meanwhile, the complex-valued Deng entropy is a generalization of the Deng entropy and Shannon entropy. That is, the complex-valued Deng entropy can degenerate to classical Deng entropy when the complex-valued mass function degenerates to a mass function in real space. In addition, the proposed complex-valued Deng entropy can also degenerates to Shannon entropy when the complex-valued mass function degenerates to a probability distribution in real space. Some numerical examples demonstrate the compatibility and effectiveness of the complex-valued Deng entropy.
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等 提交时间: 2021-02-04
摘要: Quantum theory is currently the most important research field. Before processing the information of a quantum system, we must first understand how to measure the uncertainty of a quantum system. Von Neumann entropy is a very classic method to measure the uncertainty of quantum systems. However, due to the particularity of quantum systems, it is very difficult to measure the uncertainty of quantum systems, so that the measurement efficiency of the classical von Neumann entropy is not high in some cases. Based on the classic von Neumann entropy and belief entropy, this paper proposes a new entropy model to measure the uncertainty of quantum systems, which can use fully the eigenvalues and eigenvectors of the density matrix of quantum systems, and give the uncertainty of the quantum system. Some numerical examples are used to prove that the proposed entropy is more efficient and reliable in measuring quantum systems than the classical von Neumann entropy. The experimental results show that the proposed entropy can measure the uncertainty of quantum systems more efficiently and reliably than the classical von Neumann entropy.
分类: 物理学 >> 核物理学 提交时间: 2016-09-06
摘要: We investigate the short interval expansion of the R\'enyi entropy for two-dimensional conformal field theory (CFT) on a torus. We require the length of the interval ℓ to be small with respect to the spatial and temporal sizes of the torus. The operator product expansion of the twist operators allows us to compute the short interval expansion of the R\'enyi entropy at any temperature. In particular, we pay special attention to the large c CFTs dual to the AdS3 gravity and its cousins. At both low and high temperature limits, we read the R\'enyi entropies to order ℓ6, and find good agreements with holographic results. Moreover, the expansion allows us to read 1/c contribution, which is hard to get by expanding the thermal density matrix. We generalize the study to the case with the chemical potential as well.
分类: 计算机科学 >> 计算机科学技术其他学科 提交时间: 2021-05-31
摘要: Complex-valued expression models have been widely used in the application of intelligent decision systems. However, there is a lack of entropy to measure the uncertain information of the complex-valued probability distribution. Therefore, how to reasonably measure the uncertain information of the complex-valued probability distribution is a gap to be filled. In this paper, inspired by the Renyi entropy, we propose the Complex-valued Renyi entropy, which can measure uncertain information of the complex-valued probability distribution under the framework of complex numbers, and is also the first time to measure uncertain information in the complex space. The Complex-valued Renyi entropy contains the features of the classical Renyi entropy, i.e., the Complex-valued Renyi Entropy corresponds to different information functions with different parameters q. Meanwhile, the Complex-valued Renyi entropy has some properties, such as non-negativity, monotonicity, etc. Some numerical examples can demonstrate the flexibilities and reasonableness of the Complex-valued Renyi entropy.
分类: 物理学 >> 凝聚态:电子结构、电、磁和光学性质 提交时间: 2017-11-27
摘要: Cubic helimagnet FeGe has emerged as a class of skyrmion materials near room temperature that may impact future information technology. Experimentally identifying the detailed properties of skyrmion materials enables their practical application acceleratedly. Here we study the magnetic entropy change (MEC) of single crystalline FeGe in its precursor region and clarify its close relation to the critical exponents of a second-order phase transition in this area. The maximum MEC is found to be 2.86 J/kg.K for 7.0 T magnetic field change smaller than that of common magnetocaloric materials indicating the multiplicity and complexity of the magnetic structure phases in the precursor region. This result also implies that the competition among the multimagnetic phases can partly counteract the magnetic field driven force and establishes a stable balance. Based on the obtained MEC and the critical exponents, the exact Curie temperature of single crystalline FeGe under zero magnetic field is confirmed to be 279.1 K, higher than previously reported 278.2 K. This finding pave the way for reconstruction of FeGe phase diagram in the precursor region.
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等 提交时间: 2023-05-20
摘要: By using an integral formula, we easily calculated the von Neumann entropy of any quantum state.
提交时间: 2017-04-06
摘要: By direct measurements, the elastocaloric effect at various temperatures in a [001)-oriented Ni45.7Mn36.6In13.3Co5.1 metamagnetic shape memory polycrystal has been investigated. A reversible temperature change of +/-3.5 K, due to the relatively low stress
分类: 物理学 >> 凝聚态:结构、力学和热性能 提交时间: 2017-01-10
摘要: We argue microscopically that helium-4 superflows carry heat unavoidably. We then show that a heterogeneous helium-4 superflow loop can be used to realize an entropy-decreasing process, thus providing an exception to the second law of thermodynamics. This exception is a quantum effect for its essential dependence on the quantum phenomenon of superfluidity.
分类: 物理学 >> 凝聚态:电子结构、电、磁和光学性质 提交时间: 2016-09-21
摘要: We review on a recently proposed quantum exception to the second law of thermodynamics. We emphase that helium-4 superflows, like any other forms of flows, shall carry entropy or heat in a thermal environment. Following that, one can use a heterogeneous helium-4 superflow loop to realize entropy-decreasing processes. We also mention that the heat content of a superflow has an unusual dependence on flow velocity, which is an important factor contributing to the entropy-decreasing processes.
分类: 物理学 >> 基本粒子与场物理学 提交时间: 2016-05-08
摘要: We study the P - V criticality and phase transition in the extended phase space of charged Gauss-Bonnet black holes in anti-de Sitter space, where the cosmological constant. appears as a dynamical pressure of the system and its conjugate quantity is the thermodynamic volume of the black holes. The black holes can have a Ricci flat (k - 0), spherical (k = 1), or hyperbolic (k = -1) horizon. We find that for the Ricci flat and hyperbolic Gauss-Bonnet black holes, no P - V criticality and phase transition appear, while for the black holes with a. spherical horizon, even when the charge of the black hole is absent, the P - V criticality and the small black hole/large black hole phase transition will appear, but it happens only in d = 5 dimensions; when the charge does not vanish, the P - V criticality and the small black hole/large phase transition always appear in d = 5 dimensions; in the case of d >= 6, to have the P - V criticality and the small black hole/large black hole phase transition, there exists an upper bound for the parameter b = (alpha) over tilde vertical bar Q vertical bar(-2/(d-3)), where (alpha) over tilde is the Gauss-Bonnet coefficient and Q is the charge of the black hole. We calculate the critical exponents at the critical point and find that for all cases, they are the same as those in the van der Waals liquid-gas system.
分类: 数学 >> 统计和概率 提交时间: 2024-02-04
摘要: The three frameworks for theories of consciousness taken most seriously by neuroscientists are that consciousness is a biological state of the brain,the global workspace perspective,and the perspective of higher state.Consciousness is discussed from viewpoint of theory of Entropypartition of complex system in present article. Human brains system self-organizably andadaptively implements partition 、 aggregation and integration, and consciousness emerges.The Gibss representation of consciousness is proved and That consciousness originates from quantum mechanical processes of brain activity is explained by means of SW entropy
分类: 物理学 >> 凝聚态:电子结构、电、磁和光学性质 分类: 物理学 >> 普通物理:统计和量子力学,量子信息等 提交时间: 2020-12-12
摘要: We observed a counter-intuitive remarkable heating phenomenon generated by helium-4 superflows. This phenomenon establishes that superflows carry thermal energies and entropies, which is in contrast to the hypothesis of the two-fluid model. Quantum many-body theory of superfluids provides a natural understanding of the phenomenon.
分类: 物理学 >> 凝聚态:电子结构、电、磁和光学性质 提交时间: 2017-11-27
摘要: The B20 compound MnSi exhibits a skyrmion phase in a certain range of temperature (T) and external magnetic ¯eld (H) in addition to the helimagnetic ordering. In this work, the magnetic entropy change (¢SM) in the single crystal helimagnet MnSi has been investigated by the scaling analysis. The ¢SM(T;H) curves in higher ¯eld range (2 kOe < H < 5.6 kOe) collapse onto an universal curve after scaling, which is independent of T and H. Based on this universal curve, the ¢SM(T;H) (excluding the skyrmion entropy change) at any T and H can be calculated. On the other hand, a small valley is found on the ¢SM(T) curve at » 28.5 K in the ¯eld range from » 1 kOe to » 2 kOe, which is resulted from the skyrmion phase. Subsequently, the magnetic entropy change of the skyrmion phase [¢SskX M (T;H)] can be derived by subtraction of the calculated ¢Scal M (T;H) from the experimental ¢Sexp M (T;H). The obtained results show that ¢SskX M reaches the maximum at » 1.6 kOe, which indicates the highest number of skyrmion vortices at that ¯eld.
分类: 地球科学 >> 空间物理学 提交时间: 2017-03-10
摘要: In PolSAR data processing, deorientation operation is often necessary. The existing deorientation method uniformly deorients all the sub-scatterers of a resolution cell with one orientation angle. For high entropy situation, the sub-scatterers have diverse OAs, and the effect of the existing method is unsatisfactory. A novel deorientation method is proposed to well treat the high entropy situation. Cloude's eigen-decomposition to the coherency matrix is first carried out. The three eigenvectors are then separately deoriented with their own orientation angles. Experiments demonstrate that the proposed method is suitable for extraction of urban regions, especially for extraction of oriented urban regions. �VDE VERLAG GMBH �Berlin �Offenbach.
分类: 物理学 >> 凝聚态:结构、力学和热性能 提交时间: 2017-01-23
摘要: In this note, we point out that a case of mechano-caloric effect of superfluid $^4$He actually establishes a temporary entropy-decreasing process, which was unnoticed in the past. We show that this process can be used to convert thermal energy from the environment to useful energy in principle, and therefore, the second law of thermodynamics is not an universal law.
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等 提交时间: 2021-03-23
摘要: In real life, occurrences of a series of things are supposed to come in an order. Therefore, it is necessary to regard sequence as a crucial factor in managing different kinds of things in fuzzy environment. However, few related researches have been made to provided a reasonable solution to this demand. Therefore, how to measure degree of uncertainty of ordinal fuzzy sets is still an open issue. To address this issue, a novel ordinal relative fuzzy entropy is proposed in this paper taking orders of propositions into consideration in measuring level of uncertainty in fuzzy environment. Compared with previously proposed entropies, effects on degrees of fuzzy uncertainty brought by sequences of sequential propositions are embodied in values of measurement using proposed method in this article. Moreover, some numerical examples are offered to verify the correctness and validity of the proposed entropy.
分类: 物理学 >> 核物理学 提交时间: 2023-06-18 合作期刊: 《Nuclear Science and Techniques》
摘要: The nuclear level density and entropy were calculated for 105Cd, 106Cd, 111Cd and 112Cd based on the Back Shifted Fermi Gas (BSFG) model and the Constant Temperature (CT) model. Then, the entropies were extracted in the microcanonical ensemble according to recent experimental data on nuclear level density measured by the Oslo group for these nuclei and are compared with their corresponding macroscopic calculations. Entropies of the neutron hole were estimated from the entropy difference between the odd-mass and even-even nuclei. The results reveal that the CT model describes better the extracted microcanonical results.
分类: 管理学 >> 管理学其他学科 提交时间: 2022-11-23 合作期刊: 《2022年第三届传播、创新和经济管理国际研讨会》
摘要: In recent years, the video characteristics of mainstream media news communication methods have become prominent. Among them, graphic short video news composed of images, words and audio has become the main force of short video news communication. This study preliminarily discusses the impact of graphic short video on information entropy reduction and communication effect by using the methods of questionnaire and in-depth interview. The study found that the font size, color , news background and music score of text in video news will affect the communication effect of news.
分类: 机械工程 >> 机械制造自动化 提交时间: 2022-10-21
摘要: With growing interest in Laser Additive Manufacturing (LAM) of High-entropy alloys (HEAs) during most recent years, compositional elements design and process strategies innovation are primary methods to overcome undesirable microstructures and defects. Here we propose a new approach, a novel real-time laser shock modulation of melt pool (LSMMP) to obtain melt pool modifications for yielding HEAs with desired characteristics. LSMMP utilizes a pulsed laser shocking a liquid melt pool caused by a continuous wave laser, enabling non-destructive and real-time modulations for high-performance HEAs. The numerical simulation reveals the convection mechanism of the melt pool in the LSMMP process, and the intervention of the pulsed laser promotes melt pool flow type to convert the Marangoni effect into a multi-convective ring, which accelerates melt pool flow and inhibits columnar crystal growth. Experimental results show the evolution law of the microstructure in the LSMMP process. The microstructure of CrFeCoNi HEAs undergoes a Columnar-Equiaxed Transition (CET), and higher hardness is obtained. Laser shock is demonstrated to be an effective in-situ modulative tool for controlled additive manufacturing.