In our recent papers, we have identified a class of phase transitions in the market-directed resource- allocation game, and found that there exists a critical point at which the phase transitions occur. The critical p...In our recent papers, we have identified a class of phase transitions in the market-directed resource- allocation game, and found that there exists a critical point at which the phase transitions occur. The critical point is given by a certain resource ratio. Here, by performing computer simulations and theoretical analysis, we report that the critical point is robust against various kinds of human hedge behavior where the numbers of herds and contrarians can be varied widely. This means that the critical point can be independent of the total number of participants composed of normal agents, herds and contrarians, under some conditions. This finding means that the critical points we identified in this complex adaptive system (with adaptive agents) may also be an intensive quantity, similar to those revealed in traditional physical systems (with non-adaptive units).展开更多
Phase transitions are being used increasingly to probe the collective behaviors of social human systems. In this study, we propose a different way of investigating such transitions in a human system by establishing a ...Phase transitions are being used increasingly to probe the collective behaviors of social human systems. In this study, we propose a different way of investigating such transitions in a human system by establishing a two-sided minority game model. A new type of agents who can actively transfer resources are added to our artificial bipartite resource-allocation market. The degree of deviation from equilibria is characterized by the entropy-like quantity of market complexity. Under different threshold values, Qth, two phases are found by calculating the exponents of the associated power spectra. For large values of Qth, the general motion of strategies for the agents is relatively periodic whereas for low values of Qth, the motion becomes chaotic. The transition occurs abruptly at a critical value of Qty. Our simulation results were also tested based on human experiments. The results of this study suggest that a chaotic-periodic transition related to the quantity of market information should exist in most bipartite markets, thereby allowing better control of such a transi- tion and providing a better understanding of the endogenous emergence of business cycles from the perspective of quantum mechanics.展开更多
In the past two decades, statistical physics was brought into the field of finance, applying new methods and concepts to financial time series and developing a new interdiscipline "econophysics". In this review, we ...In the past two decades, statistical physics was brought into the field of finance, applying new methods and concepts to financial time series and developing a new interdiscipline "econophysics". In this review, we introduce several commonly used methods for stock time series in econophysics including distribution functions, correlation functions, detrended fluctuation analysis method, de- trended moving average method, and multifractal analysis. Then based on these methods, we review some statistical properties of Chinese stock markets including scaling behavior, long-term correla- tions, cross-correlations, leverage effects, antileverage effects, and multifractality. Last, based on an agent-based model, we develop a new option pricing model -- financial market model that shows a good agreement with the prices using real Shanghai Index data. This review is helpful for people to understand and research statistical physics of financial markets.展开更多
We propose a general method to realize a total scattering of an incident acoustic wave at interfaces between different media while allowing the flow of air, fluids and/or particles. This originates from the enlargemen...We propose a general method to realize a total scattering of an incident acoustic wave at interfaces between different media while allowing the flow of air, fluids and/or particles. This originates from the enlargement of the equivalent acoustic scattering cross section of an embedded object coated with acoustic metamaterials, which causes the coated object to behave as a scatterer bigger than its physical size. We theoretically design a model circular cylindrical object coated with such meta- materials whose properties are determined according to two different, but identical, methods. The desired function is confirmed for both far-field and near-field cases with full wave simulations based on the finite element method. This work reveals a promising way to achieve noise shielding and naval camouflage.展开更多
Agent-based modeling and controlled human experiments serve as two fundamental research methods in the field of econophysics. Agent-based modeling has been in development for over 20 years, but how to design virtual a...Agent-based modeling and controlled human experiments serve as two fundamental research methods in the field of econophysics. Agent-based modeling has been in development for over 20 years, but how to design virtual agents with high levels of human-like "intelligence" remains a challenge. On the other hand, experimental econophysics is an emerging field; however, there is a lack of experience and paradigms related to the field. Here, we review some of the most recent research results obtained through the use of these two methods concerning financial problems such as chaos, leverage, and business cycles. We also review the principles behind assessments of agents' intelligence levels, and some relevant designs for human experiments. The main theme of this review is to show that by combining theory, agent-based modeling, and controlled human experiments, one can garner more reliable and credible results on account of a better verification of theory; accordingly, this way, a wider range of economic and financial problems and phenomena can be studied.展开更多
Confinement can induce unusual behaviors of water. Inspired by the fabrication of carbon nanotubes with noncircular cross sections, we performed molecular dynamics simulations to investigate the mobilities of water co...Confinement can induce unusual behaviors of water. Inspired by the fabrication of carbon nanotubes with noncircular cross sections, we performed molecular dynamics simulations to investigate the mobilities of water confined in carbon nanochannels with circular, square, and equilateral triangular cross sections over a variety of dimensions. We find that water exhibits disparate mobilities across different types of channels below 0.796 nm(2). Notably, compared with the other two channels, water in equilateral triangular channels displays the greatest mobilities. Moreover, at 0.425 nm(2), different ordered structures are found in the three channels, and water inside the square channel exhibits an extremely low mobility. It is also found that above 0.796 nm(2), the mobilities along the tube axis of water converge to that of the bulk. These phenomena are understood by analyzing the structure, dynamics, and hydrogen bonding of water. Our work explores the mobilities of water across noncircular carbon nanochannels, which may expand the prospect of noncircular nanochannels in scientific studies and practical applications, such as desalination and drug delivery.展开更多
The transmission spectra of a TiO2-silicone oil suspension in an increasing external electric field are studied. As the electric field increases, the structure of the suspension changes from a disordered one to an ord...The transmission spectra of a TiO2-silicone oil suspension in an increasing external electric field are studied. As the electric field increases, the structure of the suspension changes from a disordered one to an ordered one. Interestingly, the transmission spectra blueshift in this structure-ordering process. Furthermore, the relative transmission spectra exhibit Fano-like asymmetric line shapes. The deviation ratio of each asymmetric line shape increases monotonously as the disorder of the suspension decreases. We suggest that this blueshift phenomenon can be used to characterize the disorder strength of three- dimensional systems.展开更多
文摘In our recent papers, we have identified a class of phase transitions in the market-directed resource- allocation game, and found that there exists a critical point at which the phase transitions occur. The critical point is given by a certain resource ratio. Here, by performing computer simulations and theoretical analysis, we report that the critical point is robust against various kinds of human hedge behavior where the numbers of herds and contrarians can be varied widely. This means that the critical point can be independent of the total number of participants composed of normal agents, herds and contrarians, under some conditions. This finding means that the critical points we identified in this complex adaptive system (with adaptive agents) may also be an intensive quantity, similar to those revealed in traditional physical systems (with non-adaptive units).
基金We thank Dr. W. Wang for fruitful discussions. We acknowledge financial support from the National Natural Science Foundation of China under Grant No. 11222544, the Fok Ying Tung Education Foundation under Grant No. 131008, and the Program for New Century Excellent Talents in University (NCET-12-0121).
文摘Phase transitions are being used increasingly to probe the collective behaviors of social human systems. In this study, we propose a different way of investigating such transitions in a human system by establishing a two-sided minority game model. A new type of agents who can actively transfer resources are added to our artificial bipartite resource-allocation market. The degree of deviation from equilibria is characterized by the entropy-like quantity of market complexity. Under different threshold values, Qth, two phases are found by calculating the exponents of the associated power spectra. For large values of Qth, the general motion of strategies for the agents is relatively periodic whereas for low values of Qth, the motion becomes chaotic. The transition occurs abruptly at a critical value of Qty. Our simulation results were also tested based on human experiments. The results of this study suggest that a chaotic-periodic transition related to the quantity of market information should exist in most bipartite markets, thereby allowing better control of such a transi- tion and providing a better understanding of the endogenous emergence of business cycles from the perspective of quantum mechanics.
基金We acknowledge the financial support by the National Natural Science Foundation of China under Grant Nos. 11222544 and 11304284 (Y. Wang), the Fok Ying Tung Edu- cation Foundation under Grant No. 131008, the Program for New Century Excellent Talents in University (Grant No. NCET-12- 0121), and the CNKBRSF under Grant No. 2011CB922004. The computational resources utilized in this research were provided by Shanghai Supercomputer Center.
文摘In the past two decades, statistical physics was brought into the field of finance, applying new methods and concepts to financial time series and developing a new interdiscipline "econophysics". In this review, we introduce several commonly used methods for stock time series in econophysics including distribution functions, correlation functions, detrended fluctuation analysis method, de- trended moving average method, and multifractal analysis. Then based on these methods, we review some statistical properties of Chinese stock markets including scaling behavior, long-term correla- tions, cross-correlations, leverage effects, antileverage effects, and multifractality. Last, based on an agent-based model, we develop a new option pricing model -- financial market model that shows a good agreement with the prices using real Shanghai Index data. This review is helpful for people to understand and research statistical physics of financial markets.
文摘We propose a general method to realize a total scattering of an incident acoustic wave at interfaces between different media while allowing the flow of air, fluids and/or particles. This originates from the enlargement of the equivalent acoustic scattering cross section of an embedded object coated with acoustic metamaterials, which causes the coated object to behave as a scatterer bigger than its physical size. We theoretically design a model circular cylindrical object coated with such meta- materials whose properties are determined according to two different, but identical, methods. The desired function is confirmed for both far-field and near-field cases with full wave simulations based on the finite element method. This work reveals a promising way to achieve noise shielding and naval camouflage.
文摘Agent-based modeling and controlled human experiments serve as two fundamental research methods in the field of econophysics. Agent-based modeling has been in development for over 20 years, but how to design virtual agents with high levels of human-like "intelligence" remains a challenge. On the other hand, experimental econophysics is an emerging field; however, there is a lack of experience and paradigms related to the field. Here, we review some of the most recent research results obtained through the use of these two methods concerning financial problems such as chaos, leverage, and business cycles. We also review the principles behind assessments of agents' intelligence levels, and some relevant designs for human experiments. The main theme of this review is to show that by combining theory, agent-based modeling, and controlled human experiments, one can garner more reliable and credible results on account of a better verification of theory; accordingly, this way, a wider range of economic and financial problems and phenomena can be studied.
文摘Confinement can induce unusual behaviors of water. Inspired by the fabrication of carbon nanotubes with noncircular cross sections, we performed molecular dynamics simulations to investigate the mobilities of water confined in carbon nanochannels with circular, square, and equilateral triangular cross sections over a variety of dimensions. We find that water exhibits disparate mobilities across different types of channels below 0.796 nm(2). Notably, compared with the other two channels, water in equilateral triangular channels displays the greatest mobilities. Moreover, at 0.425 nm(2), different ordered structures are found in the three channels, and water inside the square channel exhibits an extremely low mobility. It is also found that above 0.796 nm(2), the mobilities along the tube axis of water converge to that of the bulk. These phenomena are understood by analyzing the structure, dynamics, and hydrogen bonding of water. Our work explores the mobilities of water across noncircular carbon nanochannels, which may expand the prospect of noncircular nanochannels in scientific studies and practical applications, such as desalination and drug delivery.
文摘The transmission spectra of a TiO2-silicone oil suspension in an increasing external electric field are studied. As the electric field increases, the structure of the suspension changes from a disordered one to an ordered one. Interestingly, the transmission spectra blueshift in this structure-ordering process. Furthermore, the relative transmission spectra exhibit Fano-like asymmetric line shapes. The deviation ratio of each asymmetric line shape increases monotonously as the disorder of the suspension decreases. We suggest that this blueshift phenomenon can be used to characterize the disorder strength of three- dimensional systems.
基金C.Z. Fan and E. J. Liang acknowledge the financial support by tile National Natural Science Founda- tion of China (Grant No. 11104252)the Ministry of Education of China (No. 20114101110003)+6 种基金by tile fund for Science and Technology innovation team of Zhengzhou (2011-03) the Basic and Frontier Technology Research Program of Henan Province (No. 122300410162) and the cooperation fired with Fudan University (No. KL2011-01) J. P. Ituang acknowledges the support by the Chinese National Key Basic Research Special Fund under Grant No. 2011CB922004 Fok Ying Tung Education Foundation under Grant No. 131008 the National Natural Science Foundation of China under Grant Nos. 11075035 and 11222544 and Shanghai Rising-Star Program (No. 12QA1400200).