arXiv subjects

Guocheng Wang

Publications and source records attributed to Guocheng Wang.

8 recordsLinked to original sources

arXiv2025

Evolution of social behaviors in noisy environments

Evolutionary game theory offers a general framework to study how behaviors evolve by social learning in a population. This body of theory can accommodate a range of social dilemmas, or games, as well as real-world complexities such as spatial structure or behaviors conditioned on reputations. Nonetheless, this approach typically assumes a deterministic payoff structure for social interactions. Here, we extend evolutionary game theory to account for random changes in the social environment, so that mutual cooperation may bring different rewards today than it brings tomorrow, for example. Even when such environmental noise is unbiased, we find it can have a qualitative impact on the behaviors that evolve in a population. Noisy payoffs can permit the stable co-existence of cooperators and defectors in the prisoner's dilemma, for example, as well as bistability in snowdrift games and stable limit cycles in rock-paper-scissors games -- dynamical phenomena that cannot occur in the absence of noise. We conclude by discussing the relevance of our framework to scenarios where the nature of social interactions is subject to external perturbations.

physics.soc-ph↗

arXiv2024

A Theory of Complex Adaptive Learning and a Non-Localized Wave Equation in Quantum Mechanics

Complex adaptive learning is intelligent. It is adaptive, learns in feedback loops, and generates hidden patterns as many individuals, elements or particles interact in complex adaptive systems (CAS). CAS highlights adaptation in life and lifeless complex systems cutting across all traditional natural and social sciences disciplines. However, discovering a universal law in CAS and understanding the underlying mechanism of distribution formation, such as a non-Gauss distribution in complex quantum entanglement, remains highly challenging. Quantifying the uncertainty of CAS by probability wave functions, the authors explore the inherent logical relationship between Schrödinger's wave equation in quantum mechanics and Shi's trading volume-price wave equation in finance. Subsequently, the authors propose a non-localized wave equation in quantum mechanics if cumulative observable in a time interval represents momentum or momentum force in Skinner-Shi (reinforcement-frequency-interaction) coordinates. It reveals that the invariance of interaction as a universal law exists in quantum mechanics and finance. The theory shows that quantum entanglement is an interactively coherent state instead of a consequence of the superposition of coherent states. As a resource, quantum entanglement is non-separable, steerable, and energy-consumed. The entanglement state has opposite states subject to interaction conservation between the momentum and reversal forces. Keywords: complex adaptive systems, complex adaptive learning, complex quantum systems, non-localized wave equation, interaction conservation, interactively coherent entanglement PACS: 89.75.-k (Complex Systems); 89.65.Gh (Economics, Econophysics, Financial Markets, Business and Management); 03.65.Ud (Entanglement and Quantum Nonlocality)

q-fin.GN↗

arXiv2023

Decreasing emissions and increasing sink capacity to support China in achieving carbon neutrality before 2060

In September 2020, President Xi Jinping announced that China strives to achieve carbon neutrality before 2060. This ambitious and bold commitment was well received by the global community. However, the technology and pathway are not so clear. Here, we conducted an extensive review covering more than 200 published papers and summarized the key technologies to achieve carbon neutrality. We projected sectoral CO2 emissions for 2020-2050 based on our previous studies and published scenarios. We applied a medium sink scenario for terrestrial sinks due to the potential resource competition and included an ocean sink, which has generally not been included in previous estimates. We analyzed and revisited China's historical terrestrial carbon sink capacity from 1980-2020 based on multiple models and a literature review. To achieve neutrality, it is necessary to increase sink capacity and decrease emissions from many sources. On the one hand, critical measures to reduce emissions include decreasing the use of fossil fuels; substantially increasing the proportion of the renewable energy and nuclear energy. On the other hand, the capacity of future carbon sinks is projected to decrease due to the natural evolution of terrestrial ecosystems, and anthropogenic management practices are needed to increase sink capacity, including increasing the forest sinks through national ecological restoration projects and large-scale land greening campaigns; increasing wood harvesting and storage; and developing CCUS. This paper provides basic source and sink data,and established and promising new technologies for decreasing emissions and increasing sinks for use by the scientific community and policy makers.

physics.ao-ph↗

arXiv2022

The arrow of evolution when the offspring variance is large

The concept of fitness is central to evolution, but it quantifies only the expected number of offspring an individual will produce. The actual number of offspring is also subject to noise, arising from environmental or demographic stochasticity. In nature, individuals who are more fecund tend to have greater variance in their offspring number -- sometimes far greater than the Poisson variance assumed in classical models of population genetics. Here, we develop a model for the evolution of two types reproducing in a population of non-constant size. The frequency-dependent fitness of each type is determined by pairwise interactions in a prisoner's dilemma game, but the offspring number is subject to an exogenously controlled variance that may depend upon the mean. Whereas defectors are preferred by natural selection in classical well-mixed populations, since they always have greater fitness than cooperators, we show that large offspring variance can reverse the direction of evolution and favor cooperation. Reproductive over-dispersion produces qualitatively new dynamics for other types of social interactions, as well, which cannot arise in populations with a fixed size or Poisson offspring variance.

q-bio.PE↗

arXiv2021

Evolution of cooperation with joint liability

"Personal responsibility", one of the basic principles of modern law, requires one to be responsible for what he did. However, personal responsibility is far from the only norm ruling human interactions, especially in social and economic activities. In many collective communities such as among enterprise colleagues and family members, one's personal interests are often bound to others' -- once one member breaks the rule, a group of people have to bear the punishment or sanction. Such a mechanism is termed "joint liability". Although many real-world cases have demonstrated that joint liability helps to maintain collective collaboration, a deep and systematic theoretical analysis on how and when joint liability promotes cooperation is lacking. Here we use evolutionary game theory to model an interacting system with joint liability, where one's losing credit could deteriorate the reputation of the whole group. We provide the analytical condition to predict when cooperation evolves in the presence of joint liability, which is verified by simulations. We also analytically prove that joint liability can greatly promote cooperation. Our work stresses that joint liability is of great significance in promoting the current economic propensity.

physics.soc-ph↗

arXiv2021

State-clustering method of payoff computation in repeated multiplayer games

Direct reciprocity is a well-known mechanism that could explain how cooperation emerges and prevails in an evolving population. Numerous prior researches have studied the emergence of cooperation in multiplayer games. However, most of them use numerical or experimental methods, not theoretical analysis. This lack of theoretical works on the evolution of cooperation is due to the high complexity of calculating payoffs. In this paper, we propose a new method, namely, the state-clustering method to calculate the long-term payoffs in repeated games. Using this method, in an $n$-player repeated game, the computing complexity is reduced from $O(2^n)$ to $O(n^2)$, which makes it possible to compute a large-scale repeated game's payoff. We explore the evolution of cooperation in both infinitely and finitely repeated public goods games as an example to show the effectiveness of our method. In both cases, we find that when the synergy factor is sufficiently large, the increasing number of participants in a game is detrimental to the evolution of cooperation. Our work provides a theoretical approach to study the evolution of cooperation in repeated multiplayer games.

q-bio.PE↗

arXiv2020

Similarity and delay between two non-narrow-band time signals

Correlation coefficient is usually used to measure the correlation degree between two time signals. However, its performance will drop or even fail if the signals are noised. Based on the time-frequency phase spectrum (TFPS) provided by normal time-frequency transform (NTFT), similarity coefficient is proposed to measure the similarity between two non-narrow-band time signals, even if the signals are noised. The basic idea of the similarity coefficient is to translate the interest part of signal f1(t)'s TFPS along the time axis to couple with signal f2(t)'s TFPS. Such coupling would generate a maximum if f1(t)and f2(t) are really similar to each other in time-frequency structure. The maximum, if normalized, is called similarity coefficient. The location of the maximum indicates the time delay between f1(t) and f2(t). Numerical results show that the similarity coefficient is better than the correlation coefficient in measuring the correlation degree between two noised signals. Precision and accuracy of the time delay estimation (TDE) based on the similarity analysis are much better than those based on cross-correlation (CC) method and generalized CC (GCC) method under low SNR.

eess.SP↗

arXiv2014

Tailoring mechanical properties and electrical conductivity of flexible niobium carbide nanocomposite thin films

Flexible NbC nanocomposite thin films with carbon content ranging from 0 to 99 at.% were deposited at room temperature on Si (100) and polystyrene substrates by non-reactive magnetron sputtering from pure Nb and C targets without applying bias voltage to the substrates. HRTEM images reveal that the films exhibit a nanocomposite structure consisting of NbC nanocrystals (2 to 15 nm in size) embedded in an amorphous carbon matrix. By simply adjusting the Nb flux in the plasma, we can monitor the nanocrystal size and the percent of free-carbon phase in the films, which in turn allows for the tailoring of both mechanical properties and electric conductivity of the films. It was found that the films composed of ~8-10% free-carbon exhibited a relative high hardness and elastic recovery, around 23 GPa and 85%, respectively, and an electrical conductivity of 2.2x106 S/m at 22C. This study indicates the potential of this non-reactive sputtering approach in depositing hard, elastic and electrically conductive nanocomposite films at low temperatures, which is especially useful for preparation of films on temperature sensitive polymers or plastic substrates for nano- and micro- electronics applications.

cond-mat.mtrl-sci↗