4,463 research outputs found
Opinion dynamics on directed small-world networks
In this paper, we investigate the self-affirmation effect on formation of
public opinion in a directed small-world social network. The system presents a
non-equilibrium phase transition from a consensus state to a disordered state
with coexistence of opinions. The dynamical behaviors are very sensitive to the
density of long-range interactions and the strength of self-affirmation. When
the long-range interactions are sparse and individual generally does not insist
on his/her opinion, the system will display a continuous phase transition, in
the opposite case with high self-affirmation strength and dense long-range
interactions, the system does not display a phase transition. Between those two
extreme cases, the system undergoes a discontinuous phase transition.Comment: 6 pages, 5 figure
Heavy surface state in a possible topological Kondo insulator: Magneto-thermoelectric transport on the (011)-plane of SmB
Motivated by the high sensitivity to Fermi surface topology and scattering
mechanisms in magneto-thermoelectric transport, we have measured the
thermopower and Nernst effect on the (011)-plane of the proposed topological
Kondo insulator SmB. These experiments, together with electrical
resistivity and Hall effect measurements, demonstrate that the (011)-plane also
harbors a metallic surface with the effective mass in the order of 10-10
. The surface and bulk conductances are well distinguished in these
measurements and are categorized into metallic and non-degenerate
semiconducting regimes, respectively. Electronic correlations play an important
role in enhancing scattering and also contribute to the heavy surface state.Comment: 4 figures, 1 tabl
Structural evolution and characterization of organic-rich shale from macroscopic to microscopic resolution: The significance of tectonic activity
Shale gas exploration and development have taken significant strides in the relatively straightforward intra-basin stability zone and intra-basin weak deformation zone of marine shale in the Sichuan Basin, South China. In addition, the extra-basin strong tectonic modification zones have been actively explored. However, the results have been limited, which reveals the complexity of shale gas formation and preservation conditions in the context of multi-scale geological processes. These tectonic geological conditions have a significant impact on the shale gas content, while it has been difficult to figure out how tectonic deformation modifies reservoir structure and what specific mechanism causes shale gas content anomalies. Based on subjecting geologic samples to combined high-temperature and high-pressure experiments, this study summarizes the tectonic constraint mechanism of shale petrophysical structure evolution and its impact on shale gas storage, reveals the intrinsic connection and mechanism of shale pore-fracture and organic matter, inorganic mineral particle structure evolution and tectonic stress, and identifies the remodeling mechanism of the shale reservoir physical property change. The findings contribute to the theory of shale deformation and gas accumulation, as well as offer a scientific foundation for the exploration of marine shale gas in the complex tectonic zones outside the Sichuan Basin.Document Type: PerspectiveCited as: Gao, J., Li, X., Cheng, G., Luo, H., Zhu, H. Structural evolution and characterization of organic-rich shale from macroscopic to microscopic resolution: The significance of tectonic activity. Advances in Geo-Energy Research, 2023, 10(2): 84-90. https://doi.org/10.46690/ager.2023.11.0
Soft Theorem to Three Loops in QCD and Super Yang-Mills Theory
The soft theorem states that scattering amplitude in gauge theory with a soft
gauge-boson emission can be factorized into a hard scattering amplitude and a
soft factor. In this paper, we present calculations of the soft factor for
processes involving two hard colored partons, up to three loops in QCD. To
accomplish this, we developed a systematic method for recursively calculating
relevant Feynman integrals using the Feynman-Parameter representation. Our
results constitute an important ingredient for the subtraction of infrared
singularities at NLO in perturbative QCD. Using the principle of leading
transcendentality between QCD and super Yang-Mills theory, we
determine the soft factor in the latter case to three loops with full-color
dependence. As a by-product, we also obtain the finite constant in
the Bern-Dixon-Smirnov ansatz analytically, which was previously known
numerically only.Comment: 31 pages, ancillary files provided, matches published versio
Microlensing effect of charged spherically symmetric wormhole
We systematically investigate the microlensing effect of charged spherically
symmetric wormhole, where the light source is remote from the throat.
Remarkably, there will be at most three images by considering the charge part.
We study all situations including three images, two images, and one image,
respectively. The numerical result shows that the range of total magnification
is from to depending on various metrics. In the case of three
images, there will be two maximal values of magnification (a peak, and a gentle
peak) when the contribution via mass is much less than that of charge. However,
we cannot distinguish the case that forms three images or only one image as the
total magnification is of order . Finally, our theoretical investigation
could shed new light on exploring the wormhole with the microlensing effect.Comment: 10 pages, 9 figure
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