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In chameleon field theories a scalar field can couple to matter with gravitational strength and still evade local gravity constraints due to a combination of self-interactions and the couplings to matter. Originally, these theories were…

Cosmology and Nongalactic Astrophysics · Physics 2011-05-02 David F. Mota , Hans A. Winther

We present an algorithm to solve the problem of locating the source, or maxima, of a scalar field using a robot swarm. We demonstrate how the robot swarm determines its direction of movement to approach the source using only field intensity…

Robotics · Computer Science 2024-08-20 Antonio Acuaviva , Hector Garcia de Marina , Juan Jimenez

In N-body simulations the force calculated between particles representing a given mass distribution is usually softened, to diminish the effect of graininess. In this paper we study the effect of such a smoothing, with the aim of finding an…

Astrophysics · Physics 2009-10-31 E. Athanassoula , E. Fady , J. -C. Lambert , A. Bosma

We report the first results from the GammeV search for chameleon particles, which may be created via photon-photon interactions within a strong magnetic field. Chameleons are hypothesized scalar fields that could explain the dark energy…

High Energy Physics - Experiment · Physics 2009-02-18 A. S. Chou , W. Wester , A. Baumbaugh , H. R. Gustafson , Y. Irizarry-Valle , P. O. Mazur , J. H. Steffen , R. Tomlin , A. Upadhye , A. Weltman , X. Yang , J. Yoo

The acceleration of the expansion of the Universe has led to the construction of Dark Energy models where a light scalar field may have a range reaching up to cosmological scales. Screening mechanisms allow these models to evade the tight…

High Energy Physics - Theory · Physics 2012-11-26 Philippe Brax

Scalar fields, strongly coupled to matter, can be present in nature and still be invisible to local experiments if they are subject to a screening mechanism. The symmetron is one such mechanism which relies on restoration of a spontaneously…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Anne-Christine Davis , Baojiu Li , David F. Mota , Hans A. Winther

By studying the chameleon gravity on galaxy scales, we investigate the effects of the chameleon dark matter. To perform this task, we consider the dynamics of the chameleon scalar field in the region of galactic halos in static spherically…

General Relativity and Quantum Cosmology · Physics 2025-07-22 Raziyeh Zaregonbadi , Nasim Saba , Mehrdad Farhoudi

New fifth forces have not yet been detected in the laboratory or in the solar system, hence it is typically difficult to introduce new light scalar fields that would mediate such forces. In recent years it has been shown that a number of…

High Energy Physics - Theory · Physics 2015-06-11 Philippe Brax , Clare Burrage , Anne-Christine Davis

Object detection in aerial imagery presents a significant challenge due to large scale variations among objects. This paper proposes an evolutionary reinforcement learning agent, integrated within a coarse-to-fine object detection…

Computer Vision and Pattern Recognition · Computer Science 2023-12-27 Jialu Zhang , Xiaoying Yang , Wentao He , Jianfeng Ren , Qian Zhang , Titian Zhao , Ruibin Bai , Xiangjian He , Jiang Liu

We investigate a chameleon scalar field dynamically interacting with a Kiselev-type metric, where the static anisotropic fluid part of the metric is replaced by a density-dependent scalar field non-minimally coupled to curvature. This…

General Relativity and Quantum Cosmology · Physics 2025-08-08 M. V. Pradosh Keshav , V. Jithesh , Kenath Arun

In this paper, a novel mechanism-driven reinforcement learning framework is proposed for airfoil shape optimization. To validate the framework, a reward function is designed and analyzed, from which the equivalence between the maximizing…

Numerical Analysis · Mathematics 2024-05-28 Jingfeng Wang , Guanghui Hu

Thin-film solar cells are predominately designed similar to a stacked structure. Optimizing the layer thicknesses in this stack structure is crucial to extract the best efficiency of the solar cell. The commonplace method used in…

Neural and Evolutionary Computing · Computer Science 2020-04-08 Premkumar Vincent , Gwenaelle Cunha Sergio , Jaewon Jang , In Man Kang , Jaehoon Park , Hyeok Kim , Minho Lee , Jin-Hyuk Bae

We offer predictions of symmetron modified gravity in the neighborhood of realistic dark matter halos. The predictions for the fifth force are obtained by solving the nonlinear symmetron equation of motion in the spherical NFW…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Joseph Clampitt , Bhuvnesh Jain , Justin Khoury

We consider modified gravity models driven by a scalar field whose effects are screened in high density regions due to the presence of non-linearities in its interaction potential and/or its coupling to matter. Our approach covers…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Philippe Brax , Anne-Christine Davis , Baojiu Li , Hans A. Winther

In this study, we investigate the inverse source problem arising in bioluminescence tomography, the objective of which is to reconstruct both the support and the intensity of an internal light source from boundary measurements governed by…

Numerical Analysis · Mathematics 2025-11-25 Qianqian Wu , Rongfang Gong , Wei Gong , Ziyi Zhang , Shengfeng Zhu

We explore the potential of conducting an experiment in a low Earth orbit spacecraft and using the Earth as a spin and mass source to constrain beyond-the-standard-model (BSM) long-range spin- and velocity-dependent interactions, which are…

High Energy Physics - Phenomenology · Physics 2026-04-13 Zheng-Ting Lai , Jun-Xu Lu , Li-Sheng Geng , Kai Wei , Wei Ji

In molecular dynamics (MD) simulation, force field determines the capability of an individual model in capturing physical and chemistry properties. The method for generating proper parameters of the force field form is the key component for…

Atomic and Molecular Clusters · Physics 2016-07-19 Ying Li , Hui Li , Maria K. Y. Chan , Subramanian Sankaranarayanan , Benoît Rouxb

We revisit the fermion mass problem of the $SU(5)$ grand unified theory using machine learning techniques. The original $SU(5)$ model proposed by Georgi and Glashow is incompatible with the observed fermion mass spectrum. Two remedies are…

High Energy Physics - Phenomenology · Physics 2026-05-19 Fayez Abu-Ajamieh , Shinsuke Kawai , Nobuchika Okada

Theories which modify general relativity to explain the accelerated expansion of the Universe often use screening mechanisms to satisfy constraints on Solar System scales. We investigate the effects of the cosmic web and the local…

Cosmology and Nongalactic Astrophysics · Physics 2015-07-31 Bridget Falck , Kazuya Koyama , Gong-bo Zhao

In this paper, we study the distribution of dark matter halos and voids using high resolution simulations in f(R) gravity models with the chameleon mechanism to screen the fifth force in dense environment. For dark matter halos, we show…

Cosmology and Nongalactic Astrophysics · Physics 2012-07-04 Baojiu Li , Gong-Bo Zhao , Kazuya Koyama
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