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Related papers: Level Set Method for the Evolution of Defect and B…

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Level Set Estimation (LSE) is an important problem with applications in various fields such as material design, biotechnology, machine operational testing, etc. Existing techniques suffer from the scalability issue, that is, these methods…

Machine Learning · Statistics 2020-12-21 Huong Ha , Sunil Gupta , Santu Rana , Svetha Venkatesh

Cosmic strings may have formed in the early universe due to the Kibble mechanism. While string networks are usually modeled as being of Nambu-Goto type, this description is understood to be a convenient approximation, which neglects the…

Cosmology and Nongalactic Astrophysics · Physics 2021-09-01 A. R. R. Almeida , C. J. A. P. Martins

We developed a Nonlinear Level-set Learning (NLL) method for dimensionality reduction in high-dimensional function approximation with small data. This work is motivated by a variety of design tasks in real-world engineering applications,…

Functional Analysis · Mathematics 2019-06-20 Guannan Zhang , Jiaxin Zhang , Jacob Hinkle

We report on a large scale numerical study of networks of semilocal cosmic strings in flat space in the parameter regime in which they are perturbatively stable. We find a population of segments with an exponential length distribution and…

Astrophysics · Physics 2008-11-26 A. Achucarro , P. Salmi , J. Urrestilla

In this second part of the paper, dedicated to theories with extra dimensions, a new physical notion about the "tensor length scale" is introduced, based on the gravitational theories with covariant and contravariant metric tensor…

High Energy Physics - Theory · Physics 2008-10-09 Bogdan G. Dimitrov

We consider radial complex scaling/perfectly matched layer methods for scalar resonance problems in homogeneous exterior domains. We introduce a new abstract framework to analyze the convergence of domain truncations and discretizations.…

Numerical Analysis · Mathematics 2020-07-21 Martin Halla

We study global defects coupled to higher-dimensional gravity with a negative cosmological constant. This paper is mainly devoted to studying global black brane solutions which are extended global defects surrounded by horizons. We find…

High Energy Physics - Theory · Physics 2009-11-07 Sei-Hoon Moon

A model of a cloud formed by massive strings is used as a source of LRS Bianchi type II with time decaying vacuum energy density $\Lambda$. To construct string cosmological models we have used the energy-momentum tensor for such string as…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-29 Hassan Amirhashchi

Field-level inference is emerging as a promising technique for optimally extracting information from cosmological datasets. Indeed, previous analyses have shown field-based inference produces tighter parameter constraints than power…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-04 Supranta S. Boruah , Eduardo Rozo

We consider gradient-based optimisation of wide, shallow neural networks, where the output of each hidden node is scaled by a positive parameter. The scaling parameters are non-identical, differing from the classical Neural Tangent Kernel…

Machine Learning · Statistics 2025-02-19 Francois Caron , Fadhel Ayed , Paul Jung , Hoil Lee , Juho Lee , Hongseok Yang

Scale transformations have played an extremely successful role in studies of cosmological large-scale structure by relating the non-linear spectrum of cosmological density fluctuations to the linear primordial power at longer wavelengths.…

Astrophysics · Physics 2009-11-13 Jun Pan , Peter Coles , Istvan Szapudi

Chiral cosmic strings are produced naturally at the end of inflation in supersymmetric models where the symmetry is broken via a D-term. Consequently in such theories, where both inflation and cosmic strings contribute to the density and…

Astrophysics · Physics 2009-10-31 A. C. Davis , T. W. B. Kibble , M. Pickles , D. A. Steer

We show that quantum systems of extended objects naturally give rise to a large class of exotic phases - namely topological phases. These phases occur when the extended objects, called ``string-nets'', become highly fluctuating and…

Strongly Correlated Electrons · Physics 2009-11-10 Michael A. Levin , Xiao-Gang Wen

New classes of distance-constrained structures are introduced, namely string-node nets and meshes, a mesh being a string-node net for which the nodes are dense in the strings. Various construction schemes are given including the minimal…

Metric Geometry · Mathematics 2016-09-12 S. C. Power , B. Schulze

We develop a velocity-dependent one-scale model for the evolution of domain wall networks in flat expanding or collapsing homogeneous and isotropic universes with an arbitrary number of spatial dimensions, finding the corresponding scaling…

High Energy Physics - Theory · Physics 2011-03-18 P. P. Avelino , L. Sousa

After presenting string-like solutions with a warp factor to Einstein's equations, we study localization of various spin fields on a string-like defect in a general space-time dimension from the viewpoint of field theory. It is shown that…

High Energy Physics - Theory · Physics 2011-05-05 Ichiro Oda

The vast combination of material properties seen in nature are achieved by the complexity of the material microstructure. Advanced characterization and physics based simulation techniques have led to generation of extremely large…

Machine Learning · Computer Science 2023-01-12 Veera Sundararaghavan , Megna N. Shah , Jeff P. Simmons

Zero-point fluctuations in the background of a cosmic string provide an opportunity to study the effects of topology in quantum field theory. We use a scattering theory approach to compute quantum corrections to the energy density of a…

High Energy Physics - Theory · Physics 2025-05-26 M. Koike , X. Laquidain , N. Graham

An analytic approach to phenomenological models inspired by cubic string field theory is introduced and applied to some examples. We study a class of actions for a minimally coupled, homogeneous scalar field whose energy density contains…

High Energy Physics - Theory · Physics 2008-11-26 Gianluca Calcagni , Michele Montobbio , Giuseppe Nardelli

The string tensions can be dynamical in the modified measure formalism and appear as an additional dynamical degrees of freedom . These tensions may not be universal, instead, each string generates its own tension. We then consider a new…

General Physics · Physics 2026-05-13 Eduardo Guendelman