Results 11 to 20 of about 1,675 (45)

Response of nucleons to external probes in hedgehog models: II. General formalism [PDF]

Phys.Rev. D47 (1993) 313-324, 1992
Linear response theory for SU(2) hedgehog soliton models is developed.
arxiv   +1 more source

Hedgehogs in Wilson loops and phase transition in SU(2) Yang-Mills theory [PDF]

Nucl.Phys.B748:524-539,2006, 2005
We suggest that the gauge-invariant hedgehoglike structures in the Wilson loops are physically interesting degrees of freedom in the Yang--Mills theory. The trajectories of these ``hedgehog loops'' are closed curves corresponding to center-valued (untraced) Wilson loops and are characterized by the center charge and winding number.
arxiv   +1 more source

Gotta Learn Fast: A New Benchmark for Generalization in RL [PDF]

arXiv, 2018
In this report, we present a new reinforcement learning (RL) benchmark based on the Sonic the Hedgehog (TM) video game franchise. This benchmark is intended to measure the performance of transfer learning and few-shot learning algorithms in the RL domain. We also present and evaluate some baseline algorithms on the new benchmark.
arxiv  

Supervise Thyself: Examining Self-Supervised Representations in Interactive Environments [PDF]

arXiv, 2019
Self-supervised methods, wherein an agent learns representations solely by observing the results of its actions, become crucial in environments which do not provide a dense reward signal or have labels. In most cases, such methods are used for pretraining or auxiliary tasks for "downstream" tasks, such as control, exploration, or imitation learning ...
arxiv  

Complete Conjugacy Invariants of Nonlinearizable Holomorphic Dynamics [PDF]

arXiv, 2009
Perez-Marco proved the existence of non-trivial totally invariant connected compacts called hedgehogs near the fixed point of a nonlinearizable germ of holomorphic diffeomorphism. We show that if two nonlinearisable holomorphic germs with a common indifferent fixed point have a common hedgehog then they must commute.
arxiv  

Hedgehogs of Hausdorff dimension one [PDF]

arXiv, 2009
We present a construction of hedgehogs for holomorphic maps with an indifferent fixed point. We construct, for a family of commuting non-linearisable maps, a common hedgehog of Hausdorff dimension 1, the minimum possible.
arxiv  

Smooth Combs Inside Hedgehogs [PDF]

arXiv, 2009
We use techniques of tube-log Riemann surfaces due to R.Perez-Marco to construct a hedgehog containing smooth $C^{\infty}$ combs. The hedgehog is a common hedgehog for a family of commuting non-linearisable holomorphic maps with a common indifferent fixed point. The comb is made up of smooth curves, and is transversally bi-H\"older regular.
arxiv  

The Radial-Hedgehog Solution in Landau--de Gennes' theory [PDF]

arXiv, 2010
We study the radial-hedgehog solution in a three-dimensional spherical droplet, with homeotropic boundary conditions, within the Landau-de Gennes theory for nematic liquid crystals. The radial-hedgehog solution is a candidate for a globally stable configuration in this model framework and is also a prototype configuration for studying isolated point ...
arxiv  

A tale of three hedgehogs [PDF]

arXiv, 2017
In this work we study three topologies defined over the same set: the hedgehog. As the name suggests, the hedgehog can be described as a set of spines identified at a single point. Among others, we give a proof of the Kowalsky hedgehog theorem, which asserts that every metrizable space is embeddable into a countable cartesian power of the metric ...
arxiv  

On a functional equation related to a pair of hedgehogs with congruent projections [PDF]

J. Math. Anal. Appl. 445 (2017) 1492-1504, 2016
Hedgehogs are geometrical objects that describe the Minkowski differences of arbitrary convex bodies in the Euclidean space $\mathbb{E}^n$. We prove that two hedgehogs in $\mathbb{E}^n, n \geq 3$, coincide up to a translation and a reflection in the origin, provided that their projections onto any two-dimensional plane are directly congruent and have ...
arxiv