Results for "Fernando Castanos"

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Sliding Motions on SO(3), Sliding SubgroupsMay 14 2019We propose a sliding surface for systems on the Lie group $SO(3)\times \mathbb{R}^3$ . The sliding surface is shown to be a Lie subgroup. The reduced-order dynamics along the sliding subgroup have an almost globally asymptotically stable equilibrium. ... More
Self-oscillations in an Alpha Stirling Engine: a bifurcation analysisMay 26 2019We study a thermo-mechanical system comprised of an alpha Stirling engine and a flywheel from the perspective of dynamical systems theory. Thermodynamics establish a static relation between the flywheel's angle and the forces exerted by the two power ... More
Finding the Topic of a Set of ImagesJun 25 2016In this paper we introduce the problem of determining the topic that a set of images is describing, where every topic is represented as a set of words. Different from other problems like tag assignment or similar, a) we assume multiple images are used ... More
A level N reduction theory of indefinite binary quadratic formsMar 06 2006In this paper we study a geometric coding algorithm for indefinite binary quadratic forms Q for the congruence subgroup \Gamma^0(N), with respect to the usual fundamental domain FN, where N is assumed prime. The cycles Q_1, . . ., Q_n that this algorithm ... More
Coding the real locus of X_0+(N)Mar 05 2006Mar 07 2017Let X_0+(N) be the Atkin-Lehner quotient of the modular curve X_0(N) associated to the Fricke involution wN. Assume N > 3 prime and endow the real locus X+ 0 (N)(R) with the real topology. In this paper we revisit a special case of result due to Ogg on ... More
A Matching Game for Data Trading in Operator-Supervised User-Provided NetworksFeb 16 2016In this paper, we consider a recent cellular network connection paradigm, known as user-provided network (UPN), where users share their connectivity and act as an access point for other users. To incentivize user participation in this network, we allow ... More
Quasi-Frobenius functors. ApplicationsDec 21 2006Sep 03 2008We investigate functors between abelian categories having a left adjoint and a right adjoint that are \emph{similar} (these functors are called \emph{quasi-Frobenius functors}). We introduce the notion of a \emph{quasi-Frobenius bimodule} and give a characterization ... More
Mass and mixing angle patterns in the Standard Model and its Minimal Supersymmetric ExtensionApr 22 1992Using renormalization group techniques, we examine several interesting relations among masses and mixing angles of quarks and leptons in the Standard Model. We extend the analysis to the minimal supersymmetric extension to determine its effect on these ... More
Renormalization Group Study of the Standard Model and its Extensions: II. the Minimal Supersymmetric Standard ModelAug 25 1993In this paper we summarize the minimal supersymmetric standard model as well as the renormalization group equations of its parameters. We proceed to examine the feasability of the model when the breaking of supersymmetry is parametrized by the soft terms ... More
Enveloping actions and Takai duality for partial actionsJul 17 2000We show that any continuous partial action on a topological space has a unique enveloping action, i.e. it is the restriction of a global action. In the case of C^*-algebras we prove that any partial action has an enveloping action up to Morita equivalence. ... More
Propagation properties and limitations on the attainable entanglement in a driven harmonic chainJan 11 2011The limitations on the production and profitability of entanglement in a harmonic chain under strong driving are considered. We report on the limits of attainable entanglement for a given set of squeezings of the eigenmodes, showing that the higher the ... More
Quantum MagnetohydrodynamicsMar 02 2005The quantum hydrodynamic model for charged particle systems is extended to the cases of non zero magnetic fields. In this way, quantum corrections to magnetohydrodynamics are obtained starting from the quantum hydrodynamical model with magnetic fields. ... More
On the relevance of quantum models for plasmasOct 01 2012Recently there has been a claim on the complete irrelevance of quantum modeling for plasmas. We address this subject from basic principles. Physical situations where quantum effects play a decisive role are identified.
The damped Pinney equation and its applications to dissipative quantum mechanicsDec 25 2007Dec 18 2009The work considers the damped Pinney equation, defined as the model arising when a linear in velocity damping term is included in the Pinney equation. In the general case the resulting equation does not admit Lie point symmetries or is reducible to a ... More
Aspects of quantum cooling in electron and atom systemsMay 18 2009Some features of nonadiabatic electron heat pumps are studied and connected to general questions of quantum cooling. Inelastic reflection is shown to contribute to heating if the external driving signal is time-symmetric. The quantum of cooling power, ... More
P-V criticality in AdS black holes of massive gravityNov 16 2016Nov 30 2016In this paper we have studied the extended phase space thermodynamics in the canonical ensemble of black holes in massive gravity in AdS space. The black holes considered here belong to a theory of massive gravity where the graviton gain a mass due to ... More
Phase transitions of black holes in massive gravityMay 16 2016May 19 2016In this paper we have studied thermodynamics of a black hole in massive gravity in the canonical ensemble. The massive gravity theory in consideration here has a massive graviton due to Lorentz symmetry breaking. The black hole studied here has a scalar ... More
A note on the automorphism group of Schubert varietiesMay 12 2016In this work we extend results on the automorphism group of Schubert varieties. We consider the Schubert conditions which define a Schubert variety. It turns out that an automorphism of the Grassmannian fixes a Schubert variety contained in it if and ... More
Nariai black holes with quintessenceAug 21 2014In this paper we study the properties of Schwarzschild black hole surrounded by quintessence matter. The main objective of the paper is to show the existence of Nariai type black hole for special values of the parameters in the theory. The Nariai black ... More
Extremal Surfaces in Asymptotically AdS Charged Boson Stars BackgroundsJan 18 2013In this paper, inspired by the holographic dual of the entanglement entropy, we consider the behaviour of extremal, codimension two, spacelike surfaces in the background of three and four dimensional charged boson stars in asymptotically anti-de Sitter ... More
Schwarzschild black hole surrounded by quintessence: Null geodesicsFeb 07 2012Aug 15 2014We have studied the null geodesics of the Schwarzschild black hole surrounded by quintessence matter. Quintessence matter is a candidate for dark energy. Here, we have done a detailed analysis of the geodesics and exact solutions are presented in terms ... More
Phase transitions of black holes in massive gravityMay 16 2016Dec 14 2016In this paper we have studied thermodynamics of a black hole in massive gravity in the canonical ensemble. The massive gravity theory in consideration here has a massive graviton due to Lorentz symmetry breaking. The black hole studied here has a scalar ... More
Counting Spanning trees in double nested graphsMay 16 2016In this paper we give a linear time algorithm for computing the number of spanninig trees in double nested graphs.
On certain N--sheeted coverings and numerical semigroups which cannot be realized as Weierstrass semigroupsJul 26 1994Mar 06 1995A curve $X$ is said to be of type $(N,\gamma)$ if it is an $N$--sheeted covering of a curve of genus $\gamma$ with at least one totally ramified point. A numerical semigroup $H$ is said to be of type $(N,\gamma)$ if it has $\gamma$ positive multiples ... More
Remarks on numerical semigroupsDec 19 1995We extend results on Weierstrass semigroups at ramified points of double covering of curves to any numerical semigroup whose genus is large enough. As an application we strengthen the properties concerning Weierstrass weights in \cited{To}.
On the proper homotopy type of locally compact A^2_n-polyhedraMay 08 2006In this paper we address the classification problem for locally compact (n-1)-connected CW-complexes with dimension less or equal than n+2 up to proper homotopy type. We obtain complete classification theorems in terms of purely algebraic data in those ... More
Operator algebras: an informal overviewJan 02 2009In this article we give a short and informal overview of some aspects of the theory of C*- and von Neumann algebras. We also mention some classical results and applications of these families of operator algebras.
Learning Entrepreneurship with Serious Games - A Classroom ApproachSep 18 2017The use of educational games for pedagogical practice can provide new conceptions of teaching-learning in an interactive environment stimulating the acquisition of new knowledge. The so-called serious games are focused on the goal of transmitting educational ... More
Modeling of relativistic ion-acoustic waves in ultra-degenerate plasmasDec 14 2017We consider the relativistic ion-acoustic mode in a plasma composed by cold ions and an ultra-degenerate electron gas, described the relativistic Vlasov-Poisson system. A critical examination of popular fluid models for relativistic ion-acoustic waves ... More
Spinning dilaton black hole in 2+1 dimensions as a particle acceleratorMar 01 2017In this paper we have studied particle collision around a spinning dilaton black hole in 2 +1 dimensions. This black hole is a solution to the low energy string theory in 2+1 dimensions. Time-like geodesics are presented in detail and the center of mass ... More
Charged dilaton black hole in 2+1 dimensions as a particle acceleratorMar 29 2017In this paper we have studied particle collisions around a charged dilaton black hole in 2+1 dimensions. This black hole is a solution to the low energy string action in 2+1 dimensions. Time-like geodesics for charged particles are studied in detail. ... More
Is String Phenomenology an Oxymoron?Dec 05 2016Dec 13 2016A brief discussion is presented assessing the achievements and challenges of string phenomenology: the subfield dedicated to study the potential for string theory to make contact with particle physics and cosmology. Building from the well understood case ... More
Representation theory of some infinite-dimensional algebras arising in continuously controlled algebra and topologyOct 21 2003In this paper we determine the representation type of some algebras of infinite matrices continuously controlled at infinity by a compact metrizable space. We explicitly classify their finitely presented modules in the finite and tame cases. The algebra ... More
Dilations of interaction groups that extend actions of Ore semigroupsAug 05 2010We show that every interaction group extending an action of an Ore semigroup by injective unital endomorphisms of a C*-algebra, admits a dilation to an action of the corresponding enveloping group on another unital C*-algebra, of which the former is a ... More
Modular reduction of the Steinberg lattice of the general linear groupAug 21 2013The modular reduction of the Steinberg lattice of the general linear group is studied
TwistBytes -- Hierarchical Classification at GermEval 2019: walking the fine line (of recall and precision)Aug 18 2019We present here our approach to the GermEval 2019 Task 1 - Shared Task on hierarchical classification of German blurbs. We achieved first place in the hierarchical subtask B and second place on the root node, flat classification subtask A. In subtask ... More
The deterministic limit of the Moran model: a uniform central limit theoremAug 21 2015We consider a Moran model with two allelic types, mutation and selection. In this work, we study the behaviour of the proportion of fit individuals when the size of the population tends to infinity, without any rescaling of parameters or time. We first ... More
Modular representations of Heisenberg algebrasJun 18 2013Jun 20 2013Let $F$ be be an arbitrary field and let $h(n)$ be the Heisenberg algebra of dimension $2n+1$ over $F$. It was shown by Burde that if $F$ has characteristic 0 then the minimum dimension of a faithful $h(n)$-module is $n+2$. We show here that his result ... More
On the 2-modular reduction of the Steinberg representation of the symplectic groupDec 30 2002We show that in characteristic 2, the Steinberg representation of the symplectic group Sp(2n,q), q a power of an odd prime p, has two irreducible constituents lying just above the socle that are isomorphic to the two Weil modules of degree (q^n-1)/2.
Elastic forces that do no work and the dynamics of fast cracksJul 17 1995Jul 18 1995Elastic singularities such as crack tips, when in motion through a medium that is itself vibrating, are subject to forces orthogonal to the direction of motion and thus impossible to determine by energy considerations alone. This fact is used to propose ... More
Quantum Weibel InstabilityNov 06 2007The Weibel instability is analyzed for quantum plasmas described by the Wigner-Maxwell model. For a suitable class of electromagnetic potentials, the Wigner-Maxwell system is linearized yielding a general dispersion relation for transverse electromagnetic ... More
Josephson effect between Bose condensatesOct 26 1998I present an overview of the physics of the Josephson effect between Bose condensed systems, with emphasis on the recently achieved BEC's in trapped alkali gases. I focus mostly on those physical phenomena that are likely to be observed only (or more ... More
On the scaling property in fluctuation theory for stable Lévy processesJul 22 2010We find an expression for the joint Laplace transform of the law of $(T_{[x,+\infty[},X_{T_{[x,+\infty[}})$ for a L\'evy process $X$, where $T_{[x,+\infty[}$ is the first hitting time of $[x,+\infty[$ by $X$. When $X$ is an $\alpha$-stable L\'evy process, ... More
Quasi normal modes and the area spectrum of a near extremal de Sitter black hole with conformally coupled scalar fieldApr 14 2015In this paper we have studied a black hole in de Sitter space which has a conformally coupled scalar field in the background. This black hole is also known as the $MTZ$ black hole. We have obtained exact values for the quasi normal mode frequencies under ... More
On an Inequality of Dimension-like Invariants for Finite GroupsFeb 02 2015In this paper, we introduce several notions of "dimension" of a finite group, involving sizes of generating sets and certain configurations of maximal subgroups. We focus on the inequality $m(G) \leq \mathrm{MaxDim}(G)$, giving a family of examples where ... More
Enhanced $A$-infinity obstruction theoryOct 01 2015We define a new obstruction theory for the extension of truncated A-infinity algebra structures. Obstructions lie in the new terms of a spectral sequence which extends Bousfield-Kan's fringed spectral sequence of a certain tower of fibrations. The obstructions ... More
Wave dispersion derived from the square-root Klein-Gordon-Poisson systemJul 30 2013Recently there has been great interest around quantum relativistic models for plasmas. In particular striking advances have been obtained by means of the Klein-Gordon-Maxwell system, which provides a first order approach to the relativistic regimes of ... More
On the splitting ring of a polynomialApr 04 2015Oct 16 2015Let $f(Z)=Z^n-a_{1}Z^{n-1}+\cdots+(-1)^{n-1}a_{n-1}Z+(-1)^na_n$ be a monic polynomial with coefficients in a ring~$R$ with identity, not necessarily commutative. We study the ideal $I_f$ of $R[X_1,\dots,X_n]$ generated by $\sigma_i(X_1,\dots,X_n)-a_{i}$, ... More
Pseudo-Query ReformulationJul 14 2015Automatic query reformulation refers to rewriting a user's original query in order to improve the ranking of retrieval results compared to the original query. We present a general framework for automatic query reformulation based on discrete optimization. ... More
Born-Infeld-de Sitter gravity: Cold, ultracold and Nariai black holesDec 30 2013Aug 16 2014In this paper, we have presented interesting properties of the static charged Born-Infeld-de Sitter black hole. They can have time-like as well as space-like singularities depending on the parameters of the theory. The degenerate black holes lead to cold, ... More
Quasinormal modes of dilaton-de Sitter black holes: scalar perturbationsJan 24 2016Dilaton black hole solutions in low energy string theory (well known as GMGHS black holes) have analogue black holes with a cosmological constant derived by Gao and Zhang. Here, we study quasi normal modes of this dilaton-de Sitter black hole under neutral ... More
Hamilton-Dirac systems for charged particles in gauge fieldsOct 13 2014Apr 07 2015In this work, we use the Sternberg phase space (which may be considered as the classical phase space of particles in gauge fields) in order to explore the dynamics of such particles in the context of Hamilton-Dirac systems and their associated Hamilton-Pontryagin ... More
Superstring Phenomenology: An OverviewJul 22 1997The different aspects of superstring phenomenology before and after 1995 are briefly reviewed. (Contribution to the conference SUSY97)
Duality and Global SymmetriesJun 27 1997This is a general introduction to duality in field theories. The existence and breaking of global symmetries is used as a guideline to systematically prove duality between different field theories. Systems discussed include abelian and non-abelian T-duality ... More
The Deligne-Lusztig curve associated to the Suzuki groupJun 26 1997We give a characterization of the Deligne-Lusztig curve associated to the Suzuki group based on the genus and the number of rational points of the curve.
Some Graded Identities of The Cayley-Dickson AlgebraMay 22 2012We work to find a basis of graded identities for the octonion algebra. We do so for the $\mathbb{Z}_2^2$ and $\mathbb{Z}_2^3$ gradings, both of them derived of the Cayley-Dickson process, the later grading being possible only when the characteristic of ... More
On spectral approximation, Følner sequences and crossed productsAug 06 2010Oct 09 2012In this article we study Foelner sequences for operators and mention their relation to spectral approximation problems. We construct a canonical Foelner sequence for the crossed product of a discrete amenable group $\Gamma$ with a concrete C*-algebra ... More
Equivalence and congruence of matrices under the action of standard parabolic subgroupsAug 21 2013We find necessary and sufficient conditions for $P$-equivalence of arbitrary matrices and $P$-congruence of symmetric and alternating matrices, where $P$ is standard parabolic subgroup of $GL_n(F)$ and $F$ is an arbitrary field.
The first passage time of a stable process conditioned to not overshootNov 15 2012Jan 07 2015Consider a stable L\'evy process $X=(X_t,t\geq 0)$ and let $T_x$, for $x>0$, denote the first passage time of $X$ above the level $x$. In this work, we give an alternative proof of the absolute continuity of the law of $T_x$ and we obtain a new expression ... More
Massive gravity with Lorentz symmetry breaking: black holes as heat enginesAug 26 2018In extended phase space, a static black hole in massive gravity is studied as a holographic heat engine. In the massive gravity theory considered, the graviton gain a mass due to Lorentz symmetry breaking. Exact efficiency formula is obtained for a rectangle ... More
On the possibility of nonlinear de Broglie relations for very-high-energy photonsMay 20 2019While quantum field theory is at the heart of our understanding of a large variety of phenomena, there remains some discrepancies between theoretically predicted and observed quantities in the very-high-energy (VHE) domain. In this work, starting from ... More
Sufficient conditions for the convergence of the Magnus expansionNov 15 2007Two different sufficient conditions are given for the convergence of the Magnus expansion arising in the study of the linear differential equation $Y' = A(t) Y$. The first one provides a bound on the convergence domain based on the norm of the operator ... More
On the unit of a monoidal model categoryNov 05 2014Nov 13 2014In this paper we show how to modify cofibrations in a monoidal model category so that the tensor unit becomes cofibrant while keeping the same weak equivalences. We obtain aplications to enriched categories and coloured operads in stable homotopy theory. ... More
Reversed Dickson Polynomials of the Third KindFeb 15 2016Aug 08 2016Let $p$ be a prime and $q=p^e$. We discuss the properties of the reversed Dickson polynomial $D_{n,2}(1,x)$ of the third kind. We also give several necessary conditions for the reversed Dickson polynomial of the third kind $D_{n,2}(1,x)$ to be a permutation ... More
Homotopy theory of non-symmetric operadsJan 09 2011We endow categories of non-symmetric operads with natural model structures. We work with no restriction on our operads and only assume the usual hypotheses for model categories with a symmetric monoidal structure. We also study categories of algebras ... More
Hyperbolic classification of natural numbers and Goldbach ConjectureJul 17 2005Jun 22 2007By means of a dynamical process we provide a characterization of the Goldbach Conjecture in an infinite set of even numbers that depends on time.
Associativity of the Commutator Operation in GroupsMay 30 2008The study of associativity of the commutator operation in groups goes back to some work of Levi in 1942. In the 1960's Richard J. Thompson created a group F whose elements are representatives of the generalized associative law for an arbitrary binary ... More
The first obstructions to enhancing a triangulated categoryMar 06 2018In this paper we relate triangulated category structures to the cohomology of small categories and define initial obstructions to the existence of an algebraic or topological enhancement. We show that these obstructions do not vanish in an example of ... More
Enhanced finite triangulated categoriesOct 23 2018Feb 20 2019We give a necessary and sufficient condition for the existence of an enhancement of a finite triangulated category. Moreover, we show that enhancements are unique when they exist, up to Morita equivalence.
Singular 2 webs and Polar CurvesApr 21 2013A 2-web in the plane is given by two everywhere transverse 1-foliations. In this paper we introduce the study of singular 2-webs, given by any two foliations, which may be tangent in some points. We show that such two foliations are tangent along a curve, ... More
Entanglement and Localization of a Two-Mode Bose-Einstein CondensateOct 17 2009A simple second quantization model is used to describe a two-mode Bose-Einstein condensate (BEC), which can be written in terms of the generators of a SU(2) algebra with three parameters. We study the behaviour of the entanglement entropy and localization ... More
New Parametrizations for the Photon Structure FunctionJan 07 2006In the last year four new parametrizations of the Hadronic Photon Structure Function at Next to Leading Order have appeared. In this talk, I briefly review the main features of three of them: the FFNS_CJK, CJK and AFG.
Geometric properties of RM vector fields along curves in Riemannian manifoldsSep 27 2016Rotation minimizing vector fields and frames were introduced by Bishop as an alternative to the Frenet frame. They are used in CAGD because they can be defined even the curvature vanishes. Nevertheless, many other geometric properties have not been studied. ... More
Black holes in massive gravity: quasinormal modes of Dirac field perturbationsJun 09 2015We have studied quasinormal modes of spinor $\frac{1}{2}$, massless Dirac field perturbations of a black hole in massive gravity. The parameters of the theory, such as the mass of the black hole, the scalar charge of the black hole, mode number and the ... More
Cold, ultracold and Nariai black holes with quintessenceJan 03 2014In this paper, we study the properties of the charged black hole surrounded by the quintessence. The solution space for the horizons for various values of the mass $M$, charge $Q$, and the quintessence parameter $\alpha$ are studied in detail. Special ... More
A Note on Permutation Binomials and Trinomials over Finite FieldsSep 22 2016Let $p$ be a prime and $e$ be a positive integer. We completely explain the permutation binomials and trinomials arising from the reversed Dickson polynomials of the $(k+1)$-th kind $D_{n,k}(1,x)$ over $\mathbb{F}_{p^e}$ when $n=p^l+2$, where $l\in \mathbb{N}$. ... More
Casimir effect around disclinationsMay 05 1995This communication concerns the structure of the electromagnetic quantum vacuum in a disclinated insulator. It is shown that a nonzero vacuum energy density appears when the rotational symmetry of a continuous insulating elastic medium is broken by a ... More
Enhancement of the magnetic moment of the electron due to a topological defectMay 23 1995In the framework of the theory of defects/three-dimensional gravitation, it is obtained a positive correction to the magnetic moment of the electron bound to a disclination in a dielectric solid.
Design for a Darwinian Brain: Part 1. Philosophy and NeuroscienceMar 28 2013Physical symbol systems are needed for open-ended cognition. A good way to understand physical symbol systems is by comparison of thought to chemistry. Both have systematicity, productivity and compositionality. The state of the art in cognitive architectures ... More
Non-Euclidean visibility problemsJul 27 2006We consider the analog of visibility problems in hyperbolic plane (represented by Poincar\'{e} half-plane model H), replacing the standard lattice $Z\times Z$ by the orbit $z=i$ under the full modular group $z$. We prove a visibility criterion and study ... More
Bounding the order of automorphisms of certain curvesNov 28 1994Aug 19 1995We study upper bounds on the order of automorphisms of non-singular curves $X$ satisfying at least one of the following hypothesis: 1) $X$ is an $m$-sheeted covering of exactly one non-singular curve of genus $\gamma$, where $m$ is prime; 2) the center ... More
Conformal covariance of massless free netsJun 16 2000In the present paper we review in a fibre bundle context the covariant and massless canonical representations of the Poincare' group as well as certain unitary representations of the conformal group (in 4 dimensions). We give a simplified proof of the ... More
Rotation Minimizing vector fields and frames in Riemannian manifoldsApr 27 2013We prove that a normal vector field along a curve in R3 is rotation minimizing (RM) if and only if it is parallel respect to the normal connection. This allows us to generalize all the results of RM vectors and frames to curves immersed in Riemannian ... More
Modular Theory by exampleJan 08 2009The present article contains a short introduction to Modular Theory for von Neumann algebras with a cyclic and separating vector. It includes the formulation of the central result in this area, the Tomita-Takesaki theorem, and several of its consequences. ... More
A Note on Permutation Binomials and Trinomials over Finite FieldsSep 22 2016Feb 05 2017Let $p$ be an odd prime and $e$ be a positive integer. We completely explain the permutation binomials and trinomials arising from the reversed Dickson polynomials of the $(k+1)$-th kind $D_{n,k}(1,x)$ over $\mathbb{F}_{p^e}$ when $n=p^l+2$, where $l\in ... More
More on Equienergetic Threshold GraphsJul 02 2018The energy of a graph is defined as the sum the absolute values of the eigenvalues of its adjacency matrix. A threshold graph G on n vertices is coded by a binary sequence of length n. In this paper we answer a question posed by Jacobs et al. [Eigenvalues ... More
Conjugacy classes of p-cycles of type D in alternating groupsNov 27 2012Mar 04 2014We classify the conjugacy classes of p-cycles of type D in alternating groups. This finishes the open cases in arXiv:0812.4628. We also determine all the subracks of those conjugacy classes which are not of type D.
Cylinders for non-symmetric DG-operads via homological perturbation theoryMay 12 2015We construct small cylinders for cellular non-symmetric DG-operads over an arbitrary commutative ring by using the basic perturbation lemma from homological algebra. We show that our construction, applied to the A-infinity operad, yields the operad parametrizing ... More
Enhanced $A$-infinity obstruction theoryOct 01 2015Mar 12 2018We extend the Bousfield-Kan spectral sequence for the computation of the homotopy groups of the space of minimal A-infinity algebra structures on a graded projective module. We use the new part to define obstructions to the extension of truncated minimal ... More
Geometric properties of rotation minimizing vector fields along curves in Riemannian manifoldsSep 27 2016Mar 29 2017Rotation minimizing vector fields and frames were introduced by Bishop as an alternative to the Frenet frame. They are used in CAGD because they can be defined even the curvature vanishes. Nevertheless, many other geometric properties have not been studied. ... More
A triangulated category without modelsMar 11 2007We exhibit a triangulated category which is neither the stable category of a Frobenius category nor a full triangulated subcategory of the homotopy category of a stable model category.
Explicit solutions of Jensen's auxiliary equations via extremal Lipschitz extensionsJul 22 2019In this note we prove that McShane and Whitney's Lipschitz extensions are viscosity solutions of Jensen's auxiliary equations, known to have a key role in Jensen's celebrated proof of uniqueness of infinity harmonic functions, and therefore of Absolutely ... More
P-V criticality in AdS black holes of massive gravityNov 16 2016In this paper we have studied the extended phase space thermodynamics in the canonical ensemble of black holes in massive gravity in AdS space. The black holes considered here belong to a theory of massive gravity where the graviton gain a mass due to ... More
An introduction to quantum plasmasJun 05 2012Shielding effects in non-degenerate and degenerate plasmas are compared. A detailed derivation of the Wigner-Poisson system is provided for electrostatic quantum plasmas where relativistic, spin and collisional effects are not essential. Later a detailed ... More
Corrections to "Homotopy theory of nonsymmetric operads, I, II"Jul 23 2015We correct a mistake in the construction of push-outs along free morphisms of algebras over a nonsymmetric operad in arXiv:1101.1634 [math.AT], and we fix the affected results in arXiv:1101.1634 [math.AT] and arXiv:1304.6641 [math.AT].
Slowly Oscillating Solution of the Cubic Heat EquationJul 03 2015In this paper, we are considering the Cauchy problem of the nonlinear heat equation $u\_t -\Delta u= u^{3 },\ u(0,x)=u\_0$. After extending Y. Meyer's result establishing the existence of global solutions, under a smallness condition of the initial data ... More
Structure of the group preserving a bilinear formJun 18 2013We study the group of all linear automorphisms preserving an arbitrary bilinear form
Groups having a faithful irreducible representationApr 06 2015Jan 12 2016We address the problem of finding necessary and sufficient conditions for an arbitrary group, not necessarily finite, to admit a faithful irreducible representation over an arbitrary field.
Mechanical Design of Superconducting Accelerator MagnetsJan 13 2015This paper is about the mechanical design of superconducting accelerator magnets. First, we give a brief review of the basic concepts and terms. In the following sections, we describe the particularities of the mechanical design of different types of ... More
Active Brownian RodsDec 23 2015Here, I review the large-scale properties of collections of active Brownian elongated objects, in particular rods, moving in a dissipative medium/substrate. I address the problem by presenting three different models of decreasing complexity, which I refer ... More