Displaying similar documents to “Continuity of the fundamental operations on distributions having a specified wave front set (with a counterexample by Semyon Alesker)”

One-parameter semigroups in the convolution algebra of rapidly decreasing distributions

(2012)

Colloquium Mathematicae

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The paper is devoted to infinitely differentiable one-parameter convolution semigroups in the convolution algebra C ' ( ; M m × m ) of matrix valued rapidly decreasing distributions on ℝⁿ. It is proved that G C ' ( ; M m × m ) is the generating distribution of an i.d.c.s. if and only if the operator t m × m - G on 1 + n satisfies the Petrovskiĭ condition for forward evolution. Some consequences are discussed.

Global stability of travelling fronts for a damped wave equation with bistable nonlinearity

Thierry Gallay, Romain Joly (2009)

Annales scientifiques de l'École Normale Supérieure

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We consider the damped wave equation α u t t + u t = u x x - V ' ( u ) on the whole real line, where V is a bistable potential. This equation has travelling front solutions of the form u ( x , t ) = h ( x - s t ) which describe a moving interface between two different steady states of the system, one of which being the global minimum of V . We show that, if the initial data are sufficiently close to the profile of a front for large | x | , the solution of the damped wave equation converges uniformly on to a travelling front as t + . The proof of this...

Free decay of solutions to wave equations on a curved background

Serge Alinhac (2005)

Bulletin de la Société Mathématique de France

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We investigate for which metric g (close to the standard metric g 0 ) the solutions of the corresponding d’Alembertian behave like free solutions of the standard wave equation. We give rather weak (, non integrable) decay conditions on g - g 0 ; in particular, g - g 0 decays like t - 1 2 - ε along wave cones.

Wave front set for positive operators and for positive elements in non-commutative convolution algebras

Joachim Toft (2007)

Studia Mathematica

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Let WF⁎ be the wave front set with respect to C , quasi analyticity or analyticity, and let K be the kernel of a positive operator from C to ’. We prove that if ξ ≠ 0 and (x,x,ξ,-ξ) ∉ WF⁎(K), then (x,y,ξ,-η) ∉ WF⁎(K) and (y,x,η,-ξ) ∉ WF⁎(K) for any y,η. We apply this property to positive elements with respect to the weighted convolution u B φ ( x ) = u ( x - y ) φ ( y ) B ( x , y ) d y , where B C is appropriate, and prove that if ( u B φ , φ ) 0 for every φ C and (0,ξ) ∉ WF⁎(u), then (x,ξ) ∉ WF⁎(u) for any x.

Nonlinear Hyperbolic Smoothing at a Focal Point

Jean-Luc Joly, Guy Métivier, Jeffrey Rauch (1998-1999)

Séminaire Équations aux dérivées partielles

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The nonlinear dissipative wave equation u t t - Δ u + | u t | h - 1 u t = 0 in dimension d > 1 has strong solutions with the following structure. In 0 t < 1 the solutions have a focusing wave of singularity on the incoming light cone | x | = 1 - t . In { t 1 } that is after the focusing time, they are smoother than they were in { 0 t < 1 } . The examples are radial and piecewise smooth in { 0 t < 1 }

Stability in exponential time of Minkowski space-time with a space-like translation symmetry

Cécile Huneau (2014-2015)

Séminaire Laurent Schwartz — EDP et applications

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In this note, we discuss the nonlinear stability in exponential time of Minkowski space-time with a translation space-like Killing field, proved in [13]. In the presence of such a symmetry, the 3 + 1 vacuum Einstein equations reduce to the 2 + 1 Einstein equations with a scalar field. We work in generalized wave coordinates. In this gauge Einstein equations can be written as a system of quasilinear quadratic wave equations. The main difficulty in [13] is due to the decay in 1 / t of free solutions...

Modeling of the resonance of an acoustic wave in a torus

Jérôme Adou, Adama Coulibaly, Narcisse Dakouri (2013)

Annales mathématiques Blaise Pascal

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A pneumatic tyre in rotating motion with a constant angular velocity Ω is assimilated to a torus whose generating circle has a radius R . The contact of the tyre with the ground is schematized as an ellipse with semi-major axis a . When ( Ω R / C 0 ) 1 and ( a / R ) 1 (where C 0 is the velocity of the sound), we show that at the rapid time scale R / C 0 , the air motion within a torus periodically excited on its surface generates an acoustic wave h . A study of this acoustic wave is conducted and shows that the mode associated...

Selfsimilar profiles in large time asymptotics of solutions to damped wave equations

Grzegorz Karch (2000)

Studia Mathematica

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Large time behavior of solutions to the generalized damped wave equation u t t + A u t + ν B u + F ( x , t , u , u t , u ) = 0 for ( x , t ) n × [ 0 , ) is studied. First, we consider the linear nonhomogeneous equation, i.e. with F = F(x,t) independent of u. We impose conditions on the operators A and B, on F, as well as on the initial data which lead to the selfsimilar large time asymptotics of solutions. Next, this abstract result is applied to the equation where A u t = u t , B u = - Δ u , and the nonlinear term is either | u t | q - 1 u t or | u | α - 1 u . In this case, the asymptotic profile of solutions...

On the Cauchy problem for convolution equations

(2013)

Colloquium Mathematicae

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We consider one-parameter (C₀)-semigroups of operators in the space ' ( ; m ) with infinitesimal generator of the form ( G * ) | ' ( ; m ) where G is an M m × m -valued rapidly decreasing distribution on ℝⁿ. It is proved that the Petrovskiĭ condition for forward evolution ensures not only the existence and uniqueness of the above semigroup but also its nice behaviour after restriction to whichever of the function spaces ( ; m ) , L p ( ; m ) , p ∈ [1,∞], ( a ) ( ; m ) , a ∈ ]0,∞[, or the spaces L q ' ( ; m ) , q ∈ ]1,∞], of bounded distributions.

Kernel theorems in spaces of generalized functions

Antoine Delcroix (2010)

Banach Center Publications

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In analogy to the classical isomorphism between ((ℝⁿ), ' ( m ) ) and ' ( m + n ) (resp. ( ( ) , ' ( m ) ) and ' ( m + n ) ), we show that a large class of moderate linear mappings acting between the space C ( ) of compactly supported generalized functions and (ℝⁿ) of generalized functions (resp. the space ( ) of Colombeau rapidly decreasing generalized functions and the space τ ( ) of temperate ones) admits generalized integral representations, with kernels belonging to specific regular subspaces of ( m + n ) (resp. τ ( m + n ) ). The main novelty is to use...

Some decay properties for the damped wave equation on the torus

Nalini Anantharaman, Matthieu Léautaud (2012)

Journées Équations aux dérivées partielles

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This article is a proceedings version of the ongoing work [1], and has been the object of a talk of the second author during the Journées “Équations aux Dérivées Partielles” (Biarritz, 2012). We address the decay rates of the energy of the damped wave equation when the damping coefficient b does not satisfy the Geometric Control Condition (GCC). First, we give a link with the controllability of the associated Schrödinger...

On isomorphic classification of tensor products E ( a ) ̂ E ' ( b )

Goncharov A., Zahariuta V., Terzioğlu Tosun

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Abstract New linear topological invariants are introduced and utilized to give an isomorphic classification of tensor products of the type E ( a ) ̂ E ' ( b ) , where E ( a ) is a power series space of infinite type. These invariants are modifications of those suggested earlier by Zahariuta. In particular, some new results are obtained for spaces of infinitely differentiable functions with values in a locally convex space X. These spaces coincide, up to isomorphism, with spaces L(s’,X) of all continuous linear...

Equicontinuity and Convergent Sequences in the Spaces C ' and M

Jan Kisyński (2011)

Bulletin of the Polish Academy of Sciences. Mathematics

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Characterizations of equicontinuity and convergent sequences are given for the space C ' ( ) of rapidly decreasing distributions and the space M ( ) of slowly increasing infinitely differentiable functions.

Breathers for nonlinear wave equations

Michael W. Smiley (1988)

Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti Lincei. Matematica e Applicazioni

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The semilinear differential equation (1), (2), (3), in × Ω with Ω N , (a nonlinear wave equation) is studied. In particular for Ω = 3 , the existence is shown of a weak solution u ( t , x ) , periodic with period T , non-constant with respect to t , and radially symmetric in the spatial variables, that is of the form u ( t , x ) = ν ( t , | x | ) . The proof is based on a distributional interpretation for a linear equation corresponding to the given problem, on the Paley-Wiener criterion for the Laplace Transform, and on the alternative...

Breathers for nonlinear wave equations

Michael W. Smiley (1988)

Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti

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The semilinear differential equation (1), (2), (3), in × Ω with Ω N , (a nonlinear wave equation) is studied. In particular for Ω = 3 , the existence is shown of a weak solution u ( t , x ) , periodic with period T , non-constant with respect to t , and radially symmetric in the spatial variables, that is of the form u ( t , x ) = ν ( t , | x | ) . The proof is based on a distributional interpretation for a linear equation corresponding to the given problem, on the Paley-Wiener criterion for the Laplace Transform, and on the alternative...

A new way to iterate Brzeziński crossed products

Leonard Dăuş, Florin Panaite (2016)

Colloquium Mathematicae

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If A R , σ V and A P , ν W are two Brzeziński crossed products and Q: W⊗ V → V⊗ W is a linear map satisfying certain properties, we construct a Brzeziński crossed product A S , θ ( V W ) . This construction contains as a particular case the iterated twisted tensor product of algebras.

Characterization of surjective convolution operators on Sato's hyperfunctions

Michael Langenbruch (2010)

Banach Center Publications

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Let μ ( d ) ' be an analytic functional and let T μ be the corresponding convolution operator on Sato’s space ( d ) of hyperfunctions. We show that T μ is surjective iff T μ admits an elementary solution in ( d ) iff the Fourier transform μ̂ satisfies Kawai’s slowly decreasing condition (S). We also show that there are 0 μ ( d ) ' such that T μ is not surjective on ( d ) .