Enrico Mazziotti - Academia.edu (original) (raw)
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Papers by Enrico Mazziotti
arXiv (Cornell University), Mar 11, 2012
The qualitative analysis of the initial value problem P related to a non linear third order parab... more The qualitative analysis of the initial value problem P related to a non linear third order parabolic equation typical of diffusive models is discussed. Some basic properties of the the fundamental solution of a related linear operator are determined and are applied to an equivalent integro differential formulation of the problem. By the fixed point theorem, existence and uniqueness results are obtained.
Annali Dell'universita' Di Ferrara, 1979
Riassunto Si studia la propagazione ondosa che si determina in un sistema viscoelastico lineare ... more Riassunto Si studia la propagazione ondosa che si determina in un sistema viscoelastico lineare sotto l'azione di assegnate forze di massa e per effetto di prefissate condizioni al contorno. Mediante l'analisi asintotica di una particolare serie di Neumann che interviene nella soluzione, si dimostrapoi l'esistenza di una regione di «strato limite» pert→∞, in corrispondenza di tempi di rilassamento molto «piccoli».
l 101 Convegno Nazionale AEIT, 2007
PAMM, 2008
In a real Hilbert space we investigate the existence, uniqueness and asymptotic properties of the... more In a real Hilbert space we investigate the existence, uniqueness and asymptotic properties of the strong and weak solutions to an infinite nonlinear differential system with second-order differences, subject to an extreme condition and initial data.
arXiv: Mathematical Physics, 2012
A third order parabolic operator L_\epsilon typical of a non linear wave operator cal L_0 perturb... more A third order parabolic operator L_\epsilon typical of a non linear wave operator cal L_0 perturbed by viscous terms, is analyzed. Some particular solutions related to L_0 are explicitly determined and the initial value problem for L_\epsilon is considered. The parabolic-hyperbolic behaviour is analyzed and rigorous approximations of the solution are achieved.
Relatività generale e fisica della gravitazione, 1986
Meccanica, 2015
We give an exhaustive, non-perturbative classification of exact travelling-wave solutions of a pe... more We give an exhaustive, non-perturbative classification of exact travelling-wave solutions of a perturbed sine-Gordon equation (on the real line or on the circle) which is used to describe the Josephson effect in the theory of superconductors and other remarkable physical phenomena. The perturbation of the equation consists of a constant forcing term and a linear dissipative term. On the real line candidate orbitally stable solutions with bounded energy density are either the constant one, or of kink (i.e. soliton) type, or of array-of-kinks type, or of "half-array-of-kinks" type. While the first three have unperturbed analogs, the last type is essentially new. We also propose a convergent method of successive approximations of the (anti)kink solution based on a careful application of the fixed point theorem.
Ricerche di Matematica, 2012
This work is focused on the geometrical and physical characteristics of the class of reference fr... more This work is focused on the geometrical and physical characteristics of the class of reference frames associated to harmonic coordinates. Precisely, we express in relative form the harmonicity conditions and consider the so called "spatially harmonicity" of a reference frame in spherical symmetry. The initial data problem is then analyzed in polar coordinates and the obtained results are applied to special cases of exact solutions.
Ricerche di Matematica, 2012
This work is focused on the geometrical and physical characteristics of the class of reference fr... more This work is focused on the geometrical and physical characteristics of the class of reference frames associated to harmonic coordinates. Precisely, we express in relative form the harmonicity conditions and consider the so called "spatially harmonicity" of a reference frame in spherical symmetry. The initial data problem is then analyzed in polar coordinates and the obtained results are applied to special cases of exact solutions.
Journal of Interdisciplinary Mathematics, 2009
This paper derrelops the studv of the geometrical characteristics of the class of frames of refer... more This paper derrelops the studv of the geometrical characteristics of the class of frames of reference associated rvith the tr.r'o u'ell known sets of coorclinates: Levi-Civita's curvature coclrdinates and ganssian polar coordinates. In particular, thr:ough the separate invariant forrnulation of the rrritial clata problem ancl oi the restricted errolntion problem, the analysis is applierl to a sphericallr, syrnmetric perfect flr-rid, r,r'hose stream lines coincide r,r'ith those of the above rnentiorrecl class of frames.
Journal of Interdisciplinary Mathematics, 2011
arXiv (Cornell University), Mar 11, 2012
The qualitative analysis of the initial value problem P related to a non linear third order parab... more The qualitative analysis of the initial value problem P related to a non linear third order parabolic equation typical of diffusive models is discussed. Some basic properties of the the fundamental solution of a related linear operator are determined and are applied to an equivalent integro differential formulation of the problem. By the fixed point theorem, existence and uniqueness results are obtained.
Annali Dell'universita' Di Ferrara, 1979
Riassunto Si studia la propagazione ondosa che si determina in un sistema viscoelastico lineare ... more Riassunto Si studia la propagazione ondosa che si determina in un sistema viscoelastico lineare sotto l'azione di assegnate forze di massa e per effetto di prefissate condizioni al contorno. Mediante l'analisi asintotica di una particolare serie di Neumann che interviene nella soluzione, si dimostrapoi l'esistenza di una regione di «strato limite» pert→∞, in corrispondenza di tempi di rilassamento molto «piccoli».
l 101 Convegno Nazionale AEIT, 2007
PAMM, 2008
In a real Hilbert space we investigate the existence, uniqueness and asymptotic properties of the... more In a real Hilbert space we investigate the existence, uniqueness and asymptotic properties of the strong and weak solutions to an infinite nonlinear differential system with second-order differences, subject to an extreme condition and initial data.
arXiv: Mathematical Physics, 2012
A third order parabolic operator L_\epsilon typical of a non linear wave operator cal L_0 perturb... more A third order parabolic operator L_\epsilon typical of a non linear wave operator cal L_0 perturbed by viscous terms, is analyzed. Some particular solutions related to L_0 are explicitly determined and the initial value problem for L_\epsilon is considered. The parabolic-hyperbolic behaviour is analyzed and rigorous approximations of the solution are achieved.
Relatività generale e fisica della gravitazione, 1986
Meccanica, 2015
We give an exhaustive, non-perturbative classification of exact travelling-wave solutions of a pe... more We give an exhaustive, non-perturbative classification of exact travelling-wave solutions of a perturbed sine-Gordon equation (on the real line or on the circle) which is used to describe the Josephson effect in the theory of superconductors and other remarkable physical phenomena. The perturbation of the equation consists of a constant forcing term and a linear dissipative term. On the real line candidate orbitally stable solutions with bounded energy density are either the constant one, or of kink (i.e. soliton) type, or of array-of-kinks type, or of "half-array-of-kinks" type. While the first three have unperturbed analogs, the last type is essentially new. We also propose a convergent method of successive approximations of the (anti)kink solution based on a careful application of the fixed point theorem.
Ricerche di Matematica, 2012
This work is focused on the geometrical and physical characteristics of the class of reference fr... more This work is focused on the geometrical and physical characteristics of the class of reference frames associated to harmonic coordinates. Precisely, we express in relative form the harmonicity conditions and consider the so called "spatially harmonicity" of a reference frame in spherical symmetry. The initial data problem is then analyzed in polar coordinates and the obtained results are applied to special cases of exact solutions.
Ricerche di Matematica, 2012
This work is focused on the geometrical and physical characteristics of the class of reference fr... more This work is focused on the geometrical and physical characteristics of the class of reference frames associated to harmonic coordinates. Precisely, we express in relative form the harmonicity conditions and consider the so called "spatially harmonicity" of a reference frame in spherical symmetry. The initial data problem is then analyzed in polar coordinates and the obtained results are applied to special cases of exact solutions.
Journal of Interdisciplinary Mathematics, 2009
This paper derrelops the studv of the geometrical characteristics of the class of frames of refer... more This paper derrelops the studv of the geometrical characteristics of the class of frames of reference associated rvith the tr.r'o u'ell known sets of coorclinates: Levi-Civita's curvature coclrdinates and ganssian polar coordinates. In particular, thr:ough the separate invariant forrnulation of the rrritial clata problem ancl oi the restricted errolntion problem, the analysis is applierl to a sphericallr, syrnmetric perfect flr-rid, r,r'hose stream lines coincide r,r'ith those of the above rnentiorrecl class of frames.
Journal of Interdisciplinary Mathematics, 2011