Starting from generic bilinear Hamiltonians, constructed by covariant vector, bivector or tensor ... more Starting from generic bilinear Hamiltonians, constructed by covariant vector, bivector or tensor fields, it is possible to derive a general symplectic structure which leads to holonomic and anholonomic formulations of Hamilton equations of motion directly related to a hydrodynamic picture. This feature is gauge free and it seems a deep link common to all interactions, electromagnetism and gravity included. This scheme could lead toward a full canonical quantization.
The nonlinear dynamics of whistler waves in magnetized plasmas is studied. Since the plasmas and ... more The nonlinear dynamics of whistler waves in magnetized plasmas is studied. Since the plasmas and beam-plasma systems considered here are assumed to be weakly collisional, the point of reference for the analysis performed in the present paper is the system of hydrodynamic and field equations. The renormalization group method is applied to obtain dynamical equations for the slowly varying amplitudes of whistler waves. Further, it has been shown that the amplitudes of eigenmodes satisfy an infinite system of coupled nonlinear Schrödinger equations. In this sense, the whistler eigenmodes form a sort of a gas of interacting quasiparticles, while the slowly varying amplitudes can be considered as dynamical variables heralding the relevant information about the system. An important feature of the approach is that whistler waves do not perturb the initial uniform density of plasma electrons. The plasma response to the induced whistler waves consists in velocity redistribution which follows exactly the behavior of the whistlers. In addition, selection rules governing the nonlinear mode coupling have been derived, which represent another interesting peculiarity of the description presented here.
... ORIGINAL PAPER Angelo Ciaramella · Enza De Lauro Salvatore De Martino · Mariarosaria Falanga ... more ... ORIGINAL PAPER Angelo Ciaramella · Enza De Lauro Salvatore De Martino · Mariarosaria Falanga Roberto Tagliaferri ... 3.3 Chaotic DSs The studied chaotic systems are the Lorenz oscillator and Rossler system. Page 7. ICA based identification of DSGS and RWTS 593 Fig. ...
Journal of Physics A: Mathematical and General, 1989
ABSTRACT The microscopic model of Ullersma (1966) for a harmonic oscillator in contact with a the... more ABSTRACT The microscopic model of Ullersma (1966) for a harmonic oscillator in contact with a thermal reservoir is quantised in the framework of Nelson's stochastic mechanics. Eliminating the degrees of freedom of the thermal reservoir the stochastic process of the quantum Brownian oscillator is obtained as the sum of the thermal contribution and the quantum (zero-temperature) contribution. The properties of the quantum fluctuations are studied in detail and the equation of motion is derived, obtaining the first example of a non-Markovian Nelson process.
... LETTERS 11 February 1982PROBABILISTIC IDEAS FOR TWO-DIMENSIONAL INTERACTING FERMI FIELDS ON A... more ... LETTERS 11 February 1982PROBABILISTIC IDEAS FOR TWO-DIMENSIONAL INTERACTING FERMI FIELDS ON A LATTICEDiego DE FALCO 1,2, Salvatore DE MARTINO 2 and Silvio DE SIENA 2Istituto di ... 21 (1980) 1111.[2] GF De Angelis, D. de Falco and F. Guerra, Phys. ...
We present a study of the time decay of magnetic states in type-II superconductors. The mean esca... more We present a study of the time decay of magnetic states in type-II superconductors. The mean escape time of flux quanta from the pinning centers is calculated by considering the well-known washboard potential and a pinning potential appropriate to the case of pinning center dimensions l much larger than the coherence length ξ. We find that, in both cases, the attempt frequency in the Arrhenius formula depends on the current density J. Finally, by plotting the E(J) curves, we show that the dissipation due to flux creep mechanisms goes to zero much faster in the second case, where l ⪢ ξ is assumed.
Starting from generic bilinear Hamiltonians, constructed by covariant vector, bivector or tensor ... more Starting from generic bilinear Hamiltonians, constructed by covariant vector, bivector or tensor fields, it is possible to derive a general symplectic structure which leads to holonomic and anholonomic formulations of Hamilton equations of motion directly related to a hydrodynamic picture. This feature is gauge free and it seems a deep link common to all interactions, electromagnetism and gravity included. This scheme could lead toward a full canonical quantization.
The nonlinear dynamics of whistler waves in magnetized plasmas is studied. Since the plasmas and ... more The nonlinear dynamics of whistler waves in magnetized plasmas is studied. Since the plasmas and beam-plasma systems considered here are assumed to be weakly collisional, the point of reference for the analysis performed in the present paper is the system of hydrodynamic and field equations. The renormalization group method is applied to obtain dynamical equations for the slowly varying amplitudes of whistler waves. Further, it has been shown that the amplitudes of eigenmodes satisfy an infinite system of coupled nonlinear Schrödinger equations. In this sense, the whistler eigenmodes form a sort of a gas of interacting quasiparticles, while the slowly varying amplitudes can be considered as dynamical variables heralding the relevant information about the system. An important feature of the approach is that whistler waves do not perturb the initial uniform density of plasma electrons. The plasma response to the induced whistler waves consists in velocity redistribution which follows exactly the behavior of the whistlers. In addition, selection rules governing the nonlinear mode coupling have been derived, which represent another interesting peculiarity of the description presented here.
... ORIGINAL PAPER Angelo Ciaramella · Enza De Lauro Salvatore De Martino · Mariarosaria Falanga ... more ... ORIGINAL PAPER Angelo Ciaramella · Enza De Lauro Salvatore De Martino · Mariarosaria Falanga Roberto Tagliaferri ... 3.3 Chaotic DSs The studied chaotic systems are the Lorenz oscillator and Rossler system. Page 7. ICA based identification of DSGS and RWTS 593 Fig. ...
Journal of Physics A: Mathematical and General, 1989
ABSTRACT The microscopic model of Ullersma (1966) for a harmonic oscillator in contact with a the... more ABSTRACT The microscopic model of Ullersma (1966) for a harmonic oscillator in contact with a thermal reservoir is quantised in the framework of Nelson's stochastic mechanics. Eliminating the degrees of freedom of the thermal reservoir the stochastic process of the quantum Brownian oscillator is obtained as the sum of the thermal contribution and the quantum (zero-temperature) contribution. The properties of the quantum fluctuations are studied in detail and the equation of motion is derived, obtaining the first example of a non-Markovian Nelson process.
... LETTERS 11 February 1982PROBABILISTIC IDEAS FOR TWO-DIMENSIONAL INTERACTING FERMI FIELDS ON A... more ... LETTERS 11 February 1982PROBABILISTIC IDEAS FOR TWO-DIMENSIONAL INTERACTING FERMI FIELDS ON A LATTICEDiego DE FALCO 1,2, Salvatore DE MARTINO 2 and Silvio DE SIENA 2Istituto di ... 21 (1980) 1111.[2] GF De Angelis, D. de Falco and F. Guerra, Phys. ...
We present a study of the time decay of magnetic states in type-II superconductors. The mean esca... more We present a study of the time decay of magnetic states in type-II superconductors. The mean escape time of flux quanta from the pinning centers is calculated by considering the well-known washboard potential and a pinning potential appropriate to the case of pinning center dimensions l much larger than the coherence length ξ. We find that, in both cases, the attempt frequency in the Arrhenius formula depends on the current density J. Finally, by plotting the E(J) curves, we show that the dissipation due to flux creep mechanisms goes to zero much faster in the second case, where l ⪢ ξ is assumed.
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