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Papers by Giovanni Scelza
Modern Physics Letters B, 2010
A new analogy between superfluid systems and cosmology is here presented, which relies strongly o... more A new analogy between superfluid systems and cosmology is here presented, which relies strongly on the following ingredient: the back-reaction of the vacuum to the quanta of sound waves. We show how the presence of thermal phonons, the excitations above the quantum vacuum for T > 0, enable us to deduce an hydrodynamical equation formally similar to the one obtained for a perfect fluid in a Universe obeying the Friedmann–Robertson–Walker metric.
Physica Scripta, 2019
It is explicitly shown that a one-family parameter model reproducing the nonlinear Newton-Schrod... more It is explicitly shown that a one-family parameter model reproducing the nonlinear Newton-Schrodinger
equation as the parameter goes to in nity is free from any causality violation problem for any nite value
of it. This circumstance arises from the intrinsic mechanism of spontaneous state reduction of the model,
absent in the Newton-Schrodinger limit. A speci c ideal EPR experiment involving a superposition of two
distinct CM's position states of a massive lump is analyzed, showing recovered compatibility with QM.
Besides, the new framework suggests a soft version of the Many Worlds Interpretation, in which the typical
indiscriminate proliferation of Everett branches, together with the bizarre inter-branches communications
made possible by nonlinearity, are strongly suppressed in the macroscopic world by the same mechanism of
state reduction.
Astrophys Space Sci, 2015
In this paper we present the discussion on the salient points of the computational analysis that ... more In this paper we present the discussion on the salient points of the computational analysis that are at the basis of the paper Rotation Curves of Galaxies by Fourth Order Gravity [1]. In fact in this paper any galactic component (bulge, disk and Dark matter component) required an onerous numerical computation since the Gauss theorem is not applicable in the Fourth Order Gravity. The computational and data analysis have been made with the software Mathematica .
Journal of Physics Communications
The result of a numerical simulation of two interacting particles in the framework of Nonunitary ... more The result of a numerical simulation of two interacting particles in the framework of Nonunitary Newtonian Gravity is presented here. Particles are held close together by a 3-d harmonic trap and interact with each other via an 'electrical' delta-like potential and via the ordinary Newtonian term, together with a fluctuational nonunitary counterpart of the latter. Fundamental nonunitarity can be seen as arising from the interaction of the physical degrees of freedom with (gravitational) hidden copies of them. Starting from an energy eigenstate within the ordinary setting, it is shown that, while energy expectation remains constant, a slow net variation of the von Neumann entropy for the system as a whole takes place, with a small modulation induced on the relative entanglement entropy of the two particles. Besides, the simulation shows explicitly how fundamental gravity-induced entropy can be clearly distinguished from the subjective notion of coarse-grained entropy, i.e. from the entropy of one particle with respect to the 'environment' of the other.
We investigate the radial behavior of galactic rotation curves by a Fourth Order Gravity adding a... more We investigate the radial behavior of galactic rotation curves by a Fourth Order Gravity adding also the Dark Matter component. The Fourth Order Gravity is a theory of Gravity described by Lagrangian generalizing the one of Hilbert Einstein containing a generic function of the Ricci scalar, the Ricci and Riemann tensor. A systematic analysis of rotation curves, in the Newtonian Limit of theory, induced by all galactic sub-structures of ordinary matter is shown. This analysis is presented for Fourth Order Gravity with and without Dark Matter. The outcomes are compared with respect to the classical outcomes of General Relativity. The gravitational potential of point-like mass is the usual potential corrected by two Yukawa terms. The rotation curve is higher or also lower than curve of General Relativity if in the Lagrangian the Ricci scalar square is dominant or not with respect to the contribution of the Ricci tensor square. The theoretical spatial behaviors of rotation curve are compared with the experimental data for the Milky Way and the galaxy NGC 3198. Although the Fourth Order Gravity gives more rotational contributions, in the limit of large distances the Keplerian behavior is ever present, and it is missing only if we add the Dark Matter component. However by modifying the theory of Gravity, consequently, also the spatial description of Dark Matter could undergo a modification and the free parameters of model can assume different values. After an analytical discussion of theoretical behaviors and the comparing with experimental evidence we can claim that any Fourth Order Gravity is not successful to explain the galactic rotation curves. In the last part of paper we analyze the gravitational potential induced by Lagrangian containing only powers of Ricci scalar. In this case we find an inconsistency in the boundary conditions in the passage from matter to the vacuum.
Phis. Rev. A, 2011
Aim of this work is to calculate explicitly the result of the experiment of superposition of a mi... more Aim of this work is to calculate explicitly the result of the
experiment of superposition of a mirror in the Michelson photon
cavities interferometric device proposed by Marshall, Simon,
Penrose and Bownmeester, as expected within a recently proposed
model of non-unitary self-gravity inducing localization. As for
other proposals of modifications of Quantum Mechanics in a
non-unitary sense, aimed to account for both unitary evolution and
irreversible collapse, like in the famous Ghirardi-Rimini-Weber
and Pearle's models, it turns out that, for the experimental
parameters proposed, no effect is detectable at all. It is pointed
out that the enhancing properties of matter granularity does not
substantially change this conclusion. Parameters have also been
exploratively varied in a certain range beyond the proposed
values. It is shown that within `sensible' parameters, that are
not yet attainable within current technology, the model exhibits a
peculiar signature with respect to other collapse models as far as
parameters space is explored. Besides, the calculation offers a
way to see non-unitary gravity at work in a quasi-realistic
setting.
The new formal analogy between superfluid systems and cosmology, which emerges by taking into acc... more The new formal analogy between superfluid systems and cosmology,
which emerges by taking into account the back-reaction of the
vacuum to the quanta of sound waves \cite{noi}, enables us to put
forward some common features between these two different areas of
physics. We find the condition that allows us to justify a General
Relativity (GR) derivation of the hydrodynamical equation for the
superfluid in a four-dimensional space whose metric is the Unruh
one \cite{Unruh}. Furthermore we show how, in the particular case
taken into account, our hydrodynamical equation can be deduced
within a four-dimensional space from the wave equation of a
massless scalar field.
A new analogy between superfluid systems and cosmology is here presented, which relies strongly o... more A new analogy between superfluid systems and cosmology is here
presented, which relies strongly on the following ingredient: the
back-reaction of the vacuum to the quanta of sound waves. We show
how the presence of thermal phonons, the excitations above the
quantum vacuum for T>0T> 0T>0, enable us to deduce an hydrodynamical
equation formally similar to the one obtained for a perfect fluid
in a Universe obeying the Friedmann-Robertson-Walker metric.
Drafts by Giovanni Scelza
International Journal of Quantum Information, 2019
The quest for a microscopic foundation of Thermodynamics is addressed within the Nonunitary New-t... more The quest for a microscopic foundation of Thermodynamics is addressed within the Nonunitary New-tonian Gravity model through the study of a specific closed system, namely a three-dimensional harmonic nanocrystal. A numerical calculation of the nanocrystal von Neumann entropy as a function of time is performed, showing a sharp monotonic increase, followed by a stabilization at late times. This behavior is consistent with the emergence of a micro-canonical ensemble within the initial energy levels, signaling, in this way, the establishment of a non-unitary gravity-induced thermal equilibrium.
Modern Physics Letters B, 2010
A new analogy between superfluid systems and cosmology is here presented, which relies strongly o... more A new analogy between superfluid systems and cosmology is here presented, which relies strongly on the following ingredient: the back-reaction of the vacuum to the quanta of sound waves. We show how the presence of thermal phonons, the excitations above the quantum vacuum for T > 0, enable us to deduce an hydrodynamical equation formally similar to the one obtained for a perfect fluid in a Universe obeying the Friedmann–Robertson–Walker metric.
Physica Scripta, 2019
It is explicitly shown that a one-family parameter model reproducing the nonlinear Newton-Schrod... more It is explicitly shown that a one-family parameter model reproducing the nonlinear Newton-Schrodinger
equation as the parameter goes to in nity is free from any causality violation problem for any nite value
of it. This circumstance arises from the intrinsic mechanism of spontaneous state reduction of the model,
absent in the Newton-Schrodinger limit. A speci c ideal EPR experiment involving a superposition of two
distinct CM's position states of a massive lump is analyzed, showing recovered compatibility with QM.
Besides, the new framework suggests a soft version of the Many Worlds Interpretation, in which the typical
indiscriminate proliferation of Everett branches, together with the bizarre inter-branches communications
made possible by nonlinearity, are strongly suppressed in the macroscopic world by the same mechanism of
state reduction.
Astrophys Space Sci, 2015
In this paper we present the discussion on the salient points of the computational analysis that ... more In this paper we present the discussion on the salient points of the computational analysis that are at the basis of the paper Rotation Curves of Galaxies by Fourth Order Gravity [1]. In fact in this paper any galactic component (bulge, disk and Dark matter component) required an onerous numerical computation since the Gauss theorem is not applicable in the Fourth Order Gravity. The computational and data analysis have been made with the software Mathematica .
Journal of Physics Communications
The result of a numerical simulation of two interacting particles in the framework of Nonunitary ... more The result of a numerical simulation of two interacting particles in the framework of Nonunitary Newtonian Gravity is presented here. Particles are held close together by a 3-d harmonic trap and interact with each other via an 'electrical' delta-like potential and via the ordinary Newtonian term, together with a fluctuational nonunitary counterpart of the latter. Fundamental nonunitarity can be seen as arising from the interaction of the physical degrees of freedom with (gravitational) hidden copies of them. Starting from an energy eigenstate within the ordinary setting, it is shown that, while energy expectation remains constant, a slow net variation of the von Neumann entropy for the system as a whole takes place, with a small modulation induced on the relative entanglement entropy of the two particles. Besides, the simulation shows explicitly how fundamental gravity-induced entropy can be clearly distinguished from the subjective notion of coarse-grained entropy, i.e. from the entropy of one particle with respect to the 'environment' of the other.
We investigate the radial behavior of galactic rotation curves by a Fourth Order Gravity adding a... more We investigate the radial behavior of galactic rotation curves by a Fourth Order Gravity adding also the Dark Matter component. The Fourth Order Gravity is a theory of Gravity described by Lagrangian generalizing the one of Hilbert Einstein containing a generic function of the Ricci scalar, the Ricci and Riemann tensor. A systematic analysis of rotation curves, in the Newtonian Limit of theory, induced by all galactic sub-structures of ordinary matter is shown. This analysis is presented for Fourth Order Gravity with and without Dark Matter. The outcomes are compared with respect to the classical outcomes of General Relativity. The gravitational potential of point-like mass is the usual potential corrected by two Yukawa terms. The rotation curve is higher or also lower than curve of General Relativity if in the Lagrangian the Ricci scalar square is dominant or not with respect to the contribution of the Ricci tensor square. The theoretical spatial behaviors of rotation curve are compared with the experimental data for the Milky Way and the galaxy NGC 3198. Although the Fourth Order Gravity gives more rotational contributions, in the limit of large distances the Keplerian behavior is ever present, and it is missing only if we add the Dark Matter component. However by modifying the theory of Gravity, consequently, also the spatial description of Dark Matter could undergo a modification and the free parameters of model can assume different values. After an analytical discussion of theoretical behaviors and the comparing with experimental evidence we can claim that any Fourth Order Gravity is not successful to explain the galactic rotation curves. In the last part of paper we analyze the gravitational potential induced by Lagrangian containing only powers of Ricci scalar. In this case we find an inconsistency in the boundary conditions in the passage from matter to the vacuum.
Phis. Rev. A, 2011
Aim of this work is to calculate explicitly the result of the experiment of superposition of a mi... more Aim of this work is to calculate explicitly the result of the
experiment of superposition of a mirror in the Michelson photon
cavities interferometric device proposed by Marshall, Simon,
Penrose and Bownmeester, as expected within a recently proposed
model of non-unitary self-gravity inducing localization. As for
other proposals of modifications of Quantum Mechanics in a
non-unitary sense, aimed to account for both unitary evolution and
irreversible collapse, like in the famous Ghirardi-Rimini-Weber
and Pearle's models, it turns out that, for the experimental
parameters proposed, no effect is detectable at all. It is pointed
out that the enhancing properties of matter granularity does not
substantially change this conclusion. Parameters have also been
exploratively varied in a certain range beyond the proposed
values. It is shown that within `sensible' parameters, that are
not yet attainable within current technology, the model exhibits a
peculiar signature with respect to other collapse models as far as
parameters space is explored. Besides, the calculation offers a
way to see non-unitary gravity at work in a quasi-realistic
setting.
The new formal analogy between superfluid systems and cosmology, which emerges by taking into acc... more The new formal analogy between superfluid systems and cosmology,
which emerges by taking into account the back-reaction of the
vacuum to the quanta of sound waves \cite{noi}, enables us to put
forward some common features between these two different areas of
physics. We find the condition that allows us to justify a General
Relativity (GR) derivation of the hydrodynamical equation for the
superfluid in a four-dimensional space whose metric is the Unruh
one \cite{Unruh}. Furthermore we show how, in the particular case
taken into account, our hydrodynamical equation can be deduced
within a four-dimensional space from the wave equation of a
massless scalar field.
A new analogy between superfluid systems and cosmology is here presented, which relies strongly o... more A new analogy between superfluid systems and cosmology is here
presented, which relies strongly on the following ingredient: the
back-reaction of the vacuum to the quanta of sound waves. We show
how the presence of thermal phonons, the excitations above the
quantum vacuum for T>0T> 0T>0, enable us to deduce an hydrodynamical
equation formally similar to the one obtained for a perfect fluid
in a Universe obeying the Friedmann-Robertson-Walker metric.
International Journal of Quantum Information, 2019
The quest for a microscopic foundation of Thermodynamics is addressed within the Nonunitary New-t... more The quest for a microscopic foundation of Thermodynamics is addressed within the Nonunitary New-tonian Gravity model through the study of a specific closed system, namely a three-dimensional harmonic nanocrystal. A numerical calculation of the nanocrystal von Neumann entropy as a function of time is performed, showing a sharp monotonic increase, followed by a stabilization at late times. This behavior is consistent with the emergence of a micro-canonical ensemble within the initial energy levels, signaling, in this way, the establishment of a non-unitary gravity-induced thermal equilibrium.