34,316 research outputs found
A square-torsion modification of Einstein-Cartan theory
In the present paper we consider a theory of gravity in which not only
curvature but also torsion is explicitly present in the Lagrangian, both with
their own coupling constant. In particular, we discuss the couplings to Dirac
fields and spin fluids: in the case of Dirac fields, we discuss how in our
approach, the Dirac self-interactions depend on the coupling constant as a
parameter that may even make these non-linearities manifest at subatomic
scales, showing different applications according to the value of the parameter
we have assigned; in the case of spin fluids, we discuss FLRW cosmological
models arising from the proposed theory.Comment: 21 page
On geometric relativistic foundations of matter field equations and plane wave solutions
In this paper, we start from the geometric relativistic foundations to define
the basis upon which matter field theories are built, and their wave solutions
are investigated, finding that they display repulsive interactions able to
reproduce the exclusion principle in terms of its effects in a dynamical way,
then discussing possible consequences and problems.Comment: 11 page
A torsional completion of gravity for Dirac matter fields and its applications to neutrino oscillations
In this paper, we consider the torsional completion of gravitation for an
underlying background filled with Dirac fields, applying it to the problem of
neutrino oscillations: we discuss the effects of the induced torsional
interactions as corrections to the neutrino oscillation mechanism.Comment: 4 page
Torsionally-gravitating charged matter fields and quanta
In the present article we shall consider the torsional completion of a
gravitational background that is filled with electrodynamically interacting
material fields, taken to be of fermionic type, eventually deriving properties
like the impossibility of singularities and the possibility of confinement,
both necessary for a correct quantum description.Comment: 7 page
A classical calculation of the leptonic magnetic moment
In this paper we will show that purely classical concepts based on a few
heuristic considerations about extended field configurations are enough to
compute the leptonic magnetic moment with corrections in -power
perturbative expansion.Comment: 5 page
Black (or) Italians? The Construction of Blackness in Italian Context - Past and Present
Black (or) Italians? The Construction of Blackness in the Italian Context – Past and Present.
In the last 30 years Italy experienced relevant changes due to its new configuration as a postcolonial country and land of transnational migrations, without ceasing to be an emigration country. From the official end of Italian colonialism and, later, from the Berlin Wall fell, the seas around Italy no longer constitute insuperable barriers but rather borders that are continously crossed. The arrival, the transition or the stable settlement of people coming from the Global South, the daily deaths in the Mediterranean Sea, the increasing presence of the so-called “second generations of migration” and the consequent social and demographic changes force Italy to deal with its postcolonial and, as Cristina Lombardi-Diop proposed, postracial status. The new social balances created by migration flows and the increasingly presence of Afroitalians have two simultaneous effects: on one hand they are re-defining the concepts of “being Italian” and of national belonging; on the other hand they are revealing that the racial identity of the Italians has been built up as uniformly white, with the consequent foreclosure of people who are not included in this “chromatic norm”.
In this paper I focus on the construction processes of blackness in the frame of Italian historical and geopolitical context. Connecting the postcolonial present with the colonial past, I examine how the definition of the concept of blackness has been influenced by specific social phenomena linked to specific historical periods (as colonialism, migrations etc). I analyze both the representations of blackness in today’s Italy and how the common idea that “black Italian” is an oxymoron is increasingly challenged by the “second generations”
Polar solutions with tensorial connection of the spinor equation
Dirac field equations are studied for spinor fields without any external
interaction and when they are considered on a background having a tensorial
connection with a specific non-vanishing structure some solution can be found
in polar form displaying a square-integrable localized behaviour.Comment: 6 page
Torsion Gravity for Dirac Fields
In this article we will take into account the most complete back-ground with
torsion and curvature, providing the most exhaustive coupling for the Dirac
field: we will discuss the integrability of the interaction of the matter field
and the reduction of the matter field equations.Comment: 7 page
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