Abstract:
The Hamiltonian associated to the mass variable system is constructed from first principles through finding a constant of motion of the system. A comparison is made of the classical motion of a body with its mass position depending in the (x,v) space and (x,p) space which are defined by the constant of motion and the Hamiltonian, for a particular model of mass variation. As one could expected, these motion looks different on these spaces. The quantization of the harmonic oscillator with this mass variation is done, and a comparison is made by using the usual Hamiltonian approach with the proposed quantization of the constant of motion approach. This comparison is done at first order in perturbation theory, and one sees a difference between both approaches which can, in principle, be measured.

Abstract:
We study the phenomenon of decoherence during the operation of one qubit transformation, controlled-not (CNOT) and controlled-controlled-not (C^{2}NOT) quantum gates in a quantum computer model formed by a linear chain of three nuclear spins system. We make this study with different type of environments, and we determine the associated decoherence time as a function of the dissipative parameter. We found that the dissipation parameter to get a well defined quantum gates (without significant decoherence) must be within the range of . We also study the behavior of the purity parameter for these gates and different environments and found linear or quadratic decays of this parameter depending on the type of environments.

We make a numerical study of decoherence on the teleportation algorithm implemented in a linear chain of three nuclear spins system. We study different types of environments, and we determine the associated decoherence time as a function of the dissipative parameter. We found that the dissipation parameter to get a well defined quantum gates (without significant decoherence) must be within the range of γ≤4×10^{-4} for not thermalized case, which was determined by using the purity parameter calculated at the end of the algorithm. For the thermalized case the decoherence is stablished for very small dissipation parameter, making almost not possible to implement this algorithm for not zero temperature.

By removing a ^{12}C atom from the tetrahedral
configuration of the diamond, replacing it by a ^{13}C atom, and repeating
this in a linear direction, it is possible to have a linear chain of nuclear
spins one half and to build a solid state quantum computer. One qubit rotation,
controlled-not (CNOT) and controlled-controlled-not (CCNOT) quantum gates are
obtained immediately from this configuration. CNOT and CCNOT quantum gates are
used to determined the design parameters of this quantum computer.

Abstract:
Classical
chaotic behavior in diatomic molecules is studied when chaos is driven by a
circularly polarized resonant electric field and expanding up to fourth order
of approximation the Morse’s potential and angular momentum of the system. On
this double resonant system, we find a weak and a strong stationary (or
critical) points where the chaotic characteristics are different with respect to
the initial conditions of the system. Chaotic behavior around the weak critical
point appears at much weaker intensity on the electric field than the electric
field needed for the chaotic behavior around the strong critical point. This
classical chaotic behavior is determined through Lyapunov exponent, separation
of two nearby trajectories, and Fourier transformation of the time evolution of
the system. The threshold of the amplitude of the electric field for appearing
the chaotic behavior near each critical point is different and is found for
several molecules.

Abstract:
We propose a mathematical model for
determining the probability of meteorite origin, impacting the earth. Our
method is based on axioms similar to both the complex networks and emergent
gravity. As a consequence, we are able to derive a link between complex
networks and Newton’s gravity law, and as a possible application of our model
we discuss several aspects of the Bacubirito meteorite. In particular, we
analyze the possibility that the origin of this meteorite may be alpha Centauri
system. Moreover, we find that in order for the Bacubirito meteorite to come
from alpha Cen and be injected into our Solar System, its velocity must be
reduced one order of magnitude of its ejected scape velocity from alpha Cen.
There are several ways how this could happened, for example through collision
with the Oort cloud objects (located outside the boundary of our Solar System),
and/or through collisions within the Solar meteorites belt (located between
Mars and Jupiter). We also argue that it may be interesting to study
the Bacubirito meteorite from the perspective of the recently discovered Oumuamua
object.

Abstract:
We develop in the weak coupling approximation a quasi-non-Markovian master equation and study the phenomenon of decoherence during the operation of a controlled-not (CNOT) quantum gate in a quantum computer model formed by a linear chain of three nuclear spins system with second neighbor Ising interaction between them. We compare with the behavior of the Markovian counterpart for temperature different from zero (thermalization) and at zero temperature for low and high dissipation rates. At low dissipation there is a very small difference between Markovian and quasi no-Markovian at any temperature which is unlikely to be measured, and at high dissipation there is a difference which is likely to be measured at any temperature.

Abstract:
A new approach to radiation reaction for the correction of the linear and circular motion of a charged particle takes into account the emission of electromagnetic radiation due to its acceleration. This new formulation was based on expressing the radiation reaction force in terms of the external force rather than the acceleration of the charge. In this paper, a generalization of the radiation reaction force in terms of the external force approach is formulated for any arbitrary motion of the charged particle. This generalization includes the linear and circular acceleration cases previously investigated.

Abstract:
For explicitly time depending mass density which
satisfies a continuity equation, it is shown that Maxwell-like equations for
gravitational field follow naturally without any need of General Relativity
Theory approximation or related assumptions. As a consequence, it is shown that
several features already known in Electrodynamics (Poynting vector, density of
energy, tensor stress, and radiation) are totally reproduced for gravitational
field.