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At least 937 records · Page 52Linked to original sources
arXiv2014

Vacuum quantum fluctuation energy in expanding universe and dark energy

This article is based on the Planckon densely piled vacuum model and the principle of cosmology. With the Planck era as initial conditions and including the early inflation, we have solved the Einstein-Friedmann equations to describe the evolution of the universe. The results are: 1) the ratio of the dark energy density to the vacuum quantum fluctuation energy density is $\frac{{{ρ}_{de}}}{{{ρ}_{vac}}}\sim{{(\frac{{{t}_{P}}}{{{T}_{0}}})}^{2}}\sim{{10}^{-122}} $; 2) at the inflation time ${{t}_{\inf }}={{10}^{-35}}s$, the calculated universe radiation energy density is $ρ({{t}_{\inf }})\sim{{10}^{-16}}{{ρ}_{vac}}$ and the corresponding temperature is ${{E}_{c}}\sim{{10}^{15}}GeV$ consistent with the GUT phase transition temperature; 3) the expanding universe with vacuum as its environment is a non-equilibrium open system constantly exchanging energy with vacuum; during its expansion, the Planckons in the universe lose quantum fluctuation energy and create the cosmic expansion quanta-cosmons, the energy of cosmons is the lost part of the vacuum quantum fluctuation energy and contributes to the universe energy with the calculated value ${{E}_{\cos mos}}={{10}^{22}}{{M}_{\otimes }}{{c}^{2}}$ (where ${{M}_{\otimes }}$ is solar mass); 4) the total energy of the universe, namely the negative gravity energy plus the positive universe energy is zero; 5) the negative gravity potential and the gravity acceleration related to the creation of cosmons are derived with the nature of outward repulsive force, indicating that the cosmon may be the candidate of the dark energy quantum; 6) both the initial Planck era solution and the infinite asymptotic solution of the Einstein-Friedman equations are unstable: the former tends to expand and the latter tends to shrink, so that the Einstein-Friedman universe will undergo a cyclic evolution of successive expansion and shrinking.

physics.gen-ph↗
arXiv2013

On the Metric of Space-time

Maxwell's equations are obeyed in a one-parameter group of isotropic gravity-free flat space-times whose metric depends upon the value of the group parameter. An experimental determination of this value has been proposed. If it is zero, the metric is Minkowski's. If it is non-zero, the metric is not Poincare invariant and local frequencies of electromagnetic waves change as they propagate. If the group parameter is positive, velocity independent red shifts develop and the group parameter plays a role similar to that of Hubble's constant in determining the relation of these redshifts to propagation distance. In the resulting space-times, the velocity dependence of Doppler shifts is a function of propagation distance. If the group parameter and Hubble's constant have the same order of magnitude, observed frequency shifts in radiation received from stellar sources can imply source velocities quite different from those implied in Minkowski space. In these space-times, electromagnetic waves received from bodies in galactic Kepler orbits undergo frequency shifts which are indistinguishable from shifts currently attributed to dark matter and dark energy in Minkowski space, or to a non-Newtonian physics.

physics.gen-ph↗
arXiv2013

Solar Coronal Heating and Limb Effect

The quiet solar coronal heating problem and the observed center-to-limb wavelength variations of the solar lines (limb effect) can be explained. In this paper the quantitative calculations for these two phenomena are presented.

physics.gen-ph↗
arXiv2013

Quarks and leptons which might be composite

An option of composite quarks and leptons is briefly outlined, where elementary color-triplet quark-like fermions are bound with an elementary color-triplet isoscalar scalar boson due to the color coupling 3* x 3* -> 3 and 3* x 3 -> 1, respectively.

physics.gen-ph↗
arXiv2013

Constraints on the general solutions of Einstein cosmological equations by Hubble parameter times cosmic age: a historical perspective

In a historical perspective, compact solutions of Einstein's equations, including the cosmological constant and the curvature terms, are obtained, starting from two recent observational estimates of the Hubble's parameter (H0) and the "age" of the universe (t0). Cosmological implications for ΛCDM (Λ Cold Dark Matter), KOFL (k Open Friedman-Lemaitre), plus two mixed solutions are investigated, under the constraints imposed by the relatively narrow current uncertainties. Quantitative results obtained for the KOFL case seem to be compatible with matter density and the highest observed red-shifts from distant galaxies, while those obtained for the ΛCDM may be more difficult to reconcile.

physics.gen-ph↗
arXiv2013

Climate variability according to triple saros gravity cycles

I describe a climate model which corresponds directly to eclipse cycles. The theory is based upon a similarity between the 54 year triple saros eclipse period and the periodicity of drought. I argue that eclipse shadows are an indication of gravity cycles, and that variable lunar gravitation is the most significant aspect of the eclipse process. I reinforce the idea that lunar gravitational forcing has a profound effect on the water vapor in Earth's atmosphere, and can affect the density and location of clouds. I explore the possibility that decadal variability of ocean surface levels may be explained by triple saros gravity cycles. I point out that lunar gravitation was excluded from the most significant climate report of 2007, and that climate data contradictions have been overlooked by researchers. I focus on the value of data that has not been aggregated into global averages. I touch upon the history of global warming, and I offer predictions based upon 54 year climate periodicity.

physics.gen-ph↗
arXiv2013

The 5D to 4D projection model applied as a Lepton to Galaxy Creation model

The 5D to 4D projection is presented in a simple geometry giving the Perelman Theorem, resulting in a 3D doughnut structure for the space manifold of the Lorentz space-time. It is shown that in the lowest quantum state, this Lorentz manifold confines and gives the de Broglie leptons from the massless 5D e-trinos. On the scale of the universe, it allows for a model for the creation of galaxies.

physics.gen-ph↗
arXiv2013

Laser-induced synthesis and decay of Tritium under exposure of solid targets in heavy water

The processes of laser-assisted synthesis of Tritium nuclei and their laser-induced decay in cold plasma in the vicinity of solid targets (Au, Ti, Se, etc.) immersed into heavy water are experimentally realized at peak laser intensity of 10E10-10E13 Watts per square centimeter. Initial stages of Tritium synthesis and their laser-induced beta-decay are interpreted on the basis of non-elastic interaction of plasma electrons having kinetic energy of 5-10 eV with nuclei of Deuterium and Tritium, respectively.

physics.gen-ph↗
arXiv2013

A dark energy with higher order derivatives of $H$ in the modified gravity $f(R,T)$

In this paper, we consider a recently proposed model of Dark Energy (DE) which contains three terms (one proportional to the squared Hubble parameter, one to the first derivative with respect to the cosmic time of the Hubble parameter and one proportional to the second derivative with respect to the cosmic time of the Hubble parameter) in the light of the $f\left(R,T \right)$ model of modified gravity, considering the particular model $f\left(R,T \right) = μR + νT$, with $μ$ and $ν$ two free positive constant parameters. Here $R$ and $T$ are the curvature and torsion scalars, respectively. In this work, we have found that the Hubble parameter $H$ exhibits a decaying behavior until redshifts of the order of $z\approx-0.5$ (when it starts to increase) and the time derivative of the Hubble parameter goes from negative to positive values for different redshifts. The equation of state (EoS) parameter of DE and the effective EoS parameter exhibit a transition from $ω<-1$ to $ω>-1$ (then the EoS parameters have a quintom-like behavior). We have also found that the said model can attain the late time accelerated phase of the universe. Using the statefinder parameters $r$ and $s$, we derived that the considered model can attaining the $Λ$CDM phase of the universe and can interpolate between dust and $Λ$CDM phase of the universe. Finally, studying the squared speed of sound $v_s^2$, we have seen that the model under consideration is classically stable in the earlier stage of the universe, but classically unstable in the current stage.

physics.gen-ph↗
arXiv2013

Induction of gravity and strong interactions on non-associative algebra

In this work we take view on space-time as dual representation of fields on manifold. Given we accept such view, the space of functions in operator representation becomes probability amplitudes f(x) of a particle. Since the probabilistic interpretation of f(x) module follows from f(x) and f*(x) duality, the problem of finding representation of wave function reduces to Frobenius theorem for division algebras. We then construct the gravity model and the model of strong interactions as a logical implication of the extension of fields interaction algebra to non-associative algebra of octonions. The application of Penrouse approach in spinor representation of space-time combined with the proposed approach further leads us to chirality of interactions and absence of right neutrino and left spinors in singleton state. We also show the obtained model is consistent with general theory of relativity and SU(3) for distances larger than Planck length. The obtained model also contains the generalization of general theory of relativity to the model with torsion given the chirality of the field. Importantly, the application of our approach gives us Einstein equation with gravity constant equal to squared Planck mass as consequence of non-associativity of interactions fields. We construct strong interaction model based on matrix representation of octonion algebra with special multiplication rule. The strong interaction is induced by vector fields of octonion algebra with constant gravity force, which is in turn induced by a pair of charged $W$ vector bosons from standard theory of weak interactions. The problem of quark confinement is presented as a spinor solution inside "black hole".

physics.gen-ph↗
arXiv2013

What is a photon?

We discuss the absorber theory of radiation as put forward by Wheeler and Feynman. We show that it gives a better understanding of the photon compared to the usual quantum electrodynamics (QED) picture.

physics.gen-ph↗
arXiv2013

Macroscopic quantum-type potentials in scale relativity

We review in this paper the use of the theory of scale relativity and fractal space-time as a tool particularly well adapted to the possible development of a future genuine theoretical systems biology. We emphasize in particular the concept of quantum-type potentials, since in many situations the effect of the fractality of space -- or of the underlying medium -- amounts to the addition of such a potential energy to the classical equations of motion. Various equivalent representations -- geodesic, quantum, fluid mechanical, stochastic -- of these equations are given, as well as several forms of generalized quantum potentials. Examples of their possible intervention in high critical temperature superconductivity and in turbulence are also described, since some biological processes may be analog in some aspects to these physical phenomena. These potential energy extra contributions could have emerged in biology from the very fractal nature of the medium, or from an evolutive advantage, since they involve spontaneous properties of self-organization, morphogenesis structuration and multi-scale integration.

physics.gen-ph↗
arXiv2013

False vacuum as an unstable state: possible cosmological implications

Recent LHC results concerning the mass of the Higgs boson indicate that the vacuum in our Universe may be unstable. We analyze properties of unstable vacuum states from the point of view of the quantum theory of unstable states. From the literature it is known that some of false vacuum states may survive up to times when their survival probability has a non-exponential form. At times much latter than the transition time, when contributions to the survival probability of its exponential and non-exponential parts are comparable, the survival probability as a function of time $t$ has an inverse power-like form. We show that at this time region the instantaneous energy of the false vacuum states tends to the energy of the true vacuum state as $1/t^{2}$ for $t \to \infty$. Properties of the instantaneous energy at transition times are also analyzed for a given model. It is shown that at this time region large and rapid fluctuations of the instantaneous energy take place. This suggests analogous behavior of the cosmological constant at these time regions.

physics.gen-ph↗
arXiv2013

A critical value for dark energy

Experimental evidence over a number of recent years has shown the density parameter of the universe omega converging to the critical value of 1, which defines a flat, Euclidean universe. No such calculations have defined a critical value for the most significant component of omega, that for the dark energy, omega lambda, but the new data provided by the Planck probe open up the previously unconsidered possibility that a particular value with special physical significance occurs at omega lambda = 2/3. If future observations should converge on exactly this value, then we may have the first indication that the explanation for this phenomenon lies in necessary constraints provided by fundamental laws of physics on possible cosmologies for the universe.

physics.gen-ph↗
arXiv2013

Layer-multiplicity as a community order-parameter

A small number of (perhaps only 6) broken-symmetries, marked by the edges of a hierarchical series of physical {\em subsystem-types}, underlie the delicate correlation-based complexity of life on our planet's surface. Order-parameters associated with these broken symmetries might in the future help us broaden our definitions of community health. For instance we show that a model of metazoan attention-focus, on correlation-layers that look in/out from the 3 boundaries of skin, family & culture, predicts that behaviorally-diverse communities require a characteristic task layer-multiplicity {\em per individual} of only about $4 \frac14$ of the six correlation layers that comprise that community. The model may facilitate explorations of task-layer diversity, go beyond GDP & body count in quantifying the impact of policy-changes & disasters, and help manage electronic idea-streams in ways that strengthen community networks. Empirical methods for acquiring task-layer multiplicity data are in their infancy, although experience-sampling via cell-phone button-clicks might be one place to start.

physics.gen-ph↗
arXiv2013

Synchronized clocks and time on a rotating disc

Basic for the definition of 'time' are clocks operating under stationary conditions. The periods of two clocks can be compared with each other via two return experiments. The central clock mediates between the rotating and the inertial frame. Dimensional arguments and a detailed deduction show that the period of a rotating clock, measured externally in the inertial system, is the same as the internally defined one. There is a common synchron-time, especially 'absolute' simultaneity and invariance of flight times hold. This allows a new discussion of the twin problem. The invariance of a rotating circle allows the transference of the inertial polar coordinates to the rotating plane. The flight time of a light pulse obeys a generalized Fermat's principle. If rays are well defined, this time of flight determines the phase shift of the wave and the result of interference experiments. All general considerations and proofs are independent of the relativity theory, especially of the concept of local inertial systems and differential-geometrical techniques.

physics.gen-ph↗