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Marcelo Samuel Berman

Publications and source records attributed to Marcelo Samuel Berman.

34 records · Page 2Linked to original sources

Is the Universe a White-Hole?

Pathria(1972) has shown, for a pressureless closed Universe, that it is inside a black (or white) hole. We show now, that the Universe with a cosmic pressure obeying Einstein's field equations, can be inside a white-hole. In the closed case, a positive cosmological constant does the job; for the flat and open cases, the condition we find is not verified for the very early Universe, but with the growth of the scale-factor, the condition will be certainly fulfilled for a positive cosmological constant, after some time. We associate the absolute temperature of the Universe, with the temperature of the corresponding white-hole.

physics.gen-ph↗

The Pioneer Anomaly and a Machian Universe

We discuss astronomical and astrophysical evidence, which we relate to the principle of zero-total energy of the Universe, that imply several relations among the mass M, the radius R and the angular momentum L of a "large" sphere representing a Machian Universe. By calculating the angular speed, we find a peculiar centripetal acceleration for the Universe. This is an ubiquituous property that relates one observer to any observable. It turns out that this is exactly the anomalous acceleration observed on the Pioneers spaceships. We have thus, shown that this anomaly is to be considered a property of the Machian Universe. We discuss several possible arguments against our proposal.

physics.gen-ph↗

Shear and Vorticity in a Combined Einstein-Cartan-Brans-Dicke Inflationary Lambda-Universe

A combined BCDE (Brans-Dicke and Einstein-Cartan) theory with lambda-term is developed through Raychaudhuri's equation, for inflationary scenario. It involves a variable cosmological constant, which decreases with time, jointly with energy density, cosmic pressure, shear, vorticity, and Hubble's parameter, while the scale factor, total spin and scalar field increase exponentially. The post-inflationary fluid resembles a perfect one, though total spin grows, but the angular speed does not (Berman, 2007d). Keywords: Cosmology; Einstein; Brans-Dicke; Cosmological term; Shear; Spin; Vorticity; Inflation; Einstein-Cartan; Torsion. PACS: 04.20.-q ; 98.80.-k ; 98.80.Bp ; 98.80.Jk

physics.gen-ph↗

A General Relativistic Rotating Evolutionary Universe

We show that when we work with coordinate cosmic time, which is not proper time, Robertson-Walker's metric, includes a possible rotational state of the Universe. An exact formula for the angular speed and the temporal metric coefficient, is found.

physics.gen-ph↗

A General Relativistic Rotating Evolutionary Universe - Part II

As a sequel to (Berman, 2008a), we show that the rotation of the Universe can be dealt by generalised Gaussian metrics, defined in this paper. Robertson-Walker's metric has been employed with proper-time, in its standard applications; the generalised Gaussian metric imply in the use of a non-constant temporal metric coefficient modifying Robertson-Walker's standard form. Experimental predictions are made

physics.gen-ph↗

Shear and Vorticity in an Accelerating Brans-Dicke Lambda-Universe with Torsion

We study accelerating Universes with power-law scale-factors. We include shear and vorticity, a cosmological "constant" term, and spin from torsion, as in Einstein-Cartan's theory when a scalar-field of Brans-Dicke type acts in the model. We find a "no-hair" result, for shear and vorticity; we also make contact with the alternative Machian picture of the Universe. Keywords: Cosmology; Einstein; Brans-Dicke; Cosmological term; Shear; Spin; Vorticity; Inflation; Einstein-Cartan; Torsion; Accelerating Universe

physics.gen-ph↗

On the Rotational and Machian Properties of the Universe

We find a Classical explanation on the origin of the Cosmological "constant" term, as a rotating feature of the Universe. We give a picture on "creation" of the Universe. By analogy with the original Brans-Dicke relation, several other similar relations were obtained in a previous paper (Berman, 2007d), which we now extend, by relating the angular momentum L, absolute temperature T, and the cosmological "constant", with R, where R, M stand for the radius (scale-factor) and the mass of the causally related Universe. We show here that these properties, which characterize Machian Universes, can be put in the form of equalities, which can be derived, from the conjecture that the total energy of the Universe is null, alike with the effective energy density, and we therefore imply that R depends linearly with M ; the angular momentum runs like squared R ; T, like R to the power -1/2 ; lambda, as R to the power -2 so that the total entropy of the Universe grows with R to the power 3/2, and, then, also as M to the power 3/2. The "loss of information paradox", for black holes, is dismantled. It must be obvious, from this paper, that each type of energy contribution, to the total energy of the Universe, divided by M multiplied by c-squared, yields a constant, during all times, so that, for instance, if the present contribution of the cosmological "constant", drives the present Universe, it also must have driven alike, in all the lifespan of the Machian Universe: the relative contributions of densities of each kind, towards the total density, remain the same during all times. Berman (2008; 2008a; 2008b) found similar hidden rotational states of the Universe in Relativistic theories which obey Robertson-Walker's metric.

physics.gen-ph↗

Are Mass and Length Quantized?

We suggest that there are time-varying quanta of mass (gomidia) and of length (somia), thus pointing to a quantization of geometry and gravitation. The present numerical value of the gomidium and somium, are, 10 to the power minus 65 grams, and 10 to the power minus 91 centimeters. Gomidia may be responsible for dark matter in the Universe; Heisenberg's principle, confirms the numerical estimates for gomidia and somia, either for the present Universe, or for Planck's time.

physics.gen-ph↗

Natural Entropy Production in an Inflationary Model for a Polarized Vacuum

Though entropy production is forbidden in standard FRW Cosmology, Berman and Som presented a simple inflationary model where entropy production by bulk viscosity, during standard inflation without ad hoc pressure terms can be accommodated with Robertson-Walker's metric, so the requirement that the early Universe be anisotropic is not essential in order to have entropy growth during inflationary phase, as we show. Entropy also grows due to shear viscosity, for the anisotropic case. The intrinsically inflationary metric that we propose can be thought of as defining a polarized vacuum, and leads directly to the desired effects without the need of introducing extra pressure terms.

physics.gen-ph↗

On the Magnetic Field, and Entropy Increase, in a Machian Universe

By means of the experimental result on the present equipartition between background microwave radiation energy and that of the interstellar magnetic field, and by advancing a Machian relation for the magnetic field, which, differently than in other authors' papers, is valid for the entire spanlife of the Universe, implying that the magnetic field depends on the inverse radius of the Universe, we obtain a general formula such that B depends on the inverse of R . Our estimate for Planck's magnetic field is (1/1000) times the Sabbata and Sivaram's one. It is shown that the energy densities involved in the above problem are dependent on the inverse square of R . For radiation, this implies, as we show, that the total entropy of the Universe is increasing with expansion. In particular we show that R depends on the inverse square of T, where T is the absolute temperature, and the entropy is proportional to the 3/2 power of R .

physics.gen-ph↗

On a Time Variation of Neutrino's Mass

After the introduction to the subject, we review the Machian relations involving the different kinds of energy densities in the Universe. By suposing that dark-matter is composed by Neutrino's massive energy, we hint that the Neutrino's masses should be proportional to the inverse of R, while the total number of Neutrinos in the Universe increases with the square of R, where R stands for Hubble's length. This makes possible that the dark mater-energy density be of Neutrinos origin, to vary with the inverse square of R, as is necessary for a Machian Universe. The neutrino average mass is estimated for the present Universe (=10 to the minus 76 power, in grams).

physics.gen-ph↗

Cosmological Model for the Very Early Universe in B.D. Theory

Following a paper by Berman and Marinho Jr (2001), where it was established an equation of state (p=-(1/3)rho), for the very early Universe, under which, Einstein's equations with lambda=0, render a scale-factor proportional to the time coordinate, and under which, Berman(2006, 2006a) showed that in the non-null lambda case, the Universe entered automatically into an exponential inflationary phase, we now study the corresponding effect in Brans-Dicke Cosmology. We find that the resulting models are similar to those in General Relativity Cosmology.

gr-qc↗

Brief History of Black-Holes

We show that the gravitational collapse of a black-hole terminates in the birth of a white-hole, due to repulsive gravitation (antigravitation); in particular, the infinite energy density singularity does NOT occur.

gr-qc↗

Energy of Kerr-Newman Black-Holes and Gravitomagnetism

New formulae are obtained for the energy of K.N. b.h.'s that point out a gravitomagnetic energy effect. The results are valid for slowly or rapidly rotating black-holes. The expression of the energy density of Kerr-Newman back-holes in the slow rotation case, is obtained afterwards, and shown to be essentially positive. Subsequently,we show how to attain a "repulsive" gravitation (antigravitation) state identified with negative energy distribution contents in a limited region of space, without violating the Positive Energy Theorem.

gr-qc↗