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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    International journal of theoretical physics 39 (2000), S. 1375-1396 
    ISSN: 1572-9575
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract A new general-relativistic theory of cosmology, the dynamical variables of whichare those of Hubble's, namely distances and redshifts, is presented. The theorydescribes the universe as having a three-phase evolution with a deceleratingexpansion followed by a constant and an accelerating expansion, and it predictsthat the universe is now in the latter phase. The theory is actually a generalizationof Hubble's law taking gravity into account by means of Einstein's theory ofgeneral relativity. The equations obtained for the universe expansion are elegantand very simple. It is shown, assuming Ω0 = 0.24, that the time at which theuniverse goes over from a decelerating to an accelerating expansion, i.e., theconstant expansion phase, occurs at 0.03 τ from the big bang, where τ is theHubble time in vacuum. Also, at that time the cosmic radiation temperature was11 K. Recent observations of distant supernovae imply, in defiance of expectations,that the universe's growth is accelerating, contrary to what has always beenassumed, that the expansion is slowing down due to gravity. Our theory confirmsthese recent experimental results by showing that the universe now is definitelyin a stage of accelerating expansion.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    International journal of theoretical physics 38 (1999), S. 1993-2007 
    ISSN: 1572-9575
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract In this paper we review cosmological relativity,a new special theory of relativity that was recentlydeveloped for cosmology, and discuss in detail some ofits aspects. We recall that in this theory it is assumed that gravitation is negligible.Under this assumption, the receding velocities ofgalaxies and the distances between them in the Hubbleexpansion are united into a four-dimensionalpseudo-Euclidean manifold, similarly to space and time inordinary special relativity. The Hubble law is assumedand is written in an invariant way that enables one toderive a four-dimensional transformation which issimilar to the Lorentz transformation. The parameter inthe new transformation is the ratio between the cosmictime to the Hubble time (in which the cosmic time ismeasured backward with respect to the present time). Accordingly, the new transformationrelates physical quantities at different cosmic times inthe limit of weak or negligible gravitation. Thetransformation is then applied to the problem of the expansion of the universe at the very earlystage when gravity was negligible and thus thetransformation is applicable. We calculate the ratio ofthe volumes of the universe at two different timesT1 and T2 after the big bang. Under theassumptions that T2 – T1≈ 10-32 sec and T2 ≪ 1 sec,we find that V2/V1 =10-16/√T1. For T1≈ 10-132 sec we obtainV2/V1 ≈ 1050. Thisresult conforms with the standard inflationary universe theory, but now it isobtained without assuming that the universe is propelledby antigravity. New applications of the theory arepresented. This includes a new law for the decay of radioactive materials that was recentlydeveloped by Carmeli and Malin. The new law is amodification of the standard exponential formula whencosmic times are considered instead of the ordinarylocal times. We also show that there is no need to assumethe existence of galaxy dark matter; the Tully-Fisherlaw is derived from our theory. A significant extensionof the theory to cosmology that was recently made by Krori, Pathak, Das, and Purkayastha isgiven. In this way cosmological relativity becomes ageneral theory of relativity in seven dimensions ofcurved space-time-velocity. The solutions of the field equations in seven dimensions obtained by Kroriet al. are given and compared to those of the standardFriedmann-Robertson-Walker result. A completely newpicture of the expanding universe is thus obtained and compared to the FRW one.
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    International journal of theoretical physics 38 (1999), S. 2009-2014 
    ISSN: 1572-9575
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract An amended formula for the decay of radioactivematerial is presented. It is a modification of thestandard exponential formula. The new formula appliesfor long cosmic times comparable to the Hubble time. It reduces to the standard formula for shorttimes. It is shown that the material decays faster thanexpected. The application of the new formula to directmeasurements of the age of the universe and its implications are briefly discussed.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    International journal of theoretical physics 37 (1998), S. 2615-2620 
    ISSN: 1572-9575
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract A new approach to quantize the gavitationalfield is presented. It is based on the observation thatthe quantum character of matter becomes more significantas one gets closer to the big bang. As the metric loses its meaning, it makes sense to considerSchrodinger's three generic types of manifolds —unconnected differentiable, affinely connected, andmetrically connected — as a temporal sequencefollowing the big bang. Hence one should quantize thegravitational field on general differentiable manifoldsor on affinely connected manifolds. The SL(2,C) gaugetheory of gravitation is employed to explore thispossibility. Within this framework, the quantization itselfmay well be canonical.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    International journal of theoretical physics 37 (1998), S. 2621-2625 
    ISSN: 1572-9575
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract We describe the motion of a particle in acentral field in an expanding universe. Use is made ofa double expansion in 1/c and 1/τ, where c and τare the speed of light and the Hubble time. In thelowest approximation the rotational velocity is shownto satisfy v4 = 2/3 GMcH0, whereG is Newton's gravitational constant, M is the mass ofthe central body (galaxy), and H0 is theHubble constant. This formula satisfies observations of stars moving inspiral and elliptical galaxies, and is in accordancewith the familiar Tully–Fisher law.
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  • 6
    Electronic Resource
    Electronic Resource
    Springer
    International journal of theoretical physics 39 (2000), S. 1397-1404 
    ISSN: 1572-9575
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract For disk galaxies the fourth power of the circular velocity ν4 c of stars around thecore of the galaxy is proportional to the luminosity L, ν4 c ∝ L (Tully—Fisher law).Since L is proportional to the mass M of the galaxy, it follows that ν4 c ∝ M.Newtonian mechanics, however, yields ν2 c = GM/r for a circular motion. In orderto rectify this big difference, astronomers assume the existence of dark matter.We derive the equation of motion of a star moving in the central field of a galaxyand show that, for a circular motion, it yields a term of the form ν4 c ∝ GMc/τ,where G is Newton's gravitational constant, c is the speed of light, and τ is theHubble time. This puts in doubt the existence of halo dark matter for galaxies.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Foundations of physics 14 (1984), S. 923-924 
    ISSN: 1572-9516
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Springer
    General relativity and gravitation 3 (1972), S. 317-323 
    ISSN: 1572-9532
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract The gravitational field equations of general relativity theory are cast into a Yang-Mills-type theory by use of the group SL(2,C). The spin coefficients take the rôle of the Yang-Mills-like potentials, whereas the Riemann tensor takes the rôle of the fields. Comparison of this formalism with that of Utiyama and Kibble who related invariance under the Lorentz and the Poincaré groups to the existence of the gravitational field, is discussed
    Type of Medium: Electronic Resource
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  • 9
    Publication Date: 1977-08-29
    Print ISSN: 0031-9007
    Electronic ISSN: 1079-7114
    Topics: Physics
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  • 10
    Publication Date: 1972-12-01
    Print ISSN: 0001-7701
    Electronic ISSN: 1572-9532
    Topics: Physics
    Published by Springer
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