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A Possible Alternative to the Accelerating Universe III
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作者 Frank R. Tangherlini 《Journal of Modern Physics》 2016年第13期1829-1844,共16页
This work extends the author’s two previous works (2015), Journal of Modern Physics, 6, 78-87, and 1360-1370, by obtaining the index of refraction n of the dark energy for additional values of the cosmological densit... This work extends the author’s two previous works (2015), Journal of Modern Physics, 6, 78-87, and 1360-1370, by obtaining the index of refraction n of the dark energy for additional values of the cosmological density parameters, and for the two methods of obtaining n: least squares fit, and electromagnetic theory. Comparison of the alternative model with the accelerating universe for the new values of the density parameters and n is given in two tables. The new values for n are used to obtain a range of ages for the Einstein de Sitter (EdS) universe. It is shown that the EdS universe must be older than the comparison accelerating universe. This requirement is met for the Planck 2015 value of the Hubble constant, corrected for the speed of light reduction by n. A supporting measurement as well as a disagreeing measurement is also discussed. Possible support from a stellar age determination is also discussed. It is shown that the expression obtained earlier for the increased apparent magnitude of the SNe Ia provides as good a fit for a closed universe with Ω(tot = 1.005) , as it does for the flat EdS universe. Comparison is presented in a third table. An upper bound on Ω<sub>Λ</sub> is given for a closed universe that eventually collapses back on itself that is too small for the value needed for the accelerating universe. 展开更多
关键词 Dark Energy Speed of Light Age of universe closed universe
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Predicting the Curvature of the Cosmos, and Point of Volume Contraction in a Big Bounce Scenario
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作者 Christopher Pilot 《International Journal of Astronomy and Astrophysics》 2021年第2期265-278,共14页
Based on the latest Planck surveys, the universe is close to being remarkably flat, and yet, within observational error, there is still room for a slight curvature. If the curvature is positive, then this would lead t... Based on the latest Planck surveys, the universe is close to being remarkably flat, and yet, within observational error, there is still room for a slight curvature. If the curvature is positive, then this would lead to a closed universe, as well as allow for a big bounce scenario. Working within these assumptions, and using a simple model, we predict that the cosmos may have a positive curvature in the amount, <span style="white-space:nowrap;"><span style="white-space:nowrap;">Ω<sub>0</sub>=1.001802</span></span>, a value within current observational bounds. For the scaling laws associated with the density parameters in Friedmann’s equations, we will assume a susceptibility model for space, where, <img src="Edit_18751d6f-dbfa-47ba-be7c-8298073a34fd.png" alt="" style="white-space:normal;" />, equals the smeared cosmic susceptibility. If we allow the <img src="Edit_18751d6f-dbfa-47ba-be7c-8298073a34fd.png" alt="" /> to <em>decrease with increasing</em> cosmic scale parameter, “<em>a</em>”, then we can predict a maximum Hubble volume, with minimum CMB temperature for the voids, before contraction begins, as well as a minimum volume, with maximum CMB temperature, when expansion starts. A specific heat engine model for the cosmos is also entertained for this model of a closed universe. 展开更多
关键词 Cosmic Curvature closed universe Cyclic universe Heat Engine Model for universe Big Bounce Susceptibility Model for universe Carnot Cycle Model for Cosmos Causal Isotropy in CMB Temperature
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Temporal No-Linearity: An Alternative to Dark Energy
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作者 Bartolomé Pons-Rullán 《Journal of Modern Physics》 2022年第4期323-335,共13页
Mathematical compatibilities and constraints of a hypothetical 5D space-time with time referenced by two coordinates (3-2) have been revisited in detail in several recent papers. It has been prescribed from the GR the... Mathematical compatibilities and constraints of a hypothetical 5D space-time with time referenced by two coordinates (3-2) have been revisited in detail in several recent papers. It has been prescribed from the GR the compatibility constraints of the FLRW metric in each temporal brane, to be restricted to Closed Universes, Smooth Initial Singularities, and “Open CTC”. In a first view, this leads to leaving these works considering mathematical games discarded by the Standard Candles data. However, if time would be referred by two coordinates, they would not be linearly related, and it will be mathematically stated that space-time may not be flat in any case because time-like branes geometry will never be. If so, the time scale “lived” over a two-time dimension geodesic necessarily is not constant over its linear projection on one of both coordinates. Consequently, the correlations between Redshift and Distance Modulus—Distance Ladder—may be corrected by a synchronization function (if a no-linear two-time geodesic trajectory over a “warped temporal geometry” is linearly divided into constant segments, then their projections are not linear in any case). We apply an example of time-trajectory over the time slices, matching the Standard Candle data for a Closed Universe dominated by matter (>90%) in a bulk 3-2 configuration, with open temporal branes and smooth singularity. If time can be referred by two coordinates, then there is no need of Darkness to explain astrophysical data and Universe can be closed. 展开更多
关键词 closed universe MULTIDIMENSIONALITY Time-Like Dimensions No-Linear Time Accelerated Expansion Smooth Big Bang
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