THE PUZZLE OF GRAVITATION

2006 ◽  
Vol 21 (31) ◽  
pp. 6315-6321 ◽  
Author(s):  
B. G. SIDHARTH
Keyword(s):  
Dark Energy ◽  
Pion Mass ◽  
Planck Scale ◽  
Hubble Constant ◽  
Residual Energy ◽  
Gravitational Energy ◽  
The Other ◽  
Quantum Vacuum ◽  
The One ◽  
The Universe

We consider a model in which the Universe has an underpinning of oscillators in the quantum vacuum (or dark energy) at the Planck scale and deduce a number of otherwise inexplicable large number relations which have been considered to be empirical accidents. The analysis shows that the gravitational energy is the residual energy of the Planck oscillators constituting the Universe at large on the one hand, and elementary particles on the other. This explains a mysterious puzzle first pointed out by Weinberg several years ago, in a formula relating the pion mass to the Hubble constant, a puzzle which has remained unexplained ever since.

scholarly journals Possible Modification of the Standard Cosmological Model to Resolve a Tension with Hubble Constant Values

2021 ◽  
Vol 66 (9) ◽  
pp. 739
Author(s):  
S.L. Parnovsky
Keyword(s):  
Dark Energy ◽  
Hubble Constant ◽  
Baryonic Matter ◽  
Astronomical Observations ◽  
Significant Challenge ◽  
Λcdm Model ◽  
Modern Cosmology ◽  
Standard Cosmological Model ◽  
The One ◽  
The Universe

The tensions concerning the values of Hubble constant obtained from the early and the late Universe data pose a significant challenge to modern cosmology. Possible modifications of the flat homogeneous isotropic cosmological ΛCDM model are considered, in which the Universe contains the dark energy, cold baryonic matter, and dark matter. They are based on general relativity and satisfy two requirements: (1) the value of the Hubble constant calculated from the value of the Hubble parameter at the recombination by formulas of the flat ΛCDM model, should be equal to 92% of the one based on low-redshift observations; (2) deviations from the ΛCDM model should not lead to effects that contradict astronomical observations and estimations obtained thereof. The analysis showed that there are few opportunities for the choice. Either we should consider DM with negative pressure −pdmc2 ≪ pdm < 0, which weakly affects the evolution of the Universe and the observed manifestations of DM, or we should admit the mechanism of generation of new matter, for example, by the dark energy decay.

scholarly journals The graviton Compton mass as dark energy

2021 ◽  
Vol 67 (4 Jul-Aug) ◽  
pp. 040703
Author(s):  
T. Matos ◽  
L. L. -Parrilla
Keyword(s):  
Dark Energy ◽  
Hubble Constant ◽  
Accelerated Expansion ◽  
Coincidence Problem ◽  
Natural Explanation ◽  
Observable Universe ◽  
Local Distance ◽  
Free Constant ◽  
The One ◽  
The Universe

One of the greatest challenges of science is to understand the current accelerated expansion of the Universe. In this work we show that by considering the quantum nature of the gravitational field, its wavelength can be associated to an effective Compton mass. We propose that this mass can be interpreted as dark energy, with a Compton wavelength given by the size of the observable Universe, implying that the dark energy varies depending on this size. If we do so, we find that: 1.- Even without any free constant for dark energy, the evolution of the Hubble parameter is exactly the same as for the LCDM model, so this model has the same predictions as LCDM. 2.- The density rate of the dark energy is ΩΛ = 0.69 which is a very similar value as the one found by the Planck satellite ΩΛ = 0.684. 3.- The dark energy has this value because it corresponds to the actual size of the radius of the Universe, thus the coincidence problem has a very natural explanation. 4.- It is possible to find also a natural explanation to why observations inferred from the local distance ladder find the value H0 = 73 km/s/Mpc for the Hubble constant, we show that if we take the variability of the dark energy into account they should measure H0 = 67.3 km/s/Mpc as well. 5.- In this model the inflationary period contains a natural successful graceful exit.

scholarly journals The graviton Compton mass as Dark Energy

2021 ◽  
Vol 67 (4 Jul-Aug) ◽  
Author(s):  
Tonatiuh Matos ◽  
L. Parrilla
Keyword(s):  
Dark Energy ◽  
Hubble Constant ◽  
Accelerated Expansion ◽  
Coincidence Problem ◽  
Natural Explanation ◽  
Observable Universe ◽  
Local Distance ◽  
Free Constant ◽  
The One ◽  
The Universe

One of the greatest challenges of science is to understand the current accelerated expansion of the Universe. In this work we show that by considering the quantum nature of the gravitational field, its wavelength can be associated to an effective Compton mass. We propose that this mass can be interpreted as dark energy, with a Compton wavelength given by the size of the observable Universe, implying that the dark energy varies depending on this size. If we do so, we find that: 1.- Even without any free constant for dark energy, the evolution of the Hubble parameter is exactly the same as for the LCDM model, so this model has the same predictions as LCDM. 2.- The density rate of the dark energy is ΩΛ = 0.69 which is a very similar value as the one found by the Planck satellite ΩΛ = 0.684. 3.- The dark energy has this value because it corresponds to the actual size of the radius of the Universe, thus the coincidence problem has a very natural explanation. 4.- It is possible to find also a natural explanation to why observations inferred from the local distance ladder find the value H0 = 73 km/s/Mpc for the Hubble constant, we show that if we take the variability of the dark energy into account they should measure H0 = 67.3 km/s/Mpc as well. 5.- In this model the inflationary period contains a natural successful graceful exit.

Signature change in p-adic and noncommutative FRW cosmology

2014 ◽  
Vol 29 (27) ◽  
pp. 1450155 ◽  
Author(s):  
Goran S. Djordjevic ◽  
Ljubisa Nesic ◽  
Darko Radovancevic
Keyword(s):  
Loop Quantum Gravity ◽  
Initial Conditions ◽  
Planck Scale ◽  
The Other ◽  
Frw Cosmology ◽  
Signature Change ◽  
Discrete Nature ◽  
Frw Metric ◽  
The Universe ◽  
Friedmann Robertson Walker

The significant matter for the construction of the so-called no-boundary proposal is the assumption of signature transition, which has been a way to deal with the problem of initial conditions of the universe. On the other hand, results of Loop Quantum Gravity indicate that the signature change is related to the discrete nature of space at the Planck scale. Motivated by possibility of non-Archimedean and/or noncommutative structure of space–time at the Planck scale, in this work we consider the classical, p-adic and (spatial) noncommutative form of a cosmological model with Friedmann–Robertson–Walker (FRW) metric coupled with a self-interacting scalar field.

scholarly journals Weak scale from Planck scale: Mass scale generation in a classically conformal two-scalar system

2020 ◽  
Vol 2020 (3) ◽  
Author(s):  
Junichi Haruna ◽  
Hikaru Kawai
Keyword(s):  
Scalar Field ◽  
Standard Model ◽  
Planck Scale ◽  
Vacuum Expectation ◽  
Vacuum Expectation Value ◽  
The Other ◽  
Expectation Value ◽  
Weak Scale ◽  
The Standard Model ◽  
The One

Abstract In the standard model, the weak scale is the only parameter with mass dimensions. This means that the standard model itself cannot explain the origin of the weak scale. On the other hand, from the results of recent accelerator experiments, except for some small corrections, the standard model has increased the possibility of being an effective theory up to the Planck scale. From these facts, it is naturally inferred that the weak scale is determined by some dynamics from the Planck scale. In order to answer this question, we rely on the multiple point criticality principle as a clue and consider the classically conformal $\mathbb{Z}_2\times \mathbb{Z}_2$ invariant two-scalar model as a minimal model in which the weak scale is generated dynamically from the Planck scale. This model contains only two real scalar fields and does not contain any fermions or gauge fields. In this model, due to a Coleman–Weinberg-like mechanism, the one-scalar field spontaneously breaks the $ \mathbb{Z}_2$ symmetry with a vacuum expectation value connected with the cutoff momentum. We investigate this using the one-loop effective potential, renormalization group and large-$N$ limit. We also investigate whether it is possible to reproduce the mass term and vacuum expectation value of the Higgs field by coupling this model with the standard model in the Higgs portal framework. In this case, the one-scalar field that does not break $\mathbb{Z}_2$ can be a candidate for dark matter and have a mass of about several TeV in appropriate parameters. On the other hand, the other scalar field breaks $\mathbb{Z}_2$ and has a mass of several tens of GeV. These results will be verifiable in near-future experiments.

Aristotle's Unmoved Movers

Traditio ◽  
1946 ◽  
Vol 4 ◽  
pp. 1-30 ◽  
Author(s):  
Philip Merlan
Keyword(s):  
Middle Ages ◽  
The Other ◽  
World Picture ◽  
The Earth ◽  
Concentric Spheres ◽  
The One ◽  
The Universe ◽  
The Middle Ages

According to Aristotle all heavenly movement is ultimately due to the activity of forty-seven (or fifty-five) ‘unmoved movers'. This doctrine is highly remarkable in itself and has exercised an enormous historical influence. It forms part of a world-picture the outlines of which are as follows. The universe consists of concentric spheres, revolving in circles. The outermost of these bears the fixed stars. The other either bear planets or, insofar as they do not, contribute indirectly to the movements of the latter. Each sphere is moved by the one immediately surrounding it, but also possesses a movement of its own, due to its mover, an unmoved, incorporeal being. (It was these beings which the schoolmen designated as theintelligentiae separatae.) The seemingly irregular movements of the planets are thus viewed as resulting from the combination of regular circular revolutions. The earth does not move and occupies the centre of the universe. Such was Aristotle's astronomic system, essential parts of which were almost universally adopted by the Arabic, Jewish, and Christian philosophers of the Middle Ages.

BLACK HOLE - DESTROYER

2021 ◽  
Author(s):  
Иштимер Шагалиевич Хурамшин
Keyword(s):  
Black Hole ◽  
The Other ◽  
Baryonic Matter ◽  
Evolution Of The Universe ◽  
The Galaxy ◽  
The One ◽  
The Universe

В статье обсуждается вопрос о двух противоположных функциях черной дыры. С одной стороны она является творцом для галактики, а с другой - разрушителем барионной материи. Предполагается, что эти функции заложены самой эволюцией Вселенной. Деструкция материи до фотонов в ЧД считается наиболее вероятным событием. The question of two opposite functions of a black hole is discussed. On the one hand, it is the creator for the galaxy, and on the other-the destroyer of baryonic matter. It is assumed that these functions were laid down by the evolution of the Universe itself. The destruction of matter to photons in BH is considered the most likely event.

scholarly journals The dark sector cosmology

2020 ◽  
Vol 29 (14) ◽  
pp. 2030014
Author(s):  
Elcio Abdalla ◽  
Alessandro Marins
Keyword(s):  
Dark Energy ◽  
Cosmological Parameters ◽  
Hubble Constant ◽  
Acoustic Oscillations ◽  
Dark Sector ◽  
Fundamental Physics ◽  
Observational Techniques ◽  
Distance Indicators ◽  
The Universe ◽  
Theoretical Developments

The most important problem in fundamental physics is the description of the contents of the Universe. Today, we know that 95% thereof is totally unknown. Two thirds of that amount is the mysterious Dark Energy described in an interesting and important review [E. J. Copeland, M. Sami and S. Tsujikawa, Int. J. Mod. Phys. D 15 (2006) 1753]. We briefly extend here the ideas contained in that review including the more general Dark Sector, that is, Dark Matter and Dark Energy, eventually composing a new physical Sector. Understanding the Dark Sector with precision is paramount for us to be able to understand all the other cosmological parameters comprehensively as modifications of the modeling could lead to potential biases of inferred parameters of the model, such as measurements of the Hubble constant and distance indicators such as the Baryon Acoustic Oscillations. We discuss several modern methods of observation that can disentangle the different possible descriptions of the Dark Sector. The possible applications of some theoretical developments are also included in this paper as well as a more thorough evaluation of new observational techniques at lower frequencies and gravitational waves.

DIRAC'S COSMOLOGY AND RADIOACTIVE DATING

1963 ◽  
Vol 41 (11) ◽  
pp. 1911-1923 ◽  
Author(s):  
E. R. Kanasewich ◽  
J. C. Savage
Keyword(s):  
Decay Rate ◽  
Decay Constant ◽  
The Other ◽  
Large Uncertainty ◽  
Β Decay ◽  
Α Decay ◽  
Age Of The Universe ◽  
The One ◽  
The Universe

It has long been recognized that Dirac's principle might imply that the rate of β decay would vary with the age of the universe. If so, the radioactive ages of meteorites and terrestrial rocks as indicated on the one hand by α decay and on the other by β decay should differ. However, the comparison of these ages is complicated by a large uncertainty in the decay constant for Rb87. Thus the age data must be analyzed to determine the decay constant most compatible with the particular theory of β decay which is used. Using this best decay constant for each theory, we find that the data are more consistent with a β decay rate independent of the age of the universe than with the dependence implied by the Dirac principle.

scholarly journals Manifestations of dark energy in the dynamics of the Solar system

2009 ◽  
Vol 5 (S264) ◽  
pp. 410-412
Author(s):  
Michal Křížek ◽  
Jan Brandts
Keyword(s):  
Dark Energy ◽  
Solar System ◽  
Hubble Constant ◽  
The Sun ◽  
Expansion Speed ◽  
Current Value ◽  
The Impact ◽  
The Universe

AbstractThe expansion speed of the Universe is increasing (Glanz 1998). This acceleration is attributed to dark energy which acts almost uniformly everywhere (including the Solar system) and thus essentially influences the Hubble constant. Its current value on a distance of 1 AU is H0 = 10 m/(yr AU). This is quite a large number and thus, the impact of dark energy should be detectable in the Solar system. We will illustrate it by several examples. Dark energy may partially be caused by gravitational aberration of the Sun, planets and other bodies.

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