Searcharxiv⌕ Search

arXiv subjects

T. R. Mongan

Publications and source records attributed to T. R. Mongan.

14 recordsLinked to original sources
arXiv2017

MOND is unnecessary

Dark matter seems to account for flat velocity curves in spiral galaxies, with further evidence for dark matter from observations of the colliding "bullet cluster" galaxies 1E0657-56. However, the baryonic Tully-Fisher relation and the mass discrepancy-acceleration relation have been cited (arXiv:1112.3960) as "challenges for the LambdaCDM model." MOND (MOdified Newtonian Dynamics), a modified law of gravity,is invoked in arXiv:1112.3960 to account for those relations. This note shows that the HLSS model in arXiv:1301.0304, employing the holographic principle within the standard LambdaCDM paradigm, readily accounts for the MOND acceleration, the baryonic Tully-Fisher relation, and the mass discrepancy-acceleration relation. After first posting this note, I learned that Man Ho Chan (arXiv:1310.6801) previously reached the same conclusion using a dark matter based analysis independent of the holographic approach used in this paper. These results indicate that the MOND hypothesis is unnecessary.

physics.gen-ph↗
arXiv2015

Holography, large scale structure, supermassive black holes, and minimum stellar mass

This analysis considers our universe as a closed Friedmann universe, dominated by vacuum energy in the form of a cosmological constant, with cosmological parameters obtained from full mission Planck satellite observations. A few simple assumptions lead to straightforward calculation of general features of large scale structures in the universe and minimum stellar mass as a function of redshift. Those assumptions also generate upper and lower bounds on supermassive black hole mass in relation to total stellar mass of the host galaxy, consistent with observations across four orders of magnitude of black hole mass and five orders of magnitude of galactic stellar mass. The results are based only on fundamental constants and measured cosmological parameters. No arbitrary parameters are involved.

physics.gen-ph↗
arXiv2013

A holographic charged preon model

The Standard Model (SM) is a successful approach to particle physics calculations. However, there are indications that the SM is only a good approximation to an underlying non-local reality involving fundamental entities (preons) that are not point particles. Furthermore, our universe seems to be dominated by a vacuum energy/cosmological constant. The holographic principle then indicates only a finite number of bits of information will ever be available to describe the observable universe, and that requires a holographic preon model linking the (0,1) holographic bits to SM particles. All SM particles have charges 0, 1/3, 2/3 or 1 in units of the electron charge, so the bits in a holographic preon model must be identified with fractional electric charge. Such holographic charged preon models require baryon asymmetry and also suggest a mechanism for stationary action. This paper outlines a holographic charged preon model where preons are strands with finite energy density specified by bits of information identifying the charge on each end. In the model, SM particles consist of three strands with spin states corresponding to wrapped states of the strands. SM particles in this wrapped preon model can be approximated by preon bound states in non-local dynamics based on three-preon Bethe-Salpeter equations with instantaneous three-preon interactions. The model can be falsified by data from the Large Hadron Collider because it generates baryon asymmetry without axions, and does not allow more than three generations of SM fermions.

physics.gen-ph↗
arXiv2012

Holography, charge and baryon asymmetry

The reason for baryon asymmetry in our universe has been a pertinent question for many years. The holographic principle suggests a charged preon model underlies the Standard Model of particle physics and any such charged preon model requires baryon asymmetry. This note estimates the baryon asymmetry predicted by charged preon models in closed inflationary Friedmann universes.

physics.gen-ph↗
arXiv2011

Dark matter from "strong gravity" - consistent with CRESST, CoGeNT and DAMA/LIBRA

Kelso, Hooper and Buckley [arXiv:1110.5338] found CRESST, CoGeNT and DAMA/LIBRA results are consistent with 10 - 15 GeV dark matter particles. Hennawi and Ostriker [arXiv:astro-ph/0108203] analyzed supermassive black hole formation in the centers of galaxies, finding a best fit for dark matter (self-interaction cross-section)/mass ratio = 0.02 cm^{2}/g, with round-off error of 25%. Combining the Hennawi/Ostriker result with the "strong gravity" model for dark matter [arXiv:0706.3050] requires dark matter particles with mass between 10.5 GeV and 17.5 GeV, overlapping the Kelso/Hooper/Buckley dark matter particle mass range.

gr-qc↗
arXiv2011

Holographic principle and large scale structure in the universe

A reasonable representation of large scale structure, in a closed universe so large it's nearly flat, can be developed by extending the holographic principle and assuming the bits of information describing the distribution of matter density in the universe remain in thermal equilibrium with the cosmic microwave background radiation. The analysis identifies three levels of self-similar large scale structure, corresponding to superclusters, galaxies, and star clusters, between today's observable universe and stellar systems. The self-similarity arises because, according to the virial theorem, the average gravitational potential energy per unit volume in each structural level is the same and depends only on the gravitational constant. The analysis indicates stellar systems first formed at z\approx62, consistent with the findings of Naoz et al, and self-similar large scale structures began to appear at redshift z\approx4. It outlines general features of development of self-similar large scale structures at redshift z<4. The analysis is consistent with observations for angular momentum of large scale structures as a function of mass, and average speed of substructures within large scale structures. The analysis also indicates relaxation times for star clusters are generally less than the age of the universe and relaxation times for more massive structures are greater than the age of the universe.

physics.gen-ph↗
arXiv2006

Holography and non-locality in a closed vacuum-dominated universe

A closed vacuum-dominated Friedmann universe is asymptotic to a de Sitter space with a cosmological event horizon for any observer. The holographic principle says the area of the horizon in Planck units determines the number of bits of information about the universe that will ever be available to any observer. The wavefunction describing the probability distribution of mass quanta associated with bits of information on the horizon is the boundary condition for the wavefunction specifying the probability distribution of mass quanta throughout the universe. Local interactions between mass quanta in the universe cause quantum transitions in the wavefunction specifying the distribution of mass throughout the universe, with instantaneous non-local effects throughout the universe.

gr-qc↗
arXiv2006

Hierarchy and Wave Functions in a Simple Quantum Cosmology

Astrophysical observations indicate the expansion of the universe is accelerating. Applying the holographic entropy conjecture to the cosmological horizon in an accelerating universe suggests the universe has only a finite number of degrees of freedom. This is consistent with a closed universe arising from a quantum fluctuation, with zero total quantum numbers. If space-time has eleven dimensions, and the universe began as a closed force-symmetric ten-dimensional space with characteristic dimension L, seven of the space dimensions must have collapsed to generate the three large space dimensions we see. The holographic conjecture then suggests the initial length scale L must be roughly twenty orders of magnitude larger than the Planck length. Accordingly, the nuclear force must be roughly forty orders of magnitude stronger than gravity, possibly resolving the force hierarchy problem. A wavefunction for the radius of curvature of the universe can be obtained from the Schrodinger equation derived by Elbaz and Novello. The product of this wavefunction and its complex conjugate can be interpreted as the probability density for finding a given radius of curvature in one of the infinity of measurements of the radius of curvature possible (in principle) at any location in a homogeneous isotropic universe.

hep-ph↗
arXiv2005

Simple quantum cosmology: Vacuum energy and initial state

A static non-singular 10-dimensional closed Friedmann universe of Planck size, filled with a perfect fluid with an equation of state with w = -2/3, can arise spontaneously by a quantum fluctuation from nothing in 11-dimensional spacetime. A quantum transition from this state can initiate the inflationary quantum cosmology outlined in Ref. 2 [General Relativity and Gravitation 33, 1415, 2001 - gr-qc/0103021]. With no fine-tuning, that cosmology predicts about 60 e-folds of inflation and a vacuum energy density depending only on the number of extra space dimensions (seven), G, h, c and the ratio between the strength of gravity and the strength of the strong force. The fraction of the total energy in the universe represented by this vacuum energy depends on the Hubble constant. Hubble constant estimates from WMAP, SDSS, the Hubble Key Project and Sunyaev-Zeldovich and X-ray flux measurements range from 60 to 72 km/(Mpc sec). With a mid-range Hubble constant of 65 km/(Mpc sec), the model in Ref. 2 predicts Omega-sub-Lambda = 0.7

gr-qc↗
arXiv2003

Vacuum dominance and holography

A cosmological event horizon develops in a vacuum-dominated Friedmann universe. The Schwarschild radius of the vacuum energy within the horizon equals the horizon radius. Black hole thermodynamics and the holographic conjecture indicate a finite number of degrees of freedom within the horizon. The average energy per degree of freedom equals the energy of a massless quantum with wavelength of the horizon circumference. This suggests identifying the degrees of freedom with the presence or absence, in each Planck area on one horizon quadrant, of a 0S2 vibrational mode of the horizon with the z axis passing through that area. Pressure waves on the horizon (the superposition of 0S2 vibrational modes) can be envisioned to propagate into the observable universe within the horizon at the speed of light. So, the vacuum energy and pressure throughout the observable universe could (in principle) be determined from the vacuum equation of state.

gr-qc↗
arXiv2001

A simple quantum cosmology

A simple and surprisingly realistic model of the origin of the universe can be developed using the Friedmann equation from general relativity, elementary quantum mechanics, and the experimental values of h, c, G and the proton mass. The model assumes there are N space dimensions (with N > 6) and the potential constraining the radius r of the invisible N -3 compact dimensions varies as r^4. In this model, the universe has zero total energy and is created from nothing. There is no initial singularity. If space-time is eleven dimensional, as required by M theory, the scalar field corresponding to the size of the compact dimensions inflates the universe by about 26 orders of magnitude (60 e-folds). If the Hubble constant is 65 km/sec Mpc, the energy density of the scalar field after inflation results in Omega-sub-Lambda = 0.68, in agreement with recent astrophysical observations.

gr-qc↗
arXiv1999

Quantum mechanics forbids an initial or final singularity in a closed FRW universe

The existence of singularities in a closed FRW universe depends on the assumption that general relativity is valid for distances less than the Planck length. However, stationary state wave functions of the Schrodinger equation for a closed radiation-dominated FRW universe derived by Elbaz et al (General Relativity and Gravitation 29, 481, 1997) are zero at zero radius of curvature. Thus, even if general relativity is assumed valid at distances less than the Planck length, quantum mechanics seems to forbid singularities in a closed FRW universe.

gr-qc↗
arXiv1999

N + 1 dimensional quantum mechanical model for a closed universe

A quantum mechanical model for an N + 1 dimensional universe arising from a quantum fluctuation is outlined. (3 + 1) dimensions are a closed infinitely-expanding universe and the remaining N - 3 dimensions are compact. The (3 + 1) non-compact dimensions are modeled by quantizing a canonical Hamiltonian description of a homogeneous isotropic universe. It is assumed gravity and the strong-electro-weak (SEW) forces had equal strength in the initial state. Inflation occurred when the compact N -3 dimensional space collapsed after a quantum transition from the initial state of the univers, during its evolution to the present state where gravity is much weaker than the SEW force. The model suggests the universe has no singularities and the large size of our present universe is determined by the relative strength of gravity and the SEW force today. A small cosmological constant, resulting from the zero point energy of the scalar field corresponding to the compact dimensions, makes the model universe expand forever.

gr-qc↗