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1 pages, 185 KiB

Open AccessEditorial

Statement of Peer Review

by Lorenzo Iorio

Phys. Sci. Forum 2023, 7(1), 57; https://doi.org/10.3390/psf2023007057 - 17 May 2023

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Abstract

In submitting conference proceedings to Physical Sciences Forum, the volume editors of the proceedings certify to the publisher that all papers published in this volume have been subjected to peer review administered by the volume editors [...] Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

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Jump to: Editorial

5 pages, 231 KiB

Open AccessProceeding Paper

Majorana Mass Term of Majorana Spinors

by Vadim Monakhov

Phys. Sci. Forum 2023, 7(1), 1; https://doi.org/10.3390/ECU2023-14016 - 15 Feb 2023

Viewed by 1713

Abstract

We have proven that, under the standard charge conjugation approach, the Majorana mass term in QFT must vanish. We have derived formulas for the Majorana spinor field operator without any assumptions about the second quantization procedure. The fact that the Majorana mass term [...] Read more.

We have proven that, under the standard charge conjugation approach, the Majorana mass term in QFT must vanish. We have derived formulas for the Majorana spinor field operator without any assumptions about the second quantization procedure. The fact that the Majorana mass term vanishes not only in the c-theory, which was known, but also in the q-theory (the theory of second quantization), requires a revision of ideas about the generation of neutrino mass using the seesaw mechanism. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

4 pages, 250 KiB

Open AccessProceeding Paper

String-Inspired Correction to R² Inflation

by Ekaterina Pozdeeva, Sergei Ketov and Sergey Vernov

Phys. Sci. Forum 2023, 7(1), 2; https://doi.org/10.3390/ECU2023-14036 - 16 Feb 2023

Viewed by 921

Abstract

We study the Starobinsky–Bel–Robinson inflationary model in the slow-roll regime. In the framework of higher-curvature corrections to inflationary parameters, we estimate the maximal possible value of the dimensionless positive coupling constant

β

coming from M-theory. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

6 pages, 990 KiB

Open AccessProceeding Paper

Imprint of the Crystallization of Binary White Dwarfs on Gravitational Wave Observations with LISA

by Loïc Perot and Nicolas Chamel

Phys. Sci. Forum 2023, 7(1), 3; https://doi.org/10.3390/ECU2023-14023 - 15 Feb 2023

Viewed by 1131

Abstract

Space-based gravitational-wave detectors, such as the Laser Interferometer Space Antenna, allow for the probing of the interior of white dwarfs in binaries through the imprints of tidal effects on the gravitational wave signal. In this study, we have computed the tidal deformability of [...] Read more.

Space-based gravitational-wave detectors, such as the Laser Interferometer Space Antenna, allow for the probing of the interior of white dwarfs in binaries through the imprints of tidal effects on the gravitational wave signal. In this study, we have computed the tidal deformability of white dwarfs in full general relativity, taking into account the crystallization of their core. The elasticity of the core is found to systematically reduce the tidal deformability, especially for low-mass stars. Moreover, it is shown that errors on the tidal deformability due to the use of the Newtonian theory can become important for massive white dwarfs. Finally, the orbital evolution of eccentric binaries is investigated. Measuring the precession rate of these systems could provide estimations of the individual masses. However, it is found that the neglect of crystallization could lead to very large errors. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

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7 pages, 657 KiB

Open AccessProceeding Paper

Entanglement—A Higher Order Symmetry

by Paul O’Hara

Phys. Sci. Forum 2023, 7(1), 4; https://doi.org/10.3390/ECU2023-14011 - 15 Feb 2023

Cited by 1 | Viewed by 1334

Abstract

Can we accurately model the spin state of a quantum particle? If so, we should be able to make identical copies of such a state and also obtain its mirror image. In quantum mechanics, many subatomic particles can form entangled pairs that are [...] Read more.

Can we accurately model the spin state of a quantum particle? If so, we should be able to make identical copies of such a state and also obtain its mirror image. In quantum mechanics, many subatomic particles can form entangled pairs that are mirror images of each other, although the state of an individual particle cannot be duplicated or cloned as experimentally demonstrated by Aspect, Clauser and Zeilinger, the winners of the Nobel Prize in Physics 2022. We show that there is a higher-order symmetry associated with the SL(2,C) group that underlies the singlet state, which means that the singlet pairing preserves Lorentz transformations independently of the metric used. The Pauli exclusion principle can be derived from this symmetry. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

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5 pages, 251 KiB

Open AccessProceeding Paper

Testing Quantum Effects of Gravity and Dark Energy at Laboratory Scales

by Kenath Arun, Chandra Sivaram and Avijeet Prasad

Phys. Sci. Forum 2023, 7(1), 5; https://doi.org/10.3390/ECU2023-14018 - 15 Feb 2023

Viewed by 1018

Abstract

One of the biggest challenges in modern physics is how to unify gravity with quantum theory. There is an absence of a complete quantum theory of gravity, and conventionally it is thought that the effects of quantum gravity occur only at high energies [...] Read more.

One of the biggest challenges in modern physics is how to unify gravity with quantum theory. There is an absence of a complete quantum theory of gravity, and conventionally it is thought that the effects of quantum gravity occur only at high energies (Planck scale). Here, we suggest that certain novel quantum effects of gravity can become significant even at lower energies and could be tested at laboratory scales. We also suggest a few indirect effects of dark energy that can show up at laboratory scales. Using these ideas, we set observational constraints on radio recombination lines of the Rydberg atoms. We further suggest that high-precision measurements of Casimir effects for smaller plate separation could also show some manifestations of the presence of dark energy. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

6 pages, 294 KiB

Open AccessProceeding Paper

On Extensions of the Starobinsky Model of Inflation

by Vsevolod Ivanov, Sergei Ketov, Ekaterina Pozdeeva and Sergey Vernov

Phys. Sci. Forum 2023, 7(1), 6; https://doi.org/10.3390/ECU2023-14044 - 16 Feb 2023

Cited by 1 | Viewed by 1195

Abstract

We propose inflationary models that are one-parametric generalizations of the Starobinsky

R + R^{2}

model. Using the conformal transformation, we obtain scalar field potentials in the Einstein frame that are one-parametric generalizations of the potential for the Starobinsky inflationary model. We restrict [...] Read more.

We propose inflationary models that are one-parametric generalizations of the Starobinsky

R + R^{2}

model. Using the conformal transformation, we obtain scalar field potentials in the Einstein frame that are one-parametric generalizations of the potential for the Starobinsky inflationary model. We restrict the form of the potentials by demanding that the corresponding function

F (R)

is an elementary function. We obtain the inflationary parameters of the models proposed and show that the predictions of these models agree with current observational data. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

7 pages, 2837 KiB

Open AccessProceeding Paper

Results and Prospects of the Hellenic Open University Air Shower Array

by Stavros Nonis, Antonios Leisos and Apostolos Tsirigotis

Phys. Sci. Forum 2023, 7(1), 7; https://doi.org/10.3390/ECU2023-14015 - 15 Feb 2023

Viewed by 1061

Abstract

Astroneu is an array of autonomous extensive air shower detection stations deployed at the Hellenic Open University (HOU) campus on the outskirts of Patras in Western Greece. In the first phase of operation, nine scintillators detectors and three radio frequency (RF) antennas have [...] Read more.

Astroneu is an array of autonomous extensive air shower detection stations deployed at the Hellenic Open University (HOU) campus on the outskirts of Patras in Western Greece. In the first phase of operation, nine scintillators detectors and three radio frequency (RF) antennas have been installed and operated at the site. The detector units were arranged in three autonomous stations each consisting of three scintillator detectors (SDM) and one RF antenna. In the second phase of operation, three more antennas were deployed at one station in order to study the correlation of the RF signals from four antennas subject to the same shower event. In this report, we present the standard offline SDM-RF data and simulations analysis, the main research results concerning the reconstruction of the EAS parameters as well as the prospects of a new compact array that will be deployed by 2023. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

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4 pages, 764 KiB

Open AccessProceeding Paper

Dark Matter in the Milky Way as the F-Type of Vacuum Polarization

by Sergey L. Cherkas and Vladimir L. Kalashnikov

Phys. Sci. Forum 2023, 7(1), 8; https://doi.org/10.3390/ECU2023-14025 - 15 Feb 2023

Viewed by 900

Abstract

Dark matter in the Milky Way is explained by the F-type of vacuum polarization, which could represent dark radiation. A nonsingular solution for dark radiation exists in the presence of eicheon (i.e., black hole in old terminology) in the galaxy’s center. The model [...] Read more.

Dark matter in the Milky Way is explained by the F-type of vacuum polarization, which could represent dark radiation. A nonsingular solution for dark radiation exists in the presence of eicheon (i.e., black hole in old terminology) in the galaxy’s center. The model is spherically symmetric, but an approximate surface density of a baryonic galaxy disk is taken into account by smearing the disk over a sphere. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

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5 pages, 938 KiB

Open AccessProceeding Paper

Gapless Superfluidity and Neutron Star Cooling

by Valentin Allard and Nicolas Chamel

Phys. Sci. Forum 2023, 7(1), 9; https://doi.org/10.3390/ECU2023-14022 - 15 Feb 2023

Viewed by 1276

Abstract

The presence of currents in the interior of cold neutron stars can lead to a state in which nucleons remain superfluid while the quasiparticle energy spectrum has no gap. We show within the self-consistent time-dependent nuclear energy density functional theory that the nucleon [...] Read more.

The presence of currents in the interior of cold neutron stars can lead to a state in which nucleons remain superfluid while the quasiparticle energy spectrum has no gap. We show within the self-consistent time-dependent nuclear energy density functional theory that the nucleon specific heat is then comparable to that in the normal phase, contrasting with the classical BCS result in the absence of super flows. This dynamical, gapless superfluid state has important implications for the cooling of neutron stars. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

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5 pages, 711 KiB

Open AccessProceeding Paper

Nuclear Pasta in Cold Non-Accreting Neutron Stars: Symmetry Energy Effects

by Nikolai N. Shchechilin, John M. Pearson and Nicolas Chamel

Phys. Sci. Forum 2023, 7(1), 10; https://doi.org/10.3390/ECU2023-14017 - 15 Feb 2023

Cited by 1 | Viewed by 1070

Abstract

The densest part of neutron star crusts may contain very exotic nuclear configurations, so-called nuclear pasta. We investigate the effect of nuclear symmetry energy on the existence of such phases in cold non-accreting neutron stars. For this purpose, we apply three Brussels–Montreal functionals [...] Read more.

The densest part of neutron star crusts may contain very exotic nuclear configurations, so-called nuclear pasta. We investigate the effect of nuclear symmetry energy on the existence of such phases in cold non-accreting neutron stars. For this purpose, we apply three Brussels–Montreal functionals based on generalized Skyrme effective interactions, whose parameters were accurately calibrated to reproduce both experimental data on nuclei and realistic neutron-matter equations of state. These functionals differ in their predictions for the density dependence of the symmetry energy. Within the fourth-order extended Thomas–Fermi method, we find that pasta occupies a wider region of the crust for models with a lower slope of the symmetry energy (and higher symmetry energy at relevant densities) in agreement with previous studies based on pure Thomas–Fermi approximation and compressible liquid-drop models. However, the incorporation of microscopic corrections consistently calculated with the Strutinsky integral method leads to a significant shift of the onset of the pasta phases to higher densities due to the enhanced stability of spherical clusters. As a result, the pasta region shrinks substantially and the role of symmetry energy weakens. This study sheds light on the importance of quantum effects for reliably describing pasta phases in neutron stars. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

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7 pages, 266 KiB

Open AccessProceeding Paper

Baryonic Matter Abundance in the Framework of MONG

by Louise Rebecca, Arun Kenath and Chandra Sivaram

Phys. Sci. Forum 2023, 7(1), 11; https://doi.org/10.3390/ECU2023-14021 - 15 Feb 2023

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Abstract

It is well established from various pieces of observational evidence that the relative abundance of baryonic matter in the Universe is less than 5%. The remaining 95% is made up of dark matter (DM) and dark energy. In view of the negative results [...] Read more.

It is well established from various pieces of observational evidence that the relative abundance of baryonic matter in the Universe is less than 5%. The remaining 95% is made up of dark matter (DM) and dark energy. In view of the negative results from dark matter detection experiments running for several years, we had earlier proposed alternate models (which do not require DM) by postulating a minimal field strength (analogous to minimal curvature) and a minimal acceleration. These postulates led to the Modification of Newtonian Dynamics (MOND) and Modification of Newtonian Gravity (MONG), respectively. Some of the independent results that support the existence of non-baryonic matter are the mass–radius relation (that holds true for any gravitationally bound large-scale structure), Eddington luminosity, etc. Here, we discuss how these physical implications can be accounted for from the results of MONG without invoking DM. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

6 pages, 280 KiB

Open AccessProceeding Paper

LRS Bianchi I Cosmological Model with Strange Quark Matter in f(R, T) Gravity

by Siwaphiwe Jokweni, Vijay Singh and Aroonkumar Beesham

Phys. Sci. Forum 2023, 7(1), 12; https://doi.org/10.3390/ECU2023-14037 - 16 Feb 2023

Cited by 3 | Viewed by 985

Abstract

A locally rotationally symmetric Bianchi-I model filled with strange quark matter is explored in

f (R, T) = R + 2 f (T)

gravity, where R is the Ricci scalar, T is the trace of the energy-momentum tensor [...] Read more.

A locally rotationally symmetric Bianchi-I model filled with strange quark matter is explored in

f (R, T) = R + 2 f (T)

gravity, where R is the Ricci scalar, T is the trace of the energy-momentum tensor and

λ

is an arbitrary constant. Exact solutions are obtained by assuming that the expansion scalar is proportional to the shear scalar. The model is found to be physically viable for

λ < - \frac{1}{4}

. Strange quark matter at early times mimics ultra-relativistic radiation whereas at late times it behaves as dust, quintessence, or even the cosmological constant for some specified values of

λ

. The effective matter acts as stiff matter irrespective of the matter content and of

f (R, T)

gravity. The model is shear-free at late times but remains anisotropic throughout the evolution. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

6 pages, 330 KiB

Open AccessProceeding Paper

f(R,T) Gravity and Constant Jerk Parameter in FLRW Spacetime †

by Değer Sofuoğlu and Aroonkumar Beesham

Phys. Sci. Forum 2023, 7(1), 13; https://doi.org/10.3390/ECU2023-14038 - 16 Feb 2023

Viewed by 1326

Abstract

It is well known that the universe is undergoing accelerated expansion during recent times and that it underwent a decelerated expansion in early times. The deceleration parameter, essentially the second derivative of the scale factor, can be used to describe these eras, with [...] Read more.

It is well known that the universe is undergoing accelerated expansion during recent times and that it underwent a decelerated expansion in early times. The deceleration parameter, essentially the second derivative of the scale factor, can be used to describe these eras, with a negative parameter for acceleration and a positive parameter for deceleration. Apart from the standard

Λ

CDM model in general relativity, there are many cosmological models in various other theories of gravity. In order to describe these models, especially the deviation from general relativity, the jerk parameter was introduced, which is basically the third derivative of the scale factor. In the

Λ

CDM model in general relativity, the jerk parameter j is constant, and

j = 1

. The constant jerk parameter,

j = 1

, leads to two different scale factor solutions, one power law and the other exponential. The power-law solution corresponds to a model in which our universe expands with deceleration, while the exponential solution corresponds to a model in which it expands by accelerating. In this study, the cosmological consequences of such a selection of the jerk parameter on the non-minimally coupled

f (R, T)

theory of gravity (where R is the Ricci scalar, and T is the trace of the energy–momentum tensor) and the dynamic properties of these models are investigated on a flat Friedmann–Lemaitre–Robertson–Walker backgfround. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

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7 pages, 3497 KiB

Open AccessProceeding Paper

Introduction to a “Radical” Working Hypothesis about a Hemisphere-Scale Impact on Dione (Saturn)

by Balázs Bradák, Mayuko Nishikawa and Christopher Gomez

Phys. Sci. Forum 2023, 7(1), 14; https://doi.org/10.3390/ECU2023-14010 - 15 Feb 2023

Viewed by 798

Abstract

The study introduces a theory about a giant impact on the surface of Dione. Our study suspects a relatively low-velocity (≤5 km/s) collision between a c.a. 50–80 km diameter object and Dione, which might have resulted in the resurfacing of its intermediate cratered [...] Read more.

The study introduces a theory about a giant impact on the surface of Dione. Our study suspects a relatively low-velocity (≤5 km/s) collision between a c.a. 50–80 km diameter object and Dione, which might have resulted in the resurfacing of its intermediate cratered terrain. The source of the impactor might have been a unique satellite-centric debris, a unique impactor population, suspected in the Saturnian system. Other possible candidates are asteroid(s) appearing during the outer Solar System heavy bombardment period, or a collision, which might have happened during the “giant impact phase” in the early Saturnian system (coinciding with the Late Heavy Bombardment, or not). Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

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6 pages, 1462 KiB

Open AccessProceeding Paper

Mergers and Tidal Breakups of Binary Systems of Primordial DM Planets with Baryon Admixture and Emission of Gravitational Waves

by OV Kiren, Kenath Arun, Chandra Sivaram and KT Paul

Phys. Sci. Forum 2023, 7(1), 15; https://doi.org/10.3390/ECU2023-14028 - 15 Feb 2023

Viewed by 865

Abstract

Here, we discuss the possibility of the admixture of baryons to the DM primordial planets, with the DM particles varying in mass from 20 GeV to 100 GeV. We have considered different fractions of admixture particles to form the planet. The mass of [...] Read more.

Here, we discuss the possibility of the admixture of baryons to the DM primordial planets, with the DM particles varying in mass from 20 GeV to 100 GeV. We have considered different fractions of admixture particles to form the planet. The mass of the primordial planet made completely of DM ranges from asteroid mass to Neptune mass. However, the mass of primordial planets (admixed with DM and baryonic matter) is found to increase with the fraction of baryonic matter in the planets, and the mass of these objects can go well beyond the mass of Jupiter (around 40 times Jupiter’s mass) and can also approach sub-stellar mass (brown dwarf mass). So far, thousands of exoplanets have been discovered by the Kepler mission and more will be found by NASA’s Transiting Exoplanet Survey Satellite (TESS) mission, which is observing the entire sky to locate planets orbiting the nearest and brightest stars. Many exoplanets, such as exo-Jupiter, discovered so far fall in this mass range, and unsure whether these exoplanets are entirely made of baryons. Some of the exoplanets with a mass several times Jupiter’s mass could be possible signatures of the presence of primordial planets with an admixture of baryonic and DM particles. It is also found that some of these planets could reach even sub-stellar mass (10³² g), such as that of a brown dwarf. Additionally, even if a small fraction of DM particles is trapped in these objects, the flux of ambient DM particles would be reduced significantly. This could be one of the many reasons for not detecting the DM particles in various experiments, such as XENON1T, etc., as suggested earlier. If two such primordial planets (in a binary system) merge, they will release a lot of energy. The energy released in gravitational waves, as well as the time scale of the merger of these objects, is found to increase with the mass of primordial objects. The frequency of gravitational waves emitted in these systems is matching within the range of LIGO. The objects near the galactic center could consist of such primordial objects, planets, comets, etc. We also discuss the possibility of the tidal break up of these primordial objects in the presence of a BH. The mass of BH required for tidal break up is calculated, and it is found that the mass of BH required for tidal break up increases with the DM particle mass and also with the increase in the fraction of baryons in these objects. The energy released during tidal breakup will be emitted as gravitational waves. The energy released, as well as the frequency of waves, is tabulated, and the frequency is in the sensitivity range of LIGO. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

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4 pages, 683 KiB

Open AccessProceeding Paper

Thermodynamic Investigation of the QCD Phase Diagram with 2+1 Quark Flavors

by Hayet Sahi and Amal Ait El Djoudi

Phys. Sci. Forum 2023, 7(1), 16; https://doi.org/10.3390/ECU2023-14024 - 15 Feb 2023

Viewed by 1020

Abstract

This work deals with the deconfinement phase transition from a hadronic gas (HG) phase consisting of massive pions, to a quark–gluon plasma (QGP) phase consisting of gluons, massless up and down quarks and massive strange quarks, in addition to their antiquarks. Based on [...] Read more.

This work deals with the deconfinement phase transition from a hadronic gas (HG) phase consisting of massive pions, to a quark–gluon plasma (QGP) phase consisting of gluons, massless up and down quarks and massive strange quarks, in addition to their antiquarks. Based on the Bag and coexistence models, we study the variations of pressure characterizing both HG and QGP phases. For the latter, we calculate the partition function of the color-singlet QGP within the projection method using a density of states containing the volume term only. We investigate the phase diagram of the strongly interacting matter, in the µ–T plane, in several cases: in the HG phase, we consider massless pions then we account for their masses, and in the QGP phase, first we take it consisting of two massless u and d quarks, then we consider additional massive strange quarks. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

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6 pages, 281 KiB

Open AccessProceeding Paper

Cosmological Solutions of Integrable F(R) Gravity Models with an Additional Scalar Field

by Sergey Vernov and Vsevolod Ivanov

Phys. Sci. Forum 2023, 7(1), 17; https://doi.org/10.3390/ECU2023-14039 - 16 Feb 2023

Viewed by 872

Abstract

We consider

F (R)

cosmological models with a scalar field. For the

R^{2}

model in the spatially flat Friedmann–Lemaître–Robertson–Walker metric, the Ricci scalar R can smoothly change its sign during the evolution if and only if the scalar field is [...] Read more.

We consider

F (R)

cosmological models with a scalar field. For the

R^{2}

model in the spatially flat Friedmann–Lemaître–Robertson–Walker metric, the Ricci scalar R can smoothly change its sign during the evolution if and only if the scalar field is a phantom one. In the Bianchi I metric, the Ricci scalar cannot smoothly change its sign if the corresponding solution is anisotropic at

R = 0

. This result does not depend on the type of the scalar field. In the Bianchi I metric, the general solution of evolution equations has been obtained. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

7 pages, 4719 KiB

Open AccessProceeding Paper

Stacking Lake Ice Analog Cryotectonic Dynamics on Dione’s Wispy Terrain

by Balázs Bradák, Roland Novák and Christopher Gomez

Phys. Sci. Forum 2023, 7(1), 18; https://doi.org/10.3390/ECU2023-14030 - 15 Feb 2023

Viewed by 968

Abstract

Wispy Terrain, with its chasmata, is one of the enigmatic regions of Dione. It consists of quasi-parallel graben, and troughs, in parts with horsts, indicating extensional and shear stresses. This study introduces some observations of compression-related features and proposes a new regional formation [...] Read more.

Wispy Terrain, with its chasmata, is one of the enigmatic regions of Dione. It consists of quasi-parallel graben, and troughs, in parts with horsts, indicating extensional and shear stresses. This study introduces some observations of compression-related features and proposes a new regional formation model. The study of the relationship between impact craters and tectonic features revealed certain “lost” parts of some crosscut craters, indicating additional cryotectonic features, the appearance of accretionary prism-like phenomena, and, theoretically, subsumption-like processes. This study provides new information about the surface renewal processes at one of the youngest and probably still active regions of Dione. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

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6 pages, 911 KiB

Open AccessProceeding Paper

Search for Exoplanets with a Possible Surface Water Ocean

by Roland Novak, Balazs Bradak, Jozsef Kovacs and Christopher Gomez

Phys. Sci. Forum 2023, 7(1), 19; https://doi.org/10.3390/ECU2023-14020 - 15 Feb 2023

Viewed by 963

Abstract

In this work, we examined characteristics of the currently confirmed exoplanet population in order to characterize some of the crucial parameters for ocean formation. Two correlation heatmaps were created: one for the exoplanets in general, and one for exoplanets that can be found [...] Read more.

In this work, we examined characteristics of the currently confirmed exoplanet population in order to characterize some of the crucial parameters for ocean formation. Two correlation heatmaps were created: one for the exoplanets in general, and one for exoplanets that can be found in the habitable zone according to calculations. Based on these, we found possible associations between planetary radius/mass, stellar metallicity, and multiple characteristics. We propose plans for further studies of possible proxies for exoplanetary ocean exploration. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

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7 pages, 291 KiB

Open AccessProceeding Paper

Forecasts for ΛCDM and Dark Energy Models through Einstein Telescope Standard Sirens

by Matteo Califano, Ivan de Martino, Daniele Vernieri and Salvatore Capozziello

Phys. Sci. Forum 2023, 7(1), 20; https://doi.org/10.3390/ECU2023-14032 - 16 Feb 2023

Cited by 1 | Viewed by 995

Abstract

Gravitational wave (GW) astronomy provides an independent way to estimate cosmological parameters. The detection of GWs from a coalescing binary allows a direct measurement of its luminosity distance, so these sources are referred to as “standard sirens” in analogy to standard candles. We [...] Read more.

Gravitational wave (GW) astronomy provides an independent way to estimate cosmological parameters. The detection of GWs from a coalescing binary allows a direct measurement of its luminosity distance, so these sources are referred to as “standard sirens” in analogy to standard candles. We investigate the impact of constraining cosmological models on the Einstein Telescope, a third-generation detector which will detect tens of thousands of binary neutron stars. We focus on non-flat ΛCDM cosmology and some dark energy models that may resolve the so-called Hubble tension. To evaluate the accuracy down to which ET will constrain cosmological parameters, we consider two types of mock datasets depending on whether or not a short gamma-ray burst is detected and associated with the gravitational wave event using the THESEUS satellite. Depending on the mock dataset, different statistical estimators are applied: one assumes that the redshift is known, and another marginalizes it, taking a specific prior distribution. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

7 pages, 485 KiB

Open AccessProceeding Paper

The Low-Energy Module (LEM): Development of a CubeSat Spectrometer for Sub-MeV Particles and Gamma-Ray Burst Detection

by Riccardo Nicolaidis, Francesco Nozzoli, Giancarlo Pepponi, Pierluigi Bellutti, Evgeny Demenev, Francesco Maria Follega, Roberto Iuppa and Veronica Vilona

Phys. Sci. Forum 2023, 7(1), 21; https://doi.org/10.3390/ECU2023-14055 - 17 Feb 2023

Viewed by 954

Abstract

An accurate flux measurement of low-energy charged particles trapped in the magnetosphere is necessary for space weather characterization and to study the coupling between the lithosphere and magnetosphere, which allows for the investigation of the correlations between seismic events and particle precipitation from [...] Read more.

An accurate flux measurement of low-energy charged particles trapped in the magnetosphere is necessary for space weather characterization and to study the coupling between the lithosphere and magnetosphere, which allows for the investigation of the correlations between seismic events and particle precipitation from Van Allen belts. In this work, the project of a CubeSat space spectrometer, the Low-Energy Module (LEM), is shown. The detector will be able to perform an event-based measurement of the energy, arrival direction, and composition of low-energy charged particles down to 0.1 MeV. Moreover, thanks to a CdZnTe mini-calorimeter, the LEM spectrometer also allows for photon detection in the sub-MeV range, joining the quest for the investigation of the nature of Gamma-ray bursts. The particle identification of the LEM relies on the

Δ E - E

technique performed by thin silicon detectors. This multipurpose spectrometer will fit within a 10 × 10 × 10

{cm}^{3}

CubeSat frame, and it will be constructed as a joint project between the University of Trento, FBK, and INFN-TIFPA. To fulfil the size and mass requirements, an innovative approach, based on active particle collimation, was designed for the LEM; this avoids the heavy/bulky passive collimators of previous space detectors. In this paper, we will present the LEM geometry, its detection concept, and the results from the developed GEANT4 simulation. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

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9 pages, 319 KiB

Open AccessProceeding Paper

Isospin Symmetry Breaking in Non-Perturbative QCD

by Abdel Nasser Tawfik

Phys. Sci. Forum 2023, 7(1), 22; https://doi.org/10.3390/ECU2023-14047 - 16 Feb 2023

Cited by 2 | Viewed by 1011

Abstract

At finite isospin chemical potential

μ_{I}

, the tension between measured decays and partial branching ratios of neutral and charged bosons as functions of dimuon mass squared and the Standard Model (SM) isospin asymmetry can be analyzed in nonperturbative QCD-effective models, for [...] Read more.

At finite isospin chemical potential

μ_{I}

, the tension between measured decays and partial branching ratios of neutral and charged bosons as functions of dimuon mass squared and the Standard Model (SM) isospin asymmetry can be analyzed in nonperturbative QCD-effective models, for instance, the Polyakov linear sigma-model. With almost first-principle derivation of the explicit isospin symmetry breaking, namely,

{\bar{σ}}_{3} = f_{K^{\pm}} - f_{K^{0}}

the isospin sigma field, and

h_{3} = m_{a_{0}}^{2} (f_{K^{\pm}} - f_{K^{0}})

the third generator of the matrix of the explicit symmetry breaking

H = T_{a} h_{a}

.

f_{K^{\pm}}

and

f_{K^{0}}

are decay constants of

K^{\pm}

and

K^{0}

, respectively.

m_{a_{0}}

is the mass of

a_{0}

meson. Accordingly, the QCD phase structure could be extended to finite

μ_{I}

. With the thermal and density dependence of

a_{0}

,

f_{K^{\pm}}

, and

f_{K^{0}}

,

{\bar{σ}}_{3}

and

h_{3}

are accordingly expressed in dependence on the temperatures and the chemical potentials. We find that the resulting critical chiral temperatures

T_{χ}

decrease with the increase in

μ_{B}

and/or

μ_{I}

. We conclude that the (

T_{χ} - μ_{I}

) boundary has almost the same structure as that of the (

T_{χ} - μ_{B}

) plane. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

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5 pages, 239 KiB

Open AccessProceeding Paper

Physical Picture of Electron Spin

by Siva Mythili Gonuguntla

Phys. Sci. Forum 2023, 7(1), 23; https://doi.org/10.3390/ECU2023-14019 - 15 Feb 2023

Viewed by 900

Abstract

Pauli established the standard view that the spin of the electron was a completely abstract non-classical angular momentum that could not be thought of as the rotation of anything. Here, we give a pedagogical presentation of old work by Belifante (1939), recently updated [...] Read more.

Pauli established the standard view that the spin of the electron was a completely abstract non-classical angular momentum that could not be thought of as the rotation of anything. Here, we give a pedagogical presentation of old work by Belifante (1939), recently updated by Ohanian (1986), which shows that, contrary to Pauli’s edict, the spin of the electron can be viewed as the rotational angular momentum in the wave field of the electron. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

6 pages, 3175 KiB

Open AccessProceeding Paper

Escaping the Pair-Instability Mass Gap with the Help of Dark Matter

by Raghav Narasimha, Della Vincent, Arun Kenath and Chandra Sivaram

Phys. Sci. Forum 2023, 7(1), 24; https://doi.org/10.3390/ECU2023-14059 - 7 Mar 2023

Viewed by 1266

Abstract

Black Holes are not expected to form in the mass range of 60 M_⊙ to 130 M_⊙ because of the Pair-Instability Supernova (PISN). However, the recent observational evidence of GW190521 does not comply with the existing theory. Here, we have looked [...] Read more.

Black Holes are not expected to form in the mass range of 60 M_⊙ to 130 M_⊙ because of the Pair-Instability Supernova (PISN). However, the recent observational evidence of GW190521 does not comply with the existing theory. Here, we have looked into the effects of Dark Matter (DM) in the progenitors of PISN in terms of luminosity, lifetime and temperature and have shown that in the presence of DM particles, the progenitors can overcome the PISN stage to collapse into a black hole (BH) as a remnant. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

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6 pages, 1611 KiB

Open AccessProceeding Paper

The Shape of Dark Matter Halos as a Strong Cosmological Probe

by Rémy Koskas and Jean-Michel Alimi

Phys. Sci. Forum 2023, 7(1), 25; https://doi.org/10.3390/ECU2023-14033 - 15 Feb 2023

Viewed by 1170

Abstract

Halo Dark Matter (DM) formation is a complex process, intertwining both gravitational and cosmological nonlinear phenomena. One of the manifestations of this complexity is the shape of the resulting present-day DM halos: simulations and observations show that they are triaxial objects. Interestingly, those [...] Read more.

Halo Dark Matter (DM) formation is a complex process, intertwining both gravitational and cosmological nonlinear phenomena. One of the manifestations of this complexity is the shape of the resulting present-day DM halos: simulations and observations show that they are triaxial objects. Interestingly, those shapes carry cosmological information. We prove that cosmology, and particularly the dark energy model, leaves a lasting trace on the present-day halos and their properties: the overall shape of the DM halo exhibits a different behavior when the DE model is varied. We explain how that can be used to literally “read” the fully nonlinear power spectrum within the halos’ shape at

z = 0

. To that end, we worked with “Dark Energy Universe Simulations” DM halos: DM halos are grewed in three different dark energy models, whose parameters were chosen in agreement with both CMB and SN Ia data. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

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8 pages, 829 KiB

Open AccessProceeding Paper

Reconstruction, Analysis and Constraints of Cosmological Scalar Field ϕCDM Models

by Olga Avsajanishvili and Lado Samushia

Phys. Sci. Forum 2023, 7(1), 26; https://doi.org/10.3390/ECU2023-14060 - 18 Feb 2023

Viewed by 854

Abstract

We studied the following scalar field ϕCDM models: ten quintessence models and seven phantom models. We reconstructed these models using the phenomenological method developed by our group. For each potential, the following ranges were found: (i) model parameters; (ii) EoS parameters; and [...] Read more.

We studied the following scalar field ϕCDM models: ten quintessence models and seven phantom models. We reconstructed these models using the phenomenological method developed by our group. For each potential, the following ranges were found: (i) model parameters; (ii) EoS parameters; and (iii) the initial conditions for differential equations, which describe the dynamics of the universe. Using MCMC analysis, we obtained the constraints of scalar field models by comparing observations for the expansion rate of the universe, the angular diameter distance and the growth rate function, with corresponding data generated for the fiducial ΛCDM model. We applied Bayes statistical criteria to compare scalar field models. To this end, we calculated the Bayes factor, as well as the AIC and BIC information criteria. The results of this analysis show that we could not uniquely identify the preferable scalar field ϕCDM models compared to the fiducial ΛCDM model based on the predicted DESI data, and that the ΛCDM model is a true dark energy model. We investigated scalar field ϕCDM models in the w₀–w_a phase spaces of the CPL-ΛCDM contours. We identified subclasses of quintessence and phantom scalar field models that, in the present epoch: (i) can be distinguished from the ΛCDM model; (ii) cannot be distinguished from the ΛCDM model; and (iii) can be either distinguished or undistinguished from the ΛCDM model. We found that all the studied models can be divided into two classes: models that have attractor solutions and models whose evolution depends on initial conditions. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

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6 pages, 252 KiB

Open AccessProceeding Paper

The Regular Black Hole by Gravitational Decoupling

by Vitalii Vertogradov and Maxim Misyura

Phys. Sci. Forum 2023, 7(1), 27; https://doi.org/10.3390/ECU2023-14058 - 17 Feb 2023

Cited by 2 | Viewed by 922

Abstract

In this paper, we consider using the gravitational decoupling method to obtain a hairy regular black hole which corresponds to the Hayward model. We modify the hairy Schwarzschild solution to obtain the regular Kretschmann scalar. The energy momentum of a new model is [...] Read more.

In this paper, we consider using the gravitational decoupling method to obtain a hairy regular black hole which corresponds to the Hayward model. We modify the hairy Schwarzschild solution to obtain the regular Kretschmann scalar. The energy momentum of a new model is considered, and we show that there is an energy exchange between its parts. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

7 pages, 278 KiB

Open AccessProceeding Paper

Bianchi Type-I Universe in Modified Theory of Gravity

by Bhupendra Kumar Shukla, Rishi Kumar Tiwari and Aroonkumar Beesham

Phys. Sci. Forum 2023, 7(1), 28; https://doi.org/10.3390/ECU2023-14049 - 17 Feb 2023

Viewed by 850

Abstract

In this paper, we have studied an anisotropic Bianchi-I cosmological model in

f (R, T)

gravity. To obtain the exact solutions of the field equations, we have used the condition

σ / θ

to be a function of the scale [...] Read more.

In this paper, we have studied an anisotropic Bianchi-I cosmological model in

f (R, T)

gravity. To obtain the exact solutions of the field equations, we have used the condition

σ / θ

to be a function of the scale factor (IJTP, 54, 2740-2757, 2015). Our model possesses an initial singularity. It initially exhibits decelerating expansion and transits to accelerating expansion at late times. We have also discussed the physical and geometrical properties of the model. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

6 pages, 288 KiB

Open AccessProceeding Paper

Dark Matter Investigation Using Double Beta Decay Experiments

by Francesco Nozzoli and Cinzia Cernetti

Phys. Sci. Forum 2023, 7(1), 29; https://doi.org/10.3390/ECU2023-14056 - 17 Feb 2023

Viewed by 923

Abstract

Nuclei that are unstable with respect to double beta decay are potentially interesting for a novel Dark Matter (DM) direct detection approach. In particular, a Majorana DM fermion inelastically scattering on a double beta unstable nucleus could stimulate its decay. Thanks to the [...] Read more.

Nuclei that are unstable with respect to double beta decay are potentially interesting for a novel Dark Matter (DM) direct detection approach. In particular, a Majorana DM fermion inelastically scattering on a double beta unstable nucleus could stimulate its decay. Thanks to the exothermic nature of the stimulated double beta decay, this detection approach would allow for also investigating light DM fermions, a class of DM candidates that evade the detection capability of the traditional elastic scattering experiments. The upper limits on the nucleus scattering cross sections and the expected signal distribution for different DM masses are shown and compared with the existing data for the case of the ⁷⁶Ge nucleus. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

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6 pages, 738 KiB

Open AccessProceeding Paper

Major Mergers as Possible Drivers of the Galaxy Mass Assembly in the Early Universe: New Insights from ALMA Observations

by Michael Romano

Phys. Sci. Forum 2023, 7(1), 30; https://doi.org/10.3390/ECU2023-14067 - 22 Feb 2023

Viewed by 1057

Abstract

Galaxies are thought to grow through star formation or by interacting with each other. To understand which process dominates, we investigated the contribution of major mergers to the galaxy mass assembly across cosmic time. We made use of recent observations from the ALPINE [...] Read more.

Galaxies are thought to grow through star formation or by interacting with each other. To understand which process dominates, we investigated the contribution of major mergers to the galaxy mass assembly across cosmic time. We made use of recent observations from the ALPINE survey to analyze the morphology and kinematic information provided by the [CII] 158

μ

m line observed in

z \sim 5

star-forming galaxies. We found that 40% of galaxies in that epoch were undergoing merging. By combining our results with studies at lower redshift, we computed the cosmic evolution of the merger fraction, estimating that major mergers could contribute up to 30% to the cosmic star-formation rate density at

z > 4

. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

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6 pages, 261 KiB

Open AccessProceeding Paper

Calculation of the Vacuum Energy Density Using Zeta Function Regularization

by Siamak Tafazoli

Phys. Sci. Forum 2023, 7(1), 31; https://doi.org/10.3390/ECU2023-14053 - 17 Feb 2023

Viewed by 1768

Abstract

This paper presents a theoretical calculation of the vacuum energy density by summing the contributions of all quantum fields’ vacuum states, which turns out to indicate that there seems to be a missing bosonic contribution in order to match the predictions of the [...] Read more.

This paper presents a theoretical calculation of the vacuum energy density by summing the contributions of all quantum fields’ vacuum states, which turns out to indicate that there seems to be a missing bosonic contribution in order to match the predictions of the current cosmological models and all observational data to date. The basis for this calculation is a new Zeta function regularization method used to tame the infinities present in the improper integrals of power functions. The paper also presents a few other contributions in the area of vacuum energy. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

6 pages, 1315 KiB

Open AccessProceeding Paper

Constraining Star-Formation Driven Outflows in Local Dwarf Galaxies with Herschel†

by Michael Romano

Phys. Sci. Forum 2023, 7(1), 32; https://doi.org/10.3390/ECU2023-14072 - 22 Feb 2023

Viewed by 1223

Abstract

Galactic feedback (i.e., outflows) plays a fundamental role in regulating galaxy formation and evolution. We investigate the physical properties of galactic outflows in a sample of 29 local low-metallicity dwarf galaxies drawn from the Dwarf Galaxy Survey. We make use of Herschel/PACS archival [...] Read more.

Galactic feedback (i.e., outflows) plays a fundamental role in regulating galaxy formation and evolution. We investigate the physical properties of galactic outflows in a sample of 29 local low-metallicity dwarf galaxies drawn from the Dwarf Galaxy Survey. We make use of Herschel/PACS archival data to detect outflows in the broad wings of observed [CII] 158 μm line profiles. We detect outflowing gas in 1/3 of the sample, and in the average galaxy population through line stacking. We find typical mass-loading factors (i.e., outflow efficiencies) of the order of unity. Outflow velocities are larger than the velocities required from gas to escape the gravitational potential of our targets, suggesting that a significant amount of gas and dust is brought out of their halos. Our results will be used as input for chemical models, posing new constraints on the processes of dust production/destruction in the interstellar medium of galaxies. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

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4 pages, 240 KiB

Open AccessProceeding Paper

A Class of 5D Inhomogeneous Models with a Cosmological Constant

by Pantelis S. Apostolopoulos

Phys. Sci. Forum 2023, 7(1), 33; https://doi.org/10.3390/ECU2023-14064 - 18 Feb 2023

Viewed by 748

Abstract

In this work, we would like to address the problem of the effect of bulk matter on the brane cosmological evolution in a general way. We assume that the spatial part of the brane metric is not maximally symmetric, and is, therefore, spatially [...] Read more.

In this work, we would like to address the problem of the effect of bulk matter on the brane cosmological evolution in a general way. We assume that the spatial part of the brane metric is not maximally symmetric, and is, therefore, spatially inhomogeneous. However, we retain the conformal flatness property of the standard cosmological model (FRW), i.e., the Weyl tensor of the induced 4D geometry is zero. We refer to it as Spatially Inhomogeneous Irrotational (SII) brane. It is shown that the model can be regarded as the 5D generalization of the SII spacetimes found recently. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

6 pages, 1010 KiB

Open AccessProceeding Paper

LRS Bianchi-I Transit Cosmological Models in f(R,T) Gravity

by Siwaphiwe Jokweni, Vijay Singh, Aroonkumar Beesham and Binaya Kumar Bishi

Phys. Sci. Forum 2023, 7(1), 34; https://doi.org/10.3390/ECU2023-14062 - 18 Feb 2023

Cited by 1 | Viewed by 972

Abstract

A locally rotationally symmetric Bianchi-I model is explored both in general relativity and in f(R,T) gravity, where R is the Ricci scalar and T is the trace of the energy-momentum tensor. Solutions have been found by means of a special Hubble parameter, yielding [...] Read more.

A locally rotationally symmetric Bianchi-I model is explored both in general relativity and in f(R,T) gravity, where R is the Ricci scalar and T is the trace of the energy-momentum tensor. Solutions have been found by means of a special Hubble parameter, yielding a hyperbolic hybrid scale factor. Some geometrical parameters have been studied. A comparison is made between solutions in general relativity and in f(R,T) gravity, where in both the theories, the models exhibit rich behaviour from stiff matter to quintessence, phantom, then later mimicking the cosmological constant, depending on some parameters. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

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7 pages, 616 KiB

Open AccessProceeding Paper

On Cosmological Inflation in Palatini F(R,ϕ) Gravity

by Mahmoud AlHallak

Phys. Sci. Forum 2023, 7(1), 35; https://doi.org/10.3390/ECU2023-14048 - 17 Feb 2023

Cited by 1 | Viewed by 767

Abstract

Single field inflationary models are investigated within Palatini quadratic gravity, represented by

R + α R^{2}

, along with a non-minimal coupling of the form

f (ϕ) R

between the inflaton field

ϕ

and the gravity. The treatment is performed [...] Read more.

Single field inflationary models are investigated within Palatini quadratic gravity, represented by

R + α R^{2}

, along with a non-minimal coupling of the form

f (ϕ) R

between the inflaton field

ϕ

and the gravity. The treatment is performed in the Einstein frame, where the minimal coupling to gravity is recovered through conformal transformation. We consider various limits of the model with different inflationary scenarios characterized as canonical slow-roll inflation in the limit

α {\dot{ϕ}}^{2} ≪ (1 + f (ϕ))

, constant-roll k-inflation for

α ≪ 1

, and slow-roll K-inflation for

α ≫ 1

. A cosine and exponential potential are examined with the limits mentioned above and different well-motivated non-minimal couplings to gravity. We compare the theoretical results, exemplified by the tensor-to-scalar r ratio and spectral index

n_{s}

, with the recent observational results of Planck 2018 and BICEP/Keck. Furthermore, we include the results of a new study forecast precision with which

n_{s}

and r can be constrained by currently envisaged observations, including CMB (Simons Observatory, CMB-S4, and LiteBIRD). Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

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7 pages, 272 KiB

Open AccessProceeding Paper

Discretized Finsler Structure: An Approach to Quantizing the First Fundamental Form

by Abdel Nasser Tawfik

Phys. Sci. Forum 2023, 7(1), 36; https://doi.org/10.3390/ECU2023-14066 - 18 Feb 2023

Cited by 1 | Viewed by 1256

Abstract

Whether an algebraic or a geometric or a phenomenological prescription is applied, the first fundamental form is unambiguously related to the modeling of the curved spacetime. Accordingly, we assume that the possible quantization of the first fundamental form could be proposed. For precise [...] Read more.

Whether an algebraic or a geometric or a phenomenological prescription is applied, the first fundamental form is unambiguously related to the modeling of the curved spacetime. Accordingly, we assume that the possible quantization of the first fundamental form could be proposed. For precise accurate measurement of the first fundamental form

d s^{2} = g_{μ ν} d x^{μ} d x^{ν}

, the author derived a quantum-induced revision of the fundamental tensor. To this end, the four-dimensional Riemann manifold is extended to the eight-dimensional Finsler manifold, in which the quadratic restriction on the length measure is relaxed, especially in the relativistic regime; the minimum measurable length could be imposed ad hoc on the Finsler structure. The present script introduces an approach to quantize the fundamental tensor and first fundamental form. Based on gravitized quantum mechanics, the resulting relativistic generalized uncertainty principle (RGUP) is directly imposed on the Finsler structure,

F ({\hat{x}}_{0}^{μ}, {\hat{p}}_{0}^{ν})

, which is obviously homogeneous to one degree in

{\hat{p}}_{0}^{μ}

. The momentum of a test particle with mass

\bar{m} = m / m_{p}

with

m_{p}

is the Planck mass. This unambiguously results in the quantized first fundamental form

d {\tilde{s}}^{2} = [1 + (1 + 2 β {\hat{p}}_{0}^{ρ} {\hat{p}}_{0 ρ}) {\bar{m}}^{2} (| \ddot{x} {| / A)}^{2}] g_{μ ν} d {\hat{x}}^{μ} d {\hat{x}}^{ν}

, where

\ddot{x}

is the proper spacelike four-acceleration,

A

is the maximal proper acceleration, and

β

is the RGUP parameter. We conclude that an additional source of curvature associated with the mass

\bar{m}

, whose test particle is accelerated at

| \ddot{x} |

, apparently emerges. Thereby, quantizations of the fundamental tensor and first fundamental form are feasible. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

10 pages, 271 KiB

Open AccessProceeding Paper

The Status of Geometry and Matter in the Reinterpreted WdW Equation

by Avadhut V. Purohit

Phys. Sci. Forum 2023, 7(1), 37; https://doi.org/10.3390/ECU2023-14097 - 2 Mar 2023

Viewed by 1203

Abstract

This paper shows that the field defined by the Wheeler–DeWitt equation for pure gravity is neither a standard gravitational field nor the field representing a particular universe. The theory offers a unified description of geometry and matter, with geometry being fundamental. The quantum [...] Read more.

This paper shows that the field defined by the Wheeler–DeWitt equation for pure gravity is neither a standard gravitational field nor the field representing a particular universe. The theory offers a unified description of geometry and matter, with geometry being fundamental. The quantum theory possesses gravitational decoherence when the signature of

R^{(3)}

changes. The quantum theory resolves singularities dynamically. Application to the FLRW

κ = 0

shows the creation of local geometries during quantum evolution. The 3-metric is modified near the classical singularity in the case of the Schwarzschild geometry. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

7 pages, 1118 KiB

Open AccessProceeding Paper

Impact of Particle Creation in Rastall Gravity

by Binaya Kumar Bishi, Pratik Vijay Lepse and Aroonkumar Beesham

Phys. Sci. Forum 2023, 7(1), 38; https://doi.org/10.3390/ECU2023-14057 - 17 Feb 2023

Viewed by 1135

Abstract

We investigated the Friedmann–Lemaitre–Robertson–Walker (FLRW) cosmological models within the framework of Rastall gravity incorporating particle creation. The modified field equations for Rastall gravity are derived, and exact solutions are obtained under various types of scale factors. The qualitative behaviour of our solutions depends [...] Read more.

We investigated the Friedmann–Lemaitre–Robertson–Walker (FLRW) cosmological models within the framework of Rastall gravity incorporating particle creation. The modified field equations for Rastall gravity are derived, and exact solutions are obtained under various types of scale factors. The qualitative behaviour of our solutions depends on the Rastall coupling parameter

ψ = k λ

. Following the literature, we have restricted the Rastall coupling parameter

ψ

(k = 1)

to the range

- 0.0001 < ψ < 0.0007

at 68% CL from CMB+BAO data. Furthermore, we have discussed the distinct physical behaviour of the derived models in detail. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

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5 pages, 253 KiB

Open AccessProceeding Paper

Highly Accreting Supermassive Black Holes as Eddington Standard Candles

by Paola Marziani

Phys. Sci. Forum 2023, 7(1), 39; https://doi.org/10.3390/ECU2023-14040 - 16 Feb 2023

Cited by 1 | Viewed by 798

Abstract

Supermassive black holes accreting matter at very high, perhaps even super-Eddington rates appear in the sky as a special class of luminous active galactic nuclei. The Eigenvector 1/quasar main sequence parameter space allows for the definition of easy-to-implement selection criteria in the rest-frame [...] Read more.

Supermassive black holes accreting matter at very high, perhaps even super-Eddington rates appear in the sky as a special class of luminous active galactic nuclei. The Eigenvector 1/quasar main sequence parameter space allows for the definition of easy-to-implement selection criteria in the rest-frame visual and UV spectral ranges. The systematic trends of the main sequence are believed to reflect a change in accretion modes: at high accretion rates, an optically thick, geometrically thick, advection-dominated accretion disk is expected to develop. Even if the physical processes occurring in advection-dominated accretion flows are still not fully understood, a robust inference from the models—supported by a wealth of observational data—is that these extreme quasars should radiate at maximum radiative efficiency for a given black hole mass. A key empirical result is that lines emitted by ionic species of low ionization are mainly broadened because of virial motions even in such extreme radiative conditions. “Virial luminosity” estimates from emission line widths then become possible, in analogy to the scaling laws defined for galaxies. In this contribution, we summarize aspects related to their structure and to the complex interplay between accretion flow and line emitting region, involving dynamics of the line emitting regions, metal content, and spectral energy distribution. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

8 pages, 278 KiB

Open AccessProceeding Paper

Gravitational Spin Hall Effect in Curves Spacetimes

by Pravin Kumar Dahal

Phys. Sci. Forum 2023, 7(1), 40; https://doi.org/10.3390/ECU2023-14050 - 17 Feb 2023

Viewed by 936

Abstract

Geometric optics approximation sufficiently describes the effects in the near-earth environment, and Faraday rotation is purely a reference frame effect in this limit. A simple encoding procedure could mitigate the Faraday phase error. However, the framework of geometric optics is not sufficient to [...] Read more.

Geometric optics approximation sufficiently describes the effects in the near-earth environment, and Faraday rotation is purely a reference frame effect in this limit. A simple encoding procedure could mitigate the Faraday phase error. However, the framework of geometric optics is not sufficient to describe the propagation of waves of large but finite frequencies. So, we outline the technique to solve the equations for the propagation of an electromagnetic wave up to the subleading order geometric optics expansion in curved spacetimes. For this, we first need to construct a set of parallel propagated null tetrads in curved spacetimes. Then we should use the parallel propagated tetrad to solve the modified trajectory equation. The wavelength-dependent deviation of the electromagnetic waves is observed, which gives the mathematical description of the gravitational spin Hall effect. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

6 pages, 249 KiB

Open AccessProceeding Paper

Construction of Discrete Symmetries Using the Pauli Algebra Form of the Dirac Equation

by Avraham Nofech

Phys. Sci. Forum 2023, 7(1), 41; https://doi.org/10.3390/ECU2023-14054 - 17 Feb 2023

Viewed by 1030

Abstract

Two equations whose variables take values in the Pauli algebra of complex quaternions are shown to be equivalent to the standard Dirac equation and its Hermitian conjugate taken together. They are transformed one into the other by an outer automorphism of the Pauli [...] Read more.

Two equations whose variables take values in the Pauli algebra of complex quaternions are shown to be equivalent to the standard Dirac equation and its Hermitian conjugate taken together. They are transformed one into the other by an outer automorphism of the Pauli algebra. Given a solution to the Dirac equation, a new solution is obtained by multiplying it on the right by one of the 16 matrices of the Pauli group. This defines a homomorphism from the Pauli group into the group of discrete symmetries, whose kernel is a cyclic group of order four. The group of discrete symmetries is shown to be the Klein four-group consisting of four elements: the identity Id; the charge conjugation symmetry C; the mass inversion symmetry M; and their composition in either order, CM = MC. The mass inversion symmetry inverts the sign of the mass, leaving the electric charge unchanged. The outer “bar-star” automorphism is identified with the parity operation, resulting in proof of CPT = M or, equivalently, CPTM = Identity. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

6 pages, 1711 KiB

Open AccessProceeding Paper

Novel Concepts of Nuclear Physics in a Neutron Star Environment

by Vlasios Petousis, Martin Veselský, Jozef Leja, Ch. C. Moustakidis, G. A. Souliotis, A. Bonasera and Laura Navarro

Phys. Sci. Forum 2023, 7(1), 42; https://doi.org/10.3390/ECU2023-14051 - 17 Feb 2023

Viewed by 964

Abstract

Neutron stars are like nuclear physics laboratories, providing a unique opportunity to apply and search for new physics. In that spirit, we explored novel concepts of nuclear physics studied in a neutron star environment. Firstly, we investigated the reported 17 MeV boson, which [...] Read more.

Neutron stars are like nuclear physics laboratories, providing a unique opportunity to apply and search for new physics. In that spirit, we explored novel concepts of nuclear physics studied in a neutron star environment. Firstly, we investigated the reported 17 MeV boson, which has been proposed as an explanation to the

^{8}

Be,

^{4}

He and

^{12}

C anomaly, in the context of its possible influence on the neutron star structure, defining a universal Equation of State. Next, we investigated the synthesis of hyper-heavy elements under conditions simulating the neutron star environment. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

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9 pages, 914 KiB

Open AccessProceeding Paper

A Rotating Model of a Light Speed Expanding Hubble-Hawking Universe

by U. V. Satya Seshavatharam and S. Lakshminarayana

Phys. Sci. Forum 2023, 7(1), 43; https://doi.org/10.3390/ECU2023-14065 - 18 Feb 2023

Cited by 1 | Viewed by 1554

Abstract

Based on light speed expansion, a modified red shift formula, a scaled Hawking’s black hole temperature formula, the super gravity of galactic baryon matter and baby Planck ball, in our recent publications we have clearly established a novel model of quantum cosmology. In [...] Read more.

Based on light speed expansion, a modified red shift formula, a scaled Hawking’s black hole temperature formula, the super gravity of galactic baryon matter and baby Planck ball, in our recent publications we have clearly established a novel model of quantum cosmology. In this contribution, we appeal for the need of reviewing the basics of Lambda cosmology in the context of cosmic quantum spin. We would like to emphasize the point that spin is a basic property of quantum mechanics, and one who is interested in developing quantum models of cosmology must think about cosmic rotation. It may also be noted that, without a radial in-flow of matter in all directions towards one specific point, one cannot expect a big crunch and without a big crunch one cannot expect a big bang. Really, if there was a “big bang” in the past, with reference to the formation of the big bang as predicted by General Theory of Relativity (GTR) and with reference to the cosmic rate of expansion that might have taken place simultaneously in all directions at a “naturally selected rate” about the point of big bang, the “point” of the big bang can be considered as the characteristic reference point of cosmic expansion in all directions. Thinking in this way, either the point of big bang or baby Planck ball can be considered as a possible centre of cosmic evolution. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

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11 pages, 667 KiB

Open AccessProceeding Paper

Quantum Gravitational Non-Singular Tunneling Wavefunction Proposal

by Meysam Motaharfar and Parampreet Singh

Phys. Sci. Forum 2023, 7(1), 44; https://doi.org/10.3390/ECU2023-14101 - 2 Mar 2023

Cited by 2 | Viewed by 1616

Abstract

It has recently been shown that the tunneling wavefunction proposal is consistent with loop quantum geometry corrections, including both holonomy and inverse scale factor corrections, in the gravitational part of a spatially closed isotropic model with a positive cosmological constant. However, in the [...] Read more.

It has recently been shown that the tunneling wavefunction proposal is consistent with loop quantum geometry corrections, including both holonomy and inverse scale factor corrections, in the gravitational part of a spatially closed isotropic model with a positive cosmological constant. However, in the presence of inflationary potential, the initial singularity is kinetic-dominated, and the effective minisuperspace potential again diverges at the zero scale factor. As the wavefunction in loop quantum cosmology cannot increase towards the zero scale factor, the tunneling wavefunction seems incompatible. We show that consistently including inverse scale factor modifications, in scalar field Hamiltonian, changes the effective potential into a barrier potential, allowing the tunneling proposal. We also discuss the potential quantum instability of the cyclic universe, resulting from tunneling. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

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7 pages, 262 KiB

Open AccessProceeding Paper

Gauged (Super)Conformal Models

by Delaram Mirfendereski

Phys. Sci. Forum 2023, 7(1), 45; https://doi.org/10.3390/ECU2023-14052 - 17 Feb 2023

Viewed by 821

Abstract

Superconformal mechanics describes superparticle dynamics in near-horizon geometries of supersymmetric black holes. We systematically study the minimal compatible set of constraints required for a gauged superconformal symmetry. Our study uncovers classes of sigma models, which are only scale invariant in their ungauged form [...] Read more.

Superconformal mechanics describes superparticle dynamics in near-horizon geometries of supersymmetric black holes. We systematically study the minimal compatible set of constraints required for a gauged superconformal symmetry. Our study uncovers classes of sigma models, which are only scale invariant in their ungauged form and become fully conformal invariant only after gauging. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

4 pages, 242 KiB

Open AccessProceeding Paper

Conformal Symmetries of the Strumia–Tetradis’ Metric

by Pantelis S. Apostolopoulos and Christos Tsipogiannis

Phys. Sci. Forum 2023, 7(1), 46; https://doi.org/10.3390/ECU2023-14100 - 2 Mar 2023

Viewed by 1007

Abstract

In a recent paper, a new conformally flat metric was introduced, describing an expanding scalar field in a spherically symmetric geometry. The spacetime can be interpreted as a Schwarzschild-like model with an apparent horizon surrounding the curvature singularity. For the above metric, we [...] Read more.

In a recent paper, a new conformally flat metric was introduced, describing an expanding scalar field in a spherically symmetric geometry. The spacetime can be interpreted as a Schwarzschild-like model with an apparent horizon surrounding the curvature singularity. For the above metric, we present the complete conformal Lie algebra consisting of a six-dimensional subalgebra of isometries (Killing Vector Fields or KVFs) and nine proper conformal vector fields (CVFs). An interesting aspect of our findings is that there exists a gradient (proper) conformal symmetry (i.e., its bivector F_ab vanishes) which verifies the importance of gradient symmetries in constructing viable cosmological models. In addition, the 9-dimensional conformal algebra implies the existence of constants of motion along null geodesics that allow us to determine the complete solution of null geodesic equations. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

8 pages, 476 KiB

Open AccessProceeding Paper

Bose-Einstein Condensate in Synchronous Coordinates

by Boris E. Meierovich

Phys. Sci. Forum 2023, 7(1), 47; https://doi.org/10.3390/ECU2023-14121 - 6 Mar 2023

Viewed by 990

Abstract

Analytical spherically symmetric static solution to the set of Einstein and Klein-Gordon equations in a synchronous reference frame is considered. In a synchronous reference frame, a static solution exists in the ultrarelativistic limit

p = - ε / 3

. Pressure p is [...] Read more.

Analytical spherically symmetric static solution to the set of Einstein and Klein-Gordon equations in a synchronous reference frame is considered. In a synchronous reference frame, a static solution exists in the ultrarelativistic limit

p = - ε / 3

. Pressure p is negative when matter tends to contract. The solution pretends to describe a collapsed black hole. The balance at the boundary with dark matter ensures the static solution for a black hole. There is a spherical layer inside a black hole between two “gravitational” radii

r_{g}

and

r_{h} > r_{g}

, where the solution exists, but it is not unique. In a synchronous reference frame,

\det g_{i k}

and

g^{r r}

do not change signs. The non-uniqueness of solutions with boundary conditions at

r = r_{g}

and

r = r_{h}

makes it possible to find the gravitational field both inside and outside a black hole. The synchronous reference frame allows one to find the remaining mass of the condensate. In the model “

λ {|ψ|}^{4}

”, total mass

M = 3 (c^{2} / 2 k) r_{h}

is three times that of what a distant observer sees. This gravitational mass defect is spent for bosons to be in the bound ground state, and for the balance between elasticity and density of the condensate. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

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7 pages, 262 KiB

Open AccessProceeding Paper

Monism of Nonlocal Matterspace with Instant All-Unity Instead of Particle–Field Duality with Retarded Interactions

by Igor Bulyzhenkov

Phys. Sci. Forum 2023, 7(1), 48; https://doi.org/10.3390/ECU2023-14031 - 15 Feb 2023

Viewed by 760

Abstract

The metric self-organization of matterspace–time implies a nonlocal correlation of its affine connections and the fulfillment of the volumetric conservation of energy–momentum under shifts in coordinate time. Geodesic forces or accelerations in metric fields of general relativity correspond to local pushes by the [...] Read more.

The metric self-organization of matterspace–time implies a nonlocal correlation of its affine connections and the fulfillment of the volumetric conservation of energy–momentum under shifts in coordinate time. Geodesic forces or accelerations in metric fields of general relativity correspond to local pushes by the Lomonosov gravitational liquid but not to the retarded interactions between distant bodies. The mathematics of Russian Cosmism for the monistic all-unity of ethereal matter–space with the continuous distribution of mass–energy replaces Newtonian gravity ‘from there to here’ with the local kinetic stresses ‘from here to there’ due to the spatial asymmetry of inertial densities within a nonlocal whole. The inverse square law for ethereal pushes of concentrated (visible) masses can be controlled locally by a subtle resonant intervention into their polarized densities. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

14 pages, 1803 KiB

Open AccessProceeding Paper

Nonsingular Bouncing Model in Closed and Open Universe

by Manabendra Sharma, Shankar Dayal Pathak and Shiyuan Li

Phys. Sci. Forum 2023, 7(1), 49; https://doi.org/10.3390/ECU2023-14035 - 17 Feb 2023

Viewed by 1043

Abstract

We investigate the background dynamics of a class of models with noncanonical scalar field and matter both in Friedmann Lemaitre Robertson Walker (FLRW) closed and open spacetime. The detailed dynamical system analysis is carried out in a bouncing scenario. Cosmological solutions satisfying the [...] Read more.

We investigate the background dynamics of a class of models with noncanonical scalar field and matter both in Friedmann Lemaitre Robertson Walker (FLRW) closed and open spacetime. The detailed dynamical system analysis is carried out in a bouncing scenario. Cosmological solutions satisfying the stability and bouncing conditions are obtained using the tools of the dynamical system. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

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6 pages, 1091 KiB

Open AccessProceeding Paper

On the Field Strength of Vacuum Energy and the Emergence of Mass

by Mohammed B. Al-Fadhli

Phys. Sci. Forum 2023, 7(1), 50; https://doi.org/10.3390/ECU2023-14104 - 3 Mar 2023

Viewed by 3056

Abstract

Large inconsistencies in the outcome of precise measurements of Newtonian gravitational ‘constant’ were identified throughout more than three hundred experiments conducted up to date. This paper illustrates the dependency of the Newtonian gravitational parameter on the curvature of the background and the associated [...] Read more.

Large inconsistencies in the outcome of precise measurements of Newtonian gravitational ‘constant’ were identified throughout more than three hundred experiments conducted up to date. This paper illustrates the dependency of the Newtonian gravitational parameter on the curvature of the background and the associated field strength of vacuum energy. Additionally, the derived interaction field equations show that boundary interactions and spin-spin correlations of vacuum and conventional energy densities contribute to the emergence of mass. Experimental conditions are recommended to achieve consistent outcomes of the parameter precision measurements, which can directly falsify or provide confirmations to the presented field equations. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

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8 pages, 1915 KiB

Open AccessProceeding Paper

The GRB Afterglows Flowchart

by Esma Zouaoui and Noureddine Mebarki

Phys. Sci. Forum 2023, 7(1), 51; https://doi.org/10.3390/ECU2023-14045 - 16 Feb 2023

Viewed by 803

Abstract

In this paper, we present a flowchart of the Gamma Ray Burst (GRB) afterglows, aiming to create a numerical FORTRAN code. Considering several proposed models, the hydrodynamic evolution describing the external shock of the jet with the environment surrounding the GRB source or [...] Read more.

In this paper, we present a flowchart of the Gamma Ray Burst (GRB) afterglows, aiming to create a numerical FORTRAN code. Considering several proposed models, the hydrodynamic evolution describing the external shock of the jet with the environment surrounding the GRB source or the Interstellar medium is discussed. A comparison of the results and data, considering the synchrotron emission as a basic mechanism for the radiation part, was also carried out. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

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7 pages, 1331 KiB

Open AccessProceeding Paper

The Morphology of the Active Galactic Nucleus and its Impact on Accretion Flows and Relativistic Jets

by Mohammed B. Al-Fadhli

Phys. Sci. Forum 2023, 7(1), 52; https://doi.org/10.3390/ECU2023-14026 - 15 Feb 2023

Viewed by 984

Abstract

The G2 gas cloud motion data and the scarcity of observations on the event horizon-scale distances have challenged the comprehensiveness of the central supermassive black hole model. In addition, the recent Planck Legacy 2018 release has confirmed the existence of an enhanced lensing [...] Read more.

The G2 gas cloud motion data and the scarcity of observations on the event horizon-scale distances have challenged the comprehensiveness of the central supermassive black hole model. In addition, the recent Planck Legacy 2018 release has confirmed the existence of an enhanced lensing amplitude in the cosmic microwave background power spectra, which prefers a positively curved early Universe with a confidence level higher than 99%. This study investigates the impact of the background curvature and its evolution over conformal time on the formation and morphological evolution of central compact objects and the consequent effect on their host galaxies. The formation of a galaxy from the collapse of a supermassive gas cloud in the early Universe is modelled based on interaction field equations as a 4D relativistic cloud-world that flows and spins through a 4D conformal bulk of a primordial positive curvature considering the preference of the Planck release. Owing to the curved background, the derived model reveal that the galaxy and its core are formed at the same process by undergoing a forced vortex formation with a central event horizon leading to opposite vortices (traversable wormholes) that spatially shrink while evolving in the conformal time. The model shows that the accretion flow into the supermassive compact objects only occurs at the central event horizon of the two opposite vortices while their other ends eject relativistic jets. The simulation of the early bulk curvature evolution into the present spatial flatness demonstrated the fast orbital speed of outer stars owing to external fields exerted on galaxies. Furthermore, the gravitational potential of the early curved bulk contributes to galaxy formation while the present spatial flatness deprives the bulk potential which can contribute to galaxy quenching. Accordingly, the model can explain the relativistic jet generation and the G2 gas cloud motion if its orbit is around one of the vortices but at a distance from the central event horizon. Finally, the formation of a galaxy and its core simultaneously could elucidate the growth of the supermassive compact galaxy cores to a mass of ~10⁹ M_⊙ at

\leq 6 %

of the current Universe age. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

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7 pages, 749 KiB

Open AccessProceeding Paper

Cosmological Properties of the Cosmic Web

by Majd Shalak and Jean-Michel Alimi

Phys. Sci. Forum 2023, 7(1), 53; https://doi.org/10.3390/ECU2023-14046 - 16 Feb 2023

Viewed by 1260

Abstract

In this paper, we study the dynamical and statistical properties of the cosmic web and investigate their ability to infer the corresponding cosmological model. Our definition of the cosmic web is based on the local dimensionality of the gravitational collapse that classifies the [...] Read more.

In this paper, we study the dynamical and statistical properties of the cosmic web and investigate their ability to infer the corresponding cosmological model. Our definition of the cosmic web is based on the local dimensionality of the gravitational collapse that classifies the cosmic web into four categories: voids, walls, filaments, and nodes. Our results show that each category has its specific non-Gaussian evolution over time and that these non-Gaussianities depend on the cosmological parameters. Nonetheless, the non-Gaussianities in each category exist even at early epochs when the matter field has a Gaussian distribution. Additionally, by using deep learning techniques, we show that leveraging the cosmic web information engenders an improved inference of cosmological parameters, when compared to merely using the matter field. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

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7 pages, 306 KiB

Open AccessProceeding Paper

The Bound of the Non-Commutative Parameter Based on Gravitational Measurements

by Abdellah Touati and Slimane Zaim

Phys. Sci. Forum 2023, 7(1), 54; https://doi.org/10.3390/ECU2023-14061 - 18 Feb 2023

Viewed by 871

Abstract

In this paper, we investigate the four classical tests of general relativity in the non-commutative (NC) gauge theory of gravity. Using the Seiberg–Witten (SW) map and the star product, we calculate the deformed metric components

{\hat{g}}_{μν} (r, Θ)

[...] Read more.

In this paper, we investigate the four classical tests of general relativity in the non-commutative (NC) gauge theory of gravity. Using the Seiberg–Witten (SW) map and the star product, we calculate the deformed metric components

{\hat{g}}_{μν} (r, Θ)

of the Schwarzschild black hole (SBH). The use of this deformed metric enables us to calculate the gravitational periastron advance of mercury, the red shift, the deflection of light, and time delays in the NC spacetime. Our results for the NC prediction of the gravitational deflection of light and time delays show a newer behavior than the classical one. As an application, we use a typical primordial black hole to estimate the NC parameter

Θ

, where our results show

Θ^{phy} \approx 10^{- 34} m

for the gravitational red shift, the deflection of light, and time delays at the final stage of inflation, and

Θ^{phy} \approx 10^{- 31} m

for the gravitational periastron advance of some planets from our solar system. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

5 pages, 993 KiB

Open AccessProceeding Paper

Gravitational, Electromagnetic and Quantum Interaction: From String to Cloud Theory

by Mohammed B. Al-Fadhli

Phys. Sci. Forum 2023, 7(1), 55; https://doi.org/10.3390/ECU2023-14063 - 18 Feb 2023

Viewed by 1022

Abstract

The recent Planck Legacy 2018 release verified the presence of an enhanced lensing amplitude in the power spectra of the cosmic microwave background with a confidence level of over 99%, which implies that the early Universe had a positive curvature. In this study, [...] Read more.

The recent Planck Legacy 2018 release verified the presence of an enhanced lensing amplitude in the power spectra of the cosmic microwave background with a confidence level of over 99%, which implies that the early Universe had a positive curvature. In this study, the curvature of the early Universe is regarded as the curvature of 4D conformal bulk while celestial objects that induce a localized curvature in the bulk are considered as 4D relativistic cloud-worlds. Likewise, quantum fields are considered as 4D relativistic quantum clouds that are affected by the curvature of the bulk as a manifestation of gravity. This approach could eliminate the singularities and satisfy the conditions of a conformal invariance theory. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

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1911 KiB

Open AccessProceeding Paper

Entangled Dual Universe

by Mohammed B. Al-Fadhli

Phys. Sci. Forum 2023, 7(1), 56; https://doi.org/10.3390/ECU2023-14102 - 2 Mar 2023

Viewed by 1220

Abstract

Advances in cosmology and astronomical observations have brought to light significant tensions and uncertainties within the current model of cosmology, which assumes a spatially flat Universe and is known as the ΛCDM model. Moreover, the Planck Legacy 2018 release has preferred that the [...] Read more.

Advances in cosmology and astronomical observations have brought to light significant tensions and uncertainties within the current model of cosmology, which assumes a spatially flat Universe and is known as the ΛCDM model. Moreover, the Planck Legacy 2018 release has preferred that the early Universe had a positive curvature with a confidence level more than 99%. This study reports a quantum mechanism that could potentially replace the concept of dark matter/energy by taking into the account the primordial curvature while generating the present-day spatial flatness. The approach incorporates the primordial curvature as the background curvature to extend the field equations into brane-world gravity. It utilizes a new wavefunction of the Universe that propagates in the bulk with respect to the scale factor and curvature radius of the early Universe upon the emission of the cosmic microwave background. The resulting wavefunction yields both positive and negative solutions, revealing the presence of a pair of entangled wavefunctions as a manifestation of the creation of matter and antimatter sides of the Universe. The wavefunction shows a nascent hyperbolic expansion away from early energy in opposite directions followed by a first decelerating expansion phase during the first ~10 Gyr and a subsequent accelerating expansion phase in reverse directions. During the second phase, both Universe sides are free-falling towards each other under gravitational acceleration. The simulation of the predicted background curvature evolution shows that the early curved background caused galaxies to experience external fields, resulting in the fast orbital speed of outer stars. Finally, the wavefunction predicts that the Universe will eventually undergo a rapid contraction phase resulting in a Big Crunch, which reveals a cyclic Universe. Full article

(This article belongs to the Proceedings of The 2nd Electronic Conference on Universe)

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