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6 pages, 201 KiB

Open AccessEditorial

Origins and Natures of Inflation, Dark Matter and Dark Energy

by Kazuharu Bamba

Universe 2024, 10(3), 144; https://doi.org/10.3390/universe10030144 - 15 Mar 2024

Viewed by 1191

Abstract

Various precise cosmological observations, e [...] Full article

(This article belongs to the Special Issue Origins and Natures of Inflation, Dark Matter and Dark Energy)

Research

Jump to: Editorial, Review

14 pages, 3773 KiB

Open AccessArticle

Design and Construction of a Variable-Angle Three-Beam Stimulated Resonant Photon Collider toward eV-Scale ALP Search

by Takumi Hasada, Kensuke Homma and Yuri Kirita

Universe 2023, 9(8), 355; https://doi.org/10.3390/universe9080355 - 29 Jul 2023

Cited by 1 | Viewed by 717

Abstract

We aim to search for axion-like particles in the eV mass range using a variable-angle stimulated resonance photon collider (SRPC) with three intense laser beams. By changing angle of incidence of the three beams, the center-of-mass-system collision energy can be varied and the [...] Read more.

We aim to search for axion-like particles in the eV mass range using a variable-angle stimulated resonance photon collider (SRPC) with three intense laser beams. By changing angle of incidence of the three beams, the center-of-mass-system collision energy can be varied and the eV mass range can be continuously searched for. In this paper, we present the design and construction of such a variable-angle three-beam SRPC (

^{t} SRPC

), the verification of the variable-angle mechanism using a calibration laser, and realistic sensitivity projections for searches in the near future. Full article

(This article belongs to the Special Issue Origins and Natures of Inflation, Dark Matter and Dark Energy)

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16 pages, 2017 KiB

Open AccessArticle

Pilot Search for Axion-Like Particles by a Three-Beam Stimulated Resonant Photon Collider with Short Pulse Lasers

by Fumiya Ishibashi, Takumi Hasada, Kensuke Homma, Yuri Kirita, Tsuneto Kanai, ShinIchiro Masuno, Shigeki Tokita and Masaki Hashida

Universe 2023, 9(3), 123; https://doi.org/10.3390/universe9030123 - 28 Feb 2023

Cited by 3 | Viewed by 1147

Abstract

Toward the systematic search for axion-like particles in the eV mass range, we proposed the concept of a stimulated resonant photon collider by focusing three short pulse lasers into a vacuum. In order to realize such a collider, we have performed a proof-of-principle [...] Read more.

Toward the systematic search for axion-like particles in the eV mass range, we proposed the concept of a stimulated resonant photon collider by focusing three short pulse lasers into a vacuum. In order to realize such a collider, we have performed a proof-of-principle experiment with a set of large incident angles between three beams to overcome the expected difficulty to ensure the space–time overlap between short pulse lasers and also established a method to evaluate the bias on the polarization states, which is useful for a future variable–incident–angle collision system. In this paper, we present a result from the pilot search with the developed system and the method. The search result was consistent with null. We thus have set the upper limit on the minimum ALP-photon coupling down to

1.5 \times 10^{- 4}

GeV

^{- 1}

at the ALP mass of 1.53 eV with a confidence level of 95%. Full article

(This article belongs to the Special Issue Origins and Natures of Inflation, Dark Matter and Dark Energy)

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12 pages, 1755 KiB

Open AccessArticle

Sensitivity to Axion-like Particles with a Three-Beam Stimulated Resonant Photon Collider around the eV Mass Range

by Kensuke Homma, Fumiya Ishibashi, Yuri Kirita and Takumi Hasada

Universe 2023, 9(1), 20; https://doi.org/10.3390/universe9010020 - 29 Dec 2022

Cited by 5 | Viewed by 1199

Abstract

We propose a three-beam stimulated resonant photon collider with focused laser fields in order to directly produce an axion-like particle (ALP) with the two beams and to stimulate its decay by the remaining one. The expected sensitivity around the eV mass range has [...] Read more.

We propose a three-beam stimulated resonant photon collider with focused laser fields in order to directly produce an axion-like particle (ALP) with the two beams and to stimulate its decay by the remaining one. The expected sensitivity around the eV mass range has been evaluated. The result shows that the sensitivity can reach the ALP-photon coupling down to

O (10^{- 14})

GeV⁻¹ with 1 J class short-pulsed lasers. Full article

(This article belongs to the Special Issue Origins and Natures of Inflation, Dark Matter and Dark Energy)

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6 pages, 214 KiB

Open AccessArticle

Discretely Charged Dark Matter in Inflation Models Based on Holographic Space-Time

by Tom Banks and Willy Fischler

Universe 2022, 8(11), 600; https://doi.org/10.3390/universe8110600 - 14 Nov 2022

Cited by 5 | Viewed by 1167

Abstract

The holographic space-time (HST) model of inflation has a potential explanation for dark matter as tiny primordial black holes. Motivated by a recent paper of Barrau, we propose a version of this model where some of the inflationary black holes (IBHs), whose decay [...] Read more.

The holographic space-time (HST) model of inflation has a potential explanation for dark matter as tiny primordial black holes. Motivated by a recent paper of Barrau, we propose a version of this model where some of the inflationary black holes (IBHs), whose decay gives rise to the Hot Big Bang, carry the smallest value of a discrete symmetry charge. The fraction f of IBHs carrying this charge is difficult to estimate from first principles, but we determine it by requiring that the crossover between radiation and matter domination occurs at the correct temperature

T_{e q} \sim 1 eV = 10^{- 28} M_{P}

. The fraction is small,

f \sim 2 \times 10^{- 9}

, so we believe this gives an extremely plausible model of dark matter. Full article

(This article belongs to the Special Issue Origins and Natures of Inflation, Dark Matter and Dark Energy)

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14 pages, 469 KiB

Open AccessArticle

Nonlinear Charged Black Hole Solution in Rastall Gravity

by Gamal Gergess Lamee Nashed

Universe 2022, 8(10), 510; https://doi.org/10.3390/universe8100510 - 28 Sep 2022

Cited by 5 | Viewed by 1429

Abstract

We show that the spherically symmetric black hole (BH) solution of a charged (linear case) field equation of Rastall gravitational theory is not affected by the Rastall parameter and this is consistent with the results presented in the literature. However, when we apply [...] Read more.

We show that the spherically symmetric black hole (BH) solution of a charged (linear case) field equation of Rastall gravitational theory is not affected by the Rastall parameter and this is consistent with the results presented in the literature. However, when we apply the field equation of Rastall’s theory to a special form of nonlinear electrodynamics (NED) source, we derive a novel spherically symmetric BH solution that involves the Rastall parameter. The main source of the appearance of this parameter is the trace part of the NED source, which has a non-vanishing value, unlike the linear charged field equation. We show that the new BH solution is Anti−de-Sitter Reissner−Nordström spacetime in which the Rastall parameter is absorbed into the cosmological constant. This solution coincides with Reissner−Nordström solution in the GR limit, i.e., when Rastall’s parameter is vanishing. To gain more insight into this BH, we study the stability using the deviation of geodesic equations to derive the stability condition. Moreover, we explain the thermodynamic properties of this BH and show that it is stable, unlike the linear charged case that has a second-order phase transition. Finally, we prove the validity of the first law of thermodynamics. Full article

(This article belongs to the Special Issue Origins and Natures of Inflation, Dark Matter and Dark Energy)

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9 pages, 266 KiB

Open AccessArticle

Bianchi I Spacetimes in Chiral–Quintom Theory

by Andronikos Paliathanasis

Universe 2022, 8(10), 503; https://doi.org/10.3390/universe8100503 - 26 Sep 2022

Cited by 3 | Viewed by 1003

Abstract

In this paper, we study anisotropic exact solutions in the homogeneous Bianchi I background geometry in a multifield theory. Specifically, we consider the Chiral–Quintom theory, which is an extension of the Chiral theory, because at least one of the scalar fields can have [...] Read more.

In this paper, we study anisotropic exact solutions in the homogeneous Bianchi I background geometry in a multifield theory. Specifically, we consider the Chiral–Quintom theory, which is an extension of the Chiral theory, because at least one of the scalar fields can have negative energy density. Moreover, the Quintom theory can be recovered when one of the free parameters of the theory vanishes. We find that Kasner-like and anisotropic exponential solutions exist for specific functional forms of the scalar field potential. Finally, Noether symmetry analysis is applied for the classification of the theory according to the admitted symmetries. Conservation laws are determined, while we show that the Kasner-like solution is the analytic solution for the given model. Full article

(This article belongs to the Special Issue Origins and Natures of Inflation, Dark Matter and Dark Energy)

23 pages, 37045 KiB

Open AccessArticle

Multi-Modal Clustering Events Observed by Horizon-10T and Axion Quark Nuggets

by Ariel Zhitnitsky

Universe 2021, 7(10), 384; https://doi.org/10.3390/universe7100384 - 15 Oct 2021

Cited by 10 | Viewed by 1467

Abstract

The Horizon-10T collaboration have reported observation of Multi-Modal Events (MME) containing multiple peaks suggesting their clustering origin. These events are proven to be hard to explain in terms of conventional cosmic rays (CR). We propose that these MMEs might be result of the [...] Read more.

The Horizon-10T collaboration have reported observation of Multi-Modal Events (MME) containing multiple peaks suggesting their clustering origin. These events are proven to be hard to explain in terms of conventional cosmic rays (CR). We propose that these MMEs might be result of the dark matter annihilation events within the so-called axion quark nugget (AQN) dark matter model, which was originally invented for completely different purpose to explain the observed similarity between the dark and the visible components in the Universe, i.e.,

Ω_{DM} \sim Ω_{visible}

without any fitting parameters. We support this proposal by demonstrating that the observations, including the frequency of appearance, intensity, the spatial distribution, the time duration, the clustering features, and many other properties nicely match the emission characteristics of the AQN annihilation events in atmosphere. We list a number of features of the AQN events which are very distinct from conventional CR air showers. The observation (non-observation) of these features may substantiate (refute) our proposal. Full article

(This article belongs to the Special Issue Origins and Natures of Inflation, Dark Matter and Dark Energy)

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12 pages, 445 KiB

Open AccessArticle

Statefinder and O_m Diagnostics for New Generalized Chaplygin Gas Model

by Abdulla Al Mamon, Vipin Chandra Dubey and Kazuharu Bamba

Universe 2021, 7(10), 362; https://doi.org/10.3390/universe7100362 - 28 Sep 2021

Cited by 6 | Viewed by 1744

Abstract

We explore a unified model of dark matter and dark energy. This new model is a generalization of the generalized Chaplygin gas model and is known as a new generalized Chaplygin gas (NGCG) model. We study the evolutions of the Hubble parameter and [...] Read more.

We explore a unified model of dark matter and dark energy. This new model is a generalization of the generalized Chaplygin gas model and is known as a new generalized Chaplygin gas (NGCG) model. We study the evolutions of the Hubble parameter and the distance modulus for the model under consideration and the standard

Λ

CDM model and compare that with the observational datasets. Furthermore, we demonstrate two geometric diagnostics analyses including the statefinder

(r, s)

and

O_{m} (z)

to the discriminant NGCG model from the standard

Λ

CDM model. The trajectories of evolution for

(r, s)

and

O_{m} (z)

diagnostic planes are shown to understand the geometrical behavior of the NGCG model by using different observational data points. Full article

(This article belongs to the Special Issue Origins and Natures of Inflation, Dark Matter and Dark Energy)

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28 pages, 6156 KiB

Open AccessArticle

Results of Search for Magnetized Quark-Nugget Dark Matter from Radial Impacts on Earth

by J. Pace VanDevender, Robert G. Schmitt, Niall McGinley, David G. Duggan, Seamus McGinty, Aaron P. VanDevender, Peter Wilson, Deborah Dixon, Helen Girard and Jacquelyn McRae

Universe 2021, 7(5), 116; https://doi.org/10.3390/universe7050116 - 21 Apr 2021

Cited by 6 | Viewed by 1953

Abstract

Magnetized quark nuggets (MQNs) are a recently proposed dark-matter candidate consistent with the Standard Model and with Tatsumi’s theory of quark-nugget cores in magnetars. Previous publications have covered their formation in the early universe, aggregation into a broad mass distribution before they can [...] Read more.

Magnetized quark nuggets (MQNs) are a recently proposed dark-matter candidate consistent with the Standard Model and with Tatsumi’s theory of quark-nugget cores in magnetars. Previous publications have covered their formation in the early universe, aggregation into a broad mass distribution before they can decay by the weak force, interaction with normal matter through their magnetopause, and a first observation consistent MQNs: a nearly tangential impact limiting their surface-magnetic-field parameter B_o from Tatsumi’s ~10^12+/−1 T to 1.65 × 10¹² T +/− 21%. The MQN mass distribution and interaction cross section strongly depend on B_o. Their magnetopause is much larger than their geometric dimensions and can cause sufficient energy deposition to form non-meteorite craters, which are reported approximately annually. We report computer simulations of the MQN energy deposition in water-saturated peat, soft sediments, and granite, and report the results from excavating such a crater. Five points of agreement between observations and hydrodynamic simulations of an MQN impact support this second observation being consistent with MQN dark matter and suggest a method for qualifying additional MQN events. The results also redundantly constrain B_o to ≥ 4 × 10¹¹ T. Full article

(This article belongs to the Special Issue Origins and Natures of Inflation, Dark Matter and Dark Energy)

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30 pages, 7763 KiB

Open AccessArticle

Limits on Magnetized Quark-Nugget Dark Matter from Episodic Natural Events

by J. Pace VanDevender, Aaron P. VanDevender, Peter Wilson, Benjamin F. Hammel and Niall McGinley

Universe 2021, 7(2), 35; https://doi.org/10.3390/universe7020035 - 04 Feb 2021

Cited by 6 | Viewed by 2729

Abstract

A quark nugget is a hypothetical dark-matter candidate composed of approximately equal numbers of up, down, and strange quarks. Most models of quark nuggets do not include effects of their intrinsic magnetic field. However, Tatsumi used a mathematically tractable approximation of the Standard [...] Read more.

A quark nugget is a hypothetical dark-matter candidate composed of approximately equal numbers of up, down, and strange quarks. Most models of quark nuggets do not include effects of their intrinsic magnetic field. However, Tatsumi used a mathematically tractable approximation of the Standard Model of Particle Physics and found that the cores of magnetar pulsars may be quark nuggets in a ferromagnetic liquid state with surface magnetic field B_o = 10^12±1 T. We have applied that result to quark-nugget dark matter. Previous work addressed the formation and aggregation of magnetized quark nuggets (MQNs) into a broad and magnetically stabilized mass distribution before they could decay and addressed their interaction with normal matter through their magnetopause, losing translational velocity while gaining rotational velocity and radiating electromagnetic energy. The two orders of magnitude uncertainty in Tatsumi’s estimate for B_o precludes the practical design of systematic experiments to detect MQNs through their predicted interaction with matter. In this paper, we examine episodic events consistent with a unique signature of MQNs. If they are indeed caused by MQNs, they constrain the most likely values of B_o to 1.65 × 10¹² T +/− 21% and support the design of definitive tests of the MQN dark-matter hypothesis. Full article

(This article belongs to the Special Issue Origins and Natures of Inflation, Dark Matter and Dark Energy)

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Review

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90 pages, 11352 KiB

Open AccessReview

Observational Constraints on Dynamical Dark Energy Models

by Olga Avsajanishvili, Gennady Y. Chitov, Tina Kahniashvili, Sayan Mandal and Lado Samushia

Universe 2024, 10(3), 122; https://doi.org/10.3390/universe10030122 - 04 Mar 2024

Cited by 2 | Viewed by 908

Abstract

Scalar field

ϕ

CDM models provide an alternative to the standard

Λ

CDM paradigm, while being physically better motivated. Dynamical scalar field

ϕ

CDM models are divided into two classes: the quintessence (minimally and non-minimally interacting with gravity) and phantom models. These models [...] Read more.

Scalar field

ϕ

CDM models provide an alternative to the standard

Λ

CDM paradigm, while being physically better motivated. Dynamical scalar field

ϕ

CDM models are divided into two classes: the quintessence (minimally and non-minimally interacting with gravity) and phantom models. These models explain the phenomenology of late-time dark energy. In these models, energy density and pressure are time-dependent functions under the assumption that the scalar field is described by the ideal barotropic fluid model. As a consequence of this, the equation of state parameter of the

ϕ

CDM models is also a time-dependent function. The interaction between dark energy and dark matter, namely their transformation into each other, is considered in the interacting dark energy models. The evolution of the universe from the inflationary epoch to the present dark energy epoch is investigated in quintessential inflation models, in which a single scalar field plays a role of both the inflaton field at the inflationary epoch and of the quintessence scalar field at the present epoch. We start with an overview of the motivation behind these classes of models, the basic mathematical formalism, and the different classes of models. We then present a compilation of recent results of applying different observational probes to constraining

ϕ

CDM model parameters. Over the last two decades, the precision of observational data has increased immensely, leading to ever tighter constraints. A combination of the recent measurements favors the spatially flat

Λ

CDM model but a large class of

ϕ

CDM models is still not ruled out. Full article

(This article belongs to the Special Issue Origins and Natures of Inflation, Dark Matter and Dark Energy)

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