scholarly journals Axion/hidden-photon dark matter conversion into condensed matter axion

2021 ◽  
Vol 2021 (8) ◽  
Author(s):  
So Chigusa ◽  
Takeo Moroi ◽  
Kazunori Nakayama
Keyword(s):  
Elementary Particle ◽  
Dark Matter ◽  
Conversion Rate ◽  
Condensed Matter ◽  
The Other ◽  
Quantum Level ◽  
Wave Excitation ◽  
Spin Wave Excitation ◽  
The Relationship ◽  
The Universe

Abstract The QCD axion or axion-like particles are candidates of dark matter of the universe. On the other hand, axion-like excitations exist in certain condensed matter systems, which implies that there can be interactions of dark matter particles with condensed matter axions. We discuss the relationship between the condensed matter axion and a collective spin-wave excitation in an anti-ferromagnetic insulator at the quantum level. The conversion rate of the light dark matter, such as the elementary particle axion or hidden photon, into the condensed matter axion is estimated for the discovery of the dark matter signals.

TORUS KNOTS EMBODYING CURVATURE AND TORSION IN AN OTHERWISE FEATURELESS CONTINUUM

2011 ◽  
Vol 20 (12) ◽  
pp. 1723-1739 ◽  
Author(s):  
J. S. AVRIN
Keyword(s):  
Elementary Particle ◽  
General Relativity ◽  
Geometric Model ◽  
The Other ◽  
Particle Model ◽  
Torus Knots ◽  
Torus Knot ◽  
The Subject ◽  
Curvature And Torsion ◽  
The Relationship

The subject is a localized disturbance in the form of a torus knot of an otherwise featureless continuum. The knot's topologically quantized, self-sustaining nature emerges in an elementary, straightforward way on the basis of a simple geometric model, one that constrains the differential geometric basis it otherwise shares with General Relativity (GR). Two approaches are employed to generate the knot's solitonic nature, one emphasizing basic differential geometry and the other based on a Lagrangian. The relationship to GR is also examined, especially in terms of the formulation of an energy density for the Lagrangian. The emergent knot formalism is used to derive estimates of some measurable quantities for a certain elementary particle model documented in previous publications. Also emerging is the compatibility of the torus knot formalism and, by extension, that of the cited particle model, with general relativity as well as with the Dirac theoretic notion of antiparticles.

God′s Body: Epistemic and Ritual Conceptions from Sanskrit Texts of Logic

Paragrana ◽  
2009 ◽  
Vol 18 (1) ◽  
pp. 53-63
Author(s):  
Gérard Colas
Keyword(s):  
Image Of God ◽  
The Other ◽  
Religious Images ◽  
Natural Laws ◽  
Sacred Texts ◽  
Technical Requirements ◽  
Other Hand ◽  
The Relationship ◽  
The Image Of God ◽  
The Universe

AbstractDiscussions on the nature of the relationship between a god, his body and his material representation are almost non-existent in the Hindu devotional perspective, where such concerns are superfluous. Hindu theological and ritual Sanskrit texts, on the other hand, applied procedures of reasoning with regard to that relationship. This rationalization however accommodated rather than conflicted with the devotional attitude. Their attempt to clarify their stand vis-à-vis god′s body and material image followed from ideological or technical requirements. This was done sometimes systematically, as in the Viśiṣṭādvaita school of philosophy where the ritual image is declared to be “a divine descent (of God) for the purpose of worship”; sometimes incidentally, as in ritual manuals, where the process of changing statues into divine bodies is described.But why should gods have a body at all? While some contend that they do not possess any body, others assert that they possess several at the same time, yet others infer the necessity of a body for God to create the universe, to reveal sacred texts, etc. These are some arguments and counter-arguments found in theological texts. The nature of the hierarchy between divine descents and images (which may or may not be considered as real bodies of gods) is another aspect of the discussion.Another question is the various ways in which ritual texts consider the relation between a god and his image. While immediacy characterizes the relation between the devotee and the image of god, the relation between ritual and image is far from being spontaneous. Rituals insure the presence of a god in an image through a technico-mystical process consisting of successive stages and involving patrons, astrologers, artists, priests and others. The final product, namely a concrete god-cum-image, is fit for devotion, but remains for ever fragile, dependent on the continuity of rites and on the material preservation of the image. Behind the ritual perspective also lies the notion that this process of creating a body for a god is in keeping with “natural” laws. Hindu ritual prescriptions are applicable only to the religious images which, though man-made, are considered as “natural”. Supra-natural divine images, known as “self-manifested” images, must be worshiped, but are beyond the range of these prescriptions.

THE LINK BETWEEN GALAXIES AND DARK MATTER

2011 ◽  
Vol 20 (10) ◽  
pp. 1771-1777
Author(s):  
HOUJUN MO
Keyword(s):  
Dark Matter ◽  
Galaxy Formation ◽  
Luminosity Function ◽  
The Other ◽  
Dark Matter Halos ◽  
Galaxy Formation And Evolution ◽  
The Galaxy ◽  
Galaxy Halo ◽  
Formation And Evolution ◽  
The Universe

Given that dark matter is gravitationally dominant in the universe, and that galaxy formation is closely related to dark matter halos, a key first step in understanding galaxy formation and evolution in the CDM paradigm is to quantify the galaxy-halo connection for galaxies of different properties. Here I will present results about the halo/galaxy connection obtained from two different methods. One is based on the conditional luminosity function, which describes the occupation of galaxies in halos of different masses, and the other is based on galaxy systems properly selected to represent dark halos.

scholarly journals DILATONIC DARK MATTER — A NEW PARADIGM

1998 ◽  
Vol 13 (02) ◽  
pp. 109-117 ◽  
Author(s):  
Y. M. CHO ◽  
Y. Y. KEUM
Keyword(s):  
Dark Matter ◽  
Cold Dark Matter ◽  
The Other ◽  
New Paradigm ◽  
Excellent Candidate ◽  
The Universe

We study the possibility that the dilaton plays the role of the dark matter of the universe. We find that the condition for the dilaton to be the dark matter of the universe strongly restricts its mass to be around 0.5 keV or 270 MeV. For the other mass ranges, the dilaton either undercloses or overcloses the universe. The 0.5 keV dilaton has the free-streaming distance of about 1.4 Mpc and becomes and excellent candidate of a warm dark matter, while the 270 MeV one has the free-streaming distance of about 7.4 pc and becomes a cold dark matter. We discuss the possible ways to detect the dilaton experimentally.

scholarly journals GUT-constrained supersymmetry and dark matter in light of the new (g − 2)μ determination

2021 ◽  
Vol 2021 (5) ◽  
Author(s):  
Manimala Chakraborti ◽  
Leszek Roszkowski ◽  
Sebastian Trojanowski
Keyword(s):  
Dark Matter ◽  
Boundary Conditions ◽  
Phenomenological Models ◽  
Cross Section ◽  
Direct Detection ◽  
The Other ◽  
Total Density ◽  
Particle Spectra ◽  
Susy Models ◽  
The Universe

Abstract The recent confirmation by the Fermilab-based Muon g-2 experiment of the (g − 2)μ anomaly has important implications for allowed particle spectra in softly broken supersymmetry (SUSY) models with neutralino dark matter (DM). Generally, the DM has to be quite light, with the mass up to a few hundred GeV, and bino-dominated if it is to provide most of DM in the Universe. Otherwise, a higgsino or wino dominated DM is also allowed but only as a strongly subdominant component of at most a few percent of the total density. These general patterns can easily be found in the phenomenological models of SUSY but in GUT-constrained scenarios this proves much more challenging. In this paper we revisit the issue in the framework of some unified SUSY models with different GUT boundary conditions on the soft masses. We study the so-called non-universal gaugino model (NUGM) in which the mass of the gluino is disunified from those of the bino and the wino and an SO(10) and an SU(5) GUT-inspired models as examples. We find that in these unified frameworks the above two general patterns of DM can also be found, and thus the muon anomaly can also be accommodated, unlike in the simplest frameworks of the CMSSM or the NUHM. We show the resulting values of direct detection cross-section for points that do and do not satisfy the muon anomaly. On the other hand, it will be challenging to access those solutions at the LHC because the resulting spectra are generally very compressed.

scholarly journals Estimation of baryon asymmetry from dark matter decaying into IceCube neutrinos

2021 ◽  
pp. 2150078
Author(s):  
Tista Mukherjee ◽  
Madhurima Pandey ◽  
Debasish Majumdar ◽  
Ashadul Halder
Keyword(s):  
Dark Matter ◽  
Early Universe ◽  
Power Law ◽  
Lower Energy ◽  
High Energy ◽  
Baryon Asymmetry ◽  
The Other ◽  
Astrophysical Source ◽  
High Energy Neutrinos ◽  
The Universe

The recent results of IceCube Neutrino Observatory include an excess of PeV neutrino events which appear to follow a broken power-law different from the other lower energy neutrinos detected by IceCube. The possible astrophysical source of these neutrinos is still unknown. One possible source of such neutrinos could be the decay of nonthermal, long-lived heavy mass dark matter, whose mass should be [Formula: see text] GeV and could have produced at the very early Universe. They can undergo cascading decay via both hadronic and leptonic channels to finally produce such high energy neutrinos. This possibility has been explored in this work by studying the decay flux of these dark matter candidates. The mass and lifetime of such dark matter particles have been obtained by performing a [Formula: see text] fit with the PeV neutrino data of IceCube. We finally estimate the baryon asymmetry produced in the Universe due to such dark matter decay.

scholarly journals “Non vide mei di me chi vide il vero”: l’arte “verace” nel girone dei superbi come mise en abyme dell’arte dantesca nella Commedia

2021 ◽  
Vol 21 (1) ◽  
pp. 55-65
Author(s):  
Maria Maślanka-Soro
Keyword(s):  
Divine Comedy ◽  
The Other ◽  
Mise En Abyme ◽  
Other Hand ◽  
The Divine Comedy ◽  
The One ◽  
The Relationship ◽  
The Universe

“Non vide mei di me chi vide il vero”: L’art “verace” in the circle of proud as a mise en abyme of Dante’s art in the Comedy The purpose of this study is to discuss the problem of meta-poetic themes in the Divine Comedy, focusing in particular on the relationship between God’s art and Dante’s art in the context of the impression caused by the sight of the rock reliefs in the cornice of the proud in the Purgatorio, where the poet, presenting and imitating the art of God, in fact shows the mastery of his own art. The analysis leads to the conclusion that the examples of humility and pride carved on the walls and the rock path – the perfect work of God-the Artist, vibrant with life and called by Dante visibile parlare – are, on the one hand, a mise en abyme of its macroscopic version, which is the Universe created by him, and, on the other hand, a mise en abyme of the universe narrated with the simile perfection by Dante.

scholarly journals INDIRECT SEARCHES FOR DECAYING DARK MATTER

2013 ◽  
Vol 28 (27) ◽  
pp. 1330040 ◽  
Author(s):  
ALEJANDRO IBARRA ◽  
DAVID TRAN ◽  
CHRISTOPH WENIGER
Keyword(s):  
Elementary Particle ◽  
Dark Matter ◽  
Gamma Rays ◽  
Large Population ◽  
Electromagnetic Interactions ◽  
Decaying Dark Matter ◽  
History Of ◽  
Long Lifetime ◽  
Open Question ◽  
The Universe

Numerous observations point towards the existence of an unknown elementary particle with no electromagnetic interactions, a large population of which was presumably produced in the early stages of the history of the Universe. This so-called dark matter has survived until the present day, accounting for the 26% of the present energy budget of the Universe. It remains an open question whether the particles comprising the dark matter are absolutely stable or whether they have a finite but very long lifetime, which is a possibility since there is no known general principle guaranteeing perfect stability. In this paper, we review the observational limits on the lifetime of dark matter particles with mass in the GeV–TeV range using observations of the cosmic fluxes of antimatter, gamma-rays and neutrinos. We also examine some theoretically motivated scenarios that provide decaying dark matter candidates.

scholarly journals Modified Gravity and Dark Matter

2021 ◽  
Author(s):  
Syed Abbas ◽  
Nasim Akhtar ◽  
Danish Alam
Keyword(s):  
General Relativity ◽  
Dark Matter ◽  
Quantum Mechanics ◽  
Modified Gravity ◽  
Gravitational Force ◽  
Relativistic Quantum ◽  
The Other ◽  
Gravitational Mass ◽  
Galilei Group ◽  
The Universe

At present there is a renewed interest in theories of ”modified” gravity. Here, under a more drastic modification enforced by Galilei group, we obtain a completely new gravitational structure, and which exists in addition to the already available general relativity of today. Correlated with this, we show that in addition, there is a new ”modified” quantum mechanics, in as much as it exists as an independent and new ”pure” non-relativistic quantum me- chanics, and which has no relativistic counterpart. This is in addition to the present quantum mechanics, where the relativistic and non-relativistic structures are counterparts of each other. The above holds, firstly due to the correlation between Galilei group and quantum mechanics. These math- ematical conclusions are consolidated by the fact that there exists a physical Majorana interaction between each neutron- proton pairs in nuclei. Galilei invariance of Majorana exchange in Majorana interaction, shows that the mass here is of pure gravitational nature, and which is immune to the other three forces. This makes an amazing connection between the gravitational force and the quantum mechanics. This pure gravitational mass would man- ifest itself as dark matter of the universe. It is our new modified gravity that generates the dark matter.

scholarly journals SINGLET FERMION DARK MATTER AND ELECTROWEAK BARYOGENESIS WITH RADIATIVE NEUTRINO MASS

2008 ◽  
Vol 23 (12) ◽  
pp. 1813-1819 ◽  
Author(s):  
K. S. BABU ◽  
ERNEST MA
Keyword(s):  
Dark Matter ◽  
Scalar Field ◽  
Standard Model ◽  
Neutrino Mass ◽  
The Other ◽  
Higgs Potential ◽  
Neutral Component ◽  
The Standard Model ◽  
Realistic Possibility ◽  
The Universe

The model of radiative neutrino mass with dark matter proposed by one of us is extended to include a real singlet scalar field. There are then two important new consequences. One is the realistic possibility of having the lightest neutral singlet fermion (instead of the lightest neutral component of the dark scalar doublet) as the dark matter of the universe. The other is a modification of the effective Higgs potential of the Standard Model, consistent with electroweak baryogenesis.

Sign in / Sign up

Export Citation Format

Share Document