Planck Mass Rotons As Cold Dark Matter and Quintessence* F
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The Particle Zoo
219 8 The Particle Zoo 8.1 Introduction Around 1960 the situation in particle physics was very confusing. Elementary particlesa such as the photon, electron, muon and neutrino were known, but in addition many more particles were being discovered and almost any experiment added more to the list. The main property that these new particles had in common was that they were strongly interacting, meaning that they would interact strongly with protons and neutrons. In this they were different from photons, electrons, muons and neutrinos. A muon may actually traverse a nucleus without disturbing it, and a neutrino, being electrically neutral, may go through huge amounts of matter without any interaction. In other words, in some vague way these new particles seemed to belong to the same group of by Dr. Horst Wahl on 08/28/12. For personal use only. particles as the proton and neutron. In those days proton and neutron were mysterious as well, they seemed to be complicated compound states. At some point a classification scheme for all these particles including proton and neutron was introduced, and once that was done the situation clarified considerably. In that Facts And Mysteries In Elementary Particle Physics Downloaded from www.worldscientific.com era theoretical particle physics was dominated by Gell-Mann, who contributed enormously to that process of systematization and clarification. The result of this massive amount of experimental and theoretical work was the introduction of quarks, and the understanding that all those ‘new’ particles as well as the proton aWe call a particle elementary if we do not know of a further substructure. -
Absence of Landau Damping in Driven Three-Component Bose–Einstein
www.nature.com/scientificreports OPEN Absence of Landau damping in driven three-component Bose– Einstein condensate in optical Received: 19 June 2017 Accepted: 10 July 2018 lattices Published: xx xx xxxx Gavriil Shchedrin, Daniel Jaschke & Lincoln D. Carr We explore the quantum many-body physics of a three-component Bose-Einstein condensate in an optical lattice driven by laser felds in V and Λ confgurations. We obtain exact analytical expressions for the energy spectrum and amplitudes of elementary excitations, and discover symmetries among them. We demonstrate that the applied laser felds induce a gap in the otherwise gapless Bogoliubov spectrum. We fnd that Landau damping of the collective modes above the energy of the gap is carried by laser-induced roton modes and is considerably suppressed compared to the phonon-mediated damping endemic to undriven scalar condensates Multicomponent Bose-Einstein condensates (BECs) are a unique form of matter that allow one to explore coherent many-body phenomena in a macroscopic quantum system by manipulating its internal degrees of freedom1–3. Te ground state of alkali-based BECs, which includes 7Li, 23Na, and 87Rb, is characterized by the hyperfne spin F, that can be best probed in optical lattices, which liberate its 2F + 1 internal components and thus provides a direct access to its internal structure4–11. Driven three-component F = 1 BECs in V and Λ confgurations (see Fig. 1(b) and (c)) are totally distinct from two-component BECs3 due to the light interaction with three-level systems that results in the laser-induced coherence between excited states and ultimately leads to a number of fascinating physical phenomena, such as lasing without inversion (LWI)12,13, ultraslow light14,15, and quantum memory16. -
Physical Vacuum Is a Special Superfluid Medium
Physical vacuum is a special superfluid medium Valeriy I. Sbitnev∗ St. Petersburg B. P. Konstantinov Nuclear Physics Institute, NRC Kurchatov Institute, Gatchina, Leningrad district, 188350, Russia; Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, Berkeley, CA 94720, USA (Dated: August 9, 2016) The Navier-Stokes equation contains two terms which have been subjected to slight modification: (a) the viscosity term depends of time (the viscosity in average on time is zero, but its variance is non-zero); (b) the pressure gradient contains an added term describing the quantum entropy gradient multiplied by the pressure. Owing to these modifications, the Navier-Stokes equation can be reduced to the Schr¨odingerequation describing behavior of a particle into the vacuum being as a superfluid medium. Vortex structures arising in this medium show infinitely long life owing to zeroth average viscosity. The non-zero variance describes exchange of the vortex energy with zero-point energy of the vacuum. Radius of the vortex trembles around some average value. This observation sheds the light to the Zitterbewegung phenomenon. The long-lived vortex has a non-zero core where the vortex velocity vanishes. Keywords: Navier-Stokes; Schr¨odinger; zero-point fluctuations; superfluid vacuum; vortex; Bohmian trajectory; interference I. INTRODUCTION registered. Instead, the wave function represents it existence within an experimental scene [13]. A dramatic situation in physical understand- Another interpretation was proposed by Louis ing of the nature emerged in the late of 19th cen- de Broglie [18], which permits to explain such an tury. Observed phenomena on micro scales came experiment. In de Broglie's wave mechanics and into contradiction with the general positions of the double solution theory there are two waves. -
Dark Energy and Dark Matter in a Superfluid Universe Abstract
Dark Energy and Dark Matter in a Superfluid Universe1 Kerson Huang Massachusetts Institute of Technology, Cambridge, MA , USA 02139 and Institute of Advanced Studies, Nanyang Technological University, Singapore 639673 Abstract The vacuum is filled with complex scalar fields, such as the Higgs field. These fields serve as order parameters for superfluidity (quantum phase coherence over macroscopic distances), making the entire universe a superfluid. We review a mathematical model consisting of two aspects: (a) emergence of the superfluid during the big bang; (b) observable manifestations of superfluidity in the present universe. The creation aspect requires a self‐interacting scalar field that is asymptotically free, i.e., the interaction must grow from zero during the big bang, and this singles out the Halpern‐Huang potential, which has exponential behavior for large fields. It leads to an equivalent cosmological constant that decays like a power law, and this gives dark energy without "fine‐tuning". Quantum turbulence (chaotic vorticity) in the early universe was able to create all the matter in the universe, fulfilling the inflation scenario. In the present universe, the superfluid can be phenomenologically described by a nonlinear Klein‐Gordon equation. It predicts halos around galaxies with higher superfluid density, which is perceived as dark matter through gravitational lensing. In short, dark energy is the energy density of the cosmic superfluid, and dark matter arises from local fluctuations of the superfluid density 1 Invited talk at the Conference in Honor of 90th Birthday of Freeman Dyson, Institute of Advanced Studies, Nanyang Technological University, Singapore, 26‐29 August, 2013. 1 1. Overview Physics in the twentieth century was dominated by the theory of general relativity on the one hand, and quantum theory on the other. -
Study of Anisotropic Compact Stars with Quintessence Field And
Eur. Phys. J. C (2019) 79:919 https://doi.org/10.1140/epjc/s10052-019-7427-7 Regular Article - Theoretical Physics Study of anisotropic compact stars with quintessence field and modified chaplygin gas in f (T) gravity Pameli Sahaa, Ujjal Debnathb Department of Mathematics, Indian Institute of Engineering Science and Technology, Shibpur, Howrah 711 103, India Received: 18 May 2019 / Accepted: 25 October 2019 / Published online: 12 November 2019 © The Author(s) 2019 Abstract In this work, we get an idea of the existence of 1 Introduction compact stars in the background of f (T ) modified grav- ity where T is a scalar torsion. We acquire the equations Recently, compact stars, the most elemental objects of the of motion using anisotropic property within the spherically galaxies, acquire much attention to the researchers to study compact star with electromagnetic field, quintessence field their ages, structures and evolutions in cosmology as well as and modified Chaplygin gas in the framework of modi- astrophysics. After the stellar death, the residue portion is fied f (T ) gravity. Then by matching condition, we derive formed as compact stars which can be classified into white the unknown constants of our model to obtain many phys- dwarfs, neutron stars, strange stars and black holes. Com- ical quantities to give a sketch of its nature and also study pact star is very densed object i.e., posses massive mass and anisotropic behavior, energy conditions and stability. Finally, smaller radius as compared to the ordinary star. In astro- we estimate the numerical values of mass, surface redshift physics, the study of neutron star and the strange star moti- etc from our model to compare with the observational data vates the researchers to explore their features and structures for different types of compact stars. -
Quantum Vacuum Energy Density and Unifying Perspectives Between Gravity and Quantum Behaviour of Matter
Annales de la Fondation Louis de Broglie, Volume 42, numéro 2, 2017 251 Quantum vacuum energy density and unifying perspectives between gravity and quantum behaviour of matter Davide Fiscalettia, Amrit Sorlib aSpaceLife Institute, S. Lorenzo in Campo (PU), Italy corresponding author, email: [email protected] bSpaceLife Institute, S. Lorenzo in Campo (PU), Italy Foundations of Physics Institute, Idrija, Slovenia email: [email protected] ABSTRACT. A model of a three-dimensional quantum vacuum based on Planck energy density as a universal property of a granular space is suggested. This model introduces the possibility to interpret gravity and the quantum behaviour of matter as two different aspects of the same origin. The change of the quantum vacuum energy density can be considered as the fundamental medium which determines a bridge between gravity and the quantum behaviour, leading to new interest- ing perspectives about the problem of unifying gravity with quantum theory. PACS numbers: 04. ; 04.20-q ; 04.50.Kd ; 04.60.-m. Key words: general relativity, three-dimensional space, quantum vac- uum energy density, quantum mechanics, generalized Klein-Gordon equation for the quantum vacuum energy density, generalized Dirac equation for the quantum vacuum energy density. 1 Introduction The standard interpretation of phenomena in gravitational fields is in terms of a fundamentally curved space-time. However, this approach leads to well known problems if one aims to find a unifying picture which takes into account some basic aspects of the quantum theory. For this reason, several authors advocated different ways in order to treat gravitational interaction, in which the space-time manifold can be considered as an emergence of the deepest processes situated at the fundamental level of quantum gravity. -
Exploring the Stability and Dynamics of Dipolar Matter-Wave Dark Solitons
PHYSICAL REVIEW A 93, 063617 (2016) Exploring the stability and dynamics of dipolar matter-wave dark solitons M. J. Edmonds,1 T. Bland,1 D. H. J. O’Dell,2 and N. G. Parker1 1Joint Quantum Centre Durham–Newcastle, School of Mathematics and Statistics, Newcastle University, Newcastle upon Tyne, NE1 7RU, United Kingdom 2Department of Physics and Astronomy, McMaster University, Hamilton, Ontario, L8S 4M1, Canada (Received 4 March 2016; published 15 June 2016) We study the stability, form, and interaction of single and multiple dark solitons in quasi-one-dimensional dipolar Bose-Einstein condensates. The solitons are found numerically as stationary solutions in the moving frame of a nonlocal Gross Pitaevskii equation and characterized as a function of the key experimental parameters, namely the ratio of the dipolar atomic interactions to the van der Waals interactions, the polarization angle, and the condensate width. The solutions and their integrals of motion are strongly affected by the phonon and roton instabilities of the system. Dipolar matter-wave dark solitons propagate without dispersion and collide elastically away from these instabilities, with the dipolar interactions contributing an additional repulsion or attraction to the soliton-soliton interaction. However, close to the instabilities, the collisions are weakly dissipative. DOI: 10.1103/PhysRevA.93.063617 I. INTRODUCTION the atoms and their interactions using lasers as well as magnetic and electric fields. This, for example, has led to proposals to Solitary waves, or solitons, are excitations of nonlinear access exotic solitons such as in spin-orbit coupled conden- systems that possess both wavelike and particle-like qual- sates [21–23], chiral solitons in “interacting” gauge theories ities. -
Sounds of a Supersolid A
NEWS & VIEWS RESEARCH hypothesis came from extensive population humans, implying possible mosquito exposure long-distance spread of insecticide-resistant time-series analysis from that earlier study5, to malaria parasites and the potential to spread mosquitoes, worsening an already dire situ- which showed beyond reasonable doubt that infection over great distances. ation, given the current spread of insecticide a mosquito vector species called Anopheles However, the authors failed to detect resistance in mosquito populations. This would coluzzii persists locally in the dry season in parasite infections in their aerially sampled be a matter of great concern because insecticides as-yet-undiscovered places. However, the malaria vectors, a result that they assert is to be are the best means of malaria control currently data were not consistent with this outcome for expected given the small sample size and the low available8. However, long-distance migration other malaria vectors in the study area — the parasite-infection rates typical of populations of could facilitate the desirable spread of mosqui- species Anopheles gambiae and Anopheles ara- malaria vectors. A problem with this argument toes for gene-based methods of malaria-vector biensis — leaving wind-powered long-distance is that the typical infection rates they mention control. One thing is certain, Huestis and col- migration as the only remaining possibility to are based on one specific mosquito body part leagues have permanently transformed our explain the data5. (salivary glands), rather than the unknown but understanding of African malaria vectors and Both modelling6 and genetic studies7 undoubtedly much higher infection rates that what it will take to conquer malaria. -
New Physics, Dark Matter and Cosmology in the Light of Large Hadron Collider Ahmad Tarhini
New physics, Dark matter and cosmology in the light of Large Hadron Collider Ahmad Tarhini To cite this version: Ahmad Tarhini. New physics, Dark matter and cosmology in the light of Large Hadron Collider. High Energy Physics - Theory [hep-th]. Université Claude Bernard - Lyon I, 2013. English. tel-00847781 HAL Id: tel-00847781 https://tel.archives-ouvertes.fr/tel-00847781 Submitted on 24 Jul 2013 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. No d’ordre 108-2013 LYCEN – T 2013-08 Thèse présentée devant l’Université Claude Bernard Lyon 1 École Doctorale de Physique et d’Astrophysique pour l’obtention du DIPLÔME de DOCTORAT Spécialité : Physique Théorique / Physique des Particules (arrêté du 7 août 2006) par Ahmad TARHINI Nouvelle physique, Matière noire et cosmologie à l’aurore du Large Hadron Collider Soutenue le 5 Juillet 2013 devant la Commission d’Examen Jury : M. D. Tsimpis Président du jury M. U. Ellwanger Rapporteur M. G. Moreau Rapporteur Mme F. Mahmoudi Examinatrice M. G. Moultaka Examinateur M. A.S. Cornell Examinateur M. A. Deandrea Directeur de thèse M. A. Arbey Co-Directeur de thèse ii Order N ◦: 108-2013 Year 2013 PHD THESIS of the UNIVERSITY of LYON Delivered by the UNIVERSITY CLAUDE BERNARD LYON 1 Subject: Theoretical Physics / Particles Physics submitted by Mr. -
Lab Tests of Dark Energy Robert Caldwell Dartmouth College Dark Energy Accelerates the Universe
Lab Tests of Dark Energy Robert Caldwell Dartmouth College Dark Energy Accelerates the Universe Collaboration with Mike Romalis (Princeton), Deanne Dorak & Leo Motta (Dartmouth) “Possible laboratory search for a quintessence field,” MR+RC, arxiv:1302.1579 Dark Energy vs. The Higgs Higgs: Let there be mass m(φ)=gφ a/a¨ > 0 Quintessence: Accelerate It! Dynamical Field Clustering of Galaxies in SDSS-III / BOSS: Cosmological Implications, Sanchez et al 2012 Dynamical Field Planck 2013 Cosmological Parameters XVI Dark Energy Cosmic Scalar Field 1 = (∂φ)2 V (φ)+ + L −2 − Lsm Lint V (φ)=µ4(1 + cos(φ/f)) Cosmic PNGBs, Frieman, Hill and Watkins, PRD 46, 1226 (1992) “Quintessence and the rest of the world,” Carroll, PRL 81, 3067 (1998) Dark Energy Couplings to the Standard Model 1 = (∂φ)2 V (φ)+ + L −2 − Lsm Lint φ µν Photon-Quintessence = F F Lint −4M µν φ = E" B" ! M · “dark” interaction: quintessence does not see EM radiation Dark Energy Coupling to Electromagnetism Varying φ creates an anomalous charge density or current 1 ! E! ρ/# = ! φ B! ∇ · − 0 −Mc∇ · ∂E! 1 ! B! µ " µ J! = (φ˙B! + ! φ E! ) ∇× − 0 0 ∂t − 0 Mc3 ∇ × Magnetized bodies create an anomalous electric field Charged bodies create an anomalous magnetic field EM waves see novel permittivity / permeability Dark Energy Coupling to Electromagnetism Cosmic Solution: φ˙/Mc2 H ∼ φ/Mc2 Hv/c2 ∇ ∼ 42 !H 10− GeV ∼ • source terms are very weak • must be clever to see effect Dark Energy Coupling to Electromagnetism Cosmic Birefringence: 2 ˙ ∂ 2 φ wave equation µ ! B# B# = # B# 0 0 ∂t2 −∇ Mc∇× ˙ -
Strongly Interacting Bose-Einstein Condensates: Probes and Techniques
Strongly Interacting Bose-Einstein Condensates: Probes and Techniques by Juan Manuel Pino II B.S. Physics, University of Florida, 2002 A thesis submitted to the Faculty of the Graduate School of the University of Colorado in partial fulfillment of the requirements for the degree of Doctor of Philosophy Department of Physics 2010 This thesis entitled: Strongly Interacting Bose-Einstein Condensates: Probes and Techniques written by Juan Manuel Pino II has been approved for the Department of Physics Dr. Deborah S. Jin Dr. Eric A. Cornell Date The final copy of this thesis has been examined by the signatories, and we find that both the content and the form meet acceptable presentation standards of scholarly work in the above mentioned discipline. iii Pino II, Juan Manuel (Ph.D., Physics) Strongly Interacting Bose-Einstein Condensates: Probes and Techniques Thesis directed by Dr. Deborah S. Jin A dilute gas Bose-Einstein condensate (BEC) near a Feshbach resonance offers a system that can be tuned from the well-understood regime of weak interactions to the complex regime of strong interactions. Strong interactions play a central role in the phenomena of superfluidity in liquid He, and theoretical treatments for this regime have existed since the 1950's. However, these theories have not been experimentally tested as superfluid He offers no similar mechanism with which to tune the interactions. In dilute gas condensates near a Feshbach resonance, where interactions can be tuned, strong interactions have proven difficult to study due to the condensate's metastable nature with respect to the formation of weakly bound molecules. In this thesis, I introduce an experimental system and novel probes of the gas that have been specifically designed to study strongly interacting BECs. -
Dark Energy Theory Overview
Dark Energy Theory Overview Ed Copeland -- Nottingham University 1. Issues with pure Lambda 2. Models of Dark Energy 3. Modified Gravity approaches 4. Testing for and parameterising Dark Energy Dark Side of the Universe - Bergen - July 26th 2016 1 M. Betoule et al.: Joint cosmological analysis of the SNLS and SDSS SNe Ia. 46 The Universe is sample σcoh low-z 0.12 HST accelerating and C 44 SDSS-II 0.11 β yet we still really SNLS 0.08 − have little idea 1 42 HST 0.11 X what is causing ↵ SNLS σ Table 9. Values of coh used in the cosmological fits. Those val- + 40 this acceleration. ues correspond to the weighted mean per survey of the values ) G ( SDSS shown in Figure 7, except for HST sample for which we use the 38 Is it a average value of all samples. They do not depend on a specific M − cosmological B choice of cosmological model (see the discussion in §5.5). ? 36 m constant, an Low-z = 34 evolving scalar µ 0.2 field, evidence of modifications of 0.4 . General CDM 0 2 ⇤ 0.0 0.15 µ Relativity on . − 0 2 − large scales or µ 0.4 − 2 1 0 something yet to 10− 10− 10 coh 0.1 z be dreamt up ? σ Betoule et al 2014 2 Fig. 8. Top: Hubble diagram of the combined sample. The dis- tance modulus redshift relation of the best-fit ⇤CDM cosmol- 0.05 1 1 ogy for a fixed H0 = 70 km s− Mpc− is shown as the black line.