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Luis A. Ureña-López Department of Physics, University of Guanajuato

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Luis A. Ureña-López Department of Physics, University of Guanajuato XXVIII REUNIÓN ANUAL XXVIII REUNIÓN ANUAL DE LA DIVISIÓN DE GRAVITACIÓN Y DE LA DIVISIÓN DE GRAVITACIÓN Y FÍSICA MATEMÁTICA Dark matterFÍSICA MATEMÁTICA with ultralightDE LA SOCIEDAD bosons MEXICANA DE andFÍSICA DE LA SOCIEDAD MEXICANA DE FÍSICA 5 y 6 de noviembre de 2020 its imprint 5 y 6 de noviembre on de 2020cosmological CINVESTAV, structure I.P.N. CINVESTAV, I.P.N. Luis A. Ureña-LópezEstimados Colegas: Department of Physics, University of Guanajuato, México Estimados Colegas: Tenemos el gusto de invitarlos a la reunión anual de nuestra división, que se llevará a cabo los días 5 y 6 de noviembre del presente año de manera virtual. La reunión anual tiene como obJetivo presentar trabaJos de investigación nacionales convocados por la Tenemos el gusto de invitarlos a la reunión anual de nuestra división, que se llevará a institución organizadora, en esta ocasión fue a cargo de CINVESTAV, I.P.N.. cabo los días 5 y 6 de noviembre del presente año de manera virtual. La reunión anual tiene como obJetivo presentar trabaJos de investigación nacionales convocados por la Durante la reunión el comité directivo convoca a una Mesa Redonda de discusión de institución organizadora, en esta ocasión fue a cargo de CINVESTAV, I.P.N.. A Rainbow of Dark Sectors,temas M arelacionadosrch 22 con -la AprilDGFM y una 2 Asamblea General, esta última tiene como obJetivo aprobar los informes y los proyectos de trabaJo de la Mesa Directiva (favor de Durante la reunión el comité directivo convoca a una Mesa Redonda de discusión revisarde los nuevos estatutos en la página de la división para su aprobación). temas relacionados con la DGFM y una Asamblea General, esta última tiene como obJetivo aprobar los informes y los proyectos de trabaJo de la Mesa Directiva (favorDebido de a la contingencia por COVID-19, la Reunión Anual se llevará a cabo de manera revisar los nuevos estatutos en la página de la división para su aprobación)1. virtual los días 5 y 6 de noviembre del presente año a través de la plataforma BlueJeans. Debido a la contingencia por COVID-19, la Reunión Anual se llevará a cabo de manera virtual los días 5 y 6 de noviembre del presente año a través de la plataforma BlueJeans. Non-relativistic! Nostalgia Cold and Fuzzy Dark Matter astro-ph/9910097 Wayne Hu, Rennan Barkana & Andrei Gruzinov Institute for Advanced Study, Princeton, NJ 08540 Revised February 1, 2008 A New Cosmological Model of Quintessence and Dark Matter Cold dark matter (CDM) models predict small-scale structureinexcessofobservationsofthecores Varun Sahni1,͑ and Limin Wang 2,† and abundance of dwarf galaxies. These problems might be solved, and the virtues of CDM models 1Inter-University Centre for Astronomy & Astrophysics, PostBag4,Pune411007,India retained, even without postulating ad hoc dark matter particle or field interactions, if the dark 2Department of Physics, 538 West 120th Street, Columbia University, New York NY 10027, USA ͑ matter is composed of ultra-light scalar particles (m ͑ 10 22eV), initially in a (cold) Bose-Einstein (February 1, 2008) condensate, similar to axion dark matter models. The wave properties of the dark matter stabilize We propose a new class of quintessence models in which late times oscillations of a scalar field give gravitational collapse providing halo cores and sharply suppressing small-scale linear power. rise to an e͑ective equation of state which can be negative andhencedrivetheobservedacceleration of the universe. Our ansatz provides a unified picture of quintessence and a new form of dark matter Introduction.— Recently, the small-scale shortcomings of the Compton wavelength m͑1 but much smallerwe than call Frustrated Cold Dark Matter (FCDM). FCDM inhibits gravitational clustering on small scales the otherwise widely successful cold dark matterastro-ph/0003365 (CDM) the particle horizon, one can employ a Newtonianand ap- could provide a natural resolution to the core density problem for disc galaxy halos. Since the models for structure formation have received much at- proximation to the gravitational interaction embeddedquintessence in field rolls towards a small value, constraints on slow-roll quintessence models are safely circumvented in our model. tention (see [1–4] and references therein). CDM models the covariant derivatives of the field equation and a non- Klein-Gordon equation PHYSICAL REVIEW D, VOLUME 63, 063506 predict cuspy dark matter halo profiles and an abundance relativistic approximation to the dispersion relation.PACS It is number(s): 04.62.+v, 98.80.Cq of low mass halos not seen in the rotation curves and lo- then convenient to define the wavefunction ͒ ⌽ Aei͑,out Further analysis of a cosmological model with quintessence and scalar dark matterThe recent discovery that type Ia high redshift super- to remain unchanged virtually from the Planck1 epoch μν ∂V cal population of dwarf galaxies respectively. Though the of the amplitude and phase of the field ͑ = A cos(mt͓⌽), 19 novae are fainter than they would be in an Einstein-de zpl 10 to z 2[5]resultinginanenormousdi͑er-∂ ( −gg ∂ ϕ) = significance of the discrepancies is still disputed and so- which obeys † μ ν Tonatiuh Matos* and L. Arturo Uren˜a-Lo´pez Sitter universe suggests that the universe mayastro-ph/0105564 be acceler- ence␭ in the scalar␭ field energy density and that of mat- Departamento de Fı´sica, Centro de Investigacio´n y de Estudios Avanzados del IPN, AP 14-740, 07000 Me´xico D.F., Mexico −g ∂ϕ lutions involving astrophysical processes in the baryonic ating, fuelled perhaps by a cosmological constant or some ter/radiation at early times. This leads to a fine tuning gas may still be possible͑Received (e.g. 1 [5]), June 2000; recent revised attention manuscript has received 5 October 2000; published3 a˙ 20 February1 2001͒2 i(͓t + )͒ =(͓ ␭ + mother͒)͒ , field possessing(2) long range ‘repulsive’ e͑ects [1,2]. problem: the relative values of ͒͑ and ͒m must be set We present the complete solution to a 95% scalar field cosmological model2 ina which the dark2m matter is ͒123 1 mostly focused on solutions involving the dark matter The acceleration of the universe is related toQuintessential the equation to Haloes very high around levels of Galaxies accuracy (͒͑/͒m)initial 10 in 2 2 modeled by a scalar field ⌽ with the scalar potential V(⌽)͑V0͓cosh(␭͑␬0⌽)͒1͔ and the dark energy is ␭ V(ϕ) = maϕ sector. where ͒ is the Newtonian gravitationalof state potential. of matter For through the Einstein equation order to ensure ͒͑/͒m 1atpreciselythepresentepoch. modeled by a scalar field ⌿, endowed with the scalar potential V˜ (⌿)͑V˜ ͓sinh(␣͑␬ ⌿)͔␤. This model has ␭ In the simplest modification, warm dark matter (m ͑ 0 0 Alexandre Arbeya,b ͑, JulienAmorereasonableassumptionmightbeiftheenergy Lesgourguesa and Pierre Salatia,b 2 only two free parameters, ␭ and the equation of state ␻ the. With unperturbed these potentials, thebackground, fine-tuning and the cosmic right hand side van- ⌿ 2a¨ 2 4͑G keV) replaces CDMcoincidence and suppresses problems are ameliorated small-scale for both struc- dark matterishes and dark and energy the and energy the model density agrees with in the astro- field, ␭ = m |͒=| /2, ͒c + ͒X (1 + 3wX ) (1) density in the ⌽-field were comparable to that of radiation a a)͑ Laboratoire3 de Physique Th´eorique LAPTH, B.P. 110, F-74941 Annecy-le-Vieux Cedex, France. (Fuzzy Dark Matter) ture by free-streamingnomical out observations. of potential For the wells scalar [3], dark but matter, this we clarify the meaning of a scalar Jeans length͑3 and then the at very early times – say at the end of inflation [6]. This redshifts like matter ␭ ␬ a . b) Universit´ede͑ Savoie, B.P. 1104,͒ F-73011 Chamb´eryCedex, France. modification may adverselymodel predicts a͑ aect suppression structure of the at mass somewhat power spectrum forOn small time scales scales having a short wave number comparedk⌽kmin,⌽ with, for cold the matter expansion͒c and X-matter with equation of state might even be expected if the ⌽-field were to be an in- where k ͑4.5h Mpc͒1 for ␭͑20.28. This last fact could help to explain the death of dwarf galaxies and larger scales. Small-scalemin,⌽ power could be suppressed time, the evolution equations become PX = w͒X .Clearlyanecessary(butnotsu͒cient) con- flationary relic, its energy set by an equipartition ansatz. the smoothness of galaxy core halos. From this, all parameters of the scalar dark matter potential are com- 11However September for 2001 the ⌽-field to remain subdominant until re- more cleanly in the initial fluctuations, perhaps originat- ͒23 dition for the universe to accelerate is wX < 1/3. In pletely determined. The dark matter consists of an ultralight particle, whose mass is m⌽͑1.1͓10 eV and other words the equation of state of X-matter͑ must vi- cently its energy density must decrease rapidly at early ing from a kink in theall the inflaton success of potential the standard [2], cold but dark its matter regen- model is recovered. This implies1 that2 a scalar field could also2 i͓t͒ =(͓ ␭ + m͒)͒ , ␭ ͒ =4␬G͔␭ . (3) times. Such behaviour clearly cannot arise for polynomial eration through non-linearbe a good candidate gravitational the dark matter collapse of the Universe. would 2m olate the strong energy conditionThe nature (SEC) of the so dark that matter͒X + that binds galaxies remains an open question. The favored p < likely still produce halo cusps [6]. 3PX < 0. Investigationscandidate of cosmological has been so models far the neutralino. with potentials This massiveV speci(⌽)es with⌽ , evanescent0 <p interactionsfew,forwhich is now ͒͑ will ␭ ͓ DOI: 10.1103/PhysRevD.63.063506Assuming PACS the number dark͑s͒ matter: 98.80.Cq, also 95.35. dominatesd ⌽m + ⌽X the energy1havedemonstratedthatthesemodelsout-in di͑culty. It would actually collapse inrapidly dense clumps dominate and w theould total therefore density␭ play havocresulting with in the a colossal More radical suggestions include strong self- 2 2 ͒ matter it is supposed to shepherd.
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