Transcript 暴涨宇宙学与暗能量
Interacting Dark Energy Xinmin Zhang Institute of High Energy Physics Beijing June 18, 2004 * Recent years Cosmology made big progress DE (73%) DM (23%) B (4%) * 4%: Particles in the standard model but why no antimatter? * Understanding the Dark Sector: Challenges to particle physics Dark Matter: Favored candidates: Axion Neutralino Thermal Production & Non-thermal Production For ex: consider a model with extra U (1) B-L U (1) broken B-L neutrino masses & cosmic string Jeannerot, String loop decay N R l h ~ ~ Brandenberger l h &Zhang, Jan. 1999 Thermal production Non-thermal 1， 2, enhancing the parameter space q q Weak interactions 3, cold dark matter q q q q “stronger” interactions warm dark matter CDM: “Nagging Problems” •Prediction of cuspy dark halos •Apparent prediction of too much substructures thermal Non-thermal • Astrophysical explanations Lin, Huang, Zhang & Brandenberger, • Particle physics PRL (2001) Dark Energy: * Negative pressure: / a a 4G ( 3 p) 3 3 p 0 w p / 1 / 3 * Smoothly distributed, (almost ) not clustering Candidates: * Cosmological constant (or vacuum Energy) 0 a T g 8G p w p / 1 ( 2 103 eV ) 4 8G m ~ 10-3 eV But: th / ob ~ 10120 , cosmological problem! * Dynamical Field: Quintessence, K-essence, Phantom etc L 1 2 V, p 1 Q 2 V Q Q V (Q ) Q 1 Q Q 2 2 2 1 wQ 1 Outline of this talk on Interacting DE •Very briefly review on the current constraints on Dark Energy (Feng, Wang and •A model of unifying DE (73%) and B (4%) Zhang) In the framework of Quintessence, introducing coupling: •A model of neutrinos with varying masses (Li, Feng Wang and Zhang) Since the scale of DE, Only comparable with mν, interesting to speculate on the possible connection betweens the two: Interaction between the neutrino and DE: (Gu, Wang and Zhang) •A model of DE and DM: SUSY fermionic partner of Quintessence,Quintessino as DM particle •Summary (Bi, Li and Zhang) Constraints on the Dark Energy A quantity characterizing the property of Dark Energy: Equation of state: w(Z)=P/ρ For example : * Vacuum Energy: w=-1 * Quintessence: * Phantom: Model independent analysis with the following parameterization： 1，w(z)=w_0 + w_1* z 2，w(z)=w_1 + w_a*z/(1+z) (E.Linder) Using the recent 157 Supernova data published by Riess et al. astro-ph/0402512) * Within 2 σ, the cosmological constant fits well the data * Data mildly favors a running of the W across -1 Feng, Wang & Zhang Astro-ph/0404224 Huterer & Cooray Astro-ph/0404062 If the running of w(Z), especially a transition across –1, confirmed in the future, big challenge to the model building * Vacuum : w=-1 * Quintessence: * Phantom: A new scenanio of Dark Energy : Quintom (Zhang et al.) For ex: single scalar: multi-scalar: Interacting Quintessence * If Quintessence –like scalar field responsible for the current acceleration of the Universe ,expected also to interact with the matter directly. Open new possibilities for the detection. * Direct coupling with ordinary matter Constraint from the limits on the long-range force * Interaction with derivative Goldstone theorem: Spin-dependent force a unified model of DE and Baryo(Lepto)genesis Quintessino as DM * Interacting with DM * Interacting with neutrinos: mass varying neutrino (Peebles et al ) Quintessential Baryogenesis M.Li, X.Wang, B.Feng, X. Zhang PRD65,103511 (2002); M.Li & X. Zhang， PLB573,20 (2003) Lint c Q M J B In thermo equilibrium Cohen & Kaplan 1/ 2 gb 2 2 1 1 nB b nb E ( E m ) dE [ 1 exp[( E ) / T ] 1 exp[( E b ) / T ] ] 2 m b 2 T 2 g bT 3 b b 3 g bQ [ O( ) ] c 6 T T 6M 2 2 s gT 3 45 The value of 15c g bQ nB / s 4 2 g MT depends on the model of Quintessence model：V (Q) f (Q) Exp[( / mpl )Q] Albrecht & Skordis Solution:Q PRL84,2076(2000) 4 3 1/ 2 10(2 4) g T2 Tracking T 0.01c M Decoupling T：B (TD ) H (TD ) (TD ) 0.01c TD 10 10 M If B-violation is due to electroweak sphalerons T about 100 GeV D requires Quintessential leptogenesis & neutrino mass limits Lint c Q M J B L Similarly: TD determined by L (TD ) H (TD ) which gives for degenerate neutrino masses: defining m i i Cosmological limits give WMAP: TD 2.5 10 GeV 11 SDSS: where and 12 10 GeV 1/ 2 2 2 m ( 0 . 2 eV ( ) ) i TD i (TD ) 0.01c TD 4.2 10 GeV 10 L TD 10 10 M T3 ~ 0.0 4 f 2 l LlL v2 m ~ f f Minimal model of Baryogenesis * In the Quintessence as Dark Energy scenario, this is the minimal model for Baryogenesis in the sense that no extra particle beyond the standard model is introduced . * In ΛCDM model, with f(R): function of Ricci scalar, I. If , Einstein equation give: so, in radiation dominant Universe, II. Davoudiasl,Kitano,Kribs Murayama and Steinhardt We propose , so generating n /s naturally! B H.Li, M.Li,X.Zhang Mass varying Neutrinos • Motivations: smaller than any scale in the particle Physics, however comparable with neutrino masses • Any connection between the two? Neutrino interacting with the Dark Energy • In the Quintessence-like models for Dark Energy: Possible couplings: Or in the see-saw model: Implication for Leptogenesis! Where, Corresponding the formula for the neutrino mass upper limit now is: Including the back reaction Bi,Feng,Li,and Zhang, in preparation R.Fordon, A.Nelson and N. Weiner consider a case with δ, c=0 R. D. Peccei hep-ph/0404277 Quintessino As Dark Matter •If susying the Quintessence: Quintessence: Q Squintessence: σ Quintessino: (X. Bi, M. Li and Zhang) q Similar to : Axion, Saxion, Axino Majoron, Smajoron, Majorino (R. Mohapatra and Zhang) •If is lighter than , could serve as Dark matter •Susying the following interaction (H: SU(2) doublet) gives gives * Prediction: long-lived charged particle: Summary • Dark Energy Interaction with I. for Baryo(Lepto)genesis II. neutrino: mass varying Implication in Leptogenesis (Bi, Gu, Wang and Zhang) Cosmological limits needs check III. SUSY: Quintessino as Dark matter • The Dynamics of the Dark sector might be very rich! ( remember that for the 4% sector, the dynamics is already very rich) Thanks !