1. Dark energy and its connections to neutrino, baryo/leptogenesis and dark matter Xinmin Zhang Institute of High Energy Physics Beijing Outline of the talk I.Current status on determination of the equation of state of dark energy and Quintom Model II.Interacting dark energy and mass varying neutrino III. A unified model of dark energy, dark matter and baryogenesis IV. Searching for CPT violation with CMB V. Summary

2. Dark Energy: * Negative pressure:  * Smoothly distributed, (almost ) not clustering Candidates: * Cosmological constant (or vacuum Energy) cosmological constant problem! * Dynamical Field: Quintessence, K-essence, Phantom etc

3. 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: 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 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)

4. Feng, Wang & Zhang Astro-ph/0404224 Huterer & Cooray Astro-ph/0404062 z w

5. Implication in model building of dark energy 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: ( 精质 ) * Phantom: （幽灵） * K-essence: or but cannot across -1 A new scenario of Dark Energy : Quintom （精灵） (Zhang et al. Astro-ph/0404224) For ex: single scalar: multi-scalar:

6. Quintom Model building: Why challenges? No-Go Theorem: Equation of State W can not cross over w=-1 if the following conditions are satisfied: I.Einstein Gravity II.Minimal Coupling III.Single Scalar Field IV.Without higher derivative Examples of Quintom-like Models: 1. two scalar field 2. single scalar field with higher derivative 3. including vector field …… 4. Nonminimal Coupling …….. Vikman Phys. Rev. D 71, 023515 (2005) Gong-Bo Zhao et al. astro-ph/0507482 Bo Feng et al. astro-ph/0404224 ……. Hao Wei, PhD Thesis

7. Detailed study on: Two-field models of Quintom Dark Energy - Xiao-fei Zhang,Hong Li, Yunsong Piao and Xinmin Zhang I. Quintom model with two scalar fields: II. Quintom model with Phantom field and neutrino: Astro-ph/0501652

8. Quintom with Single scalar field and Higher Derivative For equivalent to two fields Mingzhe Li, Bo Feng, Xinmin Zhang, hep-ph/0503268

9. astro-ph/0407259, Steen Hannestad,Steen Hannestad Edvard Mortsell Adding CMB,LSS data

10. Include DE perturbation when parametrizing the EOS Seljak et al Astro-ph/0407372 Ch. Yeche et al Astro-ph/0507170 Neglect DE perturbations Including DE perturbation only when w>-1 BIASED!!

11. How to calculate the fluctuation of Dark Energy ?? Difficulty:

12. Perturbation of DE continuous never diverge! Zhao et.al PRD 72,123515 Dark Energy Perturbation in two-field Quintom model

13. Our strategy to handle perturbations when w crosses -1 for parametrized EOS I. Quintessence – like perturbation; II. Phantom – like perturbation; III.

14. Constrains on dark energy with SN Ia (Riess) + SDSS + WMAP-1 Observing dark energy dynamics with supernova, microwave background and galaxy clustering Jun-Qing Xia, Gong-Bo Zhao, Bo Feng, Hong Li and Xinmin Zhang Phys.Rev.D73, 063521, 2006

15. Jun-Qing Xia, Gongbo Zhao, Bo Feng, Hong Li and Xinmin Zhang Phys.Rev.D73, 063521, 2006 WMAP+SDSS+Riess WMAP+SDSS+SNLS Comparision of global fitting results with SN Ia (Riess) and SNLS

16. Constrain on dark energy by WMAP group (importance of perturbation)

21. Current constrains on dark energy 1.Cosmological constant fit the data well 2.Dynamical model are not ruled out 3.Quintom is mildly favored Short summary :

22. Features of Quintom ( “ 精灵 ” ) Dark Energy Model I.Challenges to Model building: A lot of recent studies on the models of Dark Energy with equation of state across -1 II.Dark energy perturbation well defined: Implications in CMB, LSS …… III.Different from cosmological constant, Quintessence and Phantom in the determination of the evolutions and the fate of the universe Oscillating Quintom

23. Oscillating Quintom and the Recurrent Universe: astro-ph/0407432 Bo Feng, Minzhe Li, Yunsong Piao, Xinmin Zhang

24. Parameterization: Astro-ph / 0605366

28. Bump-like dark energy

29. EoS with feature:

30. Probing this feature with GRB??

31. Precise Hubble diagram from SNe Ia From Dr. Xiao Feng Wang ’ s Hangzhou talk ( May, 2006) Precise Hubble diagram from SNe Ia From Dr. Xiao Feng Wang ’ s Hangzhou talk ( May, 2006)

32. Interacting Dark Energy Current data favors Quintom Quintom Dark Energy is described by dynamical scalar fields 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 * Interacting with DM (Peebles et al ) * Interacting with neutrinos ---Mass varying neutrinos * Derivatively couplings----Cosmological CPT violation  CMBPol

33. Xinmin Zhang etal. PRD68, 087301 (2003) Dark Energy and neutrinos ： Any connection between Dark Energy and neutrinos? 1.ΛCDM: 2.QCDM: If yes, very interesting: 2 of the biggest discoveries in the recent years Predictions : neutrino masses vary and cosmological CPT violation

34. Where, Corresponding the formula for the neutrino mass upper limit now is:

35. Astro-ph/0309800

36. New features of neutrino Dark Energy model: I.Unlike the ordinary matter the massive neutrino has equation of state II.Neutrino plays an important role in the evolution of the universe III.Mass varying neutrinos effects on CMB, LSS IV.Testing mass varying neutrinos with GRB V.Testing mass varying with neutrino oscillations

37. Cosmological evolution of Interacting Dark Energy models with mass varying neutrinos hep/ph/0412002 -Xiaojun Bi, Bo Feng, Hong Li, Xinmin Zhang

38. Astro-ph/0503349

39. Testing mass varying neutrino with short GRB -Hong Li, Zigao Dai, Xinmin Zhang: hep-ph/0411228

40. Neutrino oscillation probes of Dark Energy D.B. Kaplan et al., PRL 93,091801 (2003); V. Barger et al., hep-ph/0502196; M. Cirelli et al., hep-ph/0503028. Basic idea ： given by Neutrino oscillation Solar Neutrino oscillation ：

41. Derivative couplings:  A unified model of dark energy, dark matter and baryon matter 1)A unified model of baryogenesis and dark energy ----Quintessential baryo/leptogenesis 2)Probing CPT violation with WMAP and Boomerang 3)When SUSYing, Quintessino is dark matter particle ----A unified model of dark matter and dark energy

42. M.Li, X.Wang, B.Feng, X. Zhang PRD65,103511 (2002) M.Li & X. Zhang ， PLB573,20 (2003) In thermo equilibrium   Cosmological CPT violation  baryogenesis Quintessential Baryo(Lepto)genesis Cohen & Kaplan The value of depends on the model of Quintessence Cosmological CPT violation!

43. Searching for CPT violation

44. Cosmological CPT violation: predicting and Bo Feng, Mingzhe Li, Jun-Qing Xia, Xuelei Chen and Xinmin Zhang Phys. Rev. Lett. 96, 221302 (2006) (Note here the notation: G ~ E, C~ B)

45. Quintessino As Dark Matter If susying the Quintessence: Quintessence: Q; Squintessence: σ q ; Quintessino: Similar to : Axion, Saxion, Axino Majoron, Smajoron, Majorino If is lighter than, could serve as Dark matter Susying the following interaction (H: SU(2) doublet) gives * Prediction: long-lived charged particle: (R. Mohapatra and Zhang) (X. Bi, M. Li and Zhang) * Non-thermal production of Quintessino:

46. Summary I.Quintom Dark Energy Models: Current data consistent with the cosmological constant but mildly favor the Quintom: a dynamical dark energy with Equation of state evolving and crossing -1 need more data and model building of Quintom dark energy II. The massive neutrino might have connection with dark energy; open up a possibility of detecting dark energy non-gravitationally need more study III. Derivative couplings --  A unified model of dark energy, dark matter and baryogenesis: Quintessino as dark matter particle IV. Cosmological CPT Violation: Predicting and need more data

47. Thanks !