Interacting Dark Energy Xinmin Zhang Institute of High Energy Physics Beijing Outline of the talkI. Current constraints on Dark Energy a. Constraints from SN Ia b. Global analysis with WMAP, SDSS and SN Ia

II. Interacting Dark Energy and mass varying Neutrinos

III. Summary

Dark Energy:* Negative pressure:)3(

34/ pGaa

0a 3/1/ 03 pwp* Smoothly distributed, (almost ) not clusteringCandidates:* Cosmological constant (or vacuum Energy)

g

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12010~/ obth cosmological constant problem!

* Dynamical Field: Quintessence, K-essence, Phantom etc)(

21 QVQQL

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11 Qw

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)

Feng, Wang & Zhang

Astro-ph/0404224

Huterer & Cooray

Astro-ph/0404062

zw

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 scenanio of Dark Energy : Quintom （精灵） (Zhang et al. Astro-ph/0404224) For ex: single scalar:

multi-scalar:

astro-ph/0407259, Steen Hannestad, Edvard Mortsell

Adding CMB,LSS data

Include DE perturbation when Include DE perturbation when parametrizing the EOSparametrizing the EOS

Seljak et alAstro-ph/0407372

Ch. Yeche et alAstro-ph/0507170

Neglect DE perturbations

Including DE perturbation only when w>-1

BIASED!!

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

)1/(*1 zzwww 0

Jun-Qing Xia, Gongbo Zhao, Bo Feng, Hong Li and Xinmin Zhang Phys.Rev.D73, 063521, 2006

)1/(*1 zzwww 0

WMAP+SDSS+Riess WMAP+SDSS+SNLS

Comparision of global fitting results with SN Ia (Riess) and SNLS

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

Current constrains on dark energy1. Cosmological constant fit the data well2. Dynamical model are not ruled out3. Quintom is mildly favored

Short summary :

Features of Quintom ( “ 精灵 ” ) Dark Energy Model

I. A lot of recent studies on the models of Dark Energy with equation of state across -1

II. Implications in CMB:

III. Different from cosmological constant, Quintessence and Phantom in the determination of the evolutions and the fate of the universe

Oscillating Quintom

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

Parameterization: Astro-ph / 0605366

“Offline” analysis of the first 2 years

- Search the previous year - Search the previous year imaging data for likely imaging data for likely SNe either missed or SNe either missed or not spectred for various not spectred for various reasonsreasons

- get z from host galaxy - get z from host galaxy spectro (either by us or spectro (either by us or other projects) or get other projects) or get photo-z from imagingphoto-z from imaging

- photo-id the SN- photo-id the SN - add Ia to the Hubble - add Ia to the Hubble

diagram (in red)diagram (in red)

very preliminaryvery preliminary

Z=1.2 !Z=1.2 !

From Reynald Pain’s Hangzhou talk (May, 2006)

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

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

MllQ

RcR NNQ

mXinmin Zhang etal. PRD68, 087301 (2003)

Dark Energy and neutrinos：Any connection between Dark Energy and neutrinos?1. ΛCDM:2. QCDM:

443 )()10( mev

plQ M

meVm2

3310

If yes, very interesting: 2 of the biggest discoveries in the recent years Predictions : neutrino masses vary and cosmological CPT violation

Derivative couplings: Quintessential Leptogenesis -M. Li, X. Wang, B. Feng, X. Zhang Phys.Rev. D65 (2002) 103511

M.Li, X.Wang, B.Feng, X. Zhang PRD65,103511 (2002) M.Li & X. Zhang ， PLB573,20 (2003)

BJ

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intIn thermo equilibrium

Quintessential Baryo(Lepto)genesis

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Cohen & Kaplan

The value of depends on the model of QuintessenceCosmological CPT violation!

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

Astro-ph/0309800

New features of neutrino Dark Energy model:

I. Unlike the ordinary matter

the massive neutrino has equation of state

II. Neutrino plays an improtant 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

0w

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

Astro-ph/0503349

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

Neutrino oscillation probes of Dark Neutrino oscillation probes of Dark EnergyEnergy

D.B. Kaplan D.B. Kaplan et al.et al., PRL 93,09180, PRL 93,091801 (2003);1 (2003);V. Barger V. Barger et al.,et al., hep-ph/0502196; hep-ph/0502196;M. Cirelli M. Cirelli et al.et al., hep-ph/0503028., hep-ph/0503028.

Basic idea ： given by

)()()( ieff VV

)()( 0 Mmmeff

)(effV

Solar Neutrino oscillationNeutrino oscillation ：

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npei ,,,

Summary I. Quintom Dark Energy Models:

Current data consistant with the cosmological constant

but mildly favour 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

Thanks !Thanks !