1 Affleck-Dine Leptogenesis induced by the Flaton of Thermal Inflation Wan-il Park KAIST Korea Advanced Institute of Science and Technology Based on JHEP 0411:046,2004(hep-ph/ ) Summer Institute 2006: August 23-30, 2006 APTCP, Pohang, Korea

2 Contents  Introduction  Motivation  Model  Dynamics  Summary & Conclusion

3  Observed asymmetry  Matter-antimatter asymmetry - Is this given as initial condition of universe? Direct measurement (galaxy survey) Abundances of light elements (BBN) Density perturbation (CMBR) } Inflation  Dynamical generation of asymmetry is required after inflation: Baryogenesis !!! Introduction

4  Basic ingredients of baryogenesis (Sakharov, 1967) Baryon number violation C and CP-violation Departure from thermal equilibrium GUT baryogenesis, leptogenesis (Yoshimura, 1978; Fukugita and Yanagida, 1986) uses heavy particle decay → very high energy scale ~ GUT scale Electroweak baryogenesis (Kuzmin, Rubakov and Shaposhnikov, 1985) uses sphaleron, electroweak phase transition → around electroweak scale, minimal extension of SM Affleck-Dine(AD) baryogenesis (Affleck and Dine, 1985) uses MSSM-flat directions → intermediate scale, very simple and efficient  Several types of baryogenesis Introduction

5  Unwanted? Why? - Large enery density → “over closing” universe - Long life time with large number density → disturbing successful BBN, etc.  Properties * Primordial inflation can dilute sufficiently some heavy unwanted relics, - Small mass → thermal reproduction after reheating - Gravitationally suppressed weak coupling → late time decay or stable for example, monopoles  Unwanted relics produced after inflation (gravitino, moduli problem) Introduction  Gravitino problem (Khlopov and Linde, 1984; etc.)

6 * Initial abundance * Observational constraint ? Large entropy release is required > ~ < ~  Moduli problem Introduction (Coughlan, et. al., 1983; etc.)

7 Thermal Inflation due to thermal mass * Dilution factor: → Low scale → small number of e-folds inflation! Introduction * Thermal inflation (Lyth and Stewart, 1995)

8 Coherent oscillation of moduli field Electroweak baryogenesis Thermal Inflation Flaton decay 1. GUT baryogenesis & leptogenesis 2. Affleck-Dine baryogenesis New model ?  Incompatibility between thermal inflation and baryogenesis Motivation Too low temperature  no baryogenesis mechanism can work

9 -Working era: after thermal inflation to avoid dilution, before flaton decay to avoid too low energy scale - Efficiency: efficient from dilution by entropy release due to flaton decay => Proper base of new model = Affleck-Dine mechanism due to its efficiency  The required features for new model Motivation Angular momentum = charge asymmetry * Affleck-Dine mechanism - Setting initial condition: Hubble terms due to SUSY-breaking effect of finite energy of early universe

10  MSSM superpotential  Our superpotential Neutrino mass term Flaton self interaction term -term with  Superpotential, W Model (D. Jeong, K. Kadota, W. I. Park and E. D. Stewart, 2004)

11  Simplification : C onsideration of just single generation  Ansatz : Only and flaton have nonzero values  Potential : where Model  Ansatz & Potential

12  Key assumptions - All fields are held at origin initially due to thermal effect - rolls away first, then : is unstable near the end of thermal inflation - -: is unstable at the end of thermal inflation Dynamics

13 Dynamics 1a. rolls away 1b. Stabilizes 1c. Fixes initial phase of2a. rolls away 2b. becomes nonzero, → stabilizes dangerous directions 2c. Fixes phase of 3a. Brings back into origin 3b. Rotates the phase of 3c. Stabilizes

14 Dynamics

15  Way of resolution  Problem due to - Stability of our vacuum : τ > 1/H τ = the time scale for quantum tunnelling to the minima 1/H = the age of our universe - Avoiding being trapped : dynamical settling down in our vacuum  How about our model? - Stability of our vacuum : τ > 1/H in large enough parameter space (see “Kusenko, Langacker and Segre, 1996”) -Deeper non-MSSM minima do exist (see “Casas, Lleyda and Munoz, 1995”)  Potential problems Dynamics ? MSSM Non-MSSM

16 Gives negative mass squared to q Gives large mass to q  All the fields settle down in our vacuum!!!  deeper non-MSSM minimum exists with nonzero Give terms linear in where but - Avoiding being trapped: Dynamics

17  Simulation results (homogeneous mode) Dynamics of AD-fieldLepton number asymmetry Dynamics

18 Damping energy transfer from homogeneous modes to inhomogeneous modesPreheating: Thermal friction: decay when field passes near the origin  Preserving lepton asymmetry Dynamics

19 we expect { < ~ < ~ to Dynamics  Estimation of baryon asymmetry

20 Preliminary simulation result including preheating effect

21 Moduli Domination Thermal Inflation Flaton Domination Radiation Domination held at origin rolls away  ends thermal inflaton becomes nonzero  stabilizes dangerous directions decays held at origin brought back into origin with phase rotation  generation of L-asymmetry decays  partial reheating  EW symmetry restoration  L-asymmetry → B-asymmetry B-asymmetry diluted but survives radiation domination BBN held at origin reaches its VEV oscillates  Brief history of thermal inflation Summary & Conclusion rolls away

22  Baryogenesis compatible with thermal inflation was proposed.  Fairly minimal in the sense of particle physics theory.  Unique in the context of gravity mediated SUSY breaking and thermal inflation.  Flaton generated the -term and triggered the generation of lepton asymmetry.  Complete analysis of the damping of field is required as future work.  Our vacuum is unstable, but cosmological evolution leads to our vacuum.  can be tested at future particle accelerators.  Conclusions Summary & Conclusion