The Equation of State and the Sphaleron Rate in the Standard Model

The Equation of State and the Sphaleron Rate in the Standard Model

The equation of state and the sphaleron rate in the Standard Model Kari Rummukainen University of Helsinki and Helsinki Institute of Physics D'Onofrio, Rummukainen, Tranberg arXiv:1404.3565 D'Onofrio, Rummukainen, arXiv:1508.07161 Big Bang and the little bangs, CERN 8/2016 K. Rummukainen (Helsinki) SM equation of state 1 / 25 The \Bump" The \bump" has ceased to be (. or is it just resting?) the Standard Model rules (still) K. Rummukainen (Helsinki) SM equation of state 2 / 25 Phase transitions in the Standard Model No phase transitions in the Standard Model (at µ = 0) I QCD and EW \phase transitions" are cross-overs Many BSM models have a first order EW phase transition 7! I EW baryogenesis (Kainulainen) I Gravitational waves (Weir) K. Rummukainen (Helsinki) SM equation of state 3 / 25 In this talk: Precision results of EW: I Pseudocritical temperature I Equation of state - \softness", width of the cross-over I Sphaleron rate Why study these? I it's the Standard. I Background to cosmological applications, e.g. leptogenesis I Precision properties of physics K. Rummukainen (Helsinki) SM equation of state 4 / 25 Phase diagram of the electroweak SM After lots of activity on and off the lattice: > ! No phase transition at all, smooth \cross-over" for mHiggs∼72 GeV 130 symmetric phase 120 [Kajantie,Laine,K.R.,Shaposhnikov,Tsypin 95{98] 110 2nd order endpoint /GeV c T 100 see also 1st order transition [Csikor,Fodor, Heitger] 90 [G¨urtler,Ilgenfritz,Schiller,Strecha] broken Higgs phase 80 50 60 70 80 90 mH/GeV K. Rummukainen (Helsinki) SM equation of state 5 / 25 Overall EOS [Laine, Schr¨oder2006] 0.4 12 10 0.3 8 4 6 p / T w m = 150 GeV 0.2 2 4 H c m = 200 GeV s H 1/3 2 0.1 0 1 2 3 4 5 6 1 2 3 4 5 6 10 10 10 10 10 10 10 10 10 10 10 10 T / MeV T / MeV Perturbation theory + Lattice QCD + Hadron RG Here EW transition featureless K. Rummukainen (Helsinki) SM equation of state 6 / 25 Equation of state and the pseudocritical temperature K. Rummukainen (Helsinki) SM equation of state 7 / 25 3d effective theory Tool for perturbative and lattice computations Modes p > g 2T are perturbative (at weak coupling): can be integrated out in stages: 1. p>∼T : fermions, non-zero Matsubara frequencies ! 3d theory (dimensional reduction) 1/ T 2. Electric modes p ∼ gT 2 Obtain a \magnetic theory" for modes p<∼g T . Fully contains the non-perturbative thermal physics. K. Rummukainen (Helsinki) SM equation of state 8 / 25 3d effective theory Physics at T = 0 4D SM action: - Fix physics perturbatively £ (αS (MW ), GF , MH , MW , MZ , Mtop) £ £ £ Integration over scales T and gT (at 2{loop level) £ £ £ 3D continuum effective theory 2{loop countertermsB B in lattice perturbation theory BN 3D lattice theory K. Rummukainen (Helsinki) SM equation of state 9 / 25 0.394 3d effective Lagrangian: 0.3935 /T 2 3 0.393 g 1 1 0.3925 L = F aF a + B B + 0.3 4 ij ij 4 ij ij 0 y 2 y y 2 (Di φ) Di φ + m3φ φ + λ3(φ φ) y -0.3 -0.6 SU(2) + U(1) gauge + Higgs 0.295 Parameters: x 0.29 2 2 0.285 g3 ∼ gW T 2 0.3105 x ≡ λ3=g3 2 4 z 0.31 y ≡ m3=g3 02 2 0.3095 z ≡ g3 =g3 140 150 160 170 T/GeV K. Rummukainen (Helsinki) SM equation of state 10 / 25 Calculating the EOS Developed by Laine and Meyer 2015 Higgs mass parameter ν and T are the only dimensionful parameters For dimensional reasons: p(T ) p µ¯ ν2(¯µ) p (¯µ, ν2(¯µ); g 2(¯µ)) = R ; ; g 2(¯µ) − 0R T 4 T 4 T T 2 T 4 µ¯: MS scale, p0R: zero-temperature pressure g 2(¯µ): all dimensionless couplings in the SM Interaction measure: d p(T ) ∆ = T dT T 4 @(p =T 4) 2ν2[Z hφyφi ] 4p = − R − m 4d R + 0R @ ln(¯µ/T ) T 4 T 4 ≡ ∆1 + ∆2 + ∆3 hφyφi Applying 3d effective theory:∆ = ∆A + ∆B 3D 2 2 2 T K. Rummukainen (Helsinki) SM equation of state 11 / 25 Calculating the EOS y A B hφ φi3D Thus, ∆ = ∆1 + ∆3 + ∆2 + δ2 T 6 All ∆i 's computed perturbatively, uncertainty O(g ) [Laine, Meyer] y On the other hand, hφ φi3D can be perturbatively computed in the symmetric phase and in the broken phase 2 4 Expansions fail near m =g3 ≡ y ∼ 0 { i.e. just at the cross-over ) Non-perturbative evaluation of hφyφi needed ) Lattice simulations Using thermodynamic identities, other quantities can be obtained: p, e, heat capacity CV , speed of sound cs ... Laine and Meyer did the analysis, but using poor quality lattice data (provided by me et al.). ) Revisit with new simulations K. Rummukainen (Helsinki) SM equation of state 12 / 25 Higgs field expectation value 0.6 Red dots: 3D lattice 0.5 (continuum limit) Green bands: 0.4 I Broken phase: 2-loop Coleman-Weinberg [Kajantie et 0.3 >/T φ + al 95] φ < I Symmetric phase: 3-loop 0.2 [Laine and Meyer 2015] Agreement remarkably good 0.1 away from the cross-over P.T. does not converge near the 0 cross-over 140 145 150 155 160 165 170 T/GeV K. Rummukainen (Helsinki) SM equation of state 13 / 25 Higgs susceptibility & pseudocritical temperature 10 β=6 8 β=9 β=16 φ 6 + Define pseudocritical T : maximum φ χ location of the hφyφi susceptibility 4 χφyφ: 2 Tc = 159:6 ± 0:1 ± 1:5 GeV 0 140 145 150 155 160 165 170 1st error: lattice errors T/GeV 2nd error: estimate of the 10 systematic uncertainty in 3d action 8 φ + φ χ 6 Right: continuum extrapolation of χ 4 2 156 157 158 159 160 161 162 T/GeV K. Rummukainen (Helsinki) SM equation of state 14 / 25 Interaction measure 0.7 Convert hφyφi to interaction measure ∆ = ( − 3p)=T 4 4 Band: lattice errors + variation 0.65 µ¯ = (0:5 ::: 2)πT . - 3p)/T ε ( Non-trivial feature between broken phase (low T ) and symmetric phase 0.6 (high T ) behaviour Width of the cross-over region ∼ 2 ::: 3 GeV 140 145 150 155 160 165 170 T/GeV K. Rummukainen (Helsinki) SM equation of state 15 / 25 Pressure and energy density 34.6 Pressure: 4 34.4 e/T Z T 0 p(T ) p(T0) 0 ∆(T ) 4 − 4 = dT 0 1% T T T 34.2 0 T0 4 Use reference temperature , 3p/T 4 34 T0 = 140 GeV, e/T 4 pert. pressure p(T0)=T0 = 11:173 33.8 [Laine, Schr¨oder2006] 4 3p/T Energy density e = ∆ + 3p 33.6 p(T0) has ∼ 1% uncertainty ! 140 145 150 155 160 165 170 uncertainty for e and p T/GeV K. Rummukainen (Helsinki) SM equation of state 16 / 25 More thermodynamics 0.334 142 1/3 0.332 141 0.33 140 2 3 c s /T V 0.328 C 139 0.326 w 138 0.324 137 140 145 150 155 160 165 170 140 145 150 155 160 165 170 T/GeV T/GeV 0 Heat capacity CV = e (T ) 2 0 0 Speed of sound: cs = p =e EOS parameter w = p=e Cross-over well defined, but very soft! K. Rummukainen (Helsinki) SM equation of state 17 / 25 Masses 3 2 Higgs and W screening masses Effective cos θWeinberg 0,8 1.1 m =9 H βG m =16 H βG m 3 β =9 0,6 W G 1 m 3 =16 W βG 0,4 γ 0.9 A m/T 0,2 0.8 cos2 θW 0 0.7 140 145 150 155 160 165 170 140 145 150 155 160 165 170 T/GeV T/GeV K. Rummukainen (Helsinki) SM equation of state 18 / 25 Sphaleron rate K. Rummukainen (Helsinki) SM equation of state 19 / 25 Background Anomaly: baryon number B and gauge topology are connected: Z t Z 3 µν ~ ∆B = ∆L = 3∆NCS = 2 dt dVF Fµν 32π 0 Baryogenesis Rate in thermal equilibrium: h(∆N (t))2i Γ = lim CS V ;t!1 Vt 5 4 In the symmetric phase, Γ / αW T [Arnold, Son, Yaffe 97] 5 4 or rather Γ / αW log(1/αW )T [B¨odeker 98] In the broken phase the rate is exponentially suppressed Turning off of the rate is important for some baryogenesis scenarios K. Rummukainen (Helsinki) SM equation of state 20 / 25 Calculation of the sphaleron rate Non-perturbative ) real-time lattice simulations Several methods: Classical EOM [Ambjorn, Krasnitz 95; + many] I UV modes (HTL) make result lattice spacing depednent [Arnold 97] Classical + HTL effective theories [Moore, Hu, Muller 97; Bodeker, Moore, K.R 99] I More control over UV modes, no continuum limit I Used also in studies of plasma instabilities in HIC B¨odeker method: [B¨odeker 98], heat bath version [Moore 98] 2 I Fully dissipative evolution of soft (g T ) modes X Exact to leading log order log(1=g 2), 9 continuum limit, very simple to use I Same \action" and cont. limit as in 3D thermo simulation 9 lot of lattice results in pure gauge, few in broken EW phase. Here: physical Higgs mass K. Rummukainen (Helsinki) SM equation of state 21 / 25 Evolution of NCS Symmetric T = 152GeV, broken T = 145GeV, deeply broken T = 140GeV (with mH = 113GeV) [D'Onofrio et al 12] 12 1 60 10 0.8 8 0.6 CS CS CS 40 0.4 6 0.2 0 4 20 -0.2 2 -0.4 Chern-Simons number N Chern-Simons number N Chern-Simons number N -0.6 0 0 -0.8 -2 -1 -20 5 5 5 5 5 0.0 5.0×104 1.0×105 1.5×105 2.0×105 0 1×10 2×10 3×10 4×10 5×10 0 1×105 2×105 3×105 4×105 5×105 Measurements Measurements Measurements 1 0 10 1.4 1.2 0.8 -1 10 1 0.6 0.8 -2 10 0.6 0.4 Normalized distribution Normalized distribution 0.4 normalized distribution (log) -3 10 0.2 0.2 -4 0 0 10 0 0.2 0.4 0.6 0.8 1 0 0.2 0.4 0.6 0.8 1 0 0.2 0.4 0.6 0.8 1 Chern-Simons number N Chern-Simons number N CS CS Chern-Simons number NCS K.

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