Planck results (1 st release)

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2 General Introduction Planck results (1 st release) From Planck Collaboration.XVI Standard cosmological model in good agreement with data but Valentina Salvatelli Interacting Dark Energy in light of Planck results 2/14

3 General Introduction Hubble constant tension some tensions exist! Hubble Constant value From Planck Collaboration.XVI arxiv: Measurement from Planck (assuming standard cosmology) H 0 = 67.3 ± 1.2 km/s/mpc Local measurement from Hubble Space Telescope Riess et al Freedman et al H 0 = 73.8 ± 2.4km/s/Mpc AN HINT FOR NEW PHYSICS??? Valentina Salvatelli Interacting Dark Energy in light of Planck results 3/14

4 Interacting Dark Energy Parametrization Dark matter-dark energy interacting models Models where we allow an energy-momentum transfer between fluids r µ T µ (dm) = Q r µ T µ (de) = Q Tantalizing scenario to investigate! ALLOWED BY OBSERVATIONS (only the interaction with ordinary matter is strongly constrained) CAN ALLEVIATE THE COINCIDENCE PROBLEM POSSIBLE EXPLANATION TO THE TENSION BETWEEN LOCAL AND HIGH-REDSHIFT MEASUREMENTS OF THE HUBBLE CONSTANT Valentina Salvatelli Interacting Dark Energy in light of Planck results 4/14

5 Interacting Dark Energy Parametrization Energy Momentum Transfer frame 2 alternatives frames to define the energy-momentum exchange DEvel DMvel 4- velocity Q = Qu (de) /a Q = Qu (dm) /a No momentum transfer to the DE frame Change in DM peculiar velocity Fifth force effect à Effectively modified gravity models Interac5on rate No momentum transfer to DM frame No violation of the weak equivalence principle Scale factor Valentina Salvatelli Interacting Dark Energy in light of Planck results 5/14

6 Interacting Dark Energy Parametrization Background evolution ( in a flat universe ) Modified background equa5ons dm +3H dm = Q de +3H de (1 + w) = Q H =ȧ/a The background evolution does not depend on the frame If Q<0 DM passes energy to DE, that implies 0 dm Q<0 < 0 dm Q=0 Effec5ve equa5ons of state w e dm = Q 3H dm w e de = w + Coupling imitates dynamical dark energy even if w is constant Q<0 yields to more negative effective w Q<0 acts as a positive pressure in the dark matter EoS Q 3H de Valentina Salvatelli Interacting Dark Energy in light of Planck results 6/14

7 Interacting Dark Energy Parametrization Linear Perturbation theory ( Newtonian gauge ) i v i Baryons not coupled equations do not change dm = ( dm 3 ) + Q Q dm Q dm + dm = H dm + k 2 +(1 b) Q dm ( de dm ) h de = (1 + w)( de 3 ) 3H i ĉ 2 s de w de + H 3(1 + w)+ Q de de k 2 de = H 1 3ĉ 2 s de ĉ 2 s de +b 1+w Q de Q Q de + Q H de de + k2 1+w ĉ2 s de de + k 2 b Q de dm 1+w b =0 if Q / u (de) b =1 if Q / u (dm) Euler equa5on only changes in DEvel models) 7 Valentina Salvatelli Interacting Dark Energy in light of Planck results 7/14

8 Interacting Dark Energy Parametrization A model to be tested DMvel frame Q = H de u dm Dimensionless coupling parameter MODEL PROS : M.B.Gavela et al. JCAP 0907:034,2009 Viable scenario No instabilities (if Q<0 and w>-1) Analytic form of H(z) Changes in background and growth evolution ( dm (z) not / (1 + z) 3 ) Credits to Laura Lopez- Honorez Valentina Salvatelli Interacting Interacting Dark Energy Dark and Energy Modified in light Gravity of Planck in light results of Planck results 10/27 8/14

9 Interacting Dark Energy Constraints Effects on the TT power spectrum Decreased amplitude of the spectrum Peaks shifted towards lower multipoles CDM =-0.2 = l(l+1)c l TT /2 [µk 2 ] Multipole-l 9 Valentina Salvatelli Interacting Interacting Dark Energy Dark and Energy Modified in light Gravity of Planck in light results of Planck results 11/27 9/14

10 Interacting Dark Energy Constraints PLANCK Constraints VS, A. Marchini, L.Lopez- Honorez, O.Mena, Phys. Rev. D 88, (2014) astro- ph/ c h A L =1 w = N eff =3.046 P m =0.06 ev An interacting scenario is compatible with data and not disfavoured The degeneracy between H 0 and ξ favours larger values for H 0, the tension with HST is solved m H 0 Valentina Salvatelli Interacting Dark Energy in light of Planck results 10/14

11 Interacting Dark Energy Constraints PLANCK+HST constraints VS, A. Marchini, L.Lopez- Honorez, O.Mena, Phys. Rev. D 88, (2014) astro- ph/ Hubble Space Telescope prior H 0 = 73.8 ± 2.4km/s/Mpc c h If we include the HST prior a zero coupling is excluded at 95% c.l. m H 0 11 Valentina Salvatelli Interacting Dark Energy in light of Planck results 11/14

12 Interacting Dark Energy Constraints PLANCK+BAO constraints VS, A. Marchini, L.Lopez- Honorez, O.Mena, Phys. Rev. D 88, (2014) astro- ph/ BAO measurements from 6DF, SDSS,BOSS surveys c h If we include BAO a zero coupling is excluded at 68% c.l and the H0 tension is alleviated m H 0 12 Valentina Salvatelli Interacting Dark Energy in light of Planck results 12/14

13 Interacting Dark Energy Constraints Is the H0 tension an evidence for coupling? e tension between the Hubble constant value measured by the Hubble Space Telescope and measured by PLANCK is solved in this dark coupled scenario. 13 Valentina Salvatelli Interacting Dark Energy in light of Planck results 13/14

14 Conclusions To summarize For the interacting dark energy scenario that we have investigated we can conclude that : it is compatible with PLANCK and with PLANCK combined with low redshift measurements it can solve the tension between PLANCK and HST measurements of the Hubble constant value a null interaction is excluded at 95% c.l. if we consider the combined constraint from PLANCK+HST Valentina Salvatelli Interacting Dark Energy in light of Planck results 14/14

15 Valentina Salvatelli Interacting Dark Energy in light of Planck results 15

16 Backup Coupling Constraints varying w VS, A. Marchini, L.Lopez- Honorez, O.Mena, Phys. Rev. D 88, (2014) astro- ph/ PLANCK c h m H 0 PLANCK +HST PLANCK +BAO Valentina Salvatelli Interacting Dark Energy and Modified Gravity in light of Planck results

17 Backup Coupling Posterior distributions Valentina Salvatelli Interacting Dark Energy and Modified Gravity in light of Planck results

18 Backup Evolution of energy densities in interacting scenarios Credits to Laura Lopez- Honorez Fine tuning problem is worsened in this case CMB is sensitive to densities at recombination Valentina Salvatelli Interacting Dark Energy and Modified Gravity in light of Planck results

19 Backup Further indication from Supernovae Combined constraints from CMB and Supernovae PLANCK+WP+SNLS w = % c.l. Reconstructed dark energy equation of state if the real universe is coupled and we use standard equations Valentina Salvatelli Interacting Dark Energy and Modified Gravity in light of Planck results

20 Backup Constraints on DM-baryons interactions A. Erickcek et al. Phys.Rev.D76:042007,2007 Cross section for DM particles and nucleons Values inside the coloured contours are ruled out! Valentina Salvatelli Interacting Dark Energy and Modified Gravity in light of Planck results

21 Backup Coupled Quintessence Constraints Models in the DEvel frame V.Pe]orino astro- ph.co: Green=Planck+WP+BAO Blue = Planck+WP+HST Valentina Salvatelli Interacting Dark Energy and Modified Gravity in light of Planck results