Cosmology after Planck

Transcription

1 Cosmology after Planck Raphael Flauger Rencontres de Moriond, March 23, 2014

2 Looking back Until ca data was consistent with defects (such as strings) generating the primordial perturbations. (Pen, Seljak, Turok 1997)

3 Looking back (Jaffe et al. 2001) Shortly after it became clear that defects were not the dominant source of primordial perturbations.

4 Looking back Perturbations exist on scales larger than the Hubble radius at recombination. Implies these perturbations already existed at recombination Together with General Relativity it means they existed before the hot big bang!

5 Looking back (Hinshaw et al. 2012)

6 Planck (Ade et al. 2013)

7 Planck Seven to eight acoustic peaks measured with a single experiment. LCDM with inflationary spectrum of perturbations continues to fit the data remarkably well. WMAP9+ACT PLANCK+WP n s Ω c h 2 Ω b h 2 H ± ± ± ± ± ± ± ±1.2

8 Fig % and 95% confidence regions on one-parameter extensions of the base ΛCDM model for Planck+WP Planck+WP+BAO (blue). Horizontal dashed lines correspond to the fixed base model parameter value, and vertical da Ωbh Ωch 2 ns H σ w r dn s /d ln k Planck Y P N eff Σm ν [ev] Ω K

9 Planck Lensing map and power spectrum No large non-gaussianity SZ, CIB, CO, dust,... soon there will be polarization maps Fig. 12. Planck measurements of the lensing power spectrum compared to the prediction for the best-fitting Planck+WP+highL ΛCDM model parameters. In the top panel, the data points are the measured bandpowers and ±1 σ error ranges from the diagonal of the covariance matrix. The measured bandpowers are compared to the C φφ in the best-fit model (black line). The grey region shows the 1 σ range in C φφ due to ΛCDM parameter uncertainties. The lower panel shows the differences between the bandpower amplitudes  i and the predictions for their expectation values in the best-fit model, A theory i.

10 Mild Tensions

11 The Hubble Constant Hinshaw et al Reid et al UGC 3789 WMAP+ACT Riess et al NGC 4258 LMC MW Ade et al Planck NGC 4258 Efstathiou 2013 LMC Spergel, Flauger, Hlozek 2013 MW Planck H 0 /(km/s/mpc)

12 The Hubble Constant The CMB experiments favor low values of the Hubble constant. The Cepheid/SNIa measurements of the Hubble constant favor larger values, but calibration of the first rung of the distance ladder remains a challenge. New physics typically decreases the tension but is not sufficient to eliminate it. More accurate local measurements would be extremely valuable. Megamasers are promising but statistics is still limited.

13 Clustering 0 tsz power spectrum Paper XXI CMB Paper XVI P/Pmax σ 8 Ωm

14 Clustering tsz power spectrum (Hill, Spergel 2013) tszxlensing (Hill, Spergel 2013) tszxx-ray (Hajian et al. 2013) P/Pmax CMB Paper XVI Spergel, Flauger, Hlozek σ 8 Ωm

15 Clustering The CMB predicts slightly stronger clustering than observed in low redshift data (SZ, lensing,...). The low redshift measurements are challenging for several reasons (foregrounds, cluster mass calibration,...). Better understanding of the low redshift systematics may eliminate the tension or point towards new physics such as neutrino masses.

16 Planck+BAO+JLA Neutrino Masses The race for neutrino mass and hierarchy cosmology Heidelberg Moscow inverted particle physics normal

17 Combining with New Data Sets

18 Planck+BAO DR11 and 6dF isotropic BAO data CAMspec CrossSpec WMAP9+ACT

19 Planck+BAO+JLA CrossSpec+WP +JLA +BAO +BAO+JLA Ω b h ± ± ± ± Ω c h ± ± ± ± τ ± ± ± ± n s ± ± ± ± H ± ± ± ± 0.62 Ω m ± ± ± ± σ ± ± ± ± (Spectra, covariance matrix from Spergel, Flauger, Hlozek 2013)

20 BICEP2

21 A Map of B-modes BICEP2: E signal Simulation: E from lensed ΛCDM+noise µK 1.7µK µk BICEP2: B signal Simulation: B from lensed ΛCDM+noise Declination [deg.] µK 0.3µK µk Right ascension [deg.]

22 The Power Spectrum 10 2 BICEP2 BICEP QUAD QUIET Q QUIET W CBI Boomerang DASI WMAP CAPMAP l(l+1)c l BB /2π [µk 2 ] r=0.2 lensing Multipole

23 The Power Spectrum B2xB2 B2xB1c B2xKeck (preliminary) l(l+1)c l BB /2π [µk 2 ] Multipole

24 Primordial B-modes? The measurement is extremely challenging. It requires exquisit control over differential gain, differential pointing, beams, foregrounds... These and many more systematics are briefly discussed in the BICEP2 paper. It will be interesting to see the promised paper on systematics. The BICEP2xKeck spectra look promising. The BICEP team has already seen more data than we have. The value of r may come down perhaps even below r=0.1, but it seems this is a detection of primordial B- modes.

25 Parameter Constraints What is agreement to some is tension to others. V φ 2 V φ Recall that foregrounds were not subtracted, and that there are additional indications r may decrease. (Spectra, covariance matrix from Spergel, Flauger, Hlozek 2013)

26 Parameter Constraints More on the tension χ 2 eff running broken power law CAMspec 6 12 CrossSpec 4 10 (broken power law: allow for different scalar spectral index above and below k =0.008 Mpc 1 ) (Recall that foregrounds are not accounted for and increase the tension)

27 B-modes and Planck Planck will clarify whether the signal could be from foregrounds. Simulations suggest Planck could see r 0.1 at 80, but systematics remain challenging. EE C l [µk 2 CMB] Planck EE from TT best-fit noise bandpass leakage calibration leakage polarisation orientation error polarisation efficiency error EE C l [µk 2 CMB] Planck EE from TT best-fit noise bandpass leakage calibration leakage polarisation orientation error polarisation efficiency error GHz multipole GHz multipole EE C l [µk 2 CMB] Planck EE from TT best-fit noise bandpass leakage calibration leakage polarisation orientation error polarisation efficiency error EE C l [µk 2 CMB] Planck EE from TT best-fit noise bandpass leakage calibration leakage polarisation orientation error polarisation efficiency error GHz multipole GHz multipole

28 Nature of B-modes Even if the signal is primordial, we strictly speaking do not yet know that it is inflationary. Can we tell the difference between different alternatives (self-ordering scalar fields, string or particle production during inflation,...)? Correlation on large scales (CLASS, LiteBIRD,...) Non-Gaussianity (LSS) Consistency relation...

29 Tensor Spectral Index Take with a big grain of salt PnT n T fit based only on lowest 4 data points broken LCDM+r The tensor spectral index is very blue. This is not due to the B-mode spectrum, but due to the excess of power on large scales in temperature. 1C2ΠΜK broken LCDM+r+nT (However, recall that the data as is includes foregrounds.)

30 Some Implications Inflation is our best candidate to explain the signal. Assuming the signal originates from quantum fluctuations of the spacetime metric during single-field slow-roll inflation, the detection implies H(t ) GeV or V 1/ GeV. The field range is roughly Planckian (Lyth 1996, Choudhury, Mazumdar 2013)

31 Some Implications Theory Our theories make meaningful predictions at these high energies. We should think harder about large field models. Experiment If the signal is this large a 1% measurement of r is achievable! Even the inflationary consistency condition becomes testable.

32 For particle physics Some Implications The inflationary energy scale is very close to the SUSY GUT scale No cosmologically stable moduli with m<10 14 GeV In standard cosmological scenarios, the gravitino is either light m<o(10ev ) or m>o(100 TeV) The mass of the graviton is bounded m ev...

33 Conclusions Planck has provided us with beautiful temperature map and will soon provide polarization maps New large scale structure surveys are beginning to take data BICEP2 seems to have detected primordial gravitational waves The Planck results have forced us to reexamine astrophysical measurements, BICEP2 finally forces us to work harder on the theory side as well Cosmology promises to be exciting for years to come for both theorists and experimentalists

34 Thank you!