WMAP: Recent Results and Dark Energy

1. WMAP: Recent Results and Dark Energy L. Page, STScI, May 2008

2. A 6 parameter model agrees with virtually all cosmological measurements regardless of redshift or method. The model assumes a flat geometry, a new form of matter, something that mimics a cosmological constant, and a deviation from scale invariance ( =1, ~2.5-3).

3. WMAP5 + SN& BAO WMAP5 only Models based on some kind of field theory of the early universe predict ns.

4. What does the CMB ALONE tell us about Dark Energy? NOTHING! (one more bit of information is needed)

5. CMB alone tells us we are on the “geometric degeneracy” line closed “Geometric Degeneracy” open { WMAP5 only best fit LCDM Lewis & Bridle ’02 Assume flatness Reduced WMAP3 = 1.045 WMAP5

6. What’s new for WMAP5? Selected highlights: • Calibration uncertainty now 0.2% (Hinshaw et al. 2008) • Full reanalysis of the main beam profiles, near lobes, and sidelobes (Hill et al. 2008). 1% shift in solid angle, uncertainties halved. • Developed new foreground cleaning methods for temperature (Gold et al. 2008) and polarization (Dunkley et al. 2008). However, basic results use original methods. • Nominal sky mask updated to “KQ85” (keeps 85%) vs Kp2 (keeps 97%) plus ~750 sources. (Gold et al., Wright et al. 2008)

7. Why care about the beam profiles? Three different spectra that differ only in spectral index. The black line is the best WMAP model.

8. Spectral Index Normalize the spectra to l=220 (mimics ns-amplitude degeneracy) The two window functions are for 0.1 deg FWHM beams with a 1% difference in solid angle. Only WMAP has achieved anything like this accuracy.

9. Spectral Index Divide by fractional window function. Conclusion: To probe the index the beams need to be understood to the 1% level. In addition, there are astrophysical challenges.

10. Full beam reanalysis led to: Consistent with earlier error bars but systematically higher. Hill et al. 2008

11. 23 GHz 125 mK The Data 33 GHz 67 mK WMAP5-WMAP3 41 GHz 48 mK 61 GHz 24 mK 94 GHz 17 mK Hinshaw et al. 2008

12. WMAP5 TT&TE Spectra 3 yr Particle horizon at decoupling ACBAR and CBI go to l=3000 Nolta et al, Hinshaw et al. 2008

13. New Polarization Maps Hinshaw et al. 2008

14. EE Power Spectrum Uncertainties include cosmic variance. l by l After accounting for foreground emission, the BB, EB, TB spectra are all consistent with zero. Nolta et al. 2008

15. Optical Depth, The square of the optical depth is essentially the average of the low l EE data. Of course, the quoted values come from the full analysis. Hinshaw et al. 2008

16. Analysis of curvature (and thus the presence of w=-1 Dark Energy) With the HST prior, h=0.72 +/- 0.08, -0.052< <0.013 (95%cl) k

17. Now add BAO and supernovae By adding BAO and SNIa, we find: -0.0181 < Ωk < 0.0071 (95% CL) Can convert to limits on the curvature radius of the universe: For negatively curved space (Ωk>1): R>23/h Gpc For positively curved space (Ωk<1): R>36/h Gpc Komatsu et al 2008

18. Now relax flatness and w=-1 assumptions Need both SN and BAO to limit the curvature and the dark energy equation of state For combined data, w= -0.97 +- 0.06 Komatsu et al 2008

19. Early Universe: WMAP consistent with power law Komatsu et al 2008 No significant running index is observed. WMAP-only: dns/dlnk = -0.037 +/- 0.028 WMAP+BAO+SN: dns/dlnk = -0.032 +/- 0.020 (Note that 1 parameter is added) Dunkley et al 2008

20. Early Universe: Limits on Gravitational Waves Use WMAP to constrain tensor-to-scalar ratio: tensors produce B-mode polarization, but also a large-scale temperature signal. (Currently low-l BB limits r < 20) Komatsu et al 2008 Dunkley et al 2008 • With all data: r < 0.20 (95% CL)

21. WMAP A partnership between NASA/GSFC and Princeton Science Team: NASA/GSFC Bob Hill Gary Hinshaw Al Kogut Michele Limon Nils Odegard Janet Weiland Ed Wollack Johns Hopkins Chuck Bennett (PI) Ben Gold David Larson UCLA Ned Wright Brown Greg Tucker Chicago Stephan Meyer Hiranya Peiris UT Austin Eiichiro Komatsu Princeton Norm Jarosik Lyman Page David Spergel CITA Olivier Dore Mike Nolta UAB Licia Verde UBC Mark Halpern Oxford Jo Dunkley Microsoft Chris Barnes Cornell Rachel Bean

22. THANK YOU

23. The quadrupole is not anomalously low. For the full sky, the 2-pt correlation function is not anomalous. Most “detections” of non-Gaussianity are based on a posteriori statistics. That is, one seeks any oddity in the maps and quantifies it. The North-South asymmetry was visible in the COBE data. Non-Gaussianity It would be wonderful to find a clear signature of cosmic non-Gaussianity. The WMAP team has not found one yet.

24. Non-Gaussianity • Look for non-Gaussianity by looking for non-zero bispectrum = 3 point function • Define ‘fNL’ using curvature fluctuations: Φ(x)=Φgauss(x)+fNL[Φgauss(x)]2 • -9 < fNL(local) < 111 (95% cl) (Komatsu et al 2008) • -151 < fNL(equilateral) < 253 (95% cl) (Komatsu et al 2008)

25. Alignment? (de Oliveira-Costs et al. 2004) A significant fraction of the full-sky quadrupole comes from: (Hajian 2007) Detection of SH persists! Note “fingers” present in the southern Galactic hemisphere. Largest effect in almost ecliptic coord. Extra cold spot: (Vielva et al. 2004, Cruz et al. gave 1.8% prob. 2005)