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CMB and early Universe physics. 郭宗宽. 北京师范大学天文系 2013.12.12. c ontent. CMB physics Recent Planck results Anomalies in CMB map. I. CMB physics. CMB 的形成 CMB 的发现和探测实验 CMB 的数据分析 CMB 各向异性的物理 起源. 1. CMB 的形成. t he reaction rate vs. the expansion rate. decoupling during recombination.
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CMB and early Universe physics 郭宗宽 北京师范大学天文系 2013.12.12
content • CMB physics • Recent Planck results • Anomalies in CMB map
I. CMB physics • CMB的形成 • CMB的发现和探测实验 • CMB的数据分析 • CMB各向异性的物理起源
1. CMB的形成 the reaction rate vs. the expansion rate decoupling during recombination
2. CMB的发现和探测实验 • The CMB was first predicted by G. Gamow, R. Alpher and R. Herman in 1948 T~5 K • the first discovery of the CMB radiation in 1964-1965 the Nobel Prize in Physics 1978: A.A. Penzias and R.W. Wilson • It is interpreted by R. Wilson, B. Burke, R. Dicke and J. Peebles • in 1965.
Hot big bang • COBE (Cosmic Background Explorer) - the first generation CMB experiment, launched on 18 Nov. 1989, 4 years the Nobel Prize in Physics 2006: J.C. Mather and G.F. Smoot J.C. Mather G.F. Smoot (DMR) isotropy
the COBE satellite experiments: • the Far InfraRed Absolute Spectrophotometer (FIRAS) team • the Differential Microwave Radiometer (DMR) team • advantages of satellite experiments: • no atmospheric thermal emission • full-sky map
WMAP (Wilkinson Microwave Anisotropy Probe) - the second generation CMB experiment, launched on 30 June 2001, 9 years 141°
23 GHz 33 GHz 41 GHz 61 GHz • free-free emission: electron-ion scattering • synchrotron emission: the acceleration of cosmic ray electrons in magnetic fields • thermal emission from dust 94 GHz
foreground mask • angular power spectrum of CMB
WMAP science team publications 2003, WMAP1, 14 papers, cited by 6873 records 2007, WMAP3, 5papers, cited by 5289 records 2009, WMAP5, 8papers, cited by 3527records 2011, WMAP7, 6papers, cited by 3803 records 2012, WMAP9, 2papers, cited by 303 records We have entered a new era of precision cosmology.
Planck - the third generation CMB experiment, launched on 14 May 2009, 30 months, 5 full-sky surveys LFI: 30,44,70 GHz HFI : 100,143,217,353,545,857 GHz • high sensitivity • wide frequency • full-sky coverage • high resolution ~7º,15′,5′
cosmological parameters the temperature angular power spectrum 20 March 2013, 29 papers
nextgeneration space-based CMB experiment • NASA: CMBPol • ESA: COrE
Other experiments • ground-based experiments • ACBAR, BICEP, CBI, VSA, QUaD, BICEP2, … • ACT, ACTPol from 2013 • SPT, SPTpol from 2012 • QUBIC (r ~ 0.01, bolometer, interferometer) • balloon-borne experiments • BOOMRANG, MAXIMA, … • EBEX • Spider
South Pole Telescope (SPT) 10 meter telescope 3 frequencies (95, 150 and 220 GHz) arXiv:1105.3182: SPT+WMAP7+BAO+H0 arXiv:1212.6267: SPT+WMAP7+BAO+H0
Atacama Cosmology Telescope (ACT) 3 frequencies (148, 218, and 277 GHz) 6 meter telescope
3. CMB的数据分析 time-ordered data full sky map spectrum parameter estimates time-ordered data the temperature anisotropies can be expanded in spherical harmonics
for Gaussian random fluctuations, the statistical properties of the temperature field are determined by the angular power spectrum For a full sky, noiseless experiments, cosmological parameter estimation likelihood function for a full sky: the sky-cut, MCMC
4. CMB各向异性的物理起源 • primary CMB anisotropies (at recombination) inflation model (Alan H. Guth in 1981) primordial power spectrum of perturbations angular power spectrum of CMB anisotropies • secondary CMB anisotropies (after recombination) thermal/kinetic Sunyaev-Zel’dovich effect integrated Sachs-Wolf effect reionization weak lensing effect
inflation model V (φ) reheating inflation φ for slow-roll inflation, the primordial power spectra of scalar/tensor perturbations:
Phase transition: Old inflation, New inflation • Kinetic term: K-inflation, Tachyon inflation, G-inflation • Modified gravity: R^2-inflation, Brane-world inflation, Extended inflation, GB-coupled inflation • Multiple fields: Hybrid inflation (waterfall field), Assisted inflation, N-flation, Matrix-inflation, Double inflation, Curvaton-type inflation, Modulated inflation • Slow-roll parameter: Large-field inflation, Small-field inflation • Example: Chaotic inflation, Power-law inflation, Eternal inflation • Interaction: Warm inflation, Trapped inflation • Initial condition: Bounce inflation, Cyclic inflation • Particle physics: Higgs inflation, Super-natural inflation • SUSY: SUSY F-term inflation, SUSY D-term inflation, SUSY P-term inflation, SUGRA inflation • String theory: open string inflationary models: D3/brane inflation, Inflection point inflation, DBI inflation,Wilsonline inflation, D3-D7 inflation closed string inflationary models: Racetrack inflation, N-flation, Axionmonodromy, Kahler moduli inflation, Fibre inflation, Poly-instantoninflaiton
The stronger the contraction, the higher these peaks should be.
II. Recent Planck results • the six-parameter ΛCDM model • beyond the standard model • primordial non-Gaussianity • Inflationary models • beyond slow-roll inflation • ……
Cepheid+SNeIa, discrepant at the 2.5 σ level • SNLS, discrepant at the 2σ level • cosmic shear, discrepant at the 2 σlevel, • galaxy cluster, discrepant at the 3 σlevel,
2. beyond the standard model dark matter annihilation, primordial magnetic fields, fine-structure constant, α/α0=0.9936±0.0043
LIV in the neutrino sector the deformed dispersion relation • CMB anisotropies: (1) the energy density (2) the Boltzmann equation in the synchronous gauge ZK Guo, QG Huang, RG Cai, YZ Zhang, arXiv:1206.5588
Big Bang nucleosynthesis: (1) the energy density (2) the weak reaction rate in the Lorentz-violating extension of the Standard Model (D.Colladay, A.KosteleckyarXiv:hep-ph/9809521) • cosmological constraints: ZK Guo, JW Hu, arXiv:1303.2813
4. inflationary models slow-roll inflation (three parameters): As, ns, r, nt=-r/8 The data favor a concave potential rather than a convex one.
Inflation coupled to a GB term • motivations: • higher-order corrections • a flat potential • a large tensor perturbation • our model: where In power-law inflationary model, the GB coupling drives acceleration of the Universe, but ultra-violet instabilities of either scalar or tensor perturbations show up on small scales. • to generalize it to slow-roll inflation ZK Guo, D.J. Schwarz, arXiv:0907.0427; ZK Guo, D.J. Schwarz, arXiv:1001.1897; PX Jiang, JW Hu, ZK Guo, arXiv:1310.5579
introducing Hubble and GB flow parameters: the predicted tensor-to-scalar ratio and spectral indices: The degeneracy of standard consistency relation is broken by the GB coupling. The GB coupling may lead to a reductionof the tensor-to-scalar ratio.
5. beyond slow-roll inflation Three parameterizations: • wiggles model • step-inflation model • cutoff model
reconstruction of power spectrum • parameterization: • scale-invariant(As) • power-law (As, ns) • running spectral index (As, ns, as) • our method: • advantages: • It is easy to detect deviations from a scale-invariant or a power-law spectrum. • Negative values of the spectrum can be avoided by using ln P(k) instead of P(k). • It reduces to the scale-invariant or power-law spectrum as a special case when N bin= 1, 2, respectively.
WMAP7+H0+BAO WMAP7+H0+BAO WMAP7+ACT+H0+BAO WMAP7+ACT+H0+BAO The HZ spectrum is disfavored at 2and the power-law spectrum is a good fit to the data. ZK Guo, D.J. Schwarz, YZ Zhang, arXiv:1105.5916; ZK Guo, YZ Zhang, arXiv:1109.0067; ZK Guo, YZ Zhang, arXiv:1201.1538
III. Anomalies in CMB map • the quadrupole-octopole alignment • power deficit at low-l • parity asymmetry • hemispherical asymmetry • the cold spot • ……
4. hemispherical asymmetry the CMB temperature sky maps is modeled as C.Gordon, W.Hu, D.Hutererand T.M.Crawford, arXiv:astro-ph/0509301 the likelihood is given by H.K.Eriksen, A.J.Banday, K.M.Gorski, F.K.Hansenand P.B.Lilje, arXiv:astro-ph/0701089
H.K.Eriksen, A.J.Banday, K.M.Gorski, F.K.Hansenand P.B.Lilje, arXiv:astro-ph/0701089 • WMAP3: (l, b) = (225◦,−27◦), A=0.114 • WMAP5: (l, b) = (224◦,−22◦), A=0.0720.022 • Planck: J.Hoftuft, H.K.Eriksen, A.J.Banday, K.M.Gorski, F.K.Hansenand P.B.Lilje, arXiv:0903.1229 P.A.R.Ade et al. [Planck Collaboration], arXiv:1303.5083
dependence on smoothing scale preferred dipole directions
Comment 1: the dipole anisotropy induced by our velocity the temperature and direction in the observed frame the inferred temperature fluctuations (l, b) = (264◦,48◦)
Comment 2: the dipole anisotropy in k-space the power spectrum is parameterized as [astro-ph/0701357] the north and south ecliptic poles WMAP5 data give a 9σ detection [arXiv:0911.0150] Planck data [arXiv:1310.1605]
Explanations: • a parameterization[astro-ph/0509301] • our peculiar motion[arXiv:1304.3506] • a gauge field[arXiv:1302.7304] • anisotropic metric[arXiv:1303.6058] • a modulation of a cosmological parameter [arXiv:1303.6949] • a superhorizon perturbation [arXiv:0806.0377] • ……
a super-horizon perturbation the Sachs-Wolfe effect the diploe modulation of curvature perturbation the asymmetry A is
the GZ effect (the Sachs-Wolfe approximation) observational constraint For a single-field slow-roll inflation,
primordial power spectrum: For the bounce inflation, ZG Liu, ZK Guo, YS Piao, arXiv:1304.6527