The dawn of b mode in the University

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The dawn of b mode in the University

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The dawn of B mode cosmology ! Strings 2014 0.25 0.00 Tensor-to-Scalar Ratio (r0.002 ) 0.05 0.10 0.15 0.20 Planck+WP Planck+WP+highL Planck+WP+BAO Natural Inflation Power law inflation Low Scale SSB SUSY Co nv Co ex nca ve R Inflation V V 2/3 V V N =50 0.94 0.96 0.98 Primordial Tilt (ns ) 1.00 Planck N =60 Fig Marginalized joint 68% and 95% CL regions for ns and r0.002 from Planck in combination with other data sets compared to the theoretical predictions of selected inflationary models reheating priors allowing N⇤ < 50 could reconcile this model with the Planck data Exponential potential and power law inflation Inflation with an exponential potential V( ) = ⇤4 exp Mpl ! (35) is called power law inflation (Lucchin & Matarrese, 1985), because the exact solution for the scale factor is given by a(t) / t2/ This model is incomplete, since inflation would not end without an additional mechanism to stop it Assuming such a mechanism exists and leaves predictions for cosmological perturbations unmodified, this class of models predicts r = 8(ns 1) and is now outside the joint 99.7% CL contour Inverse power law potential Intermediate models (Barrow, 1990; Muslimov, 1990) with inverse power law potentials V( ) = ⇤4 Mpl ! (36) lead to inflation with a(t) / exp(At f ), with A > and < f < 1, where f = 4/(4 + ) and > In intermediate inflation there is no natural end to inflation, but if the exit mechanism leaves the inflationary predictions on cosmological perturbations unmodified, this class of models predicts r ⇡ (ns 1)/( 2) (Barrow & Liddle, 1993) It is disfavoured, being outside the joint 95% CL contour for any Hill-top models In another interesting class of potentials, the inflaton rolls away from an unstable equilibrium as in the first new inflationary models (Albrecht & Steinhardt, 1982; Linde, 1982) We consider ! p V( ) ⇡ ⇤4 + , (37) µp where the ellipsis indicates higher order terms negligible during inflation, but needed to ensure the positiveness of the potential later on An exponent of p = is allowed only as a large field inflationary model and predicts ns ⇡ 4Mpl /µ2 + 3r/8 and 2 r ⇡ 32 ⇤ Mpl /µ This potential leads to predictions in agreement with Planck+WP+BAO joint 95% CL contours for superPlanckian values of µ, i.e., µ & Mpl Models with p predict ns ⇡ (2/N)(p 1)/(p 2) when r ⇠ The hill-top potential with p = lies outside the BICEP The interpretation of the BICEP2 results Flauger, Hill & Spergel: Revised Estimates of the level of dust in the BICEP patch DDM-P1+lensing 0.05 Ê ¥ 0.04 Ê Ê 0.03 0.02 Ê Ê Ê Ê ¥ ¥Ê ¥ Ê ¥ ¥ 0.05 Ê ¥ 0.04 Ê Ê 0.03 0.02 Ê Ê ¥ 0.01 ¥ ¥ 50 0.06 Ê Ê ¥ ¥Ê ¥ Ê ¥ ¥ 150 200 { 250 300 50 0.05 Ê ¥ 0.04 Ê Ê 0.03 0.02 Ê Ê ¥ 0.01 ¥ ¥ 100 {H{+1LC{,BB ê2p@mK2 D 0.06 {H{+1LC{,BB ê2p@mK2 D {H{+1LC{,BB ê2p@mK2 D 0.06 0.01 NHI-lensing DDM-P2+lensing Ê Ê ¥ ¥Ê ¥ Ê ¥ ¥ ¥ ¥ ¥ 100 150 200 { 250 300 50 100 150 200 250 300 { Bernard’s polarization fraction FIG Mortonson 4: Comparison of&several predictions for the 150after GHz signal versus the reported ⇥ Bicep2 and the preliminary Seljak: Constraints marginalizing over •Bicep2 foregrounds Q and U from Boulanger, T from nominal Planck data, Bicep2 ⇥ Keck measurements The predictions are a combination of the dust polarization and lensing CMBsignal removed, all the zero predicted levels set from LAB HI data signal for standard cosmological parameters Panel (a) is based on DDM-P1, which assumes that the dust polarization signal is proportional to the dust intensity (extrapolated from 353 GHz) times the mean polarization fraction (based on our CIBcorrected map; see section III) The band represents the countours derived from a set of 48 DDM-P1 models Panel (b) shows DDM-P2, with polarization fractions from our CIB-corrected map, and polarization direction based on starlight measurements, the PSM, or [33] Panel (c) uses the column density of neutral hydrogen in the Bicep2 region inferred from the optical depth at 353 GHz to estimate the dust foreground In this panel, the band reflects the uncertainty in the extrapolation of the scaling relation to low column densities as well as the uncertainty in the rescaling from 353 GHz to 150 GHz this region has been selected by the Bicep2 team for its low dust extinction, few starlight polarization data have 20% been collected within the field However, we found seven significant detections (P/ P > 01) along sightlines to stars at least 100 pc above the Galactic plane Two of them are for the same star, but observed by di↵erent teams, with does not look like Bernard’s map, p=0.092 in BICEP patch both observations above The polarization angle of the dust emission derived from the corrected latter is 154.5polarization The mean Flauger: CIB fraction and median angles derived from all significant detections in the region are respectively 171.1 and 160.4 , in good agreement with that derived from the detections In a first class of models, we thus take the polarization angle m ΩzΛ = COBE increased by about 10% at ℓ ∼ 50 and decreased about recently for inclusion in this analysis, but we include 5% for ℓ ∼ 100 − 200, thereby nudging the first peak a them in the online combined power spectrum described tad to the right below m H(z) H0 H(z) ΩΛ , Ground/Balloon (pre-WMAP) (13) with H(z) given by equation (5) The power spectrum Pδnl (k) needed in equation (3) is the nonlinear one rather than the linear one Pδl (k) given by equation (10) Based on a pioneering idea of Hamilton et al [62], a series of approximations [59,63–65] have been developed for approximating the former using the latter In terms of the dimensionless power 4π k Pδ (k), (14) ∆2 (k) ≡ (2π)3 the linear power ∆l on scale kl is approximately related – 37 – to the nonlinear power ∆ nl on a smaller nonlinear scale knl We use the Peacock & Dodds’ approximation [65], where this mapping is given by ∆2nl (knl ) = fnl ∆2l (kl ) (15) and kl = + ∆2nl (knl ) −1/3 knl , (16) WMAP with a fitting function ⎧ ⎫1/β ⎪ ⎨ + Bβx + (Ax)αβ ⎪ ⎬ fnl (x) = x , β ⎪ ⎪ ⎩ + (Ax)α g(0)3 ⎭ (V x1/2 ) FIG CMB data used in our analysis Error bars not FIG Combination of data from Figure These error bars include calibration or beam errors which allow substantial vertical include the effects of beam and calibration uncertainties, which shifting and tilting for some experiments (these effects are included cause long-range correlations of order 10% over the peaks In addiin our analysis) tion, points tend to be anti-correlated with their nearest neighbors, typically at the level of 10-20% The curve shows our model best We combine these measurements into a single set of 28 fitting CMB+LSS data (second last column in Table 2) (17) parametrized by A = 0.482(1 + neff /3)−0.947 , B = 0.226(1 + neff /3)−1.778 , α = 3.310(1 + neff /3)−0.224 , β = 0.862(1 + neff /3)−0.287 , V = 11.55(1 + neff /3)−0.423 th In G as al ou eff Planck Collaboration: Cosmological parameters (18) (19) (20) (21) (22) band powers shown in Figure and Table using the method of [30] as improved in [31], including calibration and beam uncertainties, which effectively calibrates the experiments against each other Since our compressed band powers dℓ are simply linear combinations of the original measurements, they can be analyzed ignoring the details of how they were constructed, being completely characterized by a window matrix W: Here g(0) is the linear growth factor of equation (11) evaluated at z = and neff ≡ d ln Pδl (k)/d ln kl is the effective logarithmic slope of the linear power spectrum Fig 8.—evaluated The final angular 1)Cl /2π, obtained from the be 28 cross-power spectra, atpower kl spectrum, Sincel(l +this slope should evaluated as described in §5 The data are plotted with 1σ measurement errors only which reflect the combined for model baryonic wiggles, we The compute neffthe uncertainty due a to noise, beam,without calibration, and source subtraction uncertainties solid line shows best-fit ΛCDM model et al (2003).&The grey band around the modelwith is the 1σ uncertainty using anfrom theSpergel Eisenstein Hu fitting function baryon due to cosmic variance on the cut sky For this plot, both the model and the error band have been binned oscillations turned with the same boundaries as the data, butoff they have been plotted as a splined curve to guide the eye On Ground/(pre-Planck) Wiℓ δTℓ2 , ⟨di ⟩ = (23) Table – Band powers combining the information from CMB data from Figure The 1st column gives the ℓ-bins used when combining the data, and can be ignored when interpreting the results The 2nd column gives the medians and characteristic widths of the window functions as detailed in the text The error bars in the 3rd column include the effects of calibration and beam uncertainty The full 28×28 correlation matrix and 28×2000 window matrix are available at www.hep.upenn.edu/ ∼ max/cmb/cmblsslens.html ℓ where δTℓ2 ≡ ℓ(ℓ + 1)Cℓ /2π is the angular power spectrum This matrix is available at the scale of this plot the unbinned model curve would be virtually indistinguishable from the binned curve except in the vicinity of the third peak Fig 10 Planck T T power spectrum The points in the upper panel show the maximum-likelihood estimates of the primary CMB spectrum computed as described in the text for the best-fit foreground and nuisance parameters of the Planck+WP+highL fit listed Kendrick M Smith,1 Cora Dvorkin,2 Latham Boyle,1 Neil Turok,1 Mark Halpern,3 Gary Hinshaw,3 and Ben Gold4 Perimeter Institute for Theoretical Physics, Waterloo ON N2L 2Y5 Institute for Advanced Study, School of Natural Sciences, Einstein Drive, Princeton, NJ 08540, USA Dept of Physics and Astronomy, University of British Columbia, Vancouver, BC Canada V6T 1Z1 Hamline University, Dept of Physics, 1536 Hewitt Avenue, Saint Paul, MN 55104 (Dated: April 2, 2014) 404.0373v1 [astro-ph.CO] Apr 2014 Planck Large angle power deficit The recent BICEP2 measurement of primordial gravity waves (r = 0.2+0.07 0.05 ) appears to be in tension with the upper limit from WMAP (r < 0.13 at 95% CL) and Planck (r < 0.11 at 95% CL) We carefully quantify the level of tension and show that it is very significant (around 0.1% unlikely) when the observed deficit of large-scale temperature power is taken into account We show that measurements of TE and EE power spectra in the near future will discriminate between the hypotheses that this tension is either a statistical fluke, or a sign of new physics We also discuss extensions of the standard cosmological model that relieve the tension, and some novel ways to constrain them PACS numbers: 10 Planck Collaboration: Constraints on inflation Model ⇤CDM + tensor Parameter ns r0.002 ln Lmax Planck+WP 0.9624 ± 0.0075 < 0.12 Planck+WP+lensing 0.9653 ± 0.0069 < 0.13 Planck + WP+high-` 0.9600 ± 0.0071 < 0.11 Planck+WP+BAO 0.9643 + 0.0059 < 0.12 -0.31 The BICEP2 collaboration’s potential detection of Bmode polarization in the cosmic background radiation Table Constraints on the primordial perturbation parameters in the ⇤CDM+r model from Planck combined with other data sets The constraints are(CMB) given at the pivot scale kjustifiably = 0.002 Mpc has ignited enormous excitement, signalling as it may the opening of a powerful new window onto the earliest moments of the big bang [1] The impliPlanck+WP cations are profound, including a possible confirmation Planck+WP+highL of cosmic inflation and exclusion of rival explanations for Co Planck+WP+BAO nve Co x the origin and structure of the cosmos Natural Inflation nca ve Power law inflation As the BICEP2 collaboration were Low careful to emphaScale SSB SUSY size, there is some tension between their value of the paR Inflation 2/3 V rameter r which controls the amplitude of the gravitaV tional wave signal, relative to other experiments BI2 V CEP2 detected B-mode polarization corresponding to V +0.06 r = 0.2+0.07 (or r = 0.16 after foreground subtracN =50 0.05 0.05 tion), as compared to upper bounds from N =60the large-scale 0.94 0.96 0.98 1.00 Primordial Tilt (ns ) power spectrum: r < 0.13 (WMAP) CMB temperature Fig Marginalized 95% CL regions for n and r atfrom Planck inCL combination sets compared to orjointr68% and < polarf < 1, manner, to point measurements of ACMB with the Planck data where f = 4/(4 + ) and > In intermediate inflation there is no natural end to inflation,or but ifresolve the exit mechanism leavesthe ization E-modes will either sharpen it in the inflationary predictions on cosmological perturbations unExponential potential and power law inflation modified, cosmological this class of models predicts r ⇡ (n 1)/( 2) near future, and to explore interpretations (Barrow & Liddle, 1993) It is disfavoured, being outside the Inflation with an exponential potential joint 95% CL contour for any In Fig 1,! we show current measurements of the tem- Adding tensors makes it worse 0.00 Tensor-to-Scalar Ratio (r0.002 ) 0.05 0.10 0.15 0.20 0.25 ⇤ s ⇤ 0.002 f s FIG 1: Current measurements of the CMB temperature power spectrum, from Planck (open circles), WMAP (closed circles), ACT (squares) and SPT (triangles) Error bars include noise variance only; the shaded region represents cosmic variance There is a small deficit of power on large angular scales relative to an r = model (solid curve) which becomes as BICEP2 suggests more statistically significant if r = 0.2 (dashed curve) From the bottom up: The simplest models ! • Inflationary background: scale invariant • Fluctuations of the clock: no fluctuations in the composition, or “local” non-Gaussianities • Simple history: Large tensors • Theory of the fluctuations valid all the way to the symmetry braking scale: cs = 1, no “equilateral” non-Gaussianities 10 Planck Collaboration: Constraints on inflation Model ⇤CDM + tensor Parameter ns r0.002 ln Lmax Planck+WP 0.9624 ± 0.0075 < 0.12 Planck+WP+lensing 0.9653 ± 0.0069 < 0.13 Planck + WP+high-` 0.9600 ± 0.0071 < 0.11 Planck+WP+BAO 0.9643 + 0.0059 < 0.12 -0.31 0.00 Tensor-to-Scalar Ratio (r0.002 ) 0.05 0.10 0.15 0.20 0.25 Table Constraints on the primordial perturbation parameters in the ⇤CDM+r model from Planck combined with other data Results sets Planck Collaboration: Planck 2013 The constraints are given at the pivot scale k⇤ = 0.002 Mpc Co nv Co ex nca ve good indication that no spurious NG features are present in the actual data set when compared to our simulations It should be noted that we found a similarly good level of Planck+WP agreement between Planck+WP+highL estimators for the non-primordial shapes of point sources and Planck+WP+BAO ISW-lensing, although we chose not to present those results here Natural Inflation in order to focus on the primordial shapes Finally, regarding the Power law inflation wavelet pipeline, the lower weight correlation and suboptimal Low Scale SSB SUSY error bars produce an expected larger scatterRwhen compared to Inflation the other estimators Nonetheless, the level of agreement is still 2/3 V of order , which is quite acceptable for consistency checks of V the optimal results Again, this MC expectation agrees with what V we see in our results on the real data V N =50 0.94 0.96 Results 0.98 1.00 N =60 XXIV Constraints on primordial NG Table Results for the fNL parameters of the primordial local, equilateral, and orthogonal shapes, determined by the KSW estimator from the SMICA foreground-cleaned map Both independent single-shape results and results marginalized over the point source bispectrum and with the ISW-lensing bias subtracted are reported; error bars are 68% CL Independent ISW-lensing subtracted KSW KSW SMICA Local Equilateral Orthogonal 9.8 ± 5.8 37 ± 75 46 ± 39 2.7 ± 5.8 42 ± 75 25 ± 39 Primordial Tilt (ns ) For our analysis of Planck data we considered foregroundcleaned maps obtained with the four component separation methods SMICA, NILC, SEVEM, and C-R For each map, fNL reheating priors allowing N⇤ < 50 could reconcile this model lead to inflation with a(t) / exp(At f ), with A > and < f < 1, amplitudes for the local, where equilateral, and orthogonal primordial with the Planck data f = 4/(4 + ) and > In intermediate inflation there Fig Marginalized joint 68% and 95% CL regions for ns and r0.002 from Planck in combination with other data sets compared to the theoretical predictions of selected inflationary models the standard shapes (local, equilateral, orthogonal), see Table However, both the binned and modal estimators achieve optimal performance and an extremely high correlation for the stan- Single time scale histories Changes over one e-fold ✏H H˙ =| | HH ✏H˙ ¨ H =| | H H˙ ✏X X˙ =| | HX If both are of the same size then the gravitational wave contribution is substantial r = 16✏H Of course it is easy to open a hierarchy between these two parameters H(t) = H? + H(t/t? ) H ⇠ 1/t? ! ✏H ⇠ ✏2H˙ ✏H H ⇠ ✏H˙ H? P (k ) ⇤ hanges rof=the t inflaton potential spoil the delicate flatness requir Unless the enjoysthreaten further one expects that rather to parameterize the uncth ⇡ 16✏ ⇡ UV 8nand , therefore (22) tosymmetries, ttheory PR (k ) thisunity ⇤order nflation Note that appliesThus, not just to the light degrees freedom, even field rateaofof the Universe during whenever traverses distance ofbut order Mto a pl inthi masses near the Planck scale: integrating Planck-scale degrees freedom (i.s on wint generically provide obse by a suitably powerfulout symmetry, the constraints e↵ectiveofLagrangian receives s the consistency relation This consistency relationoperators physics this to period ouplings of order infinite unity) introduces Planck-suppressed in during the action series of higher-dimension operators In e↵ective order have For infl ll to understand how r is connected to the evolution slow-roll evolution, r(N ) doesn’t much but andThe oneinflation may obtain the following questionsDuring in particle physics, such operators areevolve negligible, in they play an Eq impa first two terms of course be approximately flat over a super-Planckian range If this is n: relation [27] ole second term being roughly Z N it requires a conspiracy among the tuning, infinitely many coefficients, wh ⇣ p appear are determined, as r ⌘1/2 byoccurs malization rapidly, of orthi The particular operators which always, the symmetries = O(1) ⇥ , ⇡ p dN r (23) fine-tuning’ (compare thisMto the eta problem onlymagnitude requires tuo 0.01! which pl symmetry radiation-like, the Mpl As an nergy action example, imposing only the on the inflaton leads For most reasonable inflation m ollowing e↵ective action: where r(N cmb ) is the tensor-to-scalar ratio on CMB scales Large values of the tensor-to- UV sensitivity 28.4.2 Shift Symmetry elation, called thetherefore Lyth bound (Lyth, the third term ⇠ 10, motivatin r > 0.01, correlate with 1997), > Mpl imor large-field inflation ✓< 60.◆Nonetheless, mass 2p X inflaton variation1 of the order of the Planck 50 < N m ⇥ ⇤ ⇤ 1 2 4 There way is to useful controlptothis series ofpossible corrections: Le↵ (r )&= 0.01 (@ Such )is a sensible mthreshold + are ⌫infinite + · · · (Liddlo p (@in) principle produce a 2 Mpl p=1 that forbids the inflaton coupling other fields e and small13 fieldsymmetry inflationary models with respect to from of Sect wetowill mark the in Primordial Spectra structure of the inflaton potential Such a shifteye symmetry, nd reader’s nless the UV symmetries, one expects thatfluctuations the coefficients and ⌫p Thetheory results enjoys for the further power spectra of the scalar and tensor createdpby inflat rder unity Thus, whenever traverses a distance of order Mpl in!a direction that is not pro + const , Shift symmetry forbids these terms H substantial corrections fr y a suitably powerful symmetry, the e↵ective Lagrangian receives 2 , s (k) ⌘ R (k) = 2 " Mplinflation, nfinite series of higher-dimension operators In order to8⇡ have the potential sho protects the inflaton potential in a natural way k=aH ourse be approximately super-Planckian range If2the this is to arise by accident or b H 2action In flat the over caseawith a shift symmetry, of chaotic inflation 2 h (k) = 2 which has , been termed ‘func t (k) ⌘ uning, it requires a conspiracy among infinitely many coefficients, ⇡ Mpl k=aH gravity Symmetry needs to be respected by quantum of one ne-tuning’ (compare this to the eta problem which only requires tuning masspparame 8.4.2 where Shift Symmetry with small coefficient Le↵ ( ) = (@ ) p , d ln H "= dN is ‘technically natural’ However, because p The origin of the seeds of structure The idea that the source of fluctuations are vacuum fluctuations of a slowly rolling scalar field which served as the clock that determined when inflation ends (ie slow-roll inflation) is only tested through our study of non-Gaussianities In this area Planck has made tremendous progress After Planck we can say that this idea has survived non-trivial tests However a significant fraction of parameter space is still unexplored ! ! ! “Inflation” Hot Big Bang - Radiation era Anything interesting here? BBN Decoupling Today Reheating Were fluctuations converted into curvature fluctuations at the beginning/during the hot big bang? Did super-horizon modes ever produce locally observable differences that modulate the equation of state? Robust signature: Primordial non-Gaussiniaty k ⌧ k , k1 Large Scale Structure In search for more modes Summary There are several interesting thresholds we want to cross observationally to improve our understanding of the epoch during which the seeds of structure were created ! Our experimental colleagues have arrived to the “gravity wave” threshold ! The non-Gaussianity threshold is further out but is hopefully achievable ! There is reason to hope the coming decades will be as interesting as the previous ones 12 ... is the angular power spectrum This matrix is available at the scale of this plot the unbinned model curve would be virtually indistinguishable from the binned curve except in the vicinity of the. .. “Inflation” Hot Big Bang - Radiation era Anything interesting here? BBN Decoupling Today Reheating Were fluctuations converted into curvature fluctuations at the beginning/during the hot big bang?... can be ignored when interpreting the results The 2nd column gives the medians and characteristic widths of the window functions as detailed in the text The error bars in the 3rd column include the

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