Anisotropies of Cosmic - PowerPoint Presentation

Slide1

Anisotropies of Cosmic Microwave Backgroundand Its Polarization

A New & Ultimate Tool for Cosmology and Particle Physics

Naoshi SugiyamaNagoya University

Taup2007@SendaiSlide2

Cosmic Microwave BackgroundDirect Evidence of Big BangFound in 1964 by Penzias & WilsonVery Precise Black Body by COBE (J.Mather)

John Mather

Arno Allan Penzias

Robert Woodrow Wilson Slide3

Frequency

４００

σ！

Perfect Black Body

NASA/GSFC

提供Slide4

Temperature Fluctuations of Cosmic Microwave BackgroundFound by COBE/DMR (G.Smoot), measured in detail by WMAPStructure at 380,000 yrs (z=1100)

Recombination epoch of Hydrogen atomsMissing Link between Inflation (10-36s) and Present (13.7 Billion yrs)Ideal Probe of Cosmological Parameters Typical Sizes of Fluctuation Patters are Theoretically Known as Functions of

Various Cosmological Parameters Slide5

COBE & WMAP

George SmootSlide6

Physical Processes to Induce CMB FluctuationsOriginated from Quantum Fluctuations at the Inflation EpochAlmost Scale Free (Invariant Spectrum):Dominated by Gravitational Redshift (Sachs-Wolfe effect) on Large ScalesAcoustic Oscillations Play an Important Role on Intermediate ScalesDiffusion Damping works on Small Scales

Statistical Quantity: Angular Power Spectrum ClSlide7

10°

1°10min

COBELarge

Small

Gravitaional Redshift

(Sachs-Wolfe)

Acoustic OscillationsDiffusion dampingCOBEWMAPSlide8

What control CMB AnisotropiesSound Velocity at RecombinationBaryon Density: Bh2Horizon Size at RecombinationMatter Density:

Mh2Radiative Transfer between Recombination and PresentSpace Curvature: 

KInitial Condition of FluctuationsIf Power law, its index n (P(k)kn)Slide9



M

h

2

small

large

MSlide10



B

h

2

small

large

largesmall

MSlide11

Open:

Concave lens space

Image becomes smallShifts to larger lSlide12

Negative curvatureSlide13

ObservationsCOBEClearly see large scale (low l ) tailangular resolution was too bad to resolve peaks

Balloon borne/Grand Base experimentsBoomerang, MAXMA, CBI, Saskatoon, Python, OVRO, etc See some evidence of the first peak, even in Last Century!WMAP Slide14

CMB observations by 1999Slide15

1

st yr

3 yrWMAP ObservationSlide16

WMAP Temperature Power Spectrum Clear existence of large scale Plateau Clear existence of Acoustic Peaks (upto

2nd or 3rd ) 3rd Peak has been seen by 3 yr data

Consistent with Inflation and Cold Dark Matter Paradigm

One Puzzle:

Unexpectedly low Quadrupole (

l

=2)Slide17

Measurements of Cosmological Parameters by WMAPBh2 =0.022290.00073 (3% error!)Mh

2 =0.128 0.008K=0.0140.017 (with H=728km/s/Mpc)

n=0.958 0.016

Baryon 4%

Dark Matter

20%

Dark Energy

76

%

Spergel

et al.

WMAP 3yr aloneSlide18

Finally Cosmologists Have the “Standard Model!”But…76% of total energy/density is unknown: Dark Energy20% of total energy/density is unknown: Dark Matter

Dark Energy is perhaps a final piece of the puzzle for cosmology equivalent to Higgs for particle physics Slide19

Dark EnergyHow do we determine =0.76? Subtraction!:

=

1- M - K

Q: Can CMB provide a direct probe of

Dark Energy?Slide20

Dark EnergyCMB can be a unique probe of dark energyTemperature Fluctuations are generated by the growth (decay) of the Large Scale Structure (z~1)Integrated Sachs-Wolfe Effect



1



2

Photon gets blue

Shift due to decay

E=|



1

-



2

|

Gravitational Potential of Structure

decays due to Dark EnergySlide21
Slide22
Slide23

Various Samples of CMB-LSS Cross-Correlation as a function of redshift

Measure w!

w=-0.5w=-1w=-2

Less

Than

10minSlide24

What else can we learn about fundamental physics from WMAP or future Experiments?Properties of NeutrinosNumbers of NeutrinosMasses of NeutrinosFundamental Physical ConstantsFine Structure ConstantGravitational ConstantSlide25

Constraints on Neutrino PropertiesChange Neff or m modifies the peak heights and locations of CMB spectrum.

Neutrino Numbers Neff and mass m Slide26

Measure the family number at

z

=1000CMB Angular Power SpectrumTheoretical Prediction Slide27

P. Serpico et al., (2004)

A. Cuoco et al., (2004)

P. Crotty et al., (2003)S. Hannestad, (2003)V. Barger et al.,

(2003)

R. Cyburt

et al.

(2005)E. Pierpaoli (2003)Unfortunately, difficult to set constraints on Neff by CMB alone: Need to combine with other dataBBN: Big Bang NucleothynthesisLSS: Large Scale StructureHST: Hubble constant from Hubble Space TelescopeSlide28

For Neutrino Mass, CMB with Large Scale Structure Data provide stringent limit since Neutrino Components prevent galaxy scale structure to be formed due to their kinetic energySlide29

Cold Dark Matter

Neutrino as Dark Matter(Hot Dark Matter)

Numerical SimulationSlide30
Slide31

Constraints on m and NeffWMAP 3yr Data paper by

Spergel et al.

LessThan

10minSlide32

Constraints on Fundamental Physical ConstantsThere are debates whether one has seen variation of  in QSO absorption linesTime variation of  affects on recombination process and scattering between CMB photons and electrons

WMAP 3yr data set: -0.039</<0.010 (by P.Stefanescu

2007)Fine Structure Constant Slide33

G can couple with Scalar Field (c.f. Super String motivated theory)Alternative Gravity theory: Brans-Dicke /Scalar-Tensor ThoeryG  1/

(scalar filed)G may be smaller in the early epochWMAP data set constrain: |G/G|<0.05 (2) (

Nagata, Chiba, N.S.)Gravitational Constant GSlide34

Scattering off electrons & CMB

quadrupole anisotropies produce linear polarizationPolarizationSlide35

Same

Flux

Same Flux

Electron

No-Preferred Direction

UnPolarized

Homogeneously Distributed Photons

Incoming

Electro-Magnetic

Field

scatteringSlide36

Strong

Flux

Weak Flux

Electron

Preferred Direction

Polarized

Photon Distributions with the Quadrupole Pattern

Incoming

Electro-Magnetic

Field

scatteringSlide37

Why is Polarization Important? Provide information of last scattering of photonsReionization of the Universe due to First Stars

Better estimation for Cosmological ParametersSensitive to Gravity Wave (Tensor Mode Fluctuations) Slide38

Two Independent ModesE-mode (Electronic), DivergenceDensity Fluctuations associated to Structure formation induce only this mode B-mode (Magnetic), RotationVector (rotational ) Fluctuations: decaying modeTensor (Gravitational Wave) Fluctuations

B-mode polarization is a unique probe of Gravitational Wave generated during Inflation

c.f. No way to separate two modes in Temperature Fluctuations Slide39

2 independent parity modes

E-mode

B-modeSeljakSlide40

E-modeSeljak

Scalar Perturbations only produce E-modeSlide41

B-modeTensor perturbations produce both E- and B- modesSlide42

Scalar ComponentSlide43

Hu & WhiteTensor ComponentSlide44

We can Prove Inflation from B-mode PolarizationConsistency RelationnT: Tensor Power Law IndexAT: Tensor AmplitudeAS

: Scalar AmplitudeIf we can find B-mode, we can measure tensor spectrum (nT & AT), and test consistency relationSlide45

ObservationsFirst Detection of E-mode Polarization was from DESI experiments (J.Carlstrom’s group)Boomerang Experiment (Balloon at Antarctica) WMAP made clear detection of E-mode polarization in the all sky map (

3yr data)Very difficult to detect since typically amplitude of polarization is factor 10 smaller than temperature fluctuationsSlide46
Slide47

TemperatureTemperature-E-mode

E-mode

B-mode(upper bound)Slide48

Polarization for WMAP is Temperature Fluctuations for COBE anyway, detect (E-mode)!But only upper bound for B-mode PolarizationSlide49

Ongoing, Forthcoming ExperimentsPLANCK is coming soon:More Frequency Coverage Better Angular ResolutionOther Experiments

Ongoing Ground-based:CAPMAP, CBI, DASI, KuPID

, PolatronUpcoming Ground-based:AMiBA, BICEP,

PolarBear

, QUEST,

CLOVER

Balloon:Archeops, BOOMERanG, MAXIPOLSpace:Inflation ProbeSlide50

Polarization is the next target after Temperature FluctuationsSlide51

It must be a Hat!Slide52
Slide53

Temperature

Power Spectrum

Polarization

Power SpectrumSlide54

Temperature

Power Spectrum

Polarization

Power Spectrum

?

?

Dark Matter, Dark Energy

Gravity Wave

“What is essential is invisible to the eye.” Slide55

First Order Effect

Liu et al. ApJ 561 (2001)ReionizationSlide56

E-mode PolarizationScalar PerturbationsTensor PerturbationsReionizationB-mode PolarizationTensor PerturbationsReionizationGravitational Lensing

from E-modeSlide57

Oxley et al. astroph/0501111Slide58

COBE

Power

Spectrum Cl: two dimensional power spectrum l=/

multipole

COBE:

l

< 20 (7 degree)WMAP: l < 800 gravitational redshift on large scale (Sachs-Wolfe) acoustic oscillations on intermediate scale diffusion damping on small scale (Silk damping) Different Physical Processes on different scalesSlide59
Slide60

Present Density Parameter Change the matter-radiation ratio near the recombination epoch, if m ~ a few eVConstraints from Cosmic Microwave Background

Neutrino Components prevent galaxy scale structure to be formed due to their kinetic energyConstraints from Large Scale Structure

Neutrino Mass mSlide61

 = -0.72±0.1810-5

0.5 < z < 3.5QSO absorption line

Webb et al.Slide62

Influence on CMBThomson Scattering: d/dtx

eneT

: optical depth, xe: ionization fraction ne: total electron density, 

T

: cross section

Slide63

If  is changed1) T2

is changed2) Temperature dependence of x

e i.e., temperature dependence of recombination preocess is modifiedFor example, 13.6eV = 2me

c

2

/2

is changed!If  was smaller, recombination became laterIf =±5%, z~100Slide64

=0.05

=-0.05Flat,

M=0.3, h=0.65, Bh2=0.019Ionization fractionSlide65

Temperature Fluctuation

Peaks shift to smaller l for smaller since the Universe was larger at recombination

=0.05

=-0.05Slide66

-0.039<Δα<0.010,

P. Stefanescu (2007)Slide67

Varying G and CMB anisotropies

Brans-Dicke / Scalar-Tensor TheoryG  1/

 (scalar filed) : G may be smaller in the early epoch

BUT, it’s not necessarily the case

in the early universe

Stringent Constraint from Solar-system: must be very close to General RelativitySlide68

G0

/GSlide69

If G was larger in the early universe, the horizon scale became smaller c/H = c(3/8G)

Peaks shift to larger lSlide70

Nagata, Chiba, N.S.

larger GSlide71
Slide72

We have hope to determine cosmological parameters together with the values of fundamental quantities,

i.e., , G

at the recombination epoch by measuring CMB anisotropies Slide73