PRE-SUSY Karlsruhe July 2007Rocky Kolb

The University of Chicago

Cosmology 101Cosmology 101

Rocky I: The Universe Observed

Rocky II: Dark Matter

Rocky III: Dark Energy

Dark Matter: 25%

Dark Energy (): 70%

Stars:0.5%

Free H & He:4%

Chemical Elements: (other than H & He)0.025%

Neutrinos: 0.47%

CDMCDM

Radiation: 0.005%

cmb

dynamics x-ray gaslensing

simulations

power spectrum

TOTAL (CMB) M B

MM

If We Could “See” Dark MatterIf We Could “See” Dark Matter

Navarro, et al.

Matter?Matter?

• Black holes

• Planets

• Dwarf starsbrown red white

• MOND (Modified Newtonian Dynamics)

• Fossil relic from the big bang (WIMP)

MOND Takes a BulletMOND Takes a Bullet

Dark Matter?Dark Matter?• neutrinos (hot dark matter)

• sterile neutrinos, gravitinos (warm dark matter)

• axions, axion clusters

• LKP (lightest Kaluza-Klein particle)

• supermassive wimpzillas

• solitons (Q-balls; B-balls; Odd-balls, Screw-balls….)

• LSP (neutralino, axino, …) (cold dark matter)

axions

axion clusters

6 40

8 25

10 eV (10 g)

10 M (10 g)

Mass range

Noninteracting: wimpzillas

Strongly interacting: B balls

Interaction strength range

10 WIMPlog GeVM

log 10

(/p

icob

arns

)

Particle Dark Matter CandidatesParticle Dark Matter CandidatesSUSYM GUTM PLANCKMPQf IH

coldthermalrelics w

imp

zilla

gravitino

axion

QCD

STERILEM

STRINGM

Other Scales::

TECHNICOLORM

EXTRA DIMENSIONSM

EWKM

WEAK" "

NeutrinosNeutrinos

• Neutrinos exist:

three active + sterile?

• Neutrinos have mass: Atmospheric ( eV) Solar ( eV)

• Not most of dark mattertoo hot!too light!

45 eVm

• Contribute to hot thermal relic:

Growth of small perturbationsGrowth of small perturbations

Today (13.78 Gyr AB)

• radiation and matter decoupled

•

•

5~ 10T T 6~ 10G G

Before recombination (380 kyr AB)

• radiation and matter coupled

•

•

5~ 10T T 5~ 10G G

AndreyKravtsov

The growth of cosmic seedsThe growth of cosmic seeds

100

My

r

1 G

yr

5 G

yr

tod

ay

The growth of cosmic seedsThe growth of cosmic seeds

Dissipative processesDissipative processes

1. Collisionless phase mixing – free streamingIf dark matter is relativistic or semi-relativistic particles can stream out of overdense regions and smooth out inhomogeneities. The faster the particle the longer its free-streaming length.

Quintessential example: eV-range neutrinos

Collisionless dampingCollisionless damping

CDM

HDM

Melchiorri, Dodelson, Serra, Slosar, 2006

meVAll: m eVWMAP: m eV

Collisional dampingCollisional damping

Dissipative processesDissipative processes

1. Collisionless phase mixing – free streamingIf dark matter is relativistic or semi-relativistic particles can stream out of overdense regions and smooth out inhomogeneities. The faster the particle the longer its free-streaming length.

Quintessential example: eV-range neutrinos

1. Collisional damping – Silk dampingAs baryons decouple from photons, the photon mean-free path becomes large. As photons escape from dense regions, they can drag baryons along, erasing baryon perturbations on small scales.

Baryon-photon fluid suffers damped oscillations.

The evolved spectrumThe evolved spectrum

Cold Thermal Relics*Cold Thermal Relics*

• Particle is stable (or at least has a lifetime greater than age of universe)

• There is no associated chemical potential (no asymmetry)

• Particle is in LTE at temperatures greater than its mass

• Particle remains in LTE until M T (cold)

• Particle annihilates with thermal-average cross section v

* An object of particular veneration.

Cold Thermal RelicsCold Thermal Relics

freeze out

actual

equilibrium

X

T/MX

1010

Rel

ativ

e ab

un

dan

ce

1510

2010

510

010

1 2 31 10 10 10

/e M T

Cold Thermal RelicsCold Thermal Relics

• Particle is stable (or at least has a lifetime greater than age of universe)

• There is no associated chemical potential (no asymmetry)

• Particle is in LTE at temperatures greater than its mass

• Particle remains in LTE until M T (cold)

• Particle annihilates with thermal-average cross section v (TM)n

• Freeze-out at

• Freeze-out abundance relative to entropy density (or photon density)

• Contributing to

01 lnF PlM T n MM

1

0

n

FX X

Pl

M Tn nM

s MM s

10

Cold Thermal RelicsCold Thermal Relics

freeze out

actual

equilibrium

X

T/MX

1010

Rel

ativ

e ab

un

dan

ce

1510

2010

510

010

1 2 31 10 10 10

/e M T

X A(independent of mass)

Cold Thermal RelicsCold Thermal Relics X X AA

X A

X X q q

X

X

q

q

X S

X q X q

X

q q

X

X P

q q X X Xq

q X

• Direct detection (S)

More than a dozen experiments

• Indirect detection (A)

Annihilation in sun, Earth, galaxy. . .

neutrinos, positrons,

antiprotons, rays, . . .

• Accelerator production (P)

Tevatron, LHC, ILC

Cold thermal relics (neutralino)Cold thermal relics (neutralino)

freeze out

actual

equilibrium

X

T/MX

1010R

elat

ive

abu

nd

ance

1510

2010

510

010

1 2 31 10 10 10

/e M T

Cold Thermal RelicsCold Thermal Relics

• s-wave or p-wave?• annihilation or scattering cross section?• co-annihilation?• sub-leading dependence on mass, g*, etc.

Not quite so clean:

Indirect DetectionIndirect Detection

• Neutrinos from the sun or Earth

• Anomalous cosmic rays and rays from galactic halo(s)

• Neutrinos, rays , radio waves from our galactic center

• Role of halo substructure [rate (density)2]

Galactic center: spike cusp, ???Black hole in the galactic center

Small-Scale StructureSmall-Scale Structure

Moore et al.

Small-Scale Structure Small-Scale Structure

Moore et al.

14Cluster 5 10

2 Mpc

M

12Galaxy 2 10

300 kpc

M

Nonbaryonic Dark MatterNonbaryonic Dark Matter

Familiar candidate: a neutralino

“a simple, elegant, compelling explanation for a complex physical phenomenon”

“For every complex natural phenomenon there is a simple, elegant, compelling, wrong explanation.” - Tommy Gold

Kaluza-Klein ParticlesKaluza-Klein ParticlesKolb & Slansky (84); Servant & Tait (02); Cheng, Feng & Matchev (02)

2 2 2 2 2 25 5

2 2 2 2 2

n n

E p p p n R

p M M n R

Quantized Kaluza-Klein excitations

Conservation of momentum conservation of KK mode number

First excited mode (n=1) stable, mass R-1

First excited mode (n=1) stable, mass R-1

needchiral

fermions

KK quantum number KK parity

X

X1 12S S Z

R 1 4S M3 space dimensions

Kaluza-Klein ParticlesKaluza-Klein Particles

• LKP = KK photon

• Looks like SUSY

• Beware KK graviton

• Direct detection

• Indirect detection

Kolb, Servant & Tait

Bertrone, Servant, Sigl

Servant & TaitCheng, Feng & Matchev

Cheng, Matchev & Schmaltz

Cheng, Matchev & Schmaltz

1 500 GeVR

Sterile Neutrinos & GravitinosSterile Neutrinos & Gravitinos

• weaker interactions• decouple earlier• diluted more• can have larger mass• smaller velocity• “warm”• satellite & cusp problem?

Particle models with sterile neutrinos or gravitinos in desired mass range are “unfashionable.”

Warm Dark Matter

Axion Dark MatterAxion Dark Matter

. . . about to be ruled out or closing in on detection

• Pseudo-Nambu-Goldstone boson

• Axion mass:

• Pseudoscalar

• Couples to two photons through the anomaly

• Very weakly interacting with matter

• Origin of axions phase transition

decay of axion strings

2 710 GeV1 eV a

PQ PQ

mf f

BallsBalls

• Q-balls (non-topological solitons): S. Coleman; T.D. Lee

Scalar field withconserved global charge “Q”

Ground state is a Q-ball, lump of coherentscalar condensate

3 4 :E Q can’t decay to Q free particles

• Q-ball production and evolution:

Solitogenesis Frieman, Gelmini, Gleiser & Kolb

Solitosynthesis Frieman, Olinto, Gleiser & Alcock; Greist & Kolb

Statistical fluctuations Greist, Kolb & Masssarotti

Condensate fragmentation Kusenko & Shaposhnikov

BallsBalls

• Q-balls exist in MSSM scalars = squarks & sleptons

• Fragmentation of Affleck-Dine condensate

• Relates DM to B

Kusenko, Shapashnikov & Tinyakov

3 4 12(1 TeV) stable for 10BM B B Kusenko & Shapashnikov

3 2410 g 10BM B

Affleck-Dine condensate

related!

Baryon asymmetry B-ball dark matter

Nonthermal Dark MatterNonthermal Dark Matter(Supermassive Relics)(Supermassive Relics)

Production Mechanisms:

• Bubble collisions Chung, Kolb, Riotto

• Preheating Chung

• Reheating Chung, Kolb, Riotto

• Gravitational Chung, Kolb, Riotto; Kuzmin & Tkachev

new application: dark matter(Chung, Kolb, & Riotto; Kuzmin & Tkachev)

• require (super)massive particle “X”

• stable (or at least long lived)• initial inflationary era followed by radiation/matter

Arnowit, Birrell, Bunch, Davies, Deser, Ford, Fulling, Grib, Hu, Kofman, Lukash, Mostepanenko, Page, Parker, Starobinski, Unruh, Vilenkin, Wald, Zel’dovich,…

first application:

(Guth & Pi; Starobinski; Bardeen, Steinhardt, & Turner; Hawking; Rubakov; Fabbi & Pollack; Allen)

Expanding Universe Particle CreationExpanding Universe Particle Creation

density perturbations from inflation

gravitational waves from inflation

It’s not a bug, it’s a feature!

Chung, Kolb& Riotto; Kuzmin & Tkachev)

GeV10 to101for1 1510INFLATON XXX MMM

INFLATONMM X

chaoticinflation

Particle ProductionParticle Production

Inflaton mass (in principle measurable from gravitational wave background, guess ) may signal a new mass scale in nature.

Other particles may exist with mass comparable to the

inflaton mass.

Conserved quantum numbers may render the particle stable.

GeV10 12

Superheavy ParticlesSuperheavy Particles

• supermassive: GeV (~ 1012 GeV ?)

• abundance may depend only on mass

• abundance may be independent of interactions

– sterile?

– electrically charged?

– strong interactions?

– weak interactions?

• unstable (lifetime > age of the universe)?

Wimpzilla Characteristics:Wimpzilla Characteristics:

WIMPZILLA footprints:WIMPZILLA footprints:

Isocurvature modes: CMB, Large-scale structure

Decay: Ultra High Energy Cosmic Rays

Annihilate: Galactic Center, Sun

Direct Detection: Bulk, Underground Searches

Cold Dark Matter: 25%

Dark Energy (): 70%

Stars:0.5%

Free H & He:4%

Chemical Elements: (other than H & He)0.025%

Neutrinos: 0.47%

CDMCDM

Radiation: 0.005%

PRE-SUSY Karlsruhe July 2007Rocky Kolb

The University of Chicago

Cosmology 101Cosmology 101

Rocky I: The Universe Observed

Rocky II: Dark Matter

Rocky III: Dark Energy