Circular Polarization of Gravitational Waves in String Cosmology
Cosmology in LARGE volume string models
description
Transcript of Cosmology in LARGE volume string models
Cosmology in LARGE volume string models
Tetsutaro Higaki
arXiv: 1208.3563 published in JHEP 1211 (2012) 125 with Fuminobu Takahashi at Tohoku U.
See also arXiv: 1208.3562 by Cicoli, Conlon and Quevedo
01/29/2013@Osaka U.
Production of a hot dark mattervia LARGE extra dimensions.
1. Motivation: Exploring the origin of the Universe.
1. Introduction
The present universe consists of
Dark matter and dark energy clearly requirenew physics beyond the Standard Model (SM).
What is the Universe made of?
Past and now of the Universe
In the early Universe• Baryons• Dark matter (Cold DM)• Photons• Neutrinosdominated.
Past and now of the Universe
In the early Universe• Baryons• Dark matter (Cold DM)• Photons• Neutrinos + Dark radiationdominated.
Sterile 4th neutrino-like(A part of hot dark matter)
My motivation
Dark radiationNeff ~ 4
||A probe of high energy physics!?
The Standard
Model
Moduli& Hidden
sectors
E.g. Gravity
Anomaly cancellation condition
Overview of string-theory-models
Hidden sectors appear naturallythrough stringy compactifications!
Supergravity models on aLARGE Swiss-cheese Calabi-Yau (CY)
SM
Main characters in 4D SUGRA
1. Size of CY3 2.Higgs 3. Axion (Ex-dim.) (DR)
4. Wino (CDM)
Contents
1. Introduction: Motivations and short summary
2. Observations and dark Radiation
3. LARGE volume scenario (LVS)
4. Dark radiation and dark matter from the modulus decay
5. Conclusion and open questions
2. Observations of dark radiation (a hot DM)
Dark radiation (DR)
• 4th neutrino-like component in cosmic ν background
Ultralight mass: MDR m≦ ν 0.1 eV≦Almost no interaction: Gravity or…
How can we detect the presence indirectly?
In radiation-dominated era with T 1MeV ≦
DR
DR and expansion of the universe
The expansion rate gets increased by ΔNeff.
H: Expansion rate (Hubble parameter)
The Friedman equation in rad. era
DR and expansion of the universe
4He abundaceis sensitive to the expansion rate H at BBN era ~ 1 sec.
Cosmic Microwave Background (CMB)is sensitive to H at~ 380,000 year.
Mild DR evidence
Cyburt, Fields, Olive (2008)
Cyburt, Fields, Olive (2008)
HII region(H+, He*,O*,…)
CMB
ΔT/T0 map on the sky sphere, where T0 = 2.73K.
WMAP 9-year
CMB
Fourier form of ΔT/T0 map on the sky sphere, where T0 = 2.73K.
WMAP 9-year, 1212.5226
South Pole Telescope (SPT)
Wilkinson Microwave Anisotropy Probe(WMAP)
Atacama Cosmology Telescope (ACT) in Chili
Recent other CMB data
• WMAP 9-year, 1212.5226:
• Atacama Cosmology Telescope (ACT), 1301.0824:
Recent other CMB data
• WMAP 9-year, 1212.5226:
• Atacama Cosmology Telescope (ACT), 1301.0824:
– Fewer # of data– Different frequency in CMB
Note: Tension between BAO and H0.
Wrong!!;will be
modified.
Adoption of SPT result
So, both 4He abundance and CMB mildly prefer the presence of extra radiation:
in 4D N=1 supergravity (SUGRA) framework.
For confirmation of dark radiation
WMAP 9-year, 1212.5226Needs data from the Planck.
3. LARGE volume scenario (LVS):IIB orientifold supergravities in flux vacua
Motivation for string theory
Unified theory including quantum gravity!
Closed string= Gravity
Open string= Gauge
D-brane
Open stringbetween branes
= Matter
nucleons
Extra dimensions and SUSY
• The quantum gravity theory requiresextra 6 dimensions and supersymmetry (SUSY).
M4 ×
4 + 6 = 10
The Standard
Model
Moduli& Hidden
sectors
E.g. Gravity
Anomaly cancellation condition
Phenomenological motivation
Hidden sectors appear naturallythrough stringy compactifications!
Moduli in a Calabi-Yau space
SUSY-preservedcompactification
4-cycle size: T (Kähler moduli)
3-cycle size: U (Complex structure moduli)
+ String Dilaton: S
Moduli in a Calabi-Yau space
SUSY-preservedcompactification
Why moduli and axions?
1. Ubiquitous in string vacua.
2. VEVs = physical constants:• Size of extra dimension;
• Gauge/Yukawa couplings,
• SUSY-breaking parameters.
Moduli ~ gauge couplings
(Ex) (4+n) dim. gauge theory on a brane (M4×Σn):
Moduli ~ gauge couplings
(Ex) (4+n) dim. gauge theory on a brane (M4×Σn):
Moduli field φ : Volume of a cycle
Moduli ~ gauge couplings
(Ex) (4+n) dim. gauge theory on a brane (M4×Σn):
Moduli field φ : Volume of a cycle
An extra 6 dimension spacecan have many Σn .
↓ Many moduli
Axions ~ θ-term
(Ex) (4+n) dim. gauge theory on a brane (M4×Σn):
Axions ~ θ-term
(Ex) (4+n) dim. gauge theory on a brane (M4×Σn):
Axion field a: Integrand of tensor field Cn (NSNS, RR)
Axions ~ θ-term
(Ex) (4+n) dim. gauge theory on a brane (M4×Σn):
An extra 6 dimension spacecan have many Σn .
↓ Many axions
Axion field a: Integrand of tensor field Cn (NSNS, RR)
What are their masses?
What are their VEVs?(= couplings etc.)
Moduli/axion stabilization
Flux compactifications with O-planes and D-branes
Moduli/axion stabilization
• Finding a vacuum of moduli in a string model
Example of potential for moduli
Ultralight axion(s)
• In a LARGE volume limit of compact space,axion will get ultralight thanks to a residual gauge symmetries on Cn in 10D:
• The axions originate from gravity Cn (NSNS or RR-field).
Model:LARGE volume scenario
(LVS)
V. Balasubramanian, P. Berglund, J. P. Conlon and F. Quevedo.(2005);
R. Blumenhagen , J. P. Conlon , S. Krippendorf, S. Moster and F. Quevedo.(2009)
Cartoon of LVS models:Swiss cheese Calabi-Yaus
Note: 418 such explicit CY models; a single hole model J. Gray, Y.H. He, V. Jejjala, B. Jurke, B. Nelsond and J. Simon (2012)
Intersection # among 2cycles is important.
Note: 418 such explicit CY models; a single hole model J. Gray, Y.H. He, V. Jejjala, B. Jurke, B. Nelsond and J. Simon (2012)
Instantons3-form
FluxModuli stabilization
forvolume, holes, shapes.
Cartoon of LVS models:Swiss cheese Calabi-Yaus
Note: 418 such explicit CY models; a single hole model J. Gray, Y.H. He, V. Jejjala, B. Jurke, B. Nelsond and J. Simon (2012)
Local model:MSSM + U(1)Aon D3-branes.
It is on a singularity,which is stabilized by FI=0.
QL
QR
LL
eR
U(2)
U(3)
U(1)
U(1)
Cartoon of LVS models:Swiss cheese Calabi-Yaus
Matter content of the MSSM(Minimal Supersymmetric Standard Model)
R-parity(Superpartner)= -1 R-parity(SM-particles)= +1
Model details
Notation for 4D N=1 SUGRA
Lagrangian:
K : Kähler potential, W: Superpotential
f : gauge coupling function
,
Volume moduli stabilization in LVS
Tb: Overall volume + DRTs: Hole volume + heavy axion
Scalar potential
Other moduli can be irrelevant in this analysis.
as=2πτs = Re(Ts)
Vpot
Exponentially LARGE volume CY
LARGE moduli VEV:
ξ =O(1) χ(CY) : A choice of Swiss cheese CY.∝gs =O(0.1) : A choice of quantized flux.
Note: SUSY-breaking AdS; needs ΔVpot ~ Vol(CY)-3 for dS/Mink.
• Masses: Gravitino and the lightest modulus
• SUSY-breaking parameters on D3-branes (local):
CY volume controls everything
Mass scales
•Overall volume: ~ 106 GeV
•Holes (volume): ~ 1012 GeV
•Shape: ~ 1011 GeV ~ gravitino mass
•Singularity: ~ 1015 GeV ~ string scale
for Volume (CY) = O(107) in string unit;1/R= O(1013) GeV
Mass scales
•Overall volume: ~ 106 GeV
•Holes (volume): ~ 1012 GeV
•Shape: ~ 1011 GeV ~ gravitino mass
•Singularity: ~ 1015 GeV ~ string scale
for Volume (CY) = O(107) in string unit;1/R= O(1013) GeV
Instantons(ED3-branes)3-form
Flux
A dark radiation candidate in LVS
TH, Takahashi;Cicoli, Conlon, Quevedo(2012)
ab:= Im(Tb): Axion as dark radiation
• stays ultralight even if we have
where Re(Tb)= Vol(CY)2/3 = 105 >>1.
• is only gravitationally interacting.
5. Dark radiation and dark matter from the modulus decay
TH, Takahashi
See alsoCicoli, Conlon, Quevedo
Why modulus decay?
• Answer: It reheats the universe, producing DM and DR.
: Canonically-normalized fluctuation of Tb
Moduli problem in LVS
• Before inflation, modulus will be in the vacuum
• Inflation produces additional potential for φ
Moduli problem in LVS
• During inflation, modulus is sitting false vacuum
Moduli problem in LVS
• During inflation, modulus is sitting false vacuum
Moduli problem in LVS
• For Hinf > mφ1 decompactification occurs.
Moduli problem in LVS
• For Hinf > mφ1 decompactification occurs.
is required.
Moduli problem in LVS
• At the end of inflation, inflaton contribution will vanish.
Moduli problem for Hinf m≦ φ1 TH, Kamada, Takahashi
• At the end of inflation, modulus starts to oscillate
for mInflaton > mφ1.
Amplitude:
Moduli problem for Hinf m≦ φ1 TH, Kamada, Takahashi
• At the end of inflation, modulus starts to oscillate
for mInflaton > mφ1.
Energy (matter-like):
Moduli problem for Hinf m≦ φ1 TH, Kamada, Takahashi
from inflaton decay
Moduli decay: New radiation
at H = Γφ1 At the end of inflation,Modulus starts to oscillate
Hinf m≦ φ1 < minflaton
Modulus decay in LVS and No-scale
• z: Coefficient for higgsino mass (μ-term)
• V= Re(Tb)3/2 : Swiss-cheese CY volume
• Wmatter: Yukawa-terms for matter Qi
b b
Modulus decay into Higgs and axions
• Decay width of modulus φ1
• Reheating temperature and branching to DR
nH : The total number of Higgs multipletsz2 n⇔ H
• Decay width of modulus φ1 with z=1
• Partial decay width to DR with z=1
If there are additional Higgses,…
Dark radiation vs z (nH=1)
mφ ~ V-3/2
ΔNeff obs ~ 1
Gauge-Higgs Unification in SUSY?
We have z ~ 1 (tanβ ~ 1),
if K ~ |Hu + Hd†|2 with a shift symmetry
Hu → Hu + ic, Hd → Hd + ic.
Hebecker et al.
Non-chiral Higgs pair
Dark matter: Wino(With assumed R-parity)
DM: Motivation for SUSY
R-parity(Superpartner)= -1 R-parity(SM-particles)= +1
DM = Wino is assumed
Modulus decay into Wino DM
φ1
Hu
Hd
Br = O(1)
Modulus decay into Wino DM
Hu
Hd
Br = O(0.01)~ 1/Nchannel
for m0 = 1/V2 = O(10) TeV,
μ ~ M1/2 = 1/log(V)V2 = O(1) TeV.
Wino DM pair annihilation
These process hardly depends on the branching fraction.
Wino abundance Ωwinoh2 vs z
(ΩCDMh2)obs ~ 0.1
For z ~ 1.5, ΔNeff ~ 1
mWino ~ 500GeV
Moroi, Nakayama (2011)
Constraint on Wino-like DM massmWino 500 GeV!≧
DR and DM from modulus decay
Higgs from φ1 DR (no-scale), DM (the decay)
• For z ~ 1.5 or 2-3 ×(Hu, Hd) with each z = 1, DR can be explained.
• For mWino ~ 500 GeV, DR and DM are explained.
• If higgsino is DM, they are too many produced.
6.Conclusion and open questions
Production of a hot dark mattervia LARGE extra dimensions.
LARGE Swiss-cheese CY in the cosmos
LARGE Volume modulus : φ
The φ decay: φ→ Higgs + axions + Wino
in 4D N=1 supergravity (SUGRA) framework.
Summary of cosmology
The φ decay: φ→ Higgs + axions + Wino
• reheats the universe at Tdec ~ 1GeV.
in 4D N=1 supergravity (SUGRA) framework.
Summary of cosmology
The φ decay: φ→ Higgs + axions + Wino
• reheats the universe at Tdec ~ 1GeV.
• also produces DR of string-theoretic axions. LARGE volume CY: Ultralight axion and No-scale
in 4D N=1 supergravity (SUGRA) framework.
Summary of cosmology
The φ decay: φ→ Higgs + axions + Wino
• reheats the universe at Tdec ~ 1GeV.
• also produces DR of string-theoretic axions. LARGE volume CY: Ultralight axion and No-scale
• also produces DM of Winos (with assumed R-parity).
in 4D N=1 supergravity (SUGRA) framework.
Summary of cosmology
in 4D N=1 supergravity (SUGRA) framework.
For confirmation of dark radiation
WMAP 9-year, 1212.5226Needs data from the Planck.
Many open questions
Concrete stringy realization?
Vacuum selection rule?
Reconsideration of “naturalness”?:Mnew phys >> TeV ?
Swiss-cheese can be useful not only for “food life”
but also for “our lives” in the cosmos.
Thank you!
Backup
100points of HII regions(Ionized hydrogen: T ~ 104K)
Yp vs Oxygen
Spectraanalysis
Steigman (2012)
(Time?: O needs time for production)
Tension in H0 observations
WMAP 9-year, 1212.5226