Theoretical and Observational Aspects of Coupled Dark Energy

Transcription

Theoretical and Observational
Aspects of Coupled Dark Energy
Andresa Campos, Rogerio Rosenfeld
IFT-Unesp, ICTP-SAIFR
XIX Swieca Summer School on Particles and Fields
February 10, 2017
Andresa Campos [email protected]
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I - Introduction
Standard Cosmological Model - ΛCDM
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I - Introduction
Several issues!!
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I - Introduction
Dark Matter
Several issues!!
Dark Energy
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I - Introduction
Dark Matter
Several issues!!
Dark Energy
Coupled Quintessence
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I - Introduction
Dark Matter
Coupled Quintessence
Several issues!!
Dark Energy
Phenomenological Fluids
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II - Coupled Dark Energy (Phen. Approach)
• Energy-momentum tensor:
ν
= Q(α)µ ,
∇ν T(α)µ
with the constraint
X
Q(α)µ = 0.
α
• The choice of Q(α)µ specifies the strength of the coupling.
Q = 3Hλρd .
λ: new parameter
Other choices can be made!!
ν
ν where u = (−a, 0, 0, 0) and w ≡ p /ρ .
= (ρα + pα )uµ uν + pα δµ
Recall T(α)µ
µ
α
α
α
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III - Background
Conservation equations
ρ̇d + 3Hρd (1 + wd ) = −3Hλρd
ρ̇c + 3Hρc = +3Hλρd
DM −→ DE
• λ > 0: DE −→ DM
• λ < 0:
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IV - Perturbations
Linear perturbations in synchronous gauge
δ̇c = −(kvc + ḣ/2) + 3Hλ(δd − δc )ρd /ρc ,
v̇c = −Hvc (1 + λρd /ρc ),
δ̇d = −(1 + w)(kvc + ḣ/2)
+ 3H[(w − c2e ) − 3H(c2e − c2a )(1 + w + λ)vd /k],
3H
δd
v̇d = −H(1 − 3c2e )vd +
(1 + c2e )λvd + kc2e
.
1+w
1+w
CAMB, CLASS, CMBFAST etc.
Andresa Campos [email protected]sp.br
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V - Modified CAMB
We use a modified version of CAMB† to solve these equations.
• Shift in the matterradiation equality;
• Change in location and
amplitude of the BAO;
• Change in velocity of
perturbation growth.
† Andre Costa, Xiao-Dong Xu, Bin Wang, and Elcio Abdalla.
(ArXiv:1605.04138)
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VI - Dark Energy Survey
Photometric Galaxy Survey
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High redshift
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High redshift
Poor redshift precision
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High redshift
Standard approach: split the data into
redshift bins and use ω(θ) or C` .
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High redshift
Standard approach: split the data into
redshift bins and use ω(θ) or C` .
C`,Limber =
Z
2
dzφ (z)P
` + 1/2
r(z)
!
1
r2 (z)
.
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VI - Angular Matter Power Spectrum
Angular Power Spectrum 0.45 ≤ z ≤0.55
103 `C`
101
w= -0.9999 λ=-0.03
w= -1.0000 λ=0.00
w= -1.0001 λ=0.03
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101
`
102
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VII - Fisher Information Matrix
Assuming a Gaussian likelihood, the Fisher matrix elements are given by
Fαβ =
X 1 ∂Xi ∂Xi
σi2 ∂θα ∂θβ
i
Xi
C`
θ
λ and w
λf id = 0 and wf id = −1.0001
The variance in the C` ’s can be estimated as σ`2 ≈
2 C`2
.
fsky (2` + 1)
For DES, fsky ∼ 1/8.
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VII - Fisher Information Matrix
Assuming a Gaussian likelihood, the Fisher matrix elements are given by
Fαβ =
Xi
X 1 ∂Xi ∂Xi
σi2 ∂θα ∂θβ
i
C`
θ
λ and w
λf id = 0 and wf id = −1.0001
The variance in the C` ’s can be estimated as σ`2 ≈
2 C`2
.
fsky (2` + 1)
For DES, fsky ∼ 1/8.
-0.94
-0.96
[F]−1 = C =
σλ2
σλ σw
σλ σw
2
σw
Preliminary results!
-0.98
-1.00
-1.02
-1.04
-1.06
-0.5
0.0
0.5
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Next
• All parameters
• Photo-z error
• Beyond Limber
• More redshift bins
• Redshift-space distortions
• Binning in `
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Next
• All parameters
• Photo-z error
• Beyond Limber
• Binning in `
Data from first year of observations of Dark Energy Survey
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Next
• All parameters
• Photo-z error
• Beyond Limber
• Binning in `
Data from first year of observations of Dark Energy Survey
Thank you!
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Theoretical and Observational Aspects of Coupled Dark Energy

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