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The HORIZON Quintessential Simulations. Füzfa 1,2 , J.-M. Alimi 2 , V. Boucher 3 , F. Roy 2. 1 Chargé de recherches F.N.R.S., University of Namur, Belgium 2 LUTh – Observatoire de Paris 3 Center for Particle Physics Phenomenology (CP3), University of Louvain, Belgium.
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The HORIZON Quintessential Simulations Füzfa1,2, J.-M. Alimi2, V. Boucher3, F. Roy2 1Chargé de recherchesF.N.R.S., University of Namur, Belgium 2LUTh – Observatoire de Paris 3Center for Particle Physics Phenomenology (CP3), University of Louvain, Belgium
What is the nature of Dark Energy (DE)? • Quintessence • Dynamical DE : rQvaries with time • Inhomogeneous DE : df(k,t)≠0 • Possible direct interactions with matter (not purely gravitational): • DE-DM couplings (see PSC talk) • DE-Baryons couplings • Violation of the equivalence principle! Casimir effect (Vacuum Fluctuations) • Cosmological Constant • Fine-tuning and coincidence! • Frozen DE : rL=ct for all time • Homogeneous DE • No direct interactions with matter (purely gravitational) Negative pressures! Evacuum Evacuum↑↑↑ Evacuum↑ Cosmic expansion produces more vacuum energy Cosmic acceleration!
Dark energy and structure formation Theoretical approaches to DE (quintessence, scalar-tensor gravity, …) → a(t),H(t), f(t), G(t), D+(a) … ↓ Constraints from recent cosmic expansion (Hubble diagrams of SNe Ia)→ Wm,WQ ↓ Constraints from CMB angular fluctuations → Wb,WCDM, s8lin ↓ Linear Matter Power Spectrum at z=0 and Linear growing modes D+(a) → initial conditions at zstart ↓ N-body simulations (CDM only, here) with corresponding H(a) ↓ Observational constraints : weak-lensing, baryon acoustic oscillation, …
A) Considered theoretical models • Cosmological constant LCDM • Quintessence scenari: • Ratra-Peebles potential (SUSY breaking, backreactions, …) RPCDM • Sugra potential (radiative correction of RPCDM at E~mPl) SUCDM
B) Constraints from Hubble diagrams Hubble Parameter Equation of State SNe Ia redshift range z<1.1 • Determination of Wm and W(L,Q) from SNLS 1st year data set • Degeneracies of the models (≈c²=116 for 115 data) • LCDM vs QCDM’s : frozen vs dynamical DE • RPCDM vs SUCDM: LSS tests of varying w(z) CMB astart
C) Constraints from CMB anisotropies • Modification of CAMB code (in collaboration with V. Boucher, CP3): • Cosmic expansion with quintessence (zeroth order) • first order perturbations of the quintessence fluid (large-scales inhomogeneities) • minimal-coupling • Results: Angular Power Spectrum Linear Matter Power Spectrum DE Clusterization Different Wb/WCDM Different s8
D) Cosmological parameters table H0=73 km/s/Mpc ; WL,Q=1-Wm astart=0.0403 ; ns=0.951
E) N-body quintessential simulations • Quintessence and cosmological constant DE models are almost equivalent to explain CMB and SNe Ia • LSS can settle the DE debate? • New constraints on DE from LSS • Criteria for detecting w(z) at z>>1 • Predictions on LSS from alternatives to L • Horizon Quintessential Simulations (LCDM, RPCDM, SUCDM): • L=500h-1Mpc ; Npart=Ncells=10243 ; CDM only (Particle-Mesh code) • 65 snapshots (26+1) between as=0.04 and a0=1 • 3x1.6 Tb data • 3 x 3000 h on Zahir (IDRIS) with 32 Procs, 3.7Gb RAM/Procs (300 time steps) • Present storage: gaya.idris.fr => /fuzfa • At disposal for the collaboration at horizon.obspm.fr:/storage
LCDM @z=0
RPCDM @z=0
SUCDM @z=0
LCDM @z=0
RPCDM @z=0
SUCDM @z=0
Conclusions • Tools developped: • DarkCosmos (homogeneous cosmological models with quintessence ; adequacy with Hubble diagrams of type Ia SNe and linear growing modes) • CAMB+Q : CMB code with zero and first order behavior of quintessence • Mpgrafic-Q : initial conditions from a CAMB generated power spectrum • PM+Q : N-body DM only Particle-Mesh code with quintessence (normalization and cosmic expansion) • Interesting analysis of quintessential simulations (HORIZON Collaboration): • Effect of slope of power spectrum at large-scales (DE clusterization): 3D skeleton • Baryon wiggles, correlation function (baryon acoustic oscillation) and non-linear s8 • DM Clusters properties (mass function, velocity distribution, …) • Semi-analytical approaches to populate with virtual objects • Quintessential simulations for weak-lensing Toward new constraints on DE from LSS?