cosmology and cosmic structures antonaldo diaferio dipartimento di fisica generale università degli...
TRANSCRIPT
![Page 1: COSMOLOGY AND COSMIC STRUCTURES Antonaldo Diaferio Dipartimento di Fisica Generale Università degli Studi di Torino Torino, 8 aprile 2008 Current collaborators:](https://reader036.vdocuments.us/reader036/viewer/2022062421/56649d0c5503460f949e0f35/html5/thumbnails/1.jpg)
COSMOLOGY AND
COSMIC STRUCTURES
Antonaldo DiaferioDipartimento di Fisica GeneraleUniversità degli Studi di Torino
Torino, 8 aprile 2008
Current collaborators:
Margaret J. Geller & Co. – Harvard-Smithsonian Center for Astrophysics
Klaus Dolag – Max-Planck-Institut für Astrophysik
Stefano Borgani & Co. - Universita' di Trieste
Massimo Ramella – INAF, Oss. Astron. di Trieste
Giuseppe Murante – INAF, Oss. Astron. di Torino
Local group:
Daniele Bertacca, Stefano Camera, Martina Giovalli, Luisa Ostorero, Ana Laura Serra
![Page 2: COSMOLOGY AND COSMIC STRUCTURES Antonaldo Diaferio Dipartimento di Fisica Generale Università degli Studi di Torino Torino, 8 aprile 2008 Current collaborators:](https://reader036.vdocuments.us/reader036/viewer/2022062421/56649d0c5503460f949e0f35/html5/thumbnails/2.jpg)
- Energy content of the Universe
- Clusters of galaxies
- Distribution of galaxies on large scales:
galaxy formation
- Alternative theories of gravity
Outline
![Page 3: COSMOLOGY AND COSMIC STRUCTURES Antonaldo Diaferio Dipartimento di Fisica Generale Università degli Studi di Torino Torino, 8 aprile 2008 Current collaborators:](https://reader036.vdocuments.us/reader036/viewer/2022062421/56649d0c5503460f949e0f35/html5/thumbnails/3.jpg)
THE MATTER/ENERGY CONTENT OF THE UNIVERSE
?
?
![Page 4: COSMOLOGY AND COSMIC STRUCTURES Antonaldo Diaferio Dipartimento di Fisica Generale Università degli Studi di Torino Torino, 8 aprile 2008 Current collaborators:](https://reader036.vdocuments.us/reader036/viewer/2022062421/56649d0c5503460f949e0f35/html5/thumbnails/4.jpg)
WHERE DO WE GET THIS RESULT FROM?
ΩΛ
Ωm
vacuum energy density
geometry
mass density
![Page 5: COSMOLOGY AND COSMIC STRUCTURES Antonaldo Diaferio Dipartimento di Fisica Generale Università degli Studi di Torino Torino, 8 aprile 2008 Current collaborators:](https://reader036.vdocuments.us/reader036/viewer/2022062421/56649d0c5503460f949e0f35/html5/thumbnails/5.jpg)
Early astrophysical evidence of DM
By using Newton/Einstein+ virial theorem:
Coma cluster
GM = 3σ2R ≃100Σmgal
Zwicky 1933
Total cluster mass sum of masses of individual galaxies
![Page 6: COSMOLOGY AND COSMIC STRUCTURES Antonaldo Diaferio Dipartimento di Fisica Generale Università degli Studi di Torino Torino, 8 aprile 2008 Current collaborators:](https://reader036.vdocuments.us/reader036/viewer/2022062421/56649d0c5503460f949e0f35/html5/thumbnails/6.jpg)
The 1980's: X-ray emission
NGC2300 group
m ~ 0.25
Hydra cluster
GM(<r) ~ kBT
Xr (hydro-static eq.)
gas temperature
![Page 7: COSMOLOGY AND COSMIC STRUCTURES Antonaldo Diaferio Dipartimento di Fisica Generale Università degli Studi di Torino Torino, 8 aprile 2008 Current collaborators:](https://reader036.vdocuments.us/reader036/viewer/2022062421/56649d0c5503460f949e0f35/html5/thumbnails/7.jpg)
Strong lensing
Weak lensing
GM(<r) ~ αrc2
m ~ 0.25
deflection angle
Dropping the dynamical equilibrium hypothesis. The 1990's: Gravitational lensing
![Page 8: COSMOLOGY AND COSMIC STRUCTURES Antonaldo Diaferio Dipartimento di Fisica Generale Università degli Studi di Torino Torino, 8 aprile 2008 Current collaborators:](https://reader036.vdocuments.us/reader036/viewer/2022062421/56649d0c5503460f949e0f35/html5/thumbnails/8.jpg)
Dropping the dynamical equilibrium hypothesis: The caustic technique
CL0024 Sky Redshift diagram
CausticsCaustic
amplitude=
escape velocityDiaferio & Geller 1997m ~ 0.25
![Page 9: COSMOLOGY AND COSMIC STRUCTURES Antonaldo Diaferio Dipartimento di Fisica Generale Università degli Studi di Torino Torino, 8 aprile 2008 Current collaborators:](https://reader036.vdocuments.us/reader036/viewer/2022062421/56649d0c5503460f949e0f35/html5/thumbnails/9.jpg)
Diaferio et al. 2005
CLUSTER MASSES: Comparing X-ray, Lensing and Caustics
in three clusters
3D mass profile
projectedmass profile
caustics
lensing
X-ray
![Page 10: COSMOLOGY AND COSMIC STRUCTURES Antonaldo Diaferio Dipartimento di Fisica Generale Università degli Studi di Torino Torino, 8 aprile 2008 Current collaborators:](https://reader036.vdocuments.us/reader036/viewer/2022062421/56649d0c5503460f949e0f35/html5/thumbnails/10.jpg)
THE CENTER FOR ASTROPHYSICS REDSHIFT SURVEY (1978-1999)
20.000 galaxies
Sky projection
redshift survey
redshift 15000 km/s
Milky Way
de Lapparent, Geller & Huchra 1986;Falco et al. 1999
Catalogue of galaxieswith measured positionsand distance (redshift)
![Page 11: COSMOLOGY AND COSMIC STRUCTURES Antonaldo Diaferio Dipartimento di Fisica Generale Università degli Studi di Torino Torino, 8 aprile 2008 Current collaborators:](https://reader036.vdocuments.us/reader036/viewer/2022062421/56649d0c5503460f949e0f35/html5/thumbnails/11.jpg)
The 2dF REDSHIFT SURVEY
The CfA RS
Colless et al 2001
![Page 12: COSMOLOGY AND COSMIC STRUCTURES Antonaldo Diaferio Dipartimento di Fisica Generale Università degli Studi di Torino Torino, 8 aprile 2008 Current collaborators:](https://reader036.vdocuments.us/reader036/viewer/2022062421/56649d0c5503460f949e0f35/html5/thumbnails/12.jpg)
THE FORMATION OF COSMIC STRUCTURES:
CDM
by Ben Moore
![Page 13: COSMOLOGY AND COSMIC STRUCTURES Antonaldo Diaferio Dipartimento di Fisica Generale Università degli Studi di Torino Torino, 8 aprile 2008 Current collaborators:](https://reader036.vdocuments.us/reader036/viewer/2022062421/56649d0c5503460f949e0f35/html5/thumbnails/13.jpg)
THE FORMATION OF COSMIC STRUCTURES
IN CDM MODELS:
Diaferio et al. 1999 (GIF sims.)
DM+Galaxies (semi-analytic modeling)
z=3
z=1
z=2
z=0
![Page 14: COSMOLOGY AND COSMIC STRUCTURES Antonaldo Diaferio Dipartimento di Fisica Generale Università degli Studi di Torino Torino, 8 aprile 2008 Current collaborators:](https://reader036.vdocuments.us/reader036/viewer/2022062421/56649d0c5503460f949e0f35/html5/thumbnails/14.jpg)
From a new redshift survey: SHELS (Geller et al.)
![Page 15: COSMOLOGY AND COSMIC STRUCTURES Antonaldo Diaferio Dipartimento di Fisica Generale Università degli Studi di Torino Torino, 8 aprile 2008 Current collaborators:](https://reader036.vdocuments.us/reader036/viewer/2022062421/56649d0c5503460f949e0f35/html5/thumbnails/15.jpg)
SIMULATIONS WITH ORDINARY (BARYONIC) MATTER: Diffuse IGM
and GalaxiesN-body/hydro-simulations
gas density gas temperature
Borgani et al. 2004
![Page 16: COSMOLOGY AND COSMIC STRUCTURES Antonaldo Diaferio Dipartimento di Fisica Generale Università degli Studi di Torino Torino, 8 aprile 2008 Current collaborators:](https://reader036.vdocuments.us/reader036/viewer/2022062421/56649d0c5503460f949e0f35/html5/thumbnails/16.jpg)
COSMIC STRUCTURES
Forming a cluster
gas density stars
by Klaus Dolag
![Page 17: COSMOLOGY AND COSMIC STRUCTURES Antonaldo Diaferio Dipartimento di Fisica Generale Università degli Studi di Torino Torino, 8 aprile 2008 Current collaborators:](https://reader036.vdocuments.us/reader036/viewer/2022062421/56649d0c5503460f949e0f35/html5/thumbnails/17.jpg)
List of the non-gravitational processes
adiabatic compression
shock heating
radiative heating and cooling
thermal conduction
reionization
star formation and evolution
feedback from supernovae explosion
galactic winds
chemical enrichment
feedback from active galactic nuclei
non-thermal processes (magnetic fields, cosmic ray production)
sub-resolutionprocesses
![Page 18: COSMOLOGY AND COSMIC STRUCTURES Antonaldo Diaferio Dipartimento di Fisica Generale Università degli Studi di Torino Torino, 8 aprile 2008 Current collaborators:](https://reader036.vdocuments.us/reader036/viewer/2022062421/56649d0c5503460f949e0f35/html5/thumbnails/18.jpg)
THE MATTER/ENERGY CONTENT OF THE UNIVERSE
?
?
![Page 19: COSMOLOGY AND COSMIC STRUCTURES Antonaldo Diaferio Dipartimento di Fisica Generale Università degli Studi di Torino Torino, 8 aprile 2008 Current collaborators:](https://reader036.vdocuments.us/reader036/viewer/2022062421/56649d0c5503460f949e0f35/html5/thumbnails/19.jpg)
The standard solution to DM
Supersymmetry (beyond the SM) suggests a number of candidates:
neutralinos, sneutrinos, gravitinos, axinos, ...
but other candidates are axions, sterile neutrinos, “wimpzillas”, ...
However:
neither direct search (accelerators, energy recoil from nucleus hit)
nor indirect search (gamma-ray, neutrino and anti-matter astronomy)
has yet proved the existence of these particles.
![Page 20: COSMOLOGY AND COSMIC STRUCTURES Antonaldo Diaferio Dipartimento di Fisica Generale Università degli Studi di Torino Torino, 8 aprile 2008 Current collaborators:](https://reader036.vdocuments.us/reader036/viewer/2022062421/56649d0c5503460f949e0f35/html5/thumbnails/20.jpg)
The standard solution to DE (I)
Rμν
- ½ gμν
R = 8πG/c4 Tμν
+ Λ gμν
/c2
ρΛ = -p
Λ/c2 = Λc2/8πG
ρΛ → ρ
v
pΛ → p
v = -ρ
vc2
The DE fluid:
The vacuumenergy density interpretation
ρv~ 10-48 GeV4
![Page 21: COSMOLOGY AND COSMIC STRUCTURES Antonaldo Diaferio Dipartimento di Fisica Generale Università degli Studi di Torino Torino, 8 aprile 2008 Current collaborators:](https://reader036.vdocuments.us/reader036/viewer/2022062421/56649d0c5503460f949e0f35/html5/thumbnails/21.jpg)
Einstein-Hilbert action:
SEH
=(16GN)-1 ∫ L (-g)1/2 d4x= (16G
N)-1 ∫ (-g)1/2 R d4x
Can avoid DM & DE:
metric theories L= f(R) where f is arbitrary (e.g. power laws, logarithms, etc.)
additional fields scalar-tensor theories (introduced by Jordan 1955, Brans-Dicke 1961) TeVeS (Bekenstein 2004) STVG (Moffat 2006)
(they have G and other constants varying with time)modification of the nature of the space-time geometry torsion (
not symmetric in : might be relevant for microphysics) non-symmetric metric g (e.g. Moffat: NGT nonsymmetric gravity theory1995,
MSTG=metric skew tensor gravity 2005) generalized Riemann geometry (Weyl, who introduced the conformal
transformations) additional symmetries Conformal gravity (Mennheim 2006)
Can avoid DE only:
from additional space-time dimension of M-theory: brane cosmologies
Zoology of alternative gravities
![Page 22: COSMOLOGY AND COSMIC STRUCTURES Antonaldo Diaferio Dipartimento di Fisica Generale Università degli Studi di Torino Torino, 8 aprile 2008 Current collaborators:](https://reader036.vdocuments.us/reader036/viewer/2022062421/56649d0c5503460f949e0f35/html5/thumbnails/22.jpg)
Ltot = (-g)1/2[R + L(X,)] + Lmatter
X = (-1/2)DD
w=p/(2Xp'-p); p=L
UNIFIED DARK MATTER MODELS
@ high density: DM@ low density: DE
e.g. generalized Chaplygin gasp=-
V(r) = (½) exp(-2) (1+l2/r2) - (½) E2 exp[-)]
ds2=-exp(2)dt2+exp(2)dr2+r2d
Effective spherical potential
![Page 23: COSMOLOGY AND COSMIC STRUCTURES Antonaldo Diaferio Dipartimento di Fisica Generale Università degli Studi di Torino Torino, 8 aprile 2008 Current collaborators:](https://reader036.vdocuments.us/reader036/viewer/2022062421/56649d0c5503460f949e0f35/html5/thumbnails/23.jpg)
The Mannheim-Kazanas (MK) parameterization:
(Walker 1994, Edery & Paranjape 1998, Pireaux 2004a,b)
> 0 0
gravitational potentialdeflection angle
metric
geodesicequation
CONFORMAL GRAVITY BASICS
massive particles: E>0photons: E=0
independent of 2
action
![Page 24: COSMOLOGY AND COSMIC STRUCTURES Antonaldo Diaferio Dipartimento di Fisica Generale Università degli Studi di Torino Torino, 8 aprile 2008 Current collaborators:](https://reader036.vdocuments.us/reader036/viewer/2022062421/56649d0c5503460f949e0f35/html5/thumbnails/24.jpg)
SIMULATION RESULTS
Temperature evolution
2 Mpc
X-ray surf. bright. evolution
![Page 25: COSMOLOGY AND COSMIC STRUCTURES Antonaldo Diaferio Dipartimento di Fisica Generale Università degli Studi di Torino Torino, 8 aprile 2008 Current collaborators:](https://reader036.vdocuments.us/reader036/viewer/2022062421/56649d0c5503460f949e0f35/html5/thumbnails/25.jpg)
Conclusions
By assuming GR, the astrophysical observations imply an overwhelming amount of DM + DE
compared to ordinary matter.
This conclusion rests on the understanding of the astrophysical sources,
and the control of systematics.