progress on cosmology sarah bridle university college london
TRANSCRIPT
![Page 1: Progress on Cosmology Sarah Bridle University College London](https://reader035.vdocuments.mx/reader035/viewer/2022062715/56649da85503460f94a959c8/html5/thumbnails/1.jpg)
Progress on Cosmology
Sarah BridleUniversity College London
![Page 2: Progress on Cosmology Sarah Bridle University College London](https://reader035.vdocuments.mx/reader035/viewer/2022062715/56649da85503460f94a959c8/html5/thumbnails/2.jpg)
Progress on Cosmology
1. Definition of “Cosmology” for this talk2. The latest observations
2.1 Type Ia supernovae2.2 Galaxy clustering2.3 Cosmic shear
3. The future
![Page 3: Progress on Cosmology Sarah Bridle University College London](https://reader035.vdocuments.mx/reader035/viewer/2022062715/56649da85503460f94a959c8/html5/thumbnails/3.jpg)
Progress on Cosmology
1. Definition of “Cosmology” for this talk2. The latest observations
2.1Type Ia supernovae2.2 Galaxy clustering2.3 Cosmic shear
3. The future
![Page 4: Progress on Cosmology Sarah Bridle University College London](https://reader035.vdocuments.mx/reader035/viewer/2022062715/56649da85503460f94a959c8/html5/thumbnails/4.jpg)
My Definition of Observational Cosmology
Telescope observations of the Universe aimed at measuring global parameters
• Cosmic Microwave Background (CMB)– See talk by Francois Bouchet next
• Large-scale structure of the Universe, especially– Galaxy clustering– Clusters of galaxies– Gravitational lensing
• Standard candles e.g. Type Ia supernovae
![Page 5: Progress on Cosmology Sarah Bridle University College London](https://reader035.vdocuments.mx/reader035/viewer/2022062715/56649da85503460f94a959c8/html5/thumbnails/5.jpg)
Concordance Model
74% Dark Energy
22% Cold Dark Matter
4% Baryonic Matter
![Page 6: Progress on Cosmology Sarah Bridle University College London](https://reader035.vdocuments.mx/reader035/viewer/2022062715/56649da85503460f94a959c8/html5/thumbnails/6.jpg)
What Observational Cosmology Measures
• Post-inflation conditions– Scalar, tensor (+other?) perturbation power spectra
• The expansion rate (Hubble constant)• Baryonic matter density• Dark matter
– density, distribution – as f(time)
• Dark energy– density, distribution – as f(time)– Or modifications to GR (see de Rham talk on Friday)
![Page 7: Progress on Cosmology Sarah Bridle University College London](https://reader035.vdocuments.mx/reader035/viewer/2022062715/56649da85503460f94a959c8/html5/thumbnails/7.jpg)
Big Bang 5 billion years ago TodayCredit: Richard Massey, NASA
![Page 8: Progress on Cosmology Sarah Bridle University College London](https://reader035.vdocuments.mx/reader035/viewer/2022062715/56649da85503460f94a959c8/html5/thumbnails/8.jpg)
Why is the Universe Accelerating?
• Einstein’s cosmological constant
• A new fluid called Dark Energy– Equation of state w=p/
• General Relativity is wrong
![Page 9: Progress on Cosmology Sarah Bridle University College London](https://reader035.vdocuments.mx/reader035/viewer/2022062715/56649da85503460f94a959c8/html5/thumbnails/9.jpg)
Progress on Cosmology
1. Definition of “Cosmology” for this talk2. The latest observations
2.1 Type Ia supernovae2.2 Galaxy clustering2.3 Cosmic shear
3. The future
![Page 10: Progress on Cosmology Sarah Bridle University College London](https://reader035.vdocuments.mx/reader035/viewer/2022062715/56649da85503460f94a959c8/html5/thumbnails/10.jpg)
![Page 11: Progress on Cosmology Sarah Bridle University College London](https://reader035.vdocuments.mx/reader035/viewer/2022062715/56649da85503460f94a959c8/html5/thumbnails/11.jpg)
Latest Supernova Compilation
Hicken et al 2009
Matter DensityDar
k En
ergy
Equ
ation
of S
tate
w
Redshift
Dis
tanc
eD
ista
nce
– di
stan
ce if
no
DE
![Page 12: Progress on Cosmology Sarah Bridle University College London](https://reader035.vdocuments.mx/reader035/viewer/2022062715/56649da85503460f94a959c8/html5/thumbnails/12.jpg)
Progress on Cosmology
1. Definition of “Cosmology” for this talk2. The latest observations
2.1 Type Ia supernovae2.2 Galaxy clustering2.3 Cosmic shear
3. The future
![Page 13: Progress on Cosmology Sarah Bridle University College London](https://reader035.vdocuments.mx/reader035/viewer/2022062715/56649da85503460f94a959c8/html5/thumbnails/13.jpg)
Galaxy Clustering Constraints on Dark Energy
Hicken et al 2009, showing results using Eisenstein et al 2005
Dar
k En
ergy
Equ
ation
of S
tate
w
1-Matter Density
![Page 14: Progress on Cosmology Sarah Bridle University College London](https://reader035.vdocuments.mx/reader035/viewer/2022062715/56649da85503460f94a959c8/html5/thumbnails/14.jpg)
Neutrino Mass Constraints from Galaxy Clustering
Thomas, Abdalla & Lahav 2010
Matter Density
m
![Page 15: Progress on Cosmology Sarah Bridle University College London](https://reader035.vdocuments.mx/reader035/viewer/2022062715/56649da85503460f94a959c8/html5/thumbnails/15.jpg)
Progress on Cosmology
1. Definition of “Cosmology” for this talk2. The latest observations
2.1 Type Ia supernovae2.2 Galaxy clustering2.3 Cosmic lensing
3. The future
![Page 16: Progress on Cosmology Sarah Bridle University College London](https://reader035.vdocuments.mx/reader035/viewer/2022062715/56649da85503460f94a959c8/html5/thumbnails/16.jpg)
Gravitational Lensing
![Page 17: Progress on Cosmology Sarah Bridle University College London](https://reader035.vdocuments.mx/reader035/viewer/2022062715/56649da85503460f94a959c8/html5/thumbnails/17.jpg)
![Page 18: Progress on Cosmology Sarah Bridle University College London](https://reader035.vdocuments.mx/reader035/viewer/2022062715/56649da85503460f94a959c8/html5/thumbnails/18.jpg)
Tyson et al 2000
Cosmic Lensing
![Page 19: Progress on Cosmology Sarah Bridle University College London](https://reader035.vdocuments.mx/reader035/viewer/2022062715/56649da85503460f94a959c8/html5/thumbnails/19.jpg)
Universe was 0.2 Gyr old
Credit: Springel et al. (2005)
![Page 20: Progress on Cosmology Sarah Bridle University College London](https://reader035.vdocuments.mx/reader035/viewer/2022062715/56649da85503460f94a959c8/html5/thumbnails/20.jpg)
Universe was 1 Gyr old
Credit: Springel et al. (2005)
![Page 21: Progress on Cosmology Sarah Bridle University College London](https://reader035.vdocuments.mx/reader035/viewer/2022062715/56649da85503460f94a959c8/html5/thumbnails/21.jpg)
Universe was 4.7 Gyrs old
Credit: Springel et al. (2005)
![Page 22: Progress on Cosmology Sarah Bridle University College London](https://reader035.vdocuments.mx/reader035/viewer/2022062715/56649da85503460f94a959c8/html5/thumbnails/22.jpg)
Today (13.6 Gyr)
Credit: Springel et al. (2005)
![Page 23: Progress on Cosmology Sarah Bridle University College London](https://reader035.vdocuments.mx/reader035/viewer/2022062715/56649da85503460f94a959c8/html5/thumbnails/23.jpg)
Results from the HST COSMOS Survey
![Page 24: Progress on Cosmology Sarah Bridle University College London](https://reader035.vdocuments.mx/reader035/viewer/2022062715/56649da85503460f94a959c8/html5/thumbnails/24.jpg)
![Page 25: Progress on Cosmology Sarah Bridle University College London](https://reader035.vdocuments.mx/reader035/viewer/2022062715/56649da85503460f94a959c8/html5/thumbnails/25.jpg)
Progress on Cosmology
1. Definition of “Cosmology” for this talk2. The latest observations
2.1 Type Ia supernovae2.2 Galaxy clustering2.3 Cosmic shear
3. The future
![Page 26: Progress on Cosmology Sarah Bridle University College London](https://reader035.vdocuments.mx/reader035/viewer/2022062715/56649da85503460f94a959c8/html5/thumbnails/26.jpg)
The Future
JDEM
See Moniez talk on Friday
![Page 27: Progress on Cosmology Sarah Bridle University College London](https://reader035.vdocuments.mx/reader035/viewer/2022062715/56649da85503460f94a959c8/html5/thumbnails/27.jpg)
Gravitational shear has the greatest potentialBig uncertainty largely due to shear measurement techniques
Maybe dark energy is the wrong model...
Galaxy clustering
Supernovae Gravitationalshear
Comparison of different methods
![Page 28: Progress on Cosmology Sarah Bridle University College London](https://reader035.vdocuments.mx/reader035/viewer/2022062715/56649da85503460f94a959c8/html5/thumbnails/28.jpg)
Future prospects
• Cosmic microwave background radiation– Distribution of dark matter at early times
• Distribution of galaxies – Some clues to distribution of matter
• Galaxy velocities– Galaxies fall towards dark matter clumps
• Gravitational lensing
The Dark Energy Survey
![Page 29: Progress on Cosmology Sarah Bridle University College London](https://reader035.vdocuments.mx/reader035/viewer/2022062715/56649da85503460f94a959c8/html5/thumbnails/29.jpg)
C3
C1
![Page 30: Progress on Cosmology Sarah Bridle University College London](https://reader035.vdocuments.mx/reader035/viewer/2022062715/56649da85503460f94a959c8/html5/thumbnails/30.jpg)
20 000 sq deg RIZAB ≤ 24.5 at 0.16” FWHM, yielding 30-40 resolved galaxies/amin2, z~ 0.9NIR photometry: Y, J, H ≤ 24 (AB, 5σ PS). Spectroscopy.
Refregier et al Science Book arxiv:1001.0061
Galactic Plane
Deep~40 deg2
Wide Extragalactic20,000 deg2
![Page 31: Progress on Cosmology Sarah Bridle University College London](https://reader035.vdocuments.mx/reader035/viewer/2022062715/56649da85503460f94a959c8/html5/thumbnails/31.jpg)
HST COSMOS
![Page 32: Progress on Cosmology Sarah Bridle University College London](https://reader035.vdocuments.mx/reader035/viewer/2022062715/56649da85503460f94a959c8/html5/thumbnails/32.jpg)
End
![Page 34: Progress on Cosmology Sarah Bridle University College London](https://reader035.vdocuments.mx/reader035/viewer/2022062715/56649da85503460f94a959c8/html5/thumbnails/34.jpg)
![Page 35: Progress on Cosmology Sarah Bridle University College London](https://reader035.vdocuments.mx/reader035/viewer/2022062715/56649da85503460f94a959c8/html5/thumbnails/35.jpg)
The camera: DECam
Hexapod
Corrector Lenses
CCDReadout
Filters Shutter
Mechanical Interface of DECam Project to the Blanco
Focal plane (detector)
![Page 36: Progress on Cosmology Sarah Bridle University College London](https://reader035.vdocuments.mx/reader035/viewer/2022062715/56649da85503460f94a959c8/html5/thumbnails/36.jpg)
Kowalski et al 2008
![Page 37: Progress on Cosmology Sarah Bridle University College London](https://reader035.vdocuments.mx/reader035/viewer/2022062715/56649da85503460f94a959c8/html5/thumbnails/37.jpg)
Ground vs Space
weak lensing shear
space
ground
![Page 38: Progress on Cosmology Sarah Bridle University College London](https://reader035.vdocuments.mx/reader035/viewer/2022062715/56649da85503460f94a959c8/html5/thumbnails/38.jpg)
Larson et al 2010, WMAP7