The “Big Question” of Cosmology
Cosmology and Religion in Art
1 The Dark Night Sky
The Hubble Ultradeep Field
2 Darkness at Night: Olbers’ Paradox
The Large Forest Analogy
3 Edgar Allen Poe
4 The Cosmic Distance Ladder
The Cosmic Distance Ladder
1 Distance Measurements via Parallax
Hipparcos Satellite Before Launch
2 GAIA – A Planned Future Mission
Estimating the Distance to a Stop Light
3 Cepheid Variable Stars
The Period-Luminosity Relation for Cepheid Variable Stars
Henrietta Leavitt
4 HST Observations of Cepheid Variable Stars in M100 at ~ 20 Mpc
HST key project measured Cepheid distances to ~ 25 galaxies within 25 Mpc.
An Example Globular Cluster
5 Distances from Type 1a Supernovae
Origin of Type 1a Supernovae
6 Mass Discovery of Type 1a Supernovae
Light Curves of Type 1a Supernovae
Peak luminosity and subsequent fading are related.
7 SNAP – A Planned Mission to Measure Distances to Type 1a Supernovae
Radioactive Decay
8 Oldest Rocks on Earth
Oldest Rocks on Earth
9 Oldest Rocks from the Moon
4.6 Billion Year Old Meteorite
10 The Oldest Star Clusters
The Oldest White Dwarfs
11 The Andromeda Galaxy
Some of the Most Distant Galaxies
12 Optical Spectrum of a Galaxy
Recession velocity = 14387 km / s Hα z = 0.0479 Flux
Hβ
[O III]
Vesto Slipher
1 Redshifted Spectra
Redshifted Spectra
2 Edwin Hubble
The Original Hubble Law
3 Modern-Day Hubble Law
Today our best value for the Hubble constant is 70 +/- 5 km / s / Mpc.
Measurements of the Hubble Constant
4 Recent Measurements of the Hubble Constant
Raisin-Bread Analogy
5 Balloon Analogy
Einstein’s General Theory of Relativity - 1915
6 Willem De Sitter
Einstein with Hubble
7 TheThe LocalLocal GroupGroup
Members of the IC 342 / Maffei Group
IC 342
1 The IC 342 / Maffei Group
Hickson Compact Groups
2 Hot X-ray Emitting Gas in a Group of Galaxies
NGC 2300 Group of Galaxies
The Virgo Cluster of Galaxies
3 M87: The Giant Galaxy in the Core of the Virgo Cluster
The Coma Cluster of Galaxies
4 The Hercules Cluster of Galaxies
Abell 3528 – A Cluster Merger
5 300 of the Brightest X-ray Clusters in the Sky
Gravitational Lensing in Abell 2218
6 Nearby Clusters of Galaxies
Nearby Superclusters
7 Sloan Digital Sky Survey: Example of Galaxy Survey Methods
Distribution of Galaxies in the Universe from the 2dF Survey
8 Distribution of Galaxies in the Universe from the Sloan Digital Sky Survey
Comparison of Redshift Surveys
9 Redshift Clustering in the Hubble Deep Field-North
Superclustering Seen in X-rays
About 6 Mpc across
10 Simulations of Galaxy and Structure Formation
Largest Simulation to Date
11 “Power Spectrum” of Density Variations on Different Scales
“Power Spectrum” of Density Variations on Different Scales
12 Uniformity on the Very Largest Scales - Radio Galaxies
Sky Distribution of Radio Sources from the NRAO VLA Sky Survey
Uniformity on the Very Largest Scales - Quasars
13 Uniformity on the Very Largest Scales - The Cosmic Microwave Background
14 Sun - Eight Minutes Ago
Nearest Stars - Few Years Ago
1 Andromeda Galaxy - 2.5 Million Years Ago
Distant Galaxies - Billions of Years Ago
2 Redshifts in the Hubble Deep Field-North
Effect of Distance on Observations of Galaxies and the Need for High Angular Resolution
3 Comparison of Ground-Based versus Space-Based Imaging
James Webb Space Telescope (JWST)
4 Simulated JWST Deep Field
Studying Distant Galaxies with Gravitational Lensing
5 Some of the Most Distant Known Galaxies: “Pieces” of Present-Day Galaxies
Galaxies at Intermediate Distances: Merging of the “Pieces”
6 Simulations of Forming Galaxies
The Earth Simulator Supercomputer
The Cosmic History of Star Formation in Galaxies
7 Merger-Induced Star Formation in the “Antennae”
Other Merging Systems - The “Mice” and the “Tadpole”
8 Star Formation Triggered by a Close Interaction and a Galactic Wind
“Super Star Clusters” in M82
9 “Super Star Clusters” in M101
Dust-Obscured Star Formation
Markarian 231
10 Submillimeter Galaxies: Dust-Obscured Star Formation in the Distant Universe
Evolution of the Quasar Population
11 Supermassive Black Holes in Nearby Galaxies: Relics of the Quasars
Relations Between Galaxy Bulges and Their Central Black Holes
Milky Way
Sombrero Galaxy
12 Active Galaxy Winds as an Agent of Black Hole vs. Galaxy Feedback
13 Modern-Day Hubble Law
Main Evidence for the Big Bang
The Hubble Law
The existence and properties of the cosmic microwave background
Primordial nucleosynthesis and the observed light element abundances
1 How Far Can We Look Back in Time?
The Plasma-to-Gas Transition of Our Universe - “Recombination” Plasma - Nuclei and Electrons Gas - Atoms
2 BlackbodyBlackbody RadiationRadiation
“Cooling” of the Cosmic Microwave Background
3 MicrowavesMicrowaves
Arno Penzias and Robert Wilson
4 Robert Dicke and Jim Peebles
George Gamow, Ralph Alpher, Robert Hermann
5 You Can “See” the CMB
Cyanogen - Effects from the CMB Were Noticed Before Its Discovery
6 Directly Observing the Cooling of the CMB
Cosmic Background Explorer (COBE)
7 Spectrum of the Cosmic Microwave Background
Uniformity of the CMB
8 Anisotropy of the Cosmic Microwave Background
Seeing the “Seeds” of Galaxies
9 Limitations of the COBE Maps
Examples of Balloon and Ground- Based CMB Experiments
Boomerang Cosmic Background Imager
10 Wilkinson Microwave Anisotropy Probe
Current All-Sky Maps of the Cosmic Microwave Background WMAP
11 The Power Spectrum of the CMB
Current Measurements of the CMB Power Spectrum
12 Cosmological Parameters from the CMB Power Spectrum
Polarization of the CMB
13 Planck: An Upcoming CMB Mission
14 Thermal History of the Universe
TooToo MuchMuch HeliumHelium
Our Sun is about 28% helium by mass.
1 George Gamow and Ralph Alpher
Nuclear Reactions in the Early Universe
2 Some More Details of the Nuclear Reactions in the Early Universe
One Reason Why Physicists Are Good at Calculating Nuclear Reactions
3 Primordial Nucleosynthesis
Measuring Cosmic Deuterium
4 The Life of Our Universe Before One Second
At Very Early Times Our Universe Was Filled With a Plasma of Quarks, Anti-Quarks, and Gluons
5 Attempts to Make Quark-Gluon Plasmas on Long Island
The Very Early Universe Contained Both Matter and Antimatter, in Nearly Equal Amounts
Carl Anderson
6 Baryogenesis: Somehow the Matter Slightly “Won” Over the Antimatter
Andrei Sakharov’s Conditions for Baryogenesis
7 Components of the Milky Way
Examples of Rotation Curves
1 Expected Versus Observed Rotation Curves for Our Galaxy
21 cm Radiation as Tracer of Gas Clouds
21 cm map of our Galaxy
2 The Correct Way to Think about Our Galaxy
Possible Dark-Matter Candidates
3 Evidence Against Red Dwarfs as the Dark Matter
Gravitational Microlensing
4 Microlensing Targets
Large Magellanic Cloud Small Magellanic Cloud
Microlensing Light Curves
5 Microlensing Light Curves
Microlensing by a Binary System
6 Neutrinos as Nonbaryonic Dark Matter
About 100 neutrinos per cubic cm, throughout space.
Mass is about 0.05 eV = 1 / 10,000,000 mass of Superkamiokande, an Example electron, although some uncertainty. of a Neutrino Observatory Neutrinos in the Universe have nearly as much mass as all of the stars!
Other Types of Nonbaryonic Dark Matter
XENON Dark Matter Detector
7 Large Hadron Collider at CERN
The LHC will search for supersymmetric and other new subatomic particles.
Dark Matter in M31 – Flat Rotation Curve
8 Dark Matter in Other Spiral Galaxies – Flat Rotation Curves
NGC 3198
Dark Matter in Elliptical Galaxies – Evidence from X-ray Gas
NGC 4697 optical NGC 4697 Chandra
9 Dark Matter in Clusters of Galaxies
The Coma Cluster Fritz Zwicky
Galaxy Motions in a Cluster of Galaxies
The Coma Cluster
10 X-ray Evidence for Dark Matter in Clusters of Galaxies
Need enough gravity to keep the X-ray gas from “boiling off” into intergalactic space.
Gravitational Lensing Evidence for Dark Matter in Clusters of Galaxies
11 Gravitational Lensing in Abell 2218
Gravitational Lensing in 0024+1654
12 Gravitational Lensing in Abell 1689
Gravitational Lensing in Abell 1689
13 Masses of Some Galaxy Clusters
The Acceleration of the Universe
Examples of type 1a supernovae
Thermonuclear detonation of white dwarf
High-redshift supernovae are systematically fainter than expected based on extrapolation of low-redshift sources.
Must be further away than expected. So need an effect to overcome the tendency of gravity to slow down the expansion.
14 Dark Energy in the Universe
Cosmic acceleration suggests presence of “dark energy” that drives space apart.
This “dark energy” dominates the mass-energy density of the Universe!
Supporting evidence comes from studies of the cosmic microwave background, clusters of galaxies, and large-scale structure.
What is this “dark energy”?
Why is there the observed amount, not much more or much less?
Schematic of Cosmic History
15 Dark-Energy Candidates
The Future of the Universe
We cannot predict the fate of the Universe until we understand dark energy.
16 Schematic of Cosmic History
From “Seeds” to Galaxies
1 Dark Matter Halos in the Early Universe
Star Formation in the Orion Nebula
2 Supercomputer Simulations of the Formation of the First Stars
The Sun Compared to the First Stars
3 Recipe for Forming the First Stars
The Deaths of the First Stars in Supernova Explosions
4 Future Prospects for Detecting the First Supernovae
James Webb Space Telescope Thirty Meter Telescope
Gamma-Ray Bursts from the First Stars?
5 A Gamma-Ray Burst at a Redshift of 6.29
Redshift Versus Time for Galaxies, Quasars, and Gamma-Ray Bursts
6 Environments of the First Quasars
Optical Spectra and X-ray Images of Some of the First Quasars
7 Uncertainty About the Very Early Universe
The Thermal History of the Universe
1 Uniformity of the Cosmic Microwave Background
The Horizon Problem
2 The Magnetic Monopole Problem
Alan Guth and the “Inflationary” Extension to the Hot Big Bang
3 Our Observable Horizon in an Inflationary Universe
The Fog Analogy for Our Observable Horizon
4 What is Beyond the Observable Universe?
Inflation and the Seeds of Cosmic Structure
5 Inflation and Dark Energy
Do We Live in a Multiverse?
6 Do Black Holes Represent the Formation of New Universes?
The Ultimate Realization of the Copernican Principle?
7 Other Universes Could Be Very Different From Ours
Biophilic Versus Biohazardous Universes
8 The Fine-Tuning Problem
Hitting the Bull’s Eye with a Biophilic Universe?
9 Hitting the Bull’s Eye with Earth?
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