File: etc/phys016 - item number: 0
Physics 016: The Course Notes, spring 2005.
An important remark: the course notes are divided into sections and subsections, with titles as shown below. Please note that the division is meant to be logical, by topic. You should not necessarily assume that that one section of notes corresponds to exactly one lecture! The important thing is to read them sequentially, and to refer to the
suggested readings in the textbook and elsewhere which are intended to parallel these discussions.
Contents:
1. The Properties of the Sun
1.1: A Point-Form Summary
1.2: Associated Readings from the Text
1.3: The Sun's Luminosity
1.4: The Mass of the Sun
1.5: The Size and Density of the Sun
1.6: The Rotation of the Sun
1.7: The Interior Structure of the Sun
2. What Is The Sun Doing?
2.1: A Point-Form Summary
2.2: Associated Readings from the Text
2.3: The Sun's Behaviour: Two Possibilities
2.4: The Paradoxical Behaviour of the Sun
2.5: The Ultimate Fate
2.6: Is the Sun Slowly Shrinking? Kelvin Contraction
2.7: An Important Point About The Original Heat
2.8: Another Possible Heat Source: Chemical Reactions
3. An Introduction to Thermonuclear Fusion
3.1: A Point-Form Summary
3.2: Associated Readings from the Text
3.3: Energy from Mass
3.4: The Importance of Temperature
3.5: A Semantic Point
3.6: The Composition of the Sun
3.7: How Structurally Stable is the Sun?
3.8: A Mathematical Exercise
3.9: The Sun in Cross-Section
3.10: The States of Matter
3.11: A Brief Reminder of Atomic Structure
3.12: The Binding Energy Curve
3.13: The Sun: Not Exactly a Bomb
3.14: A Digression: The Atomic Bomb vs the Hydrogen Bomb
3.15: Back to Fusion in the Sun: The Proton-Proton Chain
3.16: How Do We Know All This?
3.17: The Positron and Its Uses
4. Probing the Deep Interior of the Sun
4.1: A Point-Form Summary
4.2: Associated Readings from the Text
4.3: Delayed at the Airport
4.4: Other PP Branches
4.5: The CNO Cycle
4.6: The Importance of Temperature, Revisited
4.7: Probing the Solar Interior: The Drunkard's Walk
4.8: Old News
4.9: Neutrinos Predicted: A Victory for Classical Physics
4.10: Neutrino Observatories: The First Attempts
4.11: Limitations on the Experiment
4.12: The Results
4.13: The Sudbury Neutrino Observatory: How It Works
5. The Sun in More Detail
5.1: A Point-Form Summary
5.2: Associated Readings from the Text
5.3: The Face of the Sun
5.4: Sunspots: Their Appearance and Phenomenology
5.5: Sunspots: Their Nature
5.6: Sunspots: The Patterns
5.7: Similar Behaviour in the Earth
5.8: The Earth-Sun Connection: A Scientific Case-Study
5.9: The Sunspot Connection: Some (Real?) Effects
5.10: Sunspots on Other Stars
5.11: GONG: Lessons from Seismology and Music
6. An Introduction to the Stars
6.1: A Point-Form Summary
6.2: Associated Readings from the Text
6.3: A Change of Scale
6.4: The Isolation of the Stars
6.5: What Would You Like to Know?
6.6: Even More Questions
6.7: In the Absence of...
6.8: Positions and Motions
6.9: The Motion of the Sun
6.10: The Apparent Brightnesses of the Stars
6.11: Colours, Temperatures - and Dust!
7. Stars and Their Distances
7.1: A Point-Form Summary
7.2: Associated Readings from the Text
7.3: Stellar Variability
7.4: Extrinsic Variables: Binary Stars
7.5: Intrinsic Variables
7.6: A Few Lines on a Chart
7.7: First Thoughts
7.8: Picking the Wrong Targets
7.9: Units of Distance Measurement
7.10: A Serendipitous Discovery
7.11: Increasing the Sample
7.12: What Can We Derive?
8. The HR Diagram
8.1: A Point-Form Summary
8.2: Associated Readings from the Text
8.3: A Search for Correlations
8.4: A Second Correlation
8.5: A Breakthrough in Understanding
9. Questions Arising from the HR Diagram
9.1: A Point-Form Summary
9.2: Associated Readings from the Text
9.3: Selection Effects: The Demographics of Stellar Populations
9.4: The Sun as a Representative Star
9.5: Telling Giants from Main Sequence Stars
9.6: Determining the Distances of Remote Stars by Spectroscopic Parallax
9.7: Do the Stars Change As Time Passes?
10. The Importance of Binary Stars
10.1: A Point-Form Summary
10.2: Associated Readings from the Text
10.3: Binary Stars Are Not Rare
10.4: Optical Doubles: Not Binaries!
10.5: Visual Binaries
10.6: Spectroscopic Binaries
10.7: Single-Lined Spectroscopic Binaries
10.8: Eclipsing Binaries
10.9: Astrometric Binaries
10.10: Final Remarks: Stellar Masses
11. Implications from Stellar Masses
11.1: A Point-Form Summary
11.2: Associated Readings from the Text
11.3: Stellar Masses
11.4: An Important Semantic Point
11.5: Do Stars Evolve Along the Main Sequence as They Age?
11.6: Why Should the Mass Matter So Much?
11.7: The Mass-Luminosity Law
11.8: The Main-Sequence Lifetimes of the Stars
12. Late in the Life of the Sun
12.1: A Point-Form Summary
12.2: Associated Readings from the Text
12.3: The Importance of Mass
12.4: Why These Lifetimes?
12.5: Slow Changes in the Core of the Star
12.6: The Behaviour of a Hypothetical Helium Star
12.7: Back to the Sun Itself
12.8: Defending the Fortress
12.9: What Does Helium Turn Into? The Triple-Alpha Process
12.10: How Will the Sun Look Late in Its Life?
12.11: How Do We Know This? The Difficulty
12.12: How Do We Know This? The Answer
13. The Importance of Star Clusters in Understanding Stellar Evolution
13.1: A Point-Form Summary
13.2: Associated Readings from the Text
13.3: The Use and Importance of Star Clusters
13.4: Are Star Clusters Real?
13.5: The Pace of Stellar Evolution
13.6: Remarks on Protostars
13.7: Imagine a Cluster in Formation
13.8: The Deaths of the Cluster Stars
13.9: Estimating Stellar Ages
13.10: The Turnoff Age
13.11: Not Only Red Giants!
13.12: The Practical Realities
13.13: Some Real Clusters
13.14: A Real Research Example
13.15: The Crowded Confines of a Star Cluster
13.16: Is the Sun in a Cluster at Present?
13.17: Was the Sun Ever in a Cluster?
13.18: The Kinds of Clusters
14. The Chandrasekhar Limit
14.1: A Point-Form Summary
14.2: Associated Readings from the Text
14.3: Your Expectations
14.4: The Importance of Quantum Mechanical Effects
14.5: Electron Degeneracy: The Exclusion Principle
14.6: In the Core of the Sun
14.7: The Story of Chandrasekhar
14.8: Chandra's Earliest Work: The Chandrasekhar Limit
14.9: Chandra's Later Contributions
14.10: Twinkle, Twinkle
14.11: The Diamond Exposed
14.12: Planetary Nebulae
14.13: Why Does the Star Shed Its Skin?
14.14: A White Dwarf Forever
15. Supernovae: The Deaths of Massive Stars
15.1: A Point-Form Summary
15.2: Associated Readings from the Text
15.3: A Quick Review of the Low-Mass Stars
15.4: More Massive Stars: Onion-Skin Models
15.5: The Odd-Even Effect Explained
15.6: Iron Stars: The End of It All
15.7: What Now? Some Thoughts
15.8: Neutron Degeneracy: Neutron Stars Predicted
15.9: Forming Neutron Stars
15.10: Perfect Billiard Balls
15.11: Supernovae: The Fireworks That Go With Neutron Star Birth
15.12: Other Components of the Supernova
15.13: Forming Even Heavier Elements; Enriching the ISM
15.14: A Case Study of a Supernova: 1987A
15.15: The Detectability of Neutron Stars
16. Pulsars
16.1: A Point-Form Summary
16.2: Associated Readings from the Text
16.3: The Discovery of Pulsars
16.4: A Sad Corollary
16.5: Pulsars as Lighthouses
16.6: Cyclotrons
16.7: A Complication: The Synchrotron
16.8: Synchrotron Radiation
16.9: The Oblique Rotator
16.10: Pulsars: The Beacon Observed
16.11: Pulsar Slowdown
16.12: Pulsar Spin-Up
16.13: The Crab Nebula: An Ancient Supernova
16.14: The Crab Nebula: The Connection Proven
17. Novae
17.1: A Point-Form Summary
17.2: Associated Readings from the Text
17.3: Back to Binary Stars
17.4: Degrees of Connectedness
17.5: Mass Exchange and Its Inevitability
17.6: The Details: Slow Accumulation
17.7: The Effect of the Infall on Ordinary Stars
17.8: Back and Forth
17.9: Fuel Onto the Fire
17.10: Novae Observed
17.11: But Not the Sun
17.12: One More Kind of Supernova
18. An Introduction to Black Holes
18.1: A Point-Form Summary
18.2: Associated Readings from the Text
18.3: The Inevitability of Black Holes: An Introduction to Relativity
18.4: What Relativity Means: The Strange Behaviour of Light
18.5: Why Einsteinian Relativity `Works' the Way It Does
18.6: Time Dilatation
18.7: A Helpful Visualisation
19. Gravity as Geometry
19.1: A Point-Form Summary
19.2: Associated Readings from the Text
19.3: A Fresh Look at Gravity
19.4: Light Itself
19.5: The Bending of Starlight by the Sun
19.6: The Anomalous Precession of Mercury's Orbit
19.7: Look at All Those Fish! Gravitational Lensing
19.8: Gravitational Redshift
19.9: Making a Strong Gravitational Field
19.10: Black Holes Foreseen
19.11: Are Black Holes Really Inevitable?
19.12: Light Near a Black Hole
19.13: The Schwarzschild Radius
19.14: Not Really Vanished
20. Finishing Off Black Holes
20.1: A Point-Form Summary
20.2: Associated Readings from the Text
20.3: Exploring a Black Hole
20.4: Searching for Black Holes
20.5: Not a General Inflow
20.6: Gravitational Focussing: MACHO
20.7: Black Hole Binaries
20.8: Supermassive Black Holes
20.9: The Fate of Black Holes
21. Star Formation
21.1: A Point-Form Summary
21.2: Associated Readings from the Text
21.3: Stellar Nurseries
21.4: Signposts of Star Formation
21.5: The Orion Nebula
21.6: Putting It All Together: The Full Cycle
22. Dust in the Interstellar Medium
22.1: A Point-Form Summary
22.2: Associated Readings from the Text
22.3: The General Interstellar Medium (ISM)
22.4: How Might Interstellar Material Make Its Presence Known?
22.5: Dust: The Dimming of the Stars
22.6: Why is the Sky Blue?
22.7: Expectations for the ISM - and the Reality
22.8: The Interstellar Reddening
22.9: Correcting for the Effects of Interstellar Dust
22.10: Dust in Dark Clouds
22.11: Dust in Reflection Nebulae
22.12: Direct Samples? No Way
22.13: Shapes and Orientations: The Polarization of Light
22.14: Controlling the Grains: What Doesn't Work
22.15: Controlling the Grains: What Does Work
22.16: The Composition of the Grains
23. Gas in the ISM
23.1: A Point-Form Summary
23.2: Associated Readings from the Text
23.3: So Much For Dust: How About the Gas?
23.4: Gas in Cool Clouds: Absorption
23.5: Gas in Hot Clouds: Emission
23.6: New Instruments Yield New Insights
23.7: Radio Telescopes: The 21-cm Radiation of Neutral Hydrogen
23.8: Infrared Detectors: Star Formation
23.9: Millimeter-wave Detectors: Interstellar Molecules Again
24. The Size and Shape of Our Galaxy
24.1: A Point-Form Summary
24.2: Associated Readings from the Text
24.3: Observable Features and Obvious Questions
24.4: Our Place in the Milky Way
24.5: A Serious Objection
24.6: Herschel's Star Counts
24.7: The Kapteyn Universe
24.8: Shapley and the Globulars
24.9: The Flattening of the Milky Way
24.10: The Structure of the Milky Way
24.11: When and How Did the Milky Way Form?
24.12: The Motions of the Globular Clusters
24.13: Summary
25. The Discovery of External Galaxies
25.1: A Point-Form Summary
25.2: Associated Readings from the Text
25.3: What Are They?
25.4: Cepheid Variables
25.5: What Are Cepheids Doing, and Why?
25.6: The Period-Luminosity Relationship
25.7: Determining Distances with Cepheids: Mixed Blessings
25.8: The Great Debate
25.9: Shapley versus Hubble
26. Galaxies of All Kinds
26.1: A Point-Form Summary
26.2: Associated Readings from the Text
26.3: Spreading the Net
26.4: Hubble's Tuning Fork
26.5: Evolution? What's the Evidence?
26.6: The Masses of Galaxies: Dark Matter
26.7: Galaxy Interactions
26.8: The Cross-Sections of Galaxies
26.9: Mergers
26.10: The Distribution of Galaxies: Conurbations
26.11: One Big Difference
26.12: The Local Group
26.13: Nearby Clusters
26.14: Larger-Scale Structure
27. The Expanding Universe
27.1: A Point-Form Summary
27.2: Associated Readings from the Text
27.3: Hubble's Discovery
27.4: The Cosmological Principle
27.5: Uniform Expansion
27.6: Opportunities Missed
27.7: Olbers' Paradox
27.8: Einstein's Missed Opportunity
27.9: Hubble Anticipated
27.10: Einstein's Solution
28. Quasars and Active Galaxies
28.1: A Point-Form Summary
28.2: Associated Readings from the Text
28.3: The Interpretation of Redshift
28.4: Radio Sources
28.5: Enter the Moon
28.6: Back to Astrophysics
28.7: Maarten Schmidt's Discovery
28.8: ...and the Problem
28.9: No Lack of Imagination
28.10: Some Simple Predictions
28.11: A Growing Understanding
29. The Hot Big Bang
29.1: A Point-Form Summary
29.2: Associated Readings from the Text
29.3: The `Expansion Age' of the Universe
29.4: Hubble's Answer
29.5: Why Not the Big Bang?
29.6: Gamow's Speculations
29.7: Interest Lost and Regained
29.8: Serendipity Again
29.9: Let There Be Light
30. The Geometry of the Universe
30.1: A Point-Form Summary
30.2: Associated Readings from the Text
30.3: No Centre
30.4: An Infinite Universe
30.5: A Finite Universe
30.6: Curvature in the Universe
30.7: Measuring the Curvature of a Globe
30.8: Measuring the Curvature of the Universe
30.9: How Mass Determines the Geometry and the Fate of the Universe
30.10: Measure the Local Density
30.11: Measure the Slowdown
30.12: The Likely Future
30.13: Why We Believe in the Big Bang
31. Closing Thoughts
31.1: A Point-Form Summary
31.2: Associated Readings from the Text
31.3: Motivation
31.4: The Present Structure
31.5: The Growth of Structure
31.6: Why So Uniform?
31.7: Inflation
31.8: Back to the Future
31.9: Supernovae
31.10: The Surprising Result
31.11: Absolutely Final Remarks
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