The Feynman Lectures on Physics

The Feynman Lectures on Physics

The Feynman Lectures on Physics, Volume I
mainly mechanics, radiation, and heat
(single-column Table of Contents)
About the Authors
Preface to the New Millennium Edition
Feynman’s Preface

Chapter 1. Atoms in Motion
  1-1 Introduction
  1-2 Matter is made of atoms
  1-3 Atomic processes
  1-4 Chemical reactions

Chapter 2. Basic Physics
  2-1 Introduction
  2-2 Physics before 1920
  2-3 Quantum physics
  2-4 Nuclei and particles

Chapter 3. The Relation of Physics to Other Sciences
  3-1 Introduction
  3-2 Chemistry
  3-3 Biology
  3-4 Astronomy
  3-5 Geology
  3-6 Psychology
  3-7 How did it get that way?

Chapter 4. Conservation of Energy
  4-1 What is energy?
  4-2 Gravitational potential energy
  4-3 Kinetic energy
  4-4 Other forms of energy

Chapter 5. Time and Distance
  5-1 Motion
  5-2 Time
  5-3 Short times
  5-4 Long times
  5-5 Units and standards of time
  5-6 Large distances
  5-7 Short distances

Chapter 6. Probability
  6-1 Chance and likelihood
  6-2 Fluctuations
  6-3 The random walk
  6-4 A probability distribution
  6-5 The uncertainty principle

Chapter 7. The Theory of Gravitation
  7-1 Planetary motions
  7-2 Kepler’s laws
  7-3 Development of dynamics
  7-4 Newton’s law of gravitation
  7-5 Universal gravitation
  7-6 Cavendish’s experiment
  7-7 What is gravity?
  7-8 Gravity and relativity

Chapter 8. Motion
  8-1 Description of motion
  8-2 Speed
  8-3 Speed as a derivative
  8-4 Distance as an integral
  8-5 Acceleration

Chapter 9. Newton’s Laws of Dynamics
  9-1 Momentum and force
  9-2 Speed and velocity
  9-3 Components of velocity, acceleration, and force
  9-4 What is the force?
  9-5 Meaning of the dynamical equations
  9-6 Numerical solution of the equations
  9-7 Planetary motions

Chapter 10. Conservation of Momentum
  10-1 Newton’s Third Law
  10-2 Conservation of momentum
  10-3 Momentum is conserved!
  10-4 Momentum and energy
  10-5 Relativistic momentum

Chapter 11. Vectors
  11-1 Symmetry in physics
  11-2 Translations
  11-3 Rotations
  11-4 Vectors
  11-5 Vector algebra
  11-6 Newton’s laws in vector notation
  11-7 Scalar product of vectors

Chapter 12. Characteristics of Force
  12-1 What is a force?
  12-2 Friction
  12-3 Molecular forces
  12-4 Fundamental forces. Fields
  12-5 Pseudo forces
  12-6 Nuclear forces

Chapter 13. Work and Potential Energy (A)
  13-1 Energy of a falling body
  13-2 Work done by gravity
  13-3 Summation of energy
  13-4 Gravitational field of large objects

Chapter 14. Work and Potential Energy (conclusion)
  14-1 Work
  14-2 Constrained motion
  14-3 Conservative forces
  14-4 Nonconservative forces
  14-5 Potentials and fields

Chapter 15. The Special Theory of Relativity
  15-1 The principle of relativity
  15-2 The Lorentz transformation
  15-3 The Michelson-Morley experiment
  15-4 Transformation of time
  15-5 The Lorentz contraction
  15-6 Simultaneity
  15-7 Four-vectors
  15-8 Relativistic dynamics
  15-9 Equivalence of mass and energy

Chapter 16. Relativistic Energy and Momentum
  16-1 Relativity and the philosophers
  16-2 The twin paradox
  16-3 Transformation of velocities
  16-4 Relativistic mass
  16-5 Relativistic energy

Chapter 17. Space-Time
  17-1 The geometry of space-time
  17-2 Space-time intervals
  17-3 Past, present, and future
  17-4 More about four-vectors
  17-5 Four-vector algebra
Chapter 18. Rotation in Two Dimensions
  18-1 The center of mass
  18-2 Rotation of a rigid body
  18-3 Angular momentum
  18-4 Conservation of angular momentum

Chapter 19. Center of Mass; Moment of Inertia
  19-1 Properties of the center of mass
  19-2 Locating the center of mass
  19-3 Finding the moment of inertia
  19-4 Rotational kinetic energy

Chapter 20. Rotation in space
  20-1 Torques in three dimensions
  20-2 The rotation equations using cross products
  20-3 The gyroscope
  20-4 Angular momentum of a solid body

Chapter 21. The Harmonic Oscillator
  21-1 Linear differential equations
  21-2 The harmonic oscillator
  21-3 Harmonic motion and circular motion
  21-4 Initial conditions
  21-5 Forced oscillations

Chapter 22. Algebra
  22-1 Addition and multiplication
  22-2 The inverse operations
  22-3 Abstraction and generalization
  22-4 Approximating irrational numbers
  22-5 Complex numbers
  22-6 Imaginary exponents

Chapter 23. Resonance
  23-1 Complex numbers and harmonic motion
  23-2 The forced oscillator with damping
  23-3 Electrical resonance
  23-4 Resonance in nature

Chapter 24. Transients
  24-1 The energy of an oscillator
  24-2 Damped oscillations
  24-3 Electrical transients

Chapter 25. Linear Systems and Review
  25-1 Linear differential equations
  25-2 Superposition of solutions
  25-3 Oscillations in linear systems
  25-4 Analogs in physics
  25-5 Series and parallel impedances

Chapter 26. Optics: The Principle of Least Time
  26-1 Light
  26-2 Reflection and refraction
  26-3 Fermat’s principle of least time
  26-4 Applications of Fermat’s principle
  26-5 A more precise statement of Fermat’s principle
  26-6 How it works

Chapter 27. Geometrical Optics
  27-1 Introduction
  27-2 The focal length of a spherical surface
  27-3 The focal length of a lens
  27-4 Magnification
  27-5 Compound lenses
  27-6 Aberrations
  27-7 Resolving power

Chapter 28. Electromagnetic Radiation
  28-1 Electromagnetism
  28-2 Radiation
  28-3 The dipole radiator
  28-4 Interference

Chapter 29. Interference
  29-1 Electromagnetic waves
  29-2 Energy of radiation
  29-3 Sinusoidal waves
  29-4 Two dipole radiators
  29-5 The mathematics of interference

Chapter 30. Diffraction
  30-1 The resultant amplitude due to n equal oscillators
  30-2 The diffraction grating
  30-3 Resolving power of a grating
  30-4 The parabolic antenna
  30-5 Colored films; crystals
  30-6 Diffraction by opaque screens
  30-7 The field of a plane of oscillating charges

Chapter 31. The Origin of the Refractive Index
  31-1 The index of refraction
  31-2 The field due to the material
  31-3 Dispersion
  31-4 Absorption
  31-5 The energy carried by an electric wave
  31-6 Diffraction of light by a screen

Chapter 32. Radiation Damping. Light Scattering
  32-1 Radiation resistance
  32-2 The rate of radiation of energy
  32-3 Radiation damping
  32-4 Independent sources
  32-5 Scattering of light

Chapter 33. Polarization
  33-1 The electric vector of light
  33-2 Polarization of scattered light
  33-3 Birefringence
  33-4 Polarizers
  33-5 Optical activity
  33-6 The intensity of reflected light
  33-7 Anomalous refraction

Chapter 34. Relativistic Effects in Radiation
  34-1 Moving sources
  34-2 Finding the “apparent” motion
  34-3 Synchrotron radiation
  34-4 Cosmic synchrotron radiation
  34-5 Bremsstrahlung
  34-6 The Doppler effect
  34-7 The ω, k four-vector
  34-8 Aberration
  34-9 The momentum of light

Chapter 35. Color Vision
  35-1 The human eye
  35-2 Color depends on intensity
  35-3 Measuring the color sensation
  35-4 The chromaticity diagram
  35-5 The mechanism of color vision
  35-6 Physiochemistry of color vision
Chapter 36. Mechanisms of Seeing
  36-1 The sensation of color
  36-2 The physiology of the eye
  36-3 The rod cells
  36-4 The compound (insect) eye
  36-5 Other eyes
  36-6 Neurology of vision

Chapter 37. Quantum Behavior
  37-1 Atomic mechanics
  37-2 An experiment with bullets
  37-3 An experiment with waves
  37-4 An experiment with electrons
  37-5 The interference of electron waves
  37-6 Watching the electrons
  37-7 First principles of quantum mechanics
  37-8 The uncertainty principle

Chapter 38. The Relation of Wave and Particle Viewpoints
  38-1 Probability wave amplitudes
  38-2 Measurement of position and momentum
  38-3 Crystal diffraction
  38-4 The size of an atom
  38-5 Energy levels
  38-6 Philosophical implications

Chapter 39. The Kinetic Theory of Gases
  39-1 Properties of matter
  39-2 The pressure of a gas
  39-3 Compressibility of radiation
  39-4 Temperature and kinetic energy
  39-5 The ideal gas law

Chapter 40. The Principles of Statistical Mechanics
  40-1 The exponential atmosphere
  40-2 The Boltzmann law
  40-3 Evaporation of a liquid
  40-4 The distribution of molecular speeds
  40-5 The specific heats of gases
  40-6 The failure of classical physics

Chapter 41. The Brownian Movement
  41-1 Equipartition of energy
  41-2 Thermal equilibrium of radiation
  41-3 Equipartition and the quantum oscillator
  41-4 The random walk

Chapter 42. Applications of Kinetic Theory
  42-1 Evaporation
  42-2 Thermionic emission
  42-3 Thermal ionization
  42-4 Chemical kinetics
  42-5 Einstein’s laws of radiation

Chapter 43. Diffusion
  43-1 Collisions between molecules
  43-2 The mean free path
  43-3 The drift speed
  43-4 Ionic conductivity
  43-5 Molecular diffusion
  43-6 Thermal conductivity

Chapter 44. The Laws of Thermodynamics
  44-1 Heat engines; the first law
  44-2 The second law
  44-3 Reversible engines
  44-4 The efficiency of an ideal engine
  44-5 The thermodynamic temperature
  44-6 Entropy

Chapter 45. Illustrations of Thermodynamics
  45-1 Internal energy
  45-2 Applications
  45-3 The Clausius-Clapeyron equation

Chapter 46. Ratchet and pawl
  46-1 How a ratchet works
  46-2 The ratchet as an engine
  46-3 Reversibility in mechanics
  46-4 Irreversibility
  46-5 Order and entropy

Chapter 47. Sound. The wave equation
  47-1 Waves
  47-2 The propagation of sound
  47-3 The wave equation
  47-4 Solutions of the wave equation
  47-5 The speed of sound

Chapter 48. Beats
  48-1 Adding two waves
  48-2 Beat notes and modulation
  48-3 Side bands
  48-4 Localized wave trains
  48-5 Probability amplitudes for particles
  48-6 Waves in three dimensions
  48-7 Normal modes

Chapter 49. Modes
  49-1 The reflection of waves
  49-2 Confined waves, with natural frequencies
  49-3 Modes in two dimensions
  49-4 Coupled pendulums
  49-5 Linear systems

Chapter 50. Harmonics
  50-1 Musical tones
  50-2 The Fourier series
  50-3 Quality and consonance
  50-4 The Fourier coefficients
  50-5 The energy theorem
  50-6 Nonlinear responses

Chapter 51. Waves
  51-1 Bow waves
  51-2 Shock waves
  51-3 Waves in solids
  51-4 Surface waves

Chapter 52. Symmetry in Physical Laws
  52-1 Symmetry operations
  52-2 Symmetry in space and time
  52-3 Symmetry and conservation laws
  52-4 Mirror reflections
  52-5 Polar and axial vectors
  52-6 Which hand is right?
  52-7 Parity is not conserved!
  52-8 Antimatter
  52-9 Broken symmetries Have We Been Interpreting Quantum Mechanics Wrong This Whole Time? Have We Been Interpreting Quantum Mechanics Wrong This Whole Time?

The orthodox view of quantum mechanics, known as the “Copenhagen interpretation” after the home city of Danish physicist Niels Bohr, one of its architects, holds that particles play out all possible realities simultaneously. Each particle is represented by a “probability wave” weighting these various possibilities, and the wave collapses to a definite state only when the particle is measured. The equations of quantum mechanics do not address how a particle’s properties solidify at the moment of measurement, or how, at such moments, reality picks which form to take. But the calculations work.

A classic experiment in quantum mechanics that seems to demonstrate the probabilistic nature of reality involves a beam of particles (such as electrons) propelled one by one toward a pair of slits in a screen. When no one keeps track of each electron’s trajectory, it seems to pass through both slits simultaneously. In time, the electron beam creates a wavelike interference pattern of bright and dark stripes on the other side of the screen. But when a detector is placed in front of one of the slits, its measurement causes the particles to lose their wavelike omnipresence, collapse into definite states, and travel through one slit or the other. The interference pattern vanishes. The great 20th-century physicist Richard Feynman said that this double-slit experiment “has in it the heart of quantum mechanics,” and “is impossible, absolutely impossible, to explain in any classical way.”

The experiments began a decade ago, when Yves Couder and colleagues at Paris Diderot University discovered that vibrating a silicon oil bath up and down at a particular frequency can induce a droplet to bounce along the surface. The droplet’s path, they found, was guided by the slanted contours of the liquid’s surface generated from the droplet’s own bounces — a mutual particle-wave interaction analogous to de Broglie’s pilot-wave concept.

Leonard Susskind in Stanford: The Theoretical Minimum

Leonard Susskind in Stanford: The Theoretical Minimum

A number of years ago I became aware of the large number of physics enthusiasts out there who have no venue to learn modern physics and cosmology. Fat advanced textbooks are not suitable to people who have no teacher to ask questions of, and the popular literature does not go deeply enough to satisfy these curious people. So I started a series of courses on modern physics at Stanford University where I am a professor of physics. The courses are specifically aimed at people who know, or once knew, a bit of algebra and calculus, but are more or less beginners.

Open Exoplanet Catalogue

Open Exoplanet Catalogue
The Open Exoplanet Catalogue is a catalogue of all discovered extra-solar planets. It is a new kind of astronomical database, based on small text files and a distributed version control system. It is decentralized and completely open. Contribution and corrections are welcome. The Open Exoplanet Catalogue is furthermore the only catalogue that can correctly represent the orbital structure of planets in arbitrary binary, triple and quadruple star systems as well as orphan planets.

Periodic Table | Minute Physics

Periodic Table | Minute Physics

Hopefully you noticed the big temperature control at the top of the page. You can use it to see how elements behave at different temperatures. You can see either magnetic properties or states of matter by changing the title (in the top left) between “Magnetism” and “States”. There are also other settings you can access by clicking on the settings icon ( ).

Thanks to Periodic Videos, you can click on any of the elements to see an awesomely informative video about that element!

Magnetic Phase Transitions

As Henry explained in his video, matter can take on one of five magnetic states: Ferromagnetic, Antiferromagnetic, Paramagnetic, Diamagnetic, or Ferrimagnetic (we’re going to ignore that last one for now).

Some elements can change between ferromagnetic, antiferromagnetic, and paramagnetic by heating or cooling them. This is a lot like elements transition between solid, liquid, and gas. This “melting” of magnetic states generally happens in this order: ferromagnetic, antiferromagnetic, paramagnetic.

The ferromagnetic “melting” temperature is called the Curie Temperature (Tc), and the antiferromagnetic “melting” temperature is called the Néel temperature (Tn). Sometimes elements may change right from ferromagnetic to paramagnetic, others transition between all three, and others never become ferromagnetic or antiferromagnetic at all! On the possible existence of quark stars (with George Chapline) On the possible existence of quark stars (with George Chapline)
I received my Ph.D. in physics at Cornell under Hans Bethe in 1960. After a year and a half as a fellow at the Princeton Institute for Advanced Studies, I taught and did research in particle physics at Columbia and Stanford before coming in 1966 to the University of California at Santa Cruz. I was a founding member of its Physics Dept. initiating its program of particle and theoretical condensed matter physics. I retired from teaching in 1994 and now I am a Reseach Professor of Physics. My primary research interests have been in particle physics, condensed matter physics, astrophysics, and nonlinear dynamics. I also have had a long standing interest in the history of physics and mathematics, particularly during the 17-century, and I published articles on the works of Hooke, Newton and Huygens, and book reviews in this field. More recently I have written about more contemporary scientist like Poincare, Chandrasekhar and Stoner. I also have been in various activities which have brought

Google Europe Blog: Street View arrives at CERN

Google Europe Blog: Street View arrives at CERN
Street View arrives at CERN Thursday, September 26, 2013 | 12:30 PM Labels: Street View, Switzerland At CERN, the European particle physics laboratory based in the suburbs of Geneva, some of the world’s best physicists and engineers are using advanced particle accelerators to help solve age old questions about the universe — What is is made of? How did it start? We’re delighted that CERN opened its doors to Google Maps Street View allowing anyone, anywhere in the world to take a peek into its laboratories, control centers and its myriad underground tunnels housing cutting-edge experiments. Street View also lets scientists working on the experiments, who may be on the other side of the world, explore the equipment they’re using. Paul Lutus Paul Lutus
A site for people who think. Intellectual resources, programming, astronomy, science, mathematics, Java/JavaScript applets, programming instruction, home of Arachnophilia. Paul Lutus has a wide background in science and technology. He designed spacecraft components for the NASA Space Shuttle and created a mathematical model of the solar system used by the Jet Propulsion Laboratory during the Viking Mars mission. Then, at the beginning of the personal computer revolution, Lutus switched career paths and took up computer science. His best-known program is "Apple Writer," an internationally successful word processing program for the early Apple computers. In 1983 Reed College awarded Lutus the Vollum Award for Distinguished Accomplishment in Science and Technology, Oregon’s most prestigious academic honor. Other recipients of this award include Nobel Prizewinner Linus Pauling, Bill Gates, Steve Jobs, and Linus Torvalds. In 1986 the Oregon Academy of Science named Lutus "Outstanding Ore…

Physics Flash Animations

Physics Flash Animations
We have been increasingly using Flash animations for illustrating Physics content. This page provides access to those animations which may be of general interest. The animations will appear in a separate window.

The animations are sorted by category, and the file size of each animation is included in the listing. Also included is the minimum version of the Flash player that is required; the player is available free from The categories are:


Classical Mechanics

Electricity and Magnetism

Fluid Mechanics

Micrometer Caliper





Quantum Mechanics


Sound Waves



In addition, I have prepared a small tutorial in using Flash to do Physics animations. It contains screen shots and embedded Flash animations, so the file size is a 173k. You may view it in a separate window at