
The versions linked below supersede the published version (if any).
These works are a testament to my character as a "frog" in the sense of
Dyson (RiP, Feb. 28, 2020).
Does ∇ • J = 0 Imply ∇ • A = 0?
(Nov 11, 2022).
.ps version.
The SlidingBlock Problem in Various Inertial Frames
(Nov 7, 2022).
.ps version.
Relativistic Angular Momentum of a Spinning Disc
(Oct 29, 2022).
.ps version.
Special Relativity and the Precession of the Perihelion
(Oct 25, 2022).
.ps version.
Seppala's Paradox
(Oct 15, 2022).
.ps version.
ElectromagneticField Angular Momentum of a Classical Charged Particle in a Uniform Magnetic Field
(Sept 13, 2022).
.ps version.
Motion of a charged particle in the electric field of a uniformly charged finite wire,
Am. J. Phys. 90, 808 (2022),
(Sept 4, 2022).
A vectorial analysis of the "Golfer's Nemesis",
Am. J. Phys. 90, 807 (2022),
(Sept 4, 2022).
The RodRing Paradox
(Aug 3, 2022).
.ps version.
Field Energy of Two Spheres in Contact
(July 25, 2022).
.ps version.
Can 1^{z} = 2 for Complex z?
(July 22, 2022).
.ps version.
Can a Static
Transmission Line Be a Source of Infinite Power?
(July 9, 2022).
.ps version.
"Backflow" in the Interference of Two Electromagnetic
Plane Waves
(June 15, 2022).
.ps version.
Constant Acceleration and the Equivalence Principle
(May 10, 2022).
.ps version.
Breakdown of a Misinterpretation of Noether's Theorem
(Mar 23, 2022).
.ps version.
For a more compact version, see Am. J. Phys. 90, 407 (2022).
Potentials for an Electromagnetic Plane Wave
(Mar 6, 2022).
.ps version.
A Misuse of "Maxwell Theory"
(Feb 10, 2022).
.ps version.
The Field Momentum of Two TimeDependent Dipoles
(Feb 4, 2022).
.ps version.
See also Am. J. Phys. 90, 247 (2022).
A RollingCylinder Problem
(Jan 18, 2022).
.ps version.
Transition Radiation at a MetalVacuum Interface
and at the Interface between Two Dielectrics
(Dec 8, 2021).
.ps version.
Nonlinear, Strong Field QED: SLAC Experiment
E144,
(ExHILP21, Jena, Sept 17, 2021).
.pptx version.
Helmholtz' Influence on The Mikado by Gilbert and Sullivan
(Aug 25, 2021).
.ps version.
Counterintuitive Performance of Land and Sea Yachts
(July 22, 2021).
.ps version.
Classical Electromagnetic Fields of a Pair of Annihilating Charges
(June 11, 2021).
.ps version.
An Alternative Magnetic Field Based on Ampère's Force Law,
with Chananya Groner and Tim Minteer
(May 11, 2021).
.ps version.
Helmholtz' Vector Potentials
(May 8, 2021).
.ps version.
The HooperMonstein Paradox
(May 3, 2021).
.ps version.
Marinov's Paradoxical Motor
(Apr 30, 2021).
.ps version.
Dumbell in Orbit
(Apr 9, 2021).
.ps version.
Notes on the Dirac Equation
(Mar 3, 2021).
.ps version.
Regarding the energy Lorentz transformation of classical particles and waves bouncing in a box,
William Celmaster (Jan 10, 2021).
∇ × (∇ × E) in Spherical Coordinates,
with V. Onoochin (Dec 21, 2020).
.ps version.
Temperature and Special Relativity
(Dec 2, 2020).
.ps version.
Electric Flux of an Accelerated Charge
(Nov 14, 2020).
.ps version.
Feynman Diagrams by Wentzel (1938)
(Oct 6, 2020).
.ps version.
Time Dilation of Moving Clocks as a Consequence of Length Contraction
(Sept 30, 2020).
.ps version.
Equal Radiation Frequencies from Different Transitions in Hydrogen Atoms,
Trung V Phan and Kim Tuan Do
(Aug 28, 2020).
.ps version.
Graneau's Electromagnetic Submarine,
(Aug 1, 2020).
.ps version.
Mertz' Paramagnetic Fluid Pump
(July 28, 2020).
.ps version.
Weber's Electrodynamics and the Hall Effect
(June 5, 2020).
.ps version.
Could Electrons Be Black Holes?
(May 28, 2020).
.ps version.
Another Circuit Paradox of Hering
(Mar 7, 2020).
.ps version.
Force and Torque while Frying an Egg
(Feb 27, 2020).
.ps version.
"Hidden" Momentum in an Isolated Brick?
(Feb 14, 2020).
.ps version.
"Hidden" Momentum in a Compressed Rod?
(Feb 11, 2020).
.ps version.
Engelhardt's Electromagnetic Spaceship
(Feb 5, 2020).
.ps version.
The Clock Paradox and Accelerometers
(Jan 11, 2020).
.ps version.
A Misuse of Relativity in Circuit Analysis
(Oct 23, 2019).
.ps version.
Is Faraday's Disk Dynamo a FluxRule Exception?
(July 27, 2019).
.ps version.
With a long Appendix on the history of magnetism to the time of Maxwell.
Does Centrifugal Force Affect Conduction Electrons?
(June 25, 2019).
.ps version.
TwoDimensional Multipole Magnets
(June 11, 2019).
.ps version.
Comments on Torque Analyses
(Apr 28, 2019).
.ps version.
The Relativity of Acceleration
(Apr 3, 2019).
.ps version.
Snowball/Log Rolling down a Snowy Slope,
(Mar 12, 2019).
.ps version.
Comment on "A variablemass snowball rolling down a snowy slope",
Phys. Teach. 57, 436 (2019).
Two Observers of Schrödinger's Cat,
(Mar 3, 2019).
.ps version.
Hering's FluxLinkage Paradox,
(Feb 25, 2019).
.ps version.
McClymer's Electromagnetic Spaceship,
(Feb 23, 2019).
.ps version.
Marinov's Magnetic Puzzler,
(Jan 14, 2019).
.ps version.
The Electric Self Force on a Current Loop,
(Jan 8, 2019).
.ps version.
Reactor Neutrino Experiments,
XII SILSAFAE@Lima
(Nov 27, 2018).
.pptx version.
Fields in a Coaxial Cable with a DC Current,
(Oct 25, 2018).
.ps version.
Energy Balance while Charging a Capacitor,
(Oct 21, 2018).
.ps version.
No Bootstrap Spaceships via Magnets in Electric
Fields,
short version (Aug 16, 2018).
.ps version.
No Bootstrap Spaceships,
longer review (Aug 9, 2018).
.ps version.
Alternative Forms of the Poynting Vector,
(July 13, 2018).
.ps version.
Gravitational Interaction between FastMoving
Particles,
(June 24, 2018).
.ps version.
Uncoiling on a Horizontal Surface,
(June 2, 2018).
.ps version.
Torricelli's Law for Large Holes,
with J. Otto
(May 15, 2018).
.ps version.
Leaky Bucket Suspended by a Spring,
with J. Otto (May 7, 2018).
.ps version.
What is the Stiffness of Spacetime?
(Apr 13, 2018).
.ps version.
Helmholtz and the Velocity Gauge,
with an appendix on the history of potentials.
(Mar 31, 2018).
.ps version.
Recombining Rainbows
(Feb 28, 2018), Letter to
The Physics Teacher
commenting on
Phys. Teach. 56, 14 (2018).
Radiation Damping of a Refrigerator Magnet
(Jan 20, 2018).
.ps version.
Motion of a Cylinder Tied to a Slope by a String
(Jan 12, 2018).
.ps version.
Avril's Radiation Problem
(Jan 4, 2018).
.ps version.
Pendulum in Orbit
(Dec 1, 2017).
.ps version.
Buquoy's Problem: Lifting a String from a Table
(Nov 29, 2017).
.ps version.
A Falling, Folded String
(Nov 28, 2017).
.ps version.
An AtmosphericDensity Anomaly with a Magnetostatic Analog,
with N.E. Tarshish
(Nov 14, 2017).
.ps version.
A SlidingBlock Problem
(Nov 7, 2017).
.ps version.
Fields inside a Sphere and Shell of Uniform
Polarization
(Oct 31, 2017).
.ps version.
The Radiation Reaction during the
Collapse of a Classical Electric Dipole
(Aug 24, 2017).
.ps version.
Nahin's Bobsled
(July 19, 2017).
.ps version.
Rayleigh's Spinning Ring
(July 12, 2017).
.ps version.
Slepian's FasterThanLight Wave
(June 23, 2017).
.ps version.
Can the Field Lines of a Permanent Magnet
Be Tied in Knots?
(June 12, 2017).
.ps version.
Field and Kinetic Energies
of a Pair of Permanent Magnetic Dipoles
(May 21, 2017).
.ps version.
On the History of the Radiation Reaction
(May 6, 2017).
.ps version.
Little's Paradox
(Apr 21, 2017).
.ps version.
Radiative Energy Transfer with Filters and
Stokes/AntiStokes Coatings
(Mar 29, 2017).
.ps version.
Energy Conservation in a Pulley + Mass System
(Jan 31, 2017).
.ps version.
Rotational Stability of a Diamagnetic Rod
(Jan 18, 2017).
.ps version.
Vector Potential of a Long Solenoid
in the Poincaré Gauge
(Jan 15, 2017).
.ps version.
Can an Electric Current Density Be Replaced
by an Equivalent Magnetization Density?
(Jan 5, 2017).
.ps version.
Forces on Halves of a Uniformly Magnetized Sphere
(Dec 23, 2016).
.ps version.
Electromagnetic SelfForce on a Hemispherical
Cavity
(Nov 27, 2016).
.ps version.
Antigravity, ElectronPositron Storage Rings,
and the K0K0bar System
(Oct 28, 2016).
.ps version.
The BrownTwiss RadioWave Interferometer
(Oct 8, 2016).
.ps version.
Does ChargedPion Decay Violate
Conservation of Angular Momentum?
(Sept 6, 2016).
.ps version.
Past Experiments Exclude Light Majorana Neutrino States,
with U Akhouri
(Aug 11, 2016).
.ps version.
Seminar
(Mar 7, 2017).
.pptx version.
Poster at Lepton/Photon 2017
(Aug, 2017).
.pptx version of poster.
5minute summary
(Aug 11, 2017).
.pptx version.
Does Space Charge or the Dielectric Constant
Affect Induced Charge in a Liquid Argon Detector?
(June 4, 2016).
.ps version.
Charging of an Insulator in a Liquid Argon Detector
(May 26, 2016).
.ps version.
(Non)decoherence in the Daya Bay Reactor
Antineutrino Experiment
(May 20, 2016).
.ps version.
Gravitational Acceleration of a Moving Object
at the Earth's Surface
(Apr 4, 2016). Includes an Appendix on the stability of circular orbits near a black hole, as relevant to the gravitational radiation from binary blackhole mergers recently observed by LIGO,
.ps version.
Slab Rolling on a Rolling Cylinder
(Mar 28, 2016).
.ps version.
Force between Two Uniformly Magnetized Spheres
(Mar 23, 2016).
.ps version.
Rotating Water Bucket with Lid
(Mar 12, 2016).
.ps version.
HydrogenAtom Wavefunctions as Radiationless
Modes
(Mar 11, 2016).
.ps version.
Electromagnetic Helicopter?
(Jan 25, 2016).
.ps version.
Ampère's Hairpin Spaceship
(Jan 16, 2016).
.ps version.
Can Magnetic Field Lines Break and Reconnect?
(Dec 29, 2015).
.ps version.
CapacitorDriven Railgun: Magnetic Fields Doing Work
(Dec 28, 2015).
.ps version.
Electromagnetic Fields inside a Perfect Conductor
(Dec 24, 2015).
.ps version.
Why Doesn't a Picture Hang Straight?
(Dec 9, 2015).
.ps version.
Tuval's Electromagnetic Spaceship
(Nov 30, 2015).
.ps version.
Dineutrons
(June 22, 2015).
.ps version.
A Damped Oscillator as a Hamiltonian System
(June 9, 2015).
.ps version.
Comay's Paradox: Do Magnetic Charges Conserve
Energy?
(June 1, 2015).
.ps version.
Electromagnetic Angular Momentum
of a Rotating Cylindrical Shell of Charge,
(May 26, 2015).
.ps version.
Laplace and the Speed of Gravity,
(May 5, 2015).
.ps version.
"Hidden" Momentum in an e+e Pair,
(Apr 30, 2015).
.ps version.
Birkeland, Darboux and Poincaré: Motion of an
Electric Charge in the Field of a Magnetic Pole,
(Apr 15, 2015).
.ps version.
"Hidden" Momentum in a Charged, Rotating Cylinder,
(Apr 6, 2015).
.ps version.
Potentials for a Hertzian Oscillating
Dipole,
(Apr 6, 2015).
.ps version.
"Hidden" Momentum in a Magnetized Toroid,
(Mar 29, 2015).
.ps version.
Pressure in Fluid Flow Past a Sphere,
(Mar 19, 2015).
.ps version.
Formal Expressions for the Electromagnetic Potentials
in Any Gauge,
with HK Yang (Feb 25, 2015).
.ps version.
Bibliography on the AbrahamMinkowski Debate
(Feb 17, 2015).
.ps version.
Pulses and 1/f Noise
(Jan 24, 2015).
.ps version.
Electromagnetic Field Angular Momentum
of a Charge at Rest in a Uniform Magnetic Field
(Dec 21, 2014).
.ps version.
Index of Refraction of a Moving Medium
(Dec 17, 2014).
.ps version.
YoYo Variants
(Nov 25, 2014).
.ps version.
Heat Flow from a Point Source at the End of a Bar
(Nov 18, 2014).
.ps version.
Forces on Magnetic Dipoles
(Oct 26, 2014).
.ps version.
Cylinder Rolling inside Another Rolling Cylinder
(Oct 23, 2014).
.ps version.
Rolling Water Pipe
(Oct 10, 2014).
.ps version.
Waves on a Mismatched Transmission Line
(Oct 4, 2014).
.ps version.
Cylinder Rolling on Another Rolling Cylinder
(Oct 2, 2014).
.ps version.
Electrodynamics in 1 and 2 Spatial Dimensions
(Sept 23, 2014).
.ps version.
Expanding Spherical Shell of Charge
(Aug 22, 2014).
.ps version.
Fields of a Uniformly Accelerated Charge, with
V. Onoochin (Aug 19, 2014).
.ps version.
Leaky Syringe
(Aug 10, 2014).
.ps version.
Backtracking of Charged Particles in a Magnetic Field
(Aug 6, 2014).
.ps version.
Error Estimation in Fitting of Ellipses
(July 17, 2014).
Electric and Magnetic Hoses
(July 16, 2014).
.ps version.
Jefimenko's Wedge Circuit
(July 8, 2014).
.ps version.
Hydraulic Brake
(June 26, 2014).
Maxwell and Special Relativity,
with an appendix on Maxwell's development of his theory of electromagnetism.
(May 26, 2014).
.ps version.
Force between Two Comoving Electric Charges
(May 24, 2014).
.ps version.
J.J. Thomson and "Hidden" Momentum
(Apr 30, 2014).
.ps version.
Conversions of D and H between SI and Gaussian Units
(Apr 12, 2014).
.ps version.
Does Destructive Interference Destroy Energy?
(Jan 7, 2014).
.ps version.
Wireless Power Transmission
(Dec 27, 2013).
.ps version.
Wedgefall
(Dec 6, 2013).
.ps version.
Classical Aspects of the AharonovBohm Effect
(Nov 29, 2013).
.ps version.
Canoe ± Rock
(Nov 9, 2013).
.ps version.
Notes on Fermi's Golden Rule
(Oct 16, 2013).
Rain and Relativity
(Oct 10, 2013).
.ps version.
Can Salmon Swim up a Waterfall after Leaping into It?
(Sept 17, 2013).
.ps version.
"Hidden" Momentum in a Leaping Beaded Chain?
(Aug 19, 2013).
.ps version.
Do Neutrino Oscillations Conserve Energy?
(July 21, 2013).
.ps version.
.pdf slides.
A Simplified View of the Higgs/Yukawa Mechanism
(July 17, 2013).
.ps version.
Angular Momentum in Circular Waveguides
(June 29, 2013).
.ps version.
729 Variants of Poynting's Theorem
(May 21, 2013).
.ps version.
BiotSavart vs. EinsteinLaub Force Law
(May 21, 2013).
.ps version.
An Electric Bottle:
Charged Particle Orbiting a Charged Needle
(May 1, 2013).
.ps version.
Relativistic Harmonic Oscillator
(Apr 28, 2013).
.ps version.
"Hidden Momentum" in an Unbalanced Tire?
(Apr 20, 2013).
.ps version.
What is i^{i}?
(Mar 30, 2013).
.ps version.
Poynting's Theorem with Magnetic Monopoles
(Mar 23, 2013).
Includes Appendix D.1 on the history of electromagnetic duality.
.ps version.
Self Inductance of a Solenoid
with a Permanent Magnet Core
(Mar 3, 2013).
.ps version.
Entropy Generation in the Merging of Two Ideal
Gases
(Feb 27, 2013).
.ps version.
Power in a Variable Capacitor
(Feb 26, 2013).
.ps version.
Momentum of a Charged Particle
Orbiting a Magnetic Dipole
(Feb 25, 2013).
.ps version.
Maximum Power from DC Current and Voltage Sources
(Feb 18, 2013).
.ps version.
Spherical Capacitor with Anisotropic
Permeability
(Feb 13, 2013).
.ps version.
Are Christoffel Symbols Needed to Analyze
Transient Phenomena in Faraday's Dynamo?
(Feb 12, 2013).
.ps version.
Does Transmission of Light through a Window
Involve Physics at the Planck Scale?
(Feb 4, 2013).
.ps version.
A Reflecting Polarizer as a Quantum Watchdog
(Dec 23, 2012).
.ps version.
Intensity, Brightness and Étendue of an Aperture
Lamp
(Dec 8, 2012).
.ps version.
From Fick's Law to the Mean Free Path
(Dec 5, 2012).
.ps version.
Bernoulli's Equation for a Rotating Fluid
(Nov 29, 2012).
.ps version.
Oscillating Fluid in a UTube
(Nov 28, 2012).
.ps version.
Stability of Transverse Oscillations in a
Betatron
(Nov 26, 2012).
.ps version.
Rolling Off a Log with Friction
(Nov 26, 2012).
.ps version.
Skiing on a Cosine Hill
(Nov 25, 2012).
.ps version.
"Skiing" is the only common English word that contains "ii".
Ladder + Rope
(Nov 21, 2012).
.ps version.
Electric Field Distribution in a ReverseBiased pn
Junction
(Nov 17, 2012).
.ps version.
Unipolar Induction via a Rotating Magnetized Sphere
(Nov 13, 2012).
.ps version.
The Pin and the Pendulum
(Oct 30, 2012).
.ps version.
Rocket Car
(Oct 1, 2012).
.ps version.
Voltage Drop, Potential Difference and EMF
(Sep 12, 2012).
.ps version.
Center of Mass of a Relativistic Rolling Hoop
(Sep 7, 2012).
.ps version.
Potentials of a Hertzian Dipole in the Gibbs Gauge
(Aug 23, 2012).
.ps version.
"Hidden" Momentum in a Linked Pair of Gyrostats?
(Aug 17, 2012).
.ps version.
"Hidden" Momentum in a Spinning Sphere?
(Aug 16, 2012).
.ps version.
On the Definition of "Hidden" Momentum
(July 9, 2012).
.ps version.
"Hidden" Momentum in an Oscillating Spring?
(July 8, 2012).
.ps version.
"Hidden" Momentum in a Plane Electromagnetic Wave?
(July 7, 2012).
.ps version.
"Hidden" Momentum in a River?
(July 5, 2012).
.ps version.
"Hidden" Momentum in a Current Loop
(June 30, 2012).
.ps version.
"Hidden" Momentum in a Set of Circulating Rockets?
(June 29, 2012).
.ps version.
"Hidden" Momentum in a Link of a Moving Chain?
(June 28, 2012).
.ps version.
"Hidden" Momentum in an Oscillating Tube of Water?
(June 24, 2012).
.ps version.
Abraham, Minkowski and "Hidden" Mechanical Momentum
(June 6, 2012).
.ps version.
Maxwellian Vacuum Polarization
(June 2, 2012).
.ps version.
Mansuripur's Paradox
(May 2, 2012).
.ps version.
Magnetic Damping
(Apr 14, 2012).
.ps version.
Circuit Q and Field Energy
(Apr 1, 2012).
.ps version.
Motion of a Pair of Oppositely Charged Spheres
(Feb 3, 2012).
.ps version.
Sommerfeld's Diffraction Problem
(Jan 22, 2012).
.ps version.
Babinet's Principle for Electromagnetic Fields,
with Z.M. Tan (Jan 19, 2012).
.ps version.
Symmetries of Electromagnetic Fields
Associated with a Plane Conducting Screen,
with Z.M. Tan (Jan 14, 2012).
.ps version.
A Gentler LooptheLoop
(Jan 7, 2012).
.ps version.
What is the Role of the Arms of a Linear Broadcast
Antenna?
(Dec 19, 2011).
.ps version.
Fields and Moments of a Moving Electric Dipole,
with V. Hnizdo
(Nov 29, 2011).
.ps version.
Energy Flow in a Transformer
(Nov 15, 2011).
.ps version.
Slingshot Ride
(Nov 13, 2011).
.ps version.
Resistive Cylinder in an External,
Static Magnetic Field
(Nov 2, 2011).
.ps version.
Small Oscillations of a Mass That Slides inside a Cylinder
Which Rotates about a Horizontal Axis
(Nov 1, 2011).
.ps version.
Perfectly Conducting Cylinder in an External,
Static Magnetic Field
(Oct 29, 2011).
.ps version.
Wagon in the Rain
(Oct 22, 2011).
.ps version.
Box Toss
(Oct 17, 2011).
.ps version.
Scattering of a Plane Electromagnetic Wave
by a Small Conducting Cylinder
(Oct 4, 2011).
.ps version.
Wire Polarizers
(Sep 21, 2011).
.ps version.
ForceFree Magnetic Fields aka Eigenfunctions of the
Curl Operator
(Aug 10, 2011).
.ps version.
Information Channel Capacity
(July 23, 2011).
.ps version.
Power Consumption by a Pulsed Copper Magnet
(July 16, 2011).
.ps version.
Electromagnetic Plane Wave Expansion of Transition Radiation
(July 14, 2011).
.ps version.
Excitation of a Rectangular Electromagnetic Cavity
by a Passing, Relativistic Particle
(June 30, 2011).
.ps version.
An IllPosed Problem in RigidBody Dynamics
(June 11, 2011).
.ps version.
The Equivalence Principle and Roundtrip Times for Light
(May 25, 2011).
.ps version.
BallBearing Motor
(May 17, 2011).
.ps version.
Magnetic Forces Can Do Work
(Apr 10, 2011).
.ps version.
Spin and Orbital Angular Momentum of the Fields of
a Turnstile Antenna
(Apr 9, 2011).
.ps version.
Emittance Growth from Weak Relativistic Effects
(Mar 21, 2011).
.ps version.
Hamiltonian with z as the Independent Variable
(Mar 19, 2011).
.ps version.
Static Magnetic Field as Determined by Its Value on a
Surface
(Mar 17, 2011).
.ps version.
Expansion of an Axially Symmetric, Static
Magnetic Field in Terms of Its Axial Field
(Mar 10, 2011).
.ps version.
Potentials for a Cylindrical Electromagnetic
Cavity,
with J. Gallardo
(Mar 9, 2011).
.ps version.
Poincaré Potentials for a Finite Solenoid
(Mar 8, 2011).
.ps version.
Potentials for a Rectangular Electromagnetic Cavity
(Mar 4, 2011).
.ps version.
Charge Density in a CurrentCarrying Wire
(Dec 23, 2010).
.ps version.
Reactance of a Sinusoidally Driven Antenna
(Nov 15, 2010).
.ps version.
Ĉerenkov Radiation from a Short Path
(Oct 5, 2010).
.ps version.
Radiation by a TimeDependent Current Loop
(Sep 26, 2010).
.ps version.
On the Definition of Radiation by a System of
Charges
(Sep 6, 2010).
.ps version.
Decomposition of Electromagnetic Fields into
Electromagnetic Plane Waves
(July 11, 2010).
.ps version.
FitzGerald's Calculation of the Radiation of an
Oscillating Magnetic Dipole
(June 20, 2010).
.ps version.
Displacement Current of a Uniformly Moving Charge
(June 15, 2010).
.ps version.
Blondel's Experiment
(June 11, 2010).
.ps version.
Does the Moon Always Fall Towards the Sun?
(June 9, 2010).
.ps version.
Is There a Maximum Z for an Atom?
(June 2, 2010).
.ps version.
Analysis of TEM Waves in a Coaxial Cable
via the Scalar Potential
(May 12, 2010).
.ps version.
Lewin's Circuit Paradox
(May 7, 2010).
.ps version.
Doubly Negative Metamaterials
(Apr 14, 2010).
.ps version.
Can Sheared Surfaces Emit Light?
(Apr 9, 2010).
.ps version.
An Antenna Reciprocity Theorem
(Apr 3, 2010).
.ps version.
Image Method for an Electric Charge above a
Topological Insulator with a Quantum Hall Surface
(Jan 14, 2010).
.ps version.
Accelerating Through a Resonance on a "Washboard"
Road
(Dec 13, 2009).
The Appendix discusses an analogy between the Higgs mechanism and a washboard road.
.ps version.
Spinning Lasso,
with C.G. Tully (Dec 11, 2009).
.ps version.
Radiation from the Open End of a Coaxial Cable
(Dec 2, 2009).
.ps version.
Power Received by a Small Antenna
(Dec 1, 2009).
.ps version.
Dielectric (and Magnetic) Image Methods
(Nov 21, 2009).
.ps version.
Maxwell's Objection to Lorenz' Retarded Potentials
(Oct 26, 2009).
.ps version.
Kinetic Energy of Conduction Electrons in the Drude Model
(Oct 10, 2009).
.ps version.
Radiation Pressure of a Monochromatic Plane Wave on a
Flat Mirror
(Oct 10, 2009).
Section 3.1 relates the kinetic energy of conduction electrons to the imaginary part of the conductivity in the Drude model.
.ps version.
Reflection of a Gaussian Optical Beam by a Flat Mirror
(Oct 5, 2009).
.ps version.
Is Bernoulli's Equation Relativistically
Invariant?
(Sep 13, 2009).
.ps version.
How Much of Magnetic Energy is Kinetic Energy?
(Sep 12, 2009).
.ps version.
Lorentz Invariance of the Number of Photons in a
Rectangular Cavity
(July 28, 2009).
.ps version.
Electric Field of a Uniform Charge Density
(July 27, 2009).
.ps version.
Charged, Conducting, Rotating Sphere
(July 22, 2009).
.ps version.
SecondOrder Paraxial Gaussian Beam
(July 8, 2009).
.ps version.
Total and Frustrated Reflection of a Gaussian Optical
Beam
(July 7, 2009).
.ps version.
Reactance of Small Antennas
(June 3, 2009).
.ps version.
Energy Flow in a Waveguide below Cutoff
with M. Moriconi (May 20, 2009).
.ps version.
"Hidden" Momentum of a Steady Current Distribution in
a System at "Rest"
(Apr 21, 2009).
.ps version.
Orbital and Spin Angular Momentum of Electromagnetic
Fields
(Mar 12, 2009).
.ps version.
Charging a Capacitor via a Transient RLC Circuit
(Mar 6, 2009).
.ps version.
LowFrequency Electromagnetic Waves on a TwistedPair
Transmission Line (Dec 24, 2008).
.ps version.
Electromagnetic Fields of a Small Helical Toroidal
Antenna (Dec 8, 2008).
.ps version.
Classical Diamagnetism and the Satellite
Paradox (Nov 12, 2008).
.ps version.
Darwin Energy Paradoxes
(Oct 29, 2008).
.ps version.
Air Hockey Bowling
(Oct 17, 2008).
.ps version.
Can Dipole Antennas Above a Ground Plane Emit
Circularly Polarized Radiation? (Sep 19, 2008).
.ps version.
Radiation of Turnstile Antennas Above a Conducting
Ground Plane (Sep 18, 2008).
.ps version.
Charged, CounterRotating Disks on a Rotating
Platform, with C.T. Ridgely (Sep 11, 2008).
.ps version.
Faraday Rotation (Aug 28, 2008).
.ps version.
Unipolar Induction via a Rotating Magnetized
Cylinder (August 17, 2008).
.ps version.
Electrodynamics of Rotating Systems
(August 8, 2008).
.ps version.
The WilsonWilson Experiment
(July 31, 2008).
.ps version.
Magnetic Field at the Center of a Grounded,
Conducting Sphere Circled by a Moving Charge Q, with J. Castro
(June 26, 2008).
.ps version.
The Helmholtz Decomposition and the Coulomb Gauge
(Apr 17, 2008).
.ps version.
StaticVoltage Gauge
(Mar 25, 2008).
.ps version.
What Does an AC Voltmeter Measure?
(Mar 16, 2008).
.ps version.
Velocity Factor of an Insulated TwoWire
Transmission Line,
(Mar 7, 2008).
.ps version.
.xls velocity factor calculator.
Electron Trajectories in a Hall Thruster,
(Feb 27, 2008).
.ps version.
Exact and GeometricalOptics Energy
Trajectories in Twisted Beams, with Michael Berry
(Jan 15, 2008).
J. Opt. A 10, 03505 (2008).
Flow of Energy from a Localized Source in a Uniform,
Anisotropic Medium,
(Dec 8, 2007). .ps version.
Thermodynamics of a Tire Pump,
(Nov 29, 2007).
.ps version.
Radiation from Hertzian Dipoles in a Uniaxial
Anisotropic Medium,
(Nov 16, 2007).
.ps version.
Relativity of Steady Energy Flow,
(Nov 3, 2007).
.ps version.
"Hidden" Momentum in a Sound Wave?,
(Oct 31, 2007).
.ps version.
Energy Flow in a Moving Bimetallic Strip,
(Oct 28, 2007).
.ps version.
Energy, Momentum and Stress in a Belt Drive,
(Oct 20, 2007).
.ps version.
Tokyo Drift,
(Oct 7, 2007).
.ps version.
Currents in a CenterFed Linear Dipole Antenna,
(June 27, 2007).
.ps version.
Voltage Across the Terminals of a Receiving Antenna,
(June 25, 2007).
.ps version.
Electric Guitar Pickups,
(May 6, 2007). .ps version.
Torque Analyses of a Sliding Ladder,
(May 6, 2007). .ps version.
Flow of Energy and Momentum in a the Near Zone
of a Hertizan Dipole,
(Apr 11, 2007).
.ps version.
Flow of Energy and Momentum in a Coaxial Cable,
(Mar 31, 2007).
.ps version.
Space Charge in Ionization Detectors,
with S. Palestini (Mar 25, 2007).
.ps version.
Path Length of Muons Traversing an Arbitrary Volume,
with H. Jostlein (Mar 24, 2007).
.ps version.
The Fields of a Pulsed, Small Dipole Antenna,
(Mar 16, 2007).
.ps version.
Where Does the Power Become AC in an AC Power Source?
(Feb 27, 2007).
.ps version.
Permeable Shell in a Uniform External Field,
(Feb 24, 2007).
.ps version.
Stabilization of Insect Flight
via Sensors of Coriolis Force,
(Feb 17, 2007).
.ps version.
Galilean Transformation of Wave Velocity,
with J.L. Junquera
(Jan 14, 2007). .ps version.
Hexagonal Pencil Rolling on an Inclined Plane
(Nov 14, 2006).
.ps version.
Regular and Chaotic
Dynamics, v 13, p 332 (2008).
Path of Minimum Radiation,
Bruce Winstein (U. Chicago, Oct 2, 2006).
The Fields of a Short, Linear Dipole Antenna
If There Were No Displacement Current
(July 5, 2006).
.ps version.
"CrossedField" and "EH" Antennas
Including Radiation from the Feed Lines
and Reflection from the Earth's Surface
(July 4, 2006).
.ps version.
Slepian's Electromagnetic Spaceship
(June 18, 2006).
[Still a factor of 2 loose near eq. (7).]
.ps version.
Electromagnetic Momentum of a Capacitor
in a Uniform Magnetic Field
(June 18, 2006).
.ps version.
Cullwick's Paradox: Charged Particle on the Axis
of a Toroidal Magnet
(June 4, 2006).
.ps version.
Russian translation by V. Onoochin of an early version.
Momentum in a DC Circuit
(May 26, 2006).
.ps version.
McKenna's Paradox: Charged Particle Exiting the
Side of a Solenoid Magnet
(Apr 12, 2006).
.ps version.
Four Expressions for Electromagnetic Field
Momentum
(Apr 10, 2006).
.ps version.
Reflections of a (Skeptical) Experimental HighEnergy
Physicist after Teaching a Course on Quantum Computation
(Feb 24, 2006).
Currents in a Conducting Sheet with a Hole
(Feb 22, 2006).
.ps version.
Some Properties of Sourceless Wave Packets
(Feb 10, 2006).
.ps version.
The Radiation Reaction Force and the Radiation
Resistance of Small Antennas
(Jan 21, 2006). .ps version.
Onoochin's Paradox
(Jan 1, 2006).
.ps version.
Russian translation by V. Onoochin (Sep 2008).
Can a "HiddenVariable" Quantum Theory Evade the
"NoCloning" Theorem?
(Oct 6, 2005).
.ps version.
Impedance Matching of Transmission Lines
(July 20, 2005).
.ps version.
DensityMatrix Description of the EPR
"Paradox" (Mar 31, 2005).
.ps version.
Accuracy of Measurements of a CPViolating
Asymmetry (Mar 25, 2005).
.ps version.
Classical Lifetime of a Bohr Atom, with J.D. Olsen
(Mar 7, 2005).
.ps version.
Vena Contracta
(Feb 16, 2005).
.ps version.
Letter to the Editor (Feb. 2, 2005)
regarding
Einstein's boxes, by T. Norsen,
Am. J. Phys. 73, 164 (2005).
Radiation from an AC Voltage Source
(Jan 9, 2005).
.ps version.
Can an Antenna Be Cut Into Pieces (Without Affecting
Its Radiation)?, with D.J. Jefferies
(Nov 10, 2004).
.ps version.
A 10frame animation of the near electric field
of a 3 λ / 2 dipole antenna.
Successful Quantum Cloning Would Imply FasterThanLight Communication
(Oct 10, 2004).
.ps version.
Quantum Measurement Requires Entanglement; Measurement Takes Time
(Oct 7, 2004).
.ps version.
Maxwell's Demon
(Oct 3, 2004).
.ps version.
Scattering of a Plane Wave by a Small
Conducting Sphere,
(July 13, 2004).
.ps version.
Radiation in the Near Zone of a CenterFed
Linear Antenna,
(June 21, 2004).
.ps version.
Radiation in the Near Zone of a Short, CenterFed
Biconical Antenna,
(June 14, 2004).
.ps version.
Radiation in the Near Zone of a Small Loop Antenna,
(June 7, 2004), with an Appendix on Hertz vectors.
.ps version.
A Paradox Concerning the Energy of a Dipole
in a Uniform External Field, with J. Castro
(May 3, 2004). .ps version.
Radiation in the Near Zone of a Hertzian Dipole,
(Apr 22, 2004). .ps version.
How to Fry an IGCT in 1 μs or Less,
(Apr 17, 2004).
.ps version.
Radial Dependence of Radiation from a Bounded Source,
(Jan 25, 2004).
.ps version.
SynchrotronĈerenkov Radiation,
Letters to Science, vol. 303, p. 310 (2004).
Money Spinner or Loopy Idea,
Edwin Cartlidge, Science, 301, 1463 (2003).
Small Fractal Antennas,
(Dec 22, 2003).
.ps version.
A Neutrino Horn Based on a Solenoid Lens,
(Dec 1, 2003). .ps version.
Magnetic Field in a TimeDependent Capacitor,
(Oct 30, 2003).
.ps version.
Bunching of Photons When Two Beams Pass Through a
Beam Splitter, with L.J. Wang
(Aug 17, 2003).
.ps version.
Hertzian Dipole Radiation via the
WeizsäckerWilliams Method, with M.S. Zolotorev
(Aug 4, 2003).
.ps version.
Using Conformal Maps to Explore the Potential
of Wire Grids, by T. Dimofte (July 28, 2003).
.ps version.
A Parallelogram Loop Antenna,
(May 28, 2003). .ps version.
Isotropic Radiators, with Haim Matzner
(Apr. 8, 2003). .ps version.
The Barnett Experiment with a Rotating Solenoid
Magnet, (Apr. 6, 2003). .ps version.
Electromagnetic Fields of a Rotating Shell
of Charge,
(Apr. 3, 2003). .ps version.
Dielectric Cylinder That Rotates in a Uniform
Magnetic Field
(Mar. 12, 2003).
.ps version.
Notes on Electrostatic Wire Grids,
(Mar. 5, 2003). .ps version.
A Magnetic Linear Accelerator,
(Mar. 3, 2003). .ps version.
Capacitance of a Thin Conducting Disk and of
Conducting Spheroids,
(Feb. 25, 2003). .ps version.
Volume and Surface Area of a Sphere in N Dimensions,
(Feb. 4, 2003). .ps version.
Gaussian Laser Beams via Oblate Spheroidal
Waves, (Oct. 19, 2002).
The Electric Potential of Particle Detectors with
Rectangular CrossSection, with C. Lu (Oct. 9, 2002).
.ps version.
Conducting Ellipsoid and Circular Disk,
(Sept. 21, 2002). .ps version.
Conducting Spherical Shell with a Circular
Orifice,
(Sept. 21, 2002). .ps version.
Two Conducting Spheres at the Same Potential,
(Sept. 19, 2002). .ps version.
Magnetostatic Spin Waves, (Sept. 15, 2002).
.ps version.
An Electrostatic Wave, (July 28, 2002).
.ps version.
A Capacitor Paradox, (July 10, 2002).
.ps version.
Fluid Flow Velocity at a Wall, Alex McDonald
(June 24, 2002).
.ps version.
Green's Function for a Conducting Plane with a
Hemispherical Boss (Apr. 23, 2002).
.ps version.
Electromagnetic Field Energy
(Apr. 3, 2002).
.ps version.
"Hidden" Momentum in a Coaxial Cable
(Mar. 28, 2002).
.ps version.
Methods of Calculating Forces on Rigid, Linear
Magnetic Media
(Mar. 18, 2002).
Magnetic Force on a Permeable Wire
(Mar. 17, 2002).
.ps version.
Conducting Sphere That Rotates in a Uniform
Magnetic Field
(Mar. 13, 2002).
.ps version.
Maximal Gravity at the Surface of an
Asteroid
(Feb. 18, 2002).
.ps version.
Accessing Phases of CKM Matrix Elements Via the Decay
B^{0}_{d} → π^{+}π^{},
with Chris Tully
(Dec. 18, 2001).
.ps version.
Maximum Energy of Circular Colliders,
with Chris Tully
(Dec. 10, 2001).
.ps version.
Why Doesn't a Steady Current Radiate?
(Dec. 1, 2001).
.ps version.
A Slingshot Orbit
(Nov. 18, 2001).
.ps version.
Diamagnetic Levitation, with Bob Austin
(Nov. 15, 2001).
.ps version,
.mpg movie of a flying frog.
Floating gold in cryogenic oxygen.
An OffAxis Neutrino Beam
(Nov. 6, 2001). .ps version.
3 x 3 Magic Squares with Duplicate Digits Allowed,
with Nancy Schaefer (Oct 13, 2001).
.ps version.
Leaky Capacitors,
with T.J. Maloney
(Oct 17, 2001). .ps version.
Vertical Oscillations of a Hanging Cable
(Oct 7, 2001). .ps version.
A Conducting Checkerboard
(Oct 4, 2001). .ps version.
Dipole in Shell
(Oct 2, 2001). .ps version.
Small Oscillations of a Suspended Hoop,
with Alex McDonald (Oct 1, 2001). .ps version.
Uncertainties in the Measurement of the Momentum
and Position of an Electron
(Sept 20, 2001). .ps version.
Self Trapping of Optical Beams
(Apr 15, 2001). .ps version.
The Rolling Motion of a Disk on a Horizontal
Plane, with Alex McDonald (Mar 28, 2001).
.ps version.
To Construct a Square with Edges on Any Four Points,
with Owen Schaefer (Feb 11, 2001).
.ps version.
Comments on Energy Flow in a NegativeGroupVelocity Wave
(Feb 4, 2001).
.ps version.
A Josephson Junction
(Dec 5, 2000).
.ps version.
A Flapping Toy
(Nov 30, 2000).
.ps version.
Some Mechanics of Toys (Nov 29, 2000).
.ps version.
The Maximum Energy Attainable in a Betatron
(Nov 19, 2000).
.ps version.
Electron Bubbles in Liquid Helium
(Nov 12, 2000). .ps version. See also,
Nevis Summer
Workshop on Electron Bubble Particle Detectors.
Motion on a Torus
(Oct 21, 2000).
.ps version.
Transmission of Microwaves through
SubMillimeter Slit Arrays,
V. Pelletier (Oct 18, 2000).
Free Precession
(Aug 10, 2000).
.ps version.
Negative Group Velocity
(July 23, 2000).
Am. J. Phys. 69, 607 (2001).
.ps version.
Radial Viscous Flow between Two Parallel Annular
Plates (June 23, 2000).
.ps version.
Bessel Beams (June 17, 2000).
.ps version.
Maximum Height of Mud Thrown from a Wheel,
Alex McDonald (May 28, 2000).
.ps version.
Euler's disk and its finite time singularity,
by H.K. Moffatt, Nature 404, 833 (Apr 20, 2000).
A comment by A. Ruina (June 2000).
Further comments,
Nature 408, 540 (Nov 30, 2000).
Polarization Dependence of Emissivity,
with D. Strozzi (Apr 3, 2000).
.ps version.
Resistance of a Disk
(Mar 31, 2000).
.ps version.
Gaussian Laser Beams with Radial Polarization (Mar 14, 2000),
.ps version.
.pdf version with highres figures.
Transparencies with highres figures.
Complex Functions and Electrostatics,
(Feb 28, 2000).
.ps version.
An OffCenter "Coaxial" Cable,
(Nov 21, 1999).
.ps version.
A Phased Antenna Array,
by Dan Marlow (Nov 11, 1999).
.ps version.
Long Rod with Uniform Magnetization
Transverse to its Axis,
(Nov 3, 1999).
.ps version.
TimeReversed Diffraction,
with Max Zolotorev (Sep 5, 1999). Updated Sep 1, 2009 with an Appendix on
Vector Diffraction Formalism.
.ps version.
Classical Radiation Processes
in the WeizsäckerWilliams Approximation, with Max Zolotorev
(Aug 25, 1999).
.ps version.
A Bounded Source Can't Emit a Unipolar Electromagnetic
Pulse, with KwangJe Kim, Gennady Stupakov and Max Zolotorev (May 1, 1999).
.ps version.
Penrose Decoherence
(Apr 28, 1999).
.ps version.
Slow Light (Apr 3, 1999);
Am. J. Phys. 68, 293 (2000).
.ps version.
Draft: Measurement of Pulsewidth via
Correlations in Intensity Fluctuations, with Max Zolotorev
(Mar 23, 1999).
.ps version.
If a Pig Had Wings...,
(Feb 11, 1999).
.ps version.
Diffraction as a Consequence of Faraday's Law,
with Max Zolotorev (Jan 11, 1999);
Am. J. Phys. 68, 674 (2000).
.ps version.
Images of Electric and Magnetic Dipole Antennas
in a Conducting Plane (Dec 5, 1998).
.ps version.
A Mechanical Model that Exhibits a Gravitational
Critical Radius (Dec 2, 1998).
Am. J. Phys. 69, 617 (2001).
.ps version.
Magnetars (Nov 29, 1998);
Am. J. Phys. 68, 775 (2000).
.ps version.
The Transverse Momentum of an Electron in a Wave
(Nov 15, 1998). .ps version.
Nobel Sonoluminescence
(Nov 14, 1998);
Popular Science, Feb. 1999, p. 8.
.ps version.
Laser Tweezers (Nov 13, 1998),
Am. J. Phys. 68, 486 (2000).
.ps version.
Canonical Angular Momentum of a Solenoid Field
(Nov 13, 1998). .ps version.
The Charge Distribution on the Cathode of a Straw Tube
Chamber, with C. Lu (Oct 1, 1998).
.ps version.
Survivability of a Target for an Intense Proton Beam,
(Apr 17, 1998). .ps version.
The Fields in a Box with Resistive Walls,
(Apr 16, 1998). .ps version.
The Rare Decay K_L > pi0 nu nubar, with Dan Marlow
(Apr 16, 1998).
.ps version.
Classical "Dressing" of a Free Electron in a
Plane Electromagnetic Wave, with K. Shmakov (Feb 28, 1998).
.ps version.
A Maxwellian Perspective on Particle
Acceleration,
with Max Zolotorev (Feb 24, 1998),
.ps version.
HawkingUnruh Radiation
and Radiation of a Uniformly Accelerated Charge (Feb 3, 1998)
.ps version.
Quantum Aspects of Beam Physics, p. 626.
Energy Balance in an Electrostatic
Accelerator, with Max Zolotorev (Feb 1, 1998)
.ps version.
The HawkingUnruh Temperature
and Damping in a Linear Focusing Channel (Jan 30, 1998)
.ps version.
Quantum Aspects of Beam Physics, p. 643.
A Relativistic Electron Can't Extract Net
Energy from a `Long' Laser Pulse,
(Aug 22, 1997).
.ps version.
Physics in the Laundromat
(Aug 5, 1997);
Am. J. Phys. 66, 209 (1998).
.ps version.
Limits on the Applicability of Classical
Electromagnetic Fields as Inferred from the Radiation Reaction,
(May 12, 1997).
.ps version.
Temporary Acceleration of Electrons While
Inside an Intense Electromagnetic Pulse,
with K. Shmakov, (Nov. 20, 1997).
Phys. Rev. STAB 2, 121301 (1999).
.ps version.
The Levitron (Apr 4, 1997).
.ps version.
The Greek Eccentricity
(Mar 14, 1997). .ps version.
The Fractal Dimension of a Ball of Aluminum Foil
(Mar 6, 1997). .ps version.
The Flyball Governor, by Dan Marlow
(Mar 5, 1997).
.ps version.
The WeizsäckerWilliams Approximation to Trident
Production in ElectronPhoton Collisions, with C. Bula
(Feb 28, 1997).
.ps version.
The Radiofrequency Quadrupole (Feb 27, 1997).
.ps version.
Notes on Synchrotron Radiation
(Feb 11, 1997).
.ps version.
Pitching Pennies into a Magnet
(Jan 15, 1997).
.ps version.
The Fields Outside a Solenoid with a TimeDependent
Current (Dec 6, 1996);
Am. J. Phys. 65, 1176 (1997).
.ps version.
The Relation between Expressions for TimeDependent
Electromagnetic Fields given by Jefimenko and by Panofsky and Phillips
(Dec 5, 1996);
Am. J. Phys. 65, 1074 (1997).
.ps version.
Vector Gravity
(Dec 4, 1996);
Am. J. Phys. 65, 591 (1997).
.ps version.
Group Velocity (Dec 4, 1996);
Am. J. Phys. 66, 656 (1998).
.ps version.
The Electromagnetic Fields Outside a Wire That Carries
a Linearly Rising Current (Nov 28, 1996).
.ps version.
The Rolling Motion of a HalfFull Beer Can
(Nov 14, 1996).
.ps version.
Distortionless Transmission Line
(Nov 11, 1996).
.ps version.
Positron Production in a Plasma Wakefield
Accelerator, (Oct. 29, 1996),
.ps version.
Hyperdeuterons (Apr 22, 1996).
.ps version.
Noncontact Measurement of the Tension of a Wire,
with Mark Convery (Apr 14, 1996).
.ps version.
Motion of a Point Charge Near an Electric Dipole
(Mar 19, 1996).
.ps version.
Can an Electron Be at Rest?
(Aug 30, 1995);
Am. J. Phys. 64, 1098 (1996).
.ps version.
Electromagnetic Field Momentum
(Aug 30, 1995);
Am. J. Phys. 64, 15 (1996).
.ps version.
Gaussian Laser Beams and Particle
Acceleration,
(May 26, 1995),
.ps version.
Accelerating Fluids
(May 4, 1995);
Science 268, 1261 (1995).
.ps version.
SingleBubble Sonoluminescence,
(Feb 2, 1995).
.ps version.
Levitating Beachballs (Dec 6, 1994);
Am. J. Phys. 68, 388 (2000).
.ps version.
The Geostrophic Wind, by Will Happer
(Dec 9, 1993).
.ps version.
Circular Orbits Inside the Sphere of Death
(Nov 8, 1993);
Am. J. Phys. 66, 419 (1998).
.ps version.
Video clips of Bela Tabak's Thunderdome.
Six Ways to Measure CPViolating Phases
in B Decays (Sep 20, 1992).
.ps version.
MaximumLikelihood Analysis of CPViolating
Asymmetries (Sep 4, 1992).
.ps version.
A Primer on CP Violation in the BMeson System
(May 25, 1990).
.ps version.
Motion of a Leaky Tank Car
(Dec 4, 1989);
Am. J. Phys. 59, 813 (1990).
.ps version.
Right and Wrong Use of the Lenz Vector for NonNewtonian
Potentials, with C. Farina and A. Tort
(May 23, 1989);
Am. J. Phys. 58, 540 (1990).
.ps version.
The Tennis Racquet Theorem
(Dec 1, 1988).
.ps version.
An RF Cavity in Which Transverse Fields Grow Linearly with
Radius
(Mar 24, 1988).
.ps version.
The HawkingUnruh Temperature and Quantum Fluctuations in Particle
Accelerators, (72kB, Mar. 9, 1987). Proc. PAC1987,
p. 1196.
.ps version.
Radiation from a Superluminal Source
(Nov 26, 1986);
Am. J. Phys. 65, 1076 (1997).
.ps version.
The Helical Wiggler, with H. Mitter,
(Oct 12, 1986).
.ps version.
The LaserDriven Vacuum Photodiode (Sep 26, 1986).
.ps version.
Fundamental Physics During Violent Accelerations, (Jan. 7,
1985),
Laser Acceleration of Particles, C. Joshi and T. Katsouleas, eds.,
AIP Conf. Proc. 130, 23 (1985).
The Grating Accelerator
(Sep 14, 1984).
.ps version.
Stress and Momentum in a Capacitor That Moves with
Constant Velocity
(Apr 21, 1984).
.ps version.
A Naive Estimate of the Coupling Constant in Yukawa Theory
(Apr 17, 1984).
.ps version.
Cerenkov Radiation by a Neutron and by an Electric Dipole
(Apr 15, 1984).
.ps version.
Feynman Cylinder Paradox, with John Belcher
(1983).
.ps version.
The Guard Ring of a Streamer Chamber
(Oct 1, 1983).
.ps version.
The Amp Clamp
(Apr 19, 1983).
.ps version.
SpinOrbit Coupling in the EarthMoon System
(Nov 2, 1982).
.ps version.
Transparencies from a colloquium:
Does Quantum Mechanics Require
Superluminal Connections?
(Dec 3, 1981). The answer is NO!
Transverse Waves on an Inelastic Rotating
String
(Dec 1, 1980). .ps version.
Transverse Waves on an Inelastic Vertical
String
(Nov 30, 1980). .ps version.
Off the Rim
(Nov 25, 1980). .ps version.
The Golfer's Nemesis
(Nov 23, 1980). .ps version.
Spinning Basketballs
(Nov 21, 1980). .ps version.
GreekTemple Seisomograph
(Sep 1, 1980). .ps version.
The Shape of Tokamak Coils
(May 17, 1980). .ps version.
Ĉerenkov Radiation in a Dielectric
Wave Guide
(Sep 30, 1979). .ps version.
SelfInduced Transparency
(May 3, 1979).
.ps version.
Wave Amplification in a Magnetic Medium
(May 1, 1979).
.ps version.
The Force on an Antenna Array
(May 1, 1979).
.ps version.
RadiatedPower Distribution in the Far Zone of a Moving
System
(Apr 24, 1979).
.ps version.
Electromagnetism and Newton's 3^{rd} Law
(Apr 20, 1979).
.ps version.
Electron Trajectories in a Vacuum Coaxial Cable
(April 17, 1979). Comment about Lorentz force accelerators (MPD's) added
Feb. 2008.
.ps version.
Gauging Away Polarization States of Waves
(Apr 14, 1979).
.ps version.
LienardWiechert Potentials and Fields
via Lorentz Transformations
(Apr 7, 1979).
.ps version.
Electric Potential of a Resistive Bead
(Mar 1, 1979).
.ps version.
BeamSplitter Paradox,
with Bruce Winstein
(Dec 1, 1978).
NeutralPion Decay
(Sep 15, 1976). .ps version.
Properties of the MaximumLikelihood
Method
(Aug 5, 1971), CALT68321.
Polarization Precession
(Jan 14, 1970). .ps version.
CALT68236.
FloatingWire Simulation of the Trajectory of a
Charged Particle in a Magnetic Field
(Sep 1, 1969).
.ps version.
A Solution to the Problem
of Apollonius
(May 19, 1964).
Extension into Three Dimensions of the
Classical Problem of Apollonius
(1963).
Ph101 Laboratory Manual, Fall 1996:
Introduction to Ph101 Laboratory.
Lab 1, Precision Estimates.
Lab 2, Newton's First and Second
Laws for Linear Motion.
Lab 3, Motion in Two Dimensions.
Lab 4, The Behavior of a Simple
Pendulum and a Precision Measurement of g.
Lab 5, The Physics of Rotating
Bodies.
Lab 6, The Physics of Springs.
Lab 7, Physics in Collision.
Lab 8, Friction in Fluids.
Ph101 2008
Learning Guide, Fall
2008.
Ph101 2009
Laboratory Manual Fall
2009.
Ph101 2012
Laboratory Manual Fall
2012.
Ph101 2013
Laboratory Manual Fall
2013.
Ph101 2014
Laboratory Manual Fall
2014.
Ph103
2009 Ph103 Laboratory
Manual.
2010 Ph103/105 Laboratory Manuals:
Entire Manual.
Introduction.
Lab 1: Motion in Two Dimensions.
Lab 2: Forces in Fluids.
Lab 3: Collisions in Two Dimensions.
Lab 4: Rolling Friction.
Lab 5: Rotational Motion.
Lab 6: A Precision Measurement of g.
.xls sheet for Lab 6.
Lab 7: Coupled Pendula and Normal Modes.
.xls sheet for Lab 7.
Lab 8: The Speed of Sound and Specific Heats
of Gases.
Lab Manual Appendices.
Ph103 Laboratory
Troubleshooting Manual
(mainly for AI's).
Ph104 Laboratory Manuals.
Spring 2004.
Ph104 Laboratory Manual
Introduction.
Lab 1, Exploring Electrostatics
with an Electroscope.
Lab 2, More Studies with an
Electroscope.
Lab 3, Resistors, Capacitors,
DC Circuits, and RC Circuits.
Lab 4, e/m of the Electron,
Measurement of μ_{0}.
Lab 5, Make and Test a Motor.
Lab 6, Oscilloscope, Signal Generator
and Filters.
Lab 7, RLC Circuits.
Lab 8, Geometrical Optics, Optical
Instruments.
Lab 9, Physical Optics: Interference
and Diffraction.
Lab 10, Diode Rectifier and
Transistor AC Amplifier.
Lab 11, AM Radio.
Instructions for
Laboratory Instructors.
Ph205, Mechanics.
Lecture 1, Review of the Principles of
Elementary Mechanics.
Maximum Height of Mud Thrown From a Wheel.
The Pin and the Pendulum.
Slingshot Ride.
A Gentler LooptheLoop.
Small Oscillations of a Mass That Slides inside
a Cylinder Which Rotates about a Horizontal Axis.
Skiing on a Cosine Hill.
Nahin's Bobsled.
Lecture 2, Mechanics of a System of Particles.
Why Doesn't a Picture Hang Straight?
If a Pig Had Wings...
Air Hockey Bowling.
Box Toss.
Energy Conservation in a Pulley + Mass System.
Can Salmon Swim up a Waterfall after Leaping into It?
Rain and Relativity.
Rocket Car.
Canoe ± Rock.
Rayliegh's Spinning Ring.
Ladder + Rope.
Tokyo Drift.
Hexagonal Pencil Rolling on an Inclined Plane.
Motion of a Cylinder Tied to a Slope by a String.
Greek Temple Seismograph.
Relativity of Steady Energy Flow.
Energy Flow in a Moving Bimetallic Strip.
Energy, Momentum and Stress in a Belt Drive.
Center of Mass of a Relativistic Rolling Hoop.
"Hidden" momentum, according to the definition that I favor, cannot exist in an "allmechanical" system. Here are some examples in which one might say that something is "hidden", but this is not "hidden momentum":
"Hidden" Momentum in a River.
"Hidden" Momentum in a Set of Circulating Rockets.
"Hidden" Momentum in an Unbalanced Tire.
"Hidden" Momentum in an Oscillating Spring.
"Hidden" Momentum in an Oscillating Tube of Water.
"Hidden" Momentum in a Link of a Moving Chain.
"Hidden" Momentum in a Leaping Beaded Chain.
"Hidden" Momentum in Sound Wave.
"Hidden" Momentum in a Spinning Sphere.
"Hidden" Momentum in a Linked Pair of Gyrostats.
"Hidden" Momentum in a Compressed Rod?
"Hidden" Momentum in an Isolated Brick?
Force and Torque while Frying an Egg
"Hidden" momentum in electromechanical systems is discussed in the examples following Lecture 24 of Ph206/501, Electrodynamics.
Lecture 3, Development of a General Method,
Lagrange's Equations.
Lecture 4, Examples of Lagrange's Method.
The Flyball Governor.
Spinning Lasso.
Lecture 5, Calculus of Variations.
Maximal Gravity at the Surface of an Asteroid.
Lecture 6, More About Lagrange's Equations.
Breakdown of a Misinterpretation of Noether's Theorem.
Lecture 7, Impulses.
Lecture 8, Small Oscillations About
Equilibrium.
A SlidingBlock Problem.
Small Oscillations of a Suspended Hoop.
A Flapping Toy.
Motion on a Torus.
A Mechanical Model
That Exhibits a Gravitational Critical Radius.
Relativistic Harmonic Oscillator.
Lecture 9, Central Forces.
The Greek Eccentricity.
Lecture 10, Central Forces, II.
Pendulum in Orbit.
Dumbell in Orbit.
Does the Moon Always Fall Towards the Sun?
A Slingshot Orbit.
Right and Wrong Use of the Lenz Vector
for NonNewtonian Potentials.
Laplace and the Speed of Gravity.
Lecture 11, Mechanical Similarity, Virial
Theorem, Collisions.
Lecture 12, Scattering.
Lecture 13, More About Oscillations.
Accelerating Through a Resonance on a "Washboard" Road.
Lecture 14, Coupled Oscillations.
SpinOrbit Coupling in the EarthMoon System.
Lecture 15, Nonlinear Oscillations.
Lecture 16, Accelerated Coordinate Systems.
Accelerating Fluids.
Science 268, 1261 (1995).
The Geostrophic Wind.
An IllPosed Problem in RigidBody Dynamics.
Lecture 17, Motion of a Rigid Body.
Physics in the Laundromat.
Stabilization of Insect Flight
via Sensors of Coriolis Force.
Lecture 18, Motion of a Rigid Body with No
External Torques.
Free Precession.
Lecture 19, Motion of a Spinning Top
Including Gravity.
Lecture 20, Rolling without Slipping,
Hamiltonian Methods.
Comments on Torque Analyses.
Torque Analyses of a Sliding Ladder.
Rolling Off a Log with Friction.
The Rolling Motion of a HalfFull Beer Can.
The Rolling Motion of a Disk on a Horizontal Plane.
Circular Orbits inside the Globe of Death.
Cylinder Rolling on Another Rolling Cylinder.
Cylinder Rolling inside Another Rolling Cylinder.
Slab Rolling on a Rolling Cylinder.
A Rolling Cylinder Problem.
A Damped Oscillator as a Hamiltonian System.
Lecture 21, Wave Motion.
Vertical Oscillations of a Hanging Cable.
Group Velocity.
Galilean Transformation of Wave Velocity.
Lecture 22, Standing Waves.
Transverse Waves on an Inelastic Rotating String.
Transverse Waves on an Inelastic Vertical String.
Lecture 23, Traveling Waves.
Lecture 24, Water Waves.
Other Fluid Problems:
Bernoulli's Equation for a Rotating Fluid.
Is Bernoulli's Equation Relativistically Invariant?
Vena Contracta.
Levitating Beachballs.
SingleBubble Sonoluminescence.
Nobel Sonoluminescence;
Popular Science, Feb. 1999, p. 8.
Fluid Flow Velocity at a Wall.
Oscillating Fluid in a UTube.
Hydraulic Brake.
Leaky Syringe.
Pressure in Fluid Flow Past a Sphere.
Rotating Water Bucket with Lid.
Leaky Bucket Suspended by a Spring.
Torricelli's Law for Large Holes.
Radial Viscous Flow
between Two Parallel Annular Plates.
Lecture 26, Solitons.
Addenda: VariableMass Problems:
Wagon in the Rain.
Motion of a Leaky Tank Car.
Rolling Water Pipe.
YoYo Variants.
A Falling, Folded String.
Buquoy's Problem: Lifting a String from a Table.
Uncoiling on a Horizontal Surface.
Snowball/Log Rolling down a Snowy Slope.
Force and Torque while Frying an Egg.
Addenda: Statistical Mechanics Problems:
From Fick's Law to the Mean Free Path.
Heat Flow from a Point Source at the End of a Bar.
Thermodynamics of a Tire Pump.
Entropy Generation in the Merging of Two Ideal Gases.
Maxwell's Demon.
Information Channel Capacity.
Problem Set 1.
Handwritten version,
Solutions.
Problem Set 2.
Handwritten version,
Solutions.
Problem Set 3.
Handwritten version,
Solutions.
Problem Set 4.
Handwritten version,
Solutions.
Problem Set 5.
Handwritten version,
Solutions.
Problem Set 6.
Handwritten version,
Solutions.
Problem Set 7.
Handwritten version,
Solutions.
Problem Set 8.
Handwritten version,
Solutions.
Problem Set 9.
Handwritten version,
Solutions.
Problem Set 10.
Handwritten version,
Solutions.
Problem Set 11.
Handwritten version,
Solutions.
Problem Set 12.
Handwritten version,
Solutions.
Final Exam, 1981.
Final Exam, 1983.
Final Exam, 1989,
Solution.
Final Exam, 1990,
Solution.
Ph304, Electrodynamics, Problem
Sets. MKSA units are employed.
Set 1, .ps version.
Set 2, .ps version.
Set 3, .ps version.
Set 4, .ps version.
Set 5, .ps version.
Set 6, .ps version.
Set 7, .ps version.
Set 8, .ps version.
Set 9, .ps version.
Set 10, .ps version.
Set 11, .ps version.
Set 12, .ps version.
Midterm exam, 2002,
.ps version.
Midterm exam, 2003,
.ps version.
Final exam, 2002,
.ps version.
Final exam, 2003,
.ps version.
Ph406, Elementary
Particle Physics.
Lecture notes from Ph529.
2014 Problem Sets:
Set 1.
Solutions.
Set 2.
Solutions.
Set 3.
Solutions.
Set 4.
Solutions.
Set 5.
Solutions.
Set 6.
Solutions.
Set 7.
Solutions.
Set 8.
Solutions.
Set 9.
Solutions.
Set 10.
Solutions.
Set 11.
Solutions.
Set 12.
Solutions.
Old problem sets, including some nuclear physics:
Set 1 (Feb 1993).
Set 2 (Feb 1993).
Set 3 (Feb 1993).
Set 4 (March 1992).
Set 5 (March 1993).
Set 6 (March 1993).
Set 7 (April 1993).
Set 8 (April 1992).
Set 8 (April 1993).
Set 9 (April 1993, overlaps with set 8 of
1992).
Set 10 (May 1993).
Final Exam (May 1992).
Solutions.
Ph410, Physics of Quantum Computation.
Text/reference for the course is M.A. Nielsen and I.L. Chuang, Quantum Computation and Quantum Information (Cambridge U.P., 2000).
A compendium of research papers relevant to the course.
Ph410 Problems (with solutions. These extensive
24 problems constituted the course.)
Reflections of a (Skeptical) Experimental HighEnergy
Physicist after Teaching a Course on Quantum Computation
(Feb 24, 2006).
Ph206/501, Electrodynamics, Lectures and Problem Sets.
In my opinion, the Graduate Preliminary Exam should cover the material of Lectures 116 (problem sets 18), while that of lectures 1726 (sets 912) goes beyond the core minimum. Gaussian units are employed.
Lecture 1, Overview of
Maxwell's Equations; Electrostatics.
Additional examples:
Motion of a Point Charge near an Electric Dipole.
On the Nature of the Molecular Forces
which regulate the Constitution of the Luminferous Ether, S. Earnshaw,
Trans. Camb. Phil. Soc. 7, 97 (1839).
Lecture 2, Conductors and
Dielectrics.
Additional examples:
Fields inside a Sphere and Shell of Uniform
Polarization.
Does Space Charge or the Dielectric Constant
Affect Induced Charge in a Liquid Argon Detector?
Lecture 3, Electrostatic
Energy, Maxwell Stress Tensor.
Additional examples:
Capacitance of a Thin Conducting Disk
and of Conducting Spheroids.
Power in a Variable Capacitor.
A Paradox Concerning the Energy of A Dipole
in a Uniform External Field.
Energy Balance in an Electrostatic
Accelerator.
Field Energy of Two Spheres in Contact.
Lecture 4, Potential Theory:
Image Methods, 2D Problems with Rectangular Boundaries.
Additional examples:
Dipole in Shell.
Green's Function for a Conducting Plane with a
Hemispherical Boss.
Two Conducting Spheres at the Same Potential.
Dielectric (and Magnetic) Image Methods.
Image Method for an Electric Charge above a
Topological Insulator with a Quantum Hall Surface.
Notes on Electrostatic Wire Grids.
The Electric Potential of Particle Detectors
with Rectangular CrossSection.
The Charge Distribution on the Cathode
of a Straw Tube Chamber.
The Fields in a Box with Resistive Walls.
Lecture 5, Potential Theory:
2D Problems with Cylindrical and Spherical Boundaries.
Additional examples:
The Guard Ring of a Streamer Chamber.
A Conducting Checkerboard.
Lecture 6, Potential Theory:
3D Problems with Cylindrical Boundaries; Conducting Needles, Spheroids,
Disks; Use of Conjugate Functions.
Additonal examples:
Electric Field of a Uniform Charge Density.
Capacitance of a Thin Conducting Disk and of
Conducting Spheroids.
Spherical Capacitor with Anisotropic
Permeability.
Conducting Ellipsoid and Circular Disk.
Conducting Spherical Shell with a Circular
Orifice.
Complex Functions and Electrostatics.
Using Conformal Maps to Explore the Potential of Wire
Grids.
Charging of an Insulator in a Liquid Argon Detector.
Lecture 7, Steady Currents;
Magnetostatics.
Additional examples:
Does Centrifugal Force Affect Electric Currents?
Electromagnetic Fields inside a Perfect Conductor.
Charge Density in a CurrentCarrying Wire.
Electric Potential of a Resistive Bead.
Resistance of a Disk.
Currents in a Conducting Sheet with a Hole.
Leaky Capacitors.
A Conducting Checkerboard.
Maximum Power from DC Current and Voltage Sources.
The Laser Driven Vacuum Photodiode.
Space Charge in Ionization Detectors.
Electric Field Distribution in a ReverseBiased pn Junction.
An Alternative Magnetic Field Based on Ampère's Force Law.
Floating Wire Simulation of the Trajectory of a
Charged Particle in a Magnetic Field.
The Shape of Tokomak Coils.
The Helical Wiggler.
Expansion of an Axially Symmetric, Static
Magnetic Field in Terms of Its Axial Field.
Static Magnetic Field as Determined by Its Value
on a Surface.
Charged, Conducting, Rotating Sphere.
ForceFree Magnetic Fields
aka Eigenfunctions of the Curl Operator.
TwoDimensional Multipole Magnets.
Weber's Electrodynamics and the Hall Effect.
Graneau's Electromagnetic Submarine.
Lecture 8, Sources of the
Magnetic field; Magnetic Materials.
Additional examples:
Conversions of D and H between SI and Gaussian Units.
BiotSavart vs. EinsteinLaub Force Law.
Permeable Shell in a Uniform External Field.
Electric and Magnetic Hoses.
Magnetic Field in a TimeDependent Capacitor.
Methods of Calculating Forces on Rigid
Magnetic Media.
Magnetic Force on a Permeable Wire.
Forces on Magnetic Dipoles.
Forces on Halves of a Uniformly Magnetized Sphere.
Force between Two Uniformly Magnetized Spheres.
Can an ElectricCurrent Density Be Replaced by an Equivalent
Magnetization Density?.
Mertz' Paramagnetic Fluid Pump.
Lecture 9, Faraday's Law, Maxwell's Equations, Gauge Invariance.
Additional examples:
Is Faraday's Disk Dynamo a FluxRule Exception?
Hering's FluxLinkage Paradox.
Another Circuit Paradox of Hering.
Blondel's Experiment.
The HooperMonstein Paradox.
Marinov's Magnetic Puzzler.
Marinov's Paradoxical Motor,
Electric Guitar Pickups.
The Amp Clamp.
Magnetic Damping.
Pitching Pennies into a Magnet.
Noncontact Measurement of the Tension of a Wire.
Are Christoffel Symbols Needed to Analyze Transient
Phenomena in Faraday's Dynamo?.
Can Magnetic Field Lines Break and Reconnect?
Electrodynamics of Rotating Systems.
Electromagnetic Fields of a Rotating Shell
of Charge.
The WilsonWilson Experiment.
The Barnett Experiment with a Rotating Solenoid
Magnet.
Conducting Sphere
That Rotates in a Uniform Magnetic Field.
Dielectric Cylinder
That Rotates in a Uniform Magnetic Field.
Charged, CounterRotating Disks on a Rotating Platform.
Unipolar Induction
via a Rotating, Conducting, Magnetized Cylinder.
Unipolar Induction via a Rotating Magnetized Sphere.
Magnetic Field at the Origin of a Grounded,
Conducting Sphere Circled by a Moving Charge Q.
Magnetic Field in a TimeDependent Capacitor.
Formal Expressions for the Electromagnetic Potentials
in Any Gauge.
The Helmholtz Decomposition and the Coulomb Gauge.
Helmholtz and the Velocity Gauge.
Helmholtz' Vector Potentials.
Vector Potential of a Long Solenoid in the
Poincaré Gauge.
Poincaré Potential for a Finite Solenoid.
StaticVoltage Gauge.
What Does an AC Voltmeter Measure?
Voltage Drop, Potential Difference and EMF.
Lewin's Circuit Paradox.
Another Circuit Paradox of Hering.
Lecture 10, Electromagnetic
Energy, Momentum and Angular Momentum; Inductance.
Additional examples:
Electromagnetic Field Energy.
Circuit Q and Field Energy.
Does Destructive Interference Destroy Energy?
Field and Kinetic Energies of a Pair of Permanent
Magnetic Dipoles.
A Paradox Concerning the Energy of a Dipole
in a Uniform External Field.
How Much of Magnetic Energy Is Kinetic Energy?
Power Consumption by a Pulsed Copper Magnet.
How to Fry an IGCT in 1 μs or Less.
Comay's Paradox: Do Magnetic Charges Conserve Energy?
Magnetic Forces Can Do Work.
A Magnetic Linear Accelerator.
BallBearing Motor.
On the Transfer of Energy in the
Electromagnetic Field, J.H. Poynting, Phil. Trans. 175, 343 (1884),
Alternative Forms of the Poynting Vector.
729 Variants of Poynting's Theorem.
Poynting's Theorem with Magnetic Monopoles.
Jefimenko's Wedge Circuit.
Where Does the Power Become AC in an AC Power Source?
Energy Flow in a Transformer.
Wireless Power Transmission.
Self Inductance of a Solenoid with a PermanentMagnet
Core.
Stress and Momentum in a Capacitor
That Moves with Constant Velocity.
Fields in a Coaxial Cable with a DC Current.
Flow of Energy and Momentum in a Coaxial Cable.
Momentum of a Charged Particle Orbiting a Magnetic
Dipole.
Electromagnetic Angular Momentum of a Rotating
Cylindrical Shell of Charge.
Canonical Angular Momentum of a Solenoid Field.
A Neutrino Horn Based on a Solenoid Lens.
Birkeland, Darboux and Poincaré: Motion of an
Electric Charge in the Field of a Magnetic Pole.
Electromagnetic Field Angular Momentum of a Charge at Rest
in a Uniform Magnetic Field.
Orbital and Spin Angular Momentum of Electromagnetic Fields.
[See also Lecture 24 for more examples involving field momentum and angular momentum.]
Lecture 11, Introduction to
Electromagnetic Waves.
Additional examples:
Decomposition of Electromagnetic Fields
into Electromagnetic Plane Waves.
A Bounded Source Can't Emit a Unipolar Electromagnetic
Pulse.
The Transverse Momentum of an Electron in a Wave.
Classical "Dressing" of a Free Electron in a
Plane Electromagnetic Wave.
The Radiofrequency Quadrupole.
Galilean Transformation of Wave Velocity.
Potentials for an Electromagnetic Plane Wave.
"Backflow" in the Interference of Two Electromagnetic
Plane Waves.
Lecture 17, Optics and
Diffraction; Gaussian Laser Beams. [I now think that a "short" course on
E&M should include some mention of Gaussian laser beams. Lecture 17 gives
more than a minimal introduction to this topic.]
Additional examples:
BeamSplitter Paradox.
Radiation Pressure
of a Monochromatic Plane Wave on a Flat Mirror.
Diffraction as a Consequence of Faraday's Law.
Gaussian Laser Beams via Oblate Spheroidal
Waves.
Gaussian Laser Beams with Radial Polarization.
.pdf version with highres figures.
Transparencies with highres figures.
Reflection of a Gaussian Optical Beam by a Flat Mirror.
Total and Frustrated Reflection
of a Gaussian Optical Beam.
SecondOrder Paraxial Gaussian Beam.
Bessel Beams.
Exact and geometricaloptics energy trajectories in twisted beams.
TimeReversed Diffraction, with an Appendix on vector diffraction.
Symmetries of Electromagnetic Fields
Associated with a Plane Conducting Screen.
Babinet's Principle for Electromagnetic Fields.
Sommerfeld's Diffraction Problem.
Wire Polarizers.
Polarization Dependence of Emissivity.
Intensity, Brightness and Étendue of an Aperture
Lamp.
A Reflecting Polarizer as a Quantum Watchdog.
Radiative Energy Transfer with Filters and
Stokes/AntiStokes Coatings.
Bunching of Photons
When Two Beams Pass Through a Beam Splitter.
Does Transmission of Light through a Window
Involve Physics at the Planck Scale?
Lecture 12, Plane Waves in
Dielectric Media.
Additional examples:
Group Velocity.
An Electrostatic Wave.
Magnetostatic Spin Waves.
Index of Refraction of a Moving Medium.
Lecture 25, Lasers from a
Classical Perspective.
[Lectures 25 and 26 are extensions of Lecture 12 beyond the core cirriculum.]
Additional examples:
Wave Amplification in a Magnetic Medium.
SelfInduced Transparency.
Self Trapping of Optical Beams.
Lecture 26, Solitons.
Lecture 13, Plane Waves in
Conducting Media.
Additional examples:
Pulses and 1/f Noise.
Distortionless Transmission Line.
Impedance Matching of Transmission Lines.
Waves on a Mismatched Transmission Line.
The Velocity Factor
of an Insulated TwoWire Transmission Line.
LowFrequency Electromagnetic Waves on a
TwistedPair Transmission Line.
An OffCenter "Coaxial" Cable.
Analysis of TEM Waves in a Coaxial Cable
via the Scalar Potential.
Can a Transmission Line Be a Source of Infinite Power?
Lecture 14, Waves in Boxes and
Pipes.
Additional examples:
An RF Cavity in Which Transverse Fields Grow Linearly with
Radius.
Excitation of a Rectangular Electromagnetic
Cavity by a Passing, Relativistic Electron.
Potentials for a Cylindrical Electromagnetic Cavity.
Potentials for a Rectangular Electromagnetic Cavity.
Lorentz Invariance
of the Number of Photons in a Rectangular Cavity.
Slepian's FasterThanLight Wave.
Energy Flow in a Waveguide below Cutoff.
Angular Momentum in Circular Waveguides.
Ĉerenkov Radiation in a Dielectric
Wave Guide.
Transmission of Microwaves through SubMillimeter Slit Arrays.
Lecture 15, Sources of the
Waves  The Retarded Potentials.
Additional examples:
The Relation between Expressions for TimeDependent
Electromagnetic Fields given by Jefimenko and by Panofsky and Phillips.
The Electromagnetic Fields Outside a Wire That Carries
a Linearly Rising Current.
The Fields Outside a Solenoid with a TimeDependent
Current.
The Electric Self Force on a Current Loop.
Maxwell's Objection to Lorenz' Retarded Potentials.
Electric Flux of an Accelerated Charge.
Lecture 16, Multipole
Radiation, Antennas, Scattering.
Additional examples:
FitzGerald's Calculation of the Radiation
of an Oscillating Magnetic Dipole.
The Forces of Electrical
Oscillations Treated According to Maxwell's Theory, H. Hertz,
Nature, 39, 402 (1889).
On the Definition of Radiation by a System of Charges.
The Fields of a Pulsed, Small Dipole Antenna.
Radiation in the Near Zone of a Hertzian Dipole.
Flow of Energy and Momentum
in the Near Zone of a Hertzian Dipole.
Hertzian Dipole Radiation via the
WeizsäckerWilliams Method.
Potentials for a Hertzian Oscillating
Dipole.
Potentials of a Hertzian Dipole in the Gibbs Gauge.
Radiation from Hertzian Dipoles
in a Uniaxial Anisotropic Medium.
Flow of Energy from a Localized Source
in a Uniform Anisotropic Medium.
Radial Dependence of Radiation from a Bounded Source.
Expanding Spherical Shell of Charge.
Why Doesn't a Steady Current Loop Radiate?
Radiation from an AC Voltage Source.
Radiation by a TimeDependent Current Loop.
A Capacitor Paradox.
Charging a Capacitor via a Transient RLC Circuit.
Avril's Radiation Problem.
Classical Lifetime of a Bohr Atom.
The Maximal Energy Attainable in a Betatron.
Maximum Energy of Circular Colliders.
Magnetars.
Path of Minimum Radiation.
Radiation in the Near Zone
of a CenterFed Linear Antenna.
Radiation in the Near Zone
of a Short CenterFed Biconical Antenna.
What is the Role of the Arms of a Linear Broadcast Antenna?
The Fields of a Short, Linear Dipole Antenna
If There Were No Displacement Current.
"CrossedField" and "EH" Antennas Including Radiation from the Feed Lines and Reflection from the Earth's Surface.
Power Received by a Small Antenna.
Voltage Across the Terminals of a Receiving Antenna.
Currents in a CenterFed Linear Dipole Antenna.
A Phased Antenna Array.
Radiation in the Near Zone of a Small Loop Antenna.
A Parallelogram Loop Antenna.
Images of Electric and Magnetic Dipole Antennas
in a Conducting Plane.
Can an Antenna Be Cut Into Pieces (Without Affecting
Its Radiation)?
Small Fractal Antennas.
Isotropic Radiators.
Electromagnetic Fields of a Small Helical Toroidal Antenna.
Reactance of Small Antennas.
Reactance of a Sinusoidally Driven Antenna.
Can Dipole Antennas Above a Ground Plane
Emit Circularly Polarized Radiation?
Radiation of Turnstile Antennas
Above a Conducting Ground Plane.
Orbital and Spin Angular Momentum
of the Fields of a Turnstile Antenna.
Radiation from the Open End of a Coaxial Cable.
An Antenna Reciprocity Theorem.
The BrownTwiss RadioWave Interferometer.
Scattering of a Plane Electromagnetic Wave
by a Small Conducting Sphere.
Scattering of a Plane Electromagnetic Wave
by a Small Conducting Cylinder.
Lecture 18, Special
Relativity. The 4Potential of a Moving Charge.
Additional examples:
Index of Refraction of a Moving Medium.
RadiatedPower Distribution
in the Far Zone of a Moving System.
Maxwell and Special Relativity.
Maxwellian Vacuum Polarization.
Perfectly Conducting Cylinder
in an External, Static Magnetic Field.
Resistive Cylinder
Moving in an External, Static Magnetic Field.
Electrodynamics in 1 and 2 Spatial Dimensions.
A Misuse of Relativity in Circuit Analysis.
The Equivalence Principle and Roundtrip Times for Light.
The Relativity of Acceleration.
The Clock Paradox and Accelerometers.
Time Dilation of Moving Clocks as a Consequence of Length Contraction.
A Misuse of "Maxwell Theory".
Lecture 19, Other Force
Fields. Significance of Gauge Invariance. Fields of a Moving Charge.
Additional examples:
Vector Gravity.
Gravitational Interaction between FastMoving
Particles.
Gauging Away Polarization States of Waves.
Classical Aspects of the AharonovBohm Effect.
LiénardWiechert Potentials and Fields
via Lorentz Transformations.
Displacement Current of a Uniformly Moving Charge.
Force between Two Comoving Electric Charges.
Fields and Moments of a Moving Electric Dipole.
Fields of a Uniformly Accelerated Charge.
Electric Flux of an Accelerated Charge.
Lecture 20, Relativistic
Radiation Effects: Bremsstrahlung. Synchrotron Radiation.
Additional examples:
Notes on Synchrotron Radiation.
Measurement of Pulsewidth via
Correlations in Intensity Fluctuations.
Classical Radiation Processes
in the WeizsäckerWilliams Approximation.
Hertzian Dipole Radiation via the
WeizsäckerWilliams Method.
The WeizsäckerWilliams Approximation to Trident
Production in ElectronPhoton Collisions.
Lecture 21, Relativistic
Radiation Effects: Ĉerenkov Radiation. Transition Radiation.
Additional examples:
Ĉerenkov Radiation in a Dielectric
Wave Guide.
Ĉerenkov Radiation from a Short Path.
Observation of Interference between
Ĉerenkov and Synchrotron Radiation.
SynchrotronĈerenkov Radiation.
Radiation from a Superluminal Source.
Transition Radiation at a MetalVacuum Interface and at the Interface between Two Dielectrics.
Lecture 22, Electromagnetic
Mass. Radiation Reaction.
Additional examples:
On the History of the Radiation Reaction.
Limits on the Applicability of Classical
Electronetic Fields as Inferred from the Radiation Reaction.
The Force on an Antenna Array.
The Radiation Reaction Force and the Radiation
Resistance of Small Antennas.
The Radiation Reaction during the Collapse of a Classical
Electric Dipole.
Radiation Damping of a Refrigerator Magnet.
Lecture 23, Interaction
of Radiation with Matter  Microscopic View.
Additional examples:
Faraday Rotation.
Laser Tweezers.
Slow Light.
Negative Group Velocity.
Doubly Negative Metamaterials.
Can Sheared Surfaces Emit Light?
Lecture 24, Mechanics and
Electromagnetism.
Additional examples:
Electromagnetism and Newton's 3^{rd} Law. Corrects some typos in Lecture 24.
The Field Momentum of Two TimeDependent Dipoles.
Motion of a Pair of Oppositely Charged Spheres.
Motion of a Point Charge near an Electric Dipole.
An Electric Bottle: Charged Particle Orbiting a Charged
Needle.
Magnetic Forces Can Do Work.
A Magnetic Linear Accelerator.
BallBearing Motor.
Does Centrifugal Force Affect Electric Currents?
How Much of Magnetic Energy Is Kinetic Energy?
Canonical Angular Momentum of a Solenoid Field.
A Neutrino Horn Based on a Solenoid Lens.
Birkeland, Darboux and Poincaré: Motion of an
Electric Charge in the Field of a Magnetic Pole.
The Levitron.
Diamagnetic Levitation.
Long Rod with Uniform Magnetization Transverse to its Axis.
Rotational Stability of a Diamagnetic
Rod.
Classical Diamagnetism and the Satellite Paradox.
Backtracking of Charged Particles in a Magnetic Field.
Stability of Transverse Oscillations in a Betatron.
The Maximal Energy Attainable in a Betatron.
Maximum Energy of Circular Colliders.
Electron Trajectories in a Vacuum Coaxial Cable.
Electron Trajectories in a Hall Thruster.
The Grating Accelerator.
The Radiofrequency Quadrupole.
Polarization Precession.
Hamiltonian with z as the Independent Variable.
Emittance Growth from Weak Relativistic Effects.
The Transverse Momentum of an Electron in a Wave.
Classical "Dressing" of a Free Electron in a
Plane Electromagnetic Wave.
Gaussian Laser Beams and Particle Acceleration.
[This was the beginning of my interest in "laser acceleration".]
A Relativistic Electron Can't Extract Net Energy
from a Long Laser Pulse.
A Maxwellian Perspective on Particle Acceleration.
Temporary Acceleration of Electrons
while inside an Intense Electromagnetic Pulse.
HawkingUnruh Radiation and Radiation of
a Uniformly Accelerated Charge.
The HawkingUnruh Temperature
and Damping in a Linear Focusing Channel.
Darwin Energy Paradoxes.
No Bootstrap Spaceships via Magnets in Electric Fields.
No Bootstrap Spaceships, longer review.
Onoochin's Paradox.
Cullwick's Paradox:
Charged Particle on the Axis of a Toroidal Magnet.
Momentum in a DC Circuit.
McKenna's Paradox: Charged Particle Exiting the
Side of A Solenoid Magnet.
Slepian's Electromagnetic Spaceship.
Tuval's Electromagnetic Spaceship.
CapacitorDriven Railgun: Magnetic Fields Doing Work.
Ampère's Hairpin Spaceship.
Electromagnetic Helicopter?
Electromagnetic SelfForce on a Hemispherical
Cavity.
Little's Paradox.
McClymer's Electromagnetic Spaceship.
Engelhardt's Electromagnetic Spaceship.
Electromagnetic Field Momentum.
[This was the beginning of my ongoing fascination with "hidden" momentum.]
An exchange of letters on
electromagnetic field momentum.
Four Expressions for Electromagnetic Field Momentum.
Electromagnetic Momentum of a Capacitor
in a Uniform Magnetic Field.
On the Definition of "Hidden" Momentum.
"Hidden" Momentum in a Plane Electromagnetic Wave.
"Hidden" Momentum in a Compressed Rod?
"Hidden" Momentum in an Isolated Brick?
Force and Torque while Frying an Egg.
"Hidden" Momentum of a Steady Current Distribution in a System at "Rest".
"Hidden" Momentum in a Current Loop.
"Hidden" Momentum in a Coaxial Cable.
Flow of Energy and Momentum in a Coaxial Cable.
J.J. Thomson and "Hidden" Momentum.
"Hidden" Momentum in a Magnetized Toroid.
"Hidden" Momentum in an e+e Pair.
"Hidden" Momentum in a Charged, Rotating
Cylinder.
Abraham, Minkowski and "Hidden" Mechanical Momentum.
Bibliography on the AbrahamMinkowski Debate.
Mansuripur's Paradox.
Feynman Cylinder Paradox.
Ph501 Problem sets:
Set 1, .ps version.
(For lectures 1 and 2).
Set 2, .ps version.
(For lectures 3 and 4).
Set 3, .ps version.
(For lectures 5 and 6).
Set 4, .ps version.
(For lectures 7 and 8).
Set 5, .ps version.
(For lectures 9 and 10).
Set 6, .ps version.
(For lectures 11 and 12).
Set 7, .ps version.
(For lectures 13 and 14).
Set 8, .ps version.
(For lectures 15 and 16).
Set 9, .ps version.
Handwritten version (For lectures 17 and 18).
Set 10, .ps version.
Handwritten version (For lectures 19 and 20).
Set 11, .ps version.
Handwritten version (For lectures 21 and 22).
Set 12, .ps version.
Handwritten version (For lectures 23 and 24).
Midterm exam, Oct. 2000,
.ps version.
Ph529, Elementary Particle
Physics.
These lectures, written in the 1980's, give a sense of how the Standard Model
came to be.
Lecture 1, Why High Energy?
Lecture 2, History: The Strong Interaction.
Lecture 3, History: Electromagnetic and Weak
Interactions.
A Simplifed View of the HiggsYukawa Mechanism.
Lecture 4, Detecting Elementary Particles.
Lecture 5, The Electromagnetic Structure of
Matter.
Lecture 6, Elastic Scattering of Electrons
and Hadrons.
Lecture 7, continuation of Lecture 6.
Lecture 8, Inelastic Electron Scattering.
Lecture 9, Invariance Principles and
Conservation Laws.
Lecture 10, Charge Conjugation, Isospin,
etc.
Lecture 11, 3Body Decays, PartialWave
Analysis.
Lecture 12, Phenomenology of the Strong
Interaction at High Energies.
Lecture 13, The Quark Model.
Lecture 14, The Quark Model, II.
Lecture 15, Heavy Quark States.
Lecture 16, The Weak Interaction.
Lecture 17, Weak Interactions, II.
Lecture 18, CP Violation.
CP Violation in the BMeson System.
A Primer on CP Violation in the BMeson System.
Lecture 19, Neutrino Interactions.
Do Neutrino Oscillations Conserve Energy?
Lecture 20, The Need for a Better Theory.
Lecture 21, The GlashowWeinbergSalam Model.
Lecture 22, Test of the
GlashowSalamWeinberg Model.
Lecture 23, Quantum Chromodynamics.
Lecture 24, Speculations.
Download
Aladdin Ghostscript to view .ps files.
Visit the
Tucows website for an extensive collection of browser utilities.
The Feynman Lectures
on Physics.
Notes from a course by Feynman on
Advanced Quantum Mechanics (1966).
Notes from a course by Feynman on
Solid State Physics (1967).
Notes from a course by Feynman on
Relativistic Quantum Mechanics (1967).
Notes from a course by Feynman on
Elementary Particle Physics (1969).
Gerard 't Hooft's site on
how to become a theoretical physicist in your "spare" time.
How to become a GOOD Theoretical Physicist.
Download an interactive
Radiation Simulator,
by Tsumoru Shintake.
Version on my site.
Click on image near bottom of page. I recommend turning
off the auxiliary windows, and turning on "Plot Wavefront" under "View",
"Field Plot."
Note that you can set the velocity of the charge to be greater
than 1 => faster than light.
 The classic textbook illustration of how yanking a charge causes radiation
can be nicely simulated by choosing "Setup", "Trajectory", Line", velocity = 0.1,
start = 0.05, stop = 0.05.
 For a dipole radiator, try "Setup", "Trajectory", "Dipole Oscillation",
velocity = 0.8, amplitude = 0.02.
 For Ĉerenkov radiation, try "Setup", "Trajectory", Line", velocity = 1.5,
start = 1.0, stop = 1.0. You may want to turn off "Plot Electric Field Lines"
for this.
A collection of Java applets
on physics.
The Karlsruhe Physics Course.
Why an Antenna Radiates, by Ken Macleish. Caveat Emptor.
Thinking about Physics, from U. Amherst.
Physics Central, from the APS.
MIT Physics 8.07, E&M, course page.
Harvard Physics 153, E&M, course page.
Chaos on the Web, Caltech PH161, by Michael Cross.
The Chaos Hypertextbook.
Applications of Classical Physics, Caltech PH136, by Roger Blandford,
Kip Thorne and David Stevenson.
Modern Problems in Classical Electrodynamics, by Charles A. Brau.
Elektrodynamik, by Martin Zirnbauer. Maxwell's
equations via chains and differential forms (2.4MB, in German).
.pdf version.
Other physics courses from U. Cologne.
Physics Problem of the Week, from David Morin.
Physics Questions/Problems, from Yakov Kantor.
Physics Problems by Akakii Melikidze.
The delightful
Math Pages includes a
Physics page.
Boston Area Undergraduate Physics Competition.
The Physics Professor's Ultimate Resources.
Physics Quiz by Juergen Giesen.
Visual Physics Question of the Week.
Physics Problems by University of Oregon Physics Students.
Duke Physics Challenges by Henry Greenside.
Physics of the Outdoors by Steven van Roode.
The AutoMechanics of Newton's Laws of Motion.
The Last Word by New Scientist magazine.
Physics Articles, from the Nobel Foundation.
General Interest Articles, from NIST.
Links to
Educational Sites, from LBNL.
ProSEDS. NASA web on power generation by a satellite tether.
The Great Magnet, the Earth. NASA web page on planetary magnetism.
When North Goes South. LANL web page on terrestrial magnetism.
AetherCzar, electromagnetic blog by H.G.~Schantz.
The Sand Mouse Web Page.
GrayLit Network, access to US government technical reports.
The Museum of Hoaxes.
The Museum of
Unworkable Devices.
Ideal Scientific
Equipment.
"The Alternative
View" by John G. Cramer.
Quantum Philosopy Theories.