QED (book)
Encyclopedia
QED: The Strange Theory of Light and Matter is an adaptation for the general reader of four lectures on quantum electrodynamics
Quantum electrodynamics
Quantum electrodynamics is the relativistic quantum field theory of electrodynamics. In essence, it describes how light and matter interact and is the first theory where full agreement between quantum mechanics and special relativity is achieved...

 (QED) by Richard Feynman
Richard Feynman
Richard Phillips Feynman was an American physicist known for his work in the path integral formulation of quantum mechanics, the theory of quantum electrodynamics and the physics of the superfluidity of supercooled liquid helium, as well as in particle physics...

 (1918-1988).

QED was designed to be a popular science
Popular science
Popular science, sometimes called literature of science, is interpretation of science intended for a general audience. While science journalism focuses on recent scientific developments, popular science is broad-ranging, often written by scientists as well as journalists, and is presented in many...

 book in a witty style with a very small amount of quantum-mechanical mathematics
Mathematics
Mathematics is the study of quantity, space, structure, and change. Mathematicians seek out patterns and formulate new conjectures. Mathematicians resolve the truth or falsity of conjectures by mathematical proofs, which are arguments sufficient to convince other mathematicians of their validity...

. It is aimed at teaching an educated general public audience an understanding of what's going on behind the calculations rather than teaching how to do the calculations. It was first published in 1985 by the Princeton University Press
Princeton University Press
-Further reading:* "". Artforum International, 2005.-External links:* * * * *...

.

The book

Much of Feynman's discussion springs from an everyday phenomenon: the way any transparent sheet of glass partly reflects any light shining on it. Feynman also pays homage to Isaac Newton
Isaac Newton
Sir Isaac Newton PRS was an English physicist, mathematician, astronomer, natural philosopher, alchemist, and theologian, who has been "considered by many to be the greatest and most influential scientist who ever lived."...

's struggles to come to terms with the nature of light.

Feynman's lectures were originally given as the Sir Douglas Robb
George Douglas Robb
Sir George Douglas Robb was a New Zealand surgeon, medical reformer, writer, and university chancellor. He was educated at the Auckland Grammar School and at the University of Otago...

 lectures at the University of Auckland
University of Auckland
The University of Auckland is a university located in Auckland, New Zealand. It is the largest university in the country and the highest ranked in the 2011 QS World University Rankings, having been ranked worldwide...

, New Zealand
New Zealand
New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...

 in 1979. Videotapes of these lectures were made publicly available on a not-for-profit basis in 1996 and more recently have been placed online by the Vega Science Trust.

The book is based on Feynman's delivery of the first Alix G. Mautner Memorial Lecture series for the general public at the University of California, Los Angeles
University of California, Los Angeles
The University of California, Los Angeles is a public research university located in the Westwood neighborhood of Los Angeles, California, USA. It was founded in 1919 as the "Southern Branch" of the University of California and is the second oldest of the ten campuses...

 (UCLA) in 1983. The differences between the book and the original Auckland
Auckland
The Auckland metropolitan area , in the North Island of New Zealand, is the largest and most populous urban area in the country with residents, percent of the country's population. Auckland also has the largest Polynesian population of any city in the world...

 lectures were discussed in June 1996 in the American Journal of Physics
American Journal of Physics
The American Journal of Physics is a monthly, peer-reviewed scientific journal published by the American Association of Physics Teachers and the American Institute of Physics. The editor is Jan Tobochnik of Kalamazoo College.-Aims and scope:...

.

In 2006, Princeton University Press published a new edition with a new introduction by Anthony Zee
Anthony Zee
Anthony Zee is a Chinese American physicist, writer, and currently a professor at the Kavli Institute for Theoretical Physics and the physics department of the University of California, Santa Barbara.Zee obtained his Ph.D. from Harvard in 1970, supervised by Sidney Coleman...

. He introduces Feynman's peculiar take at explaining physics, and cites: "According to Feynman, to learn QED you have two choices: you can go through seven years of physics education or read this book"

The four lectures

1. Introduction
In the first lecture, Feynman describes the basic properties of photon
Photon
In physics, a photon is an elementary particle, the quantum of the electromagnetic interaction and the basic unit of light and all other forms of electromagnetic radiation. It is also the force carrier for the electromagnetic force...

s which acts as a gentle lead-in to the subject (as he colloquially stated before that a science lecture is boring if either it's not using layman terms or saying something upside down). Feynman discusses how to measure the probability that a photon will reflect or transmit through a partially reflective piece of glass.

2. Photons: Particles of Light
In the second lecture, Feynman looks at the different paths a photon can take as it travels from one point to another and how this affects phenomena like reflection
Reflection (physics)
Reflection is the change in direction of a wavefront at an interface between two differentmedia so that the wavefront returns into the medium from which it originated. Common examples include the reflection of light, sound and water waves...

 and diffraction
Diffraction
Diffraction refers to various phenomena which occur when a wave encounters an obstacle. Italian scientist Francesco Maria Grimaldi coined the word "diffraction" and was the first to record accurate observations of the phenomenon in 1665...

.

3. Electrons and Their interactions
The third lecture describes Quantum phenomena such as the famous double-slit experiment
Double-slit experiment
The double-slit experiment, sometimes called Young's experiment, is a demonstration that matter and energy can display characteristics of both waves and particles...

 and Werner Heisenberg
Werner Heisenberg
Werner Karl Heisenberg was a German theoretical physicist who made foundational contributions to quantum mechanics and is best known for asserting the uncertainty principle of quantum theory...

's uncertainty principle
Uncertainty principle
In quantum mechanics, the Heisenberg uncertainty principle states a fundamental limit on the accuracy with which certain pairs of physical properties of a particle, such as position and momentum, can be simultaneously known...

, thus describing the transmission and reflection of photons. It also introduces his famous "Feynman diagram
Feynman diagram
Feynman diagrams are a pictorial representation scheme for the mathematical expressions governing the behavior of subatomic particles, first developed by the Nobel Prize-winning American physicist Richard Feynman, and first introduced in 1948...

s" and how quantum electrodynamics describes the interactions of subatomic particles.

4. Loose Ends
In the fourth lecture, Feynman discusses the meaning of Quantum electrodynamics and some of its problems. He then describes "the rest of physics", giving a brief look at quantum chromodynamics
Quantum chromodynamics
In theoretical physics, quantum chromodynamics is a theory of the strong interaction , a fundamental force describing the interactions of the quarks and gluons making up hadrons . It is the study of the SU Yang–Mills theory of color-charged fermions...

, the weak interaction
Weak interaction
Weak interaction , is one of the four fundamental forces of nature, alongside the strong nuclear force, electromagnetism, and gravity. It is responsible for the radioactive decay of subatomic particles and initiates the process known as hydrogen fusion in stars...

 and gravity
Gravitation
Gravitation, or gravity, is a natural phenomenon by which physical bodies attract with a force proportional to their mass. Gravitation is most familiar as the agent that gives weight to objects with mass and causes them to fall to the ground when dropped...

, and how they relate to quantum electrodynamics.

External links

  • Feynman QED lectures in New Zealand - The Tuva Trader, DVD
    DVD
    A DVD is an optical disc storage media format, invented and developed by Philips, Sony, Toshiba, and Panasonic in 1995. DVDs offer higher storage capacity than Compact Discs while having the same dimensions....

    s and Vega Science Trust streaming video.
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