After Feynman's death, scholars studying the historical development of nanotechnology have concluded that his actual role in catalyzing nanotechnology research was limited, based on recollections from many of the people active in the nascent field in the 1980s and 1990s.

In the 1 February 2007 issue of Nature, David Leigh, a professor at the University of Edinburgh, announced the creation of a nano-device based on Feynman's thought experiment.

While Dirac's criticism was based on the procedure of renormalization itself, Feynman's criticism was very different.

The definitions fall in two different classes: the constructions derived from Wiener's theory yield an integral based on a measure ; whereas the constructions following Feynman's path integral do not.

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 ( UCLA ) in 1983.

Feynman's Lost Lecture: The Motion of Planets Around the Sun is a book based on a lecture by Richard Feynman.

Figure 4: An example, based on one of Feynman's examples, where Faraday's law does not work.

Dyson is best known for demonstrating in 1949 the equivalence of the formulations of quantum electrodynamics that existed by that time – Richard Feynman's diagrams, on the one hand, and, on the other, the operator method developed by Julian Schwinger and Sin-Itiro Tomonaga.

Based on Richard Feynman's vision of miniature factories using nanomachines to build complex products ( including additional nanomachines ), this advanced form of nanotechnology ( or molecular manufacturing ) would make use of positionally-controlled mechanosynthesis guided by molecular machine systems.

* Feynman's New Zealand lectures on QED for non-physicists

Feynman's suspicions were corroborated by General Kutyna, also on the commission, who cunningly provided Feynman with a broad hint by asking about the effect of cold on O-ring seals after mentioning that the temperature on the day of the launch was far lower than had been the case with previous launches: below freezing at 28 or 29 Fahrenheit (− 2. 2 to − 1. 6 ° C ); previously, the coldest launch had been at 53 ° F ( 12 ° C ).

Much of Feynman's discussion springs from an everyday phenomenon: the way any transparent sheet of glass partly reflects any light shining on it.

Furthermore, despite Feynman's machine doing useful work in lifting the mass, using Brownian motion to power a molecular level machine does not provide any insight on how that power ( or potential energy of the lifted weight, m ) can be used to perform nanoscale tasks.

The potential of very small machines was appreciated before the technology existed that could make them — see, for example, Richard Feynman's famous 1959 lecture There's Plenty of Room at the Bottom.

Feynman's investigation eventually suggested to him that the cause of the Challenger disaster was the very part to which NASA management so mistakenly assigned a safety factor.

Maxwell's Demon is well described elsewhere, and a slightly different interpretation of Richard Feynman's ratchet is given here.

This is a tribute to Richard Feynman's statement, " I have approximate answers and possible beliefs and different degrees of certainty about different things, but I'm not absolutely sure of anything and there are many things I don't know anything about ".

If a photon moves from one place and time – in shorthand, A – to another place and time – shorthand, B – the associated quantity is written in Feynman's shorthand as P ( A to B ).

Use of the term in computer programming probably derives from Richard Feynman's characterization of certain practices as cargo cult science.

Feynman's rules obtained from this functional are the following

Another book released in March 2011 was entitled, Quantum Man: Richard Feynman's Life in Science, and a new book released in January 2012, is entitled, A Universe from Nothing: Why There is Something Rather than Nothing, with an afterword by Richard Dawkins.

The Hartle-Hawking state is the wave function of the Universe – a notion meant to figure out how the Universe started – that is calculated from Feynman's path integral.

Functional integrals arise in probability, in the study of partial differential equations and in Feynman's approach to the quantum mechanics of particles and fields.

In the Hamiltonian approach to quantum field theory, the S-matrix may be calculated as a time-ordered exponential of the integrated Hamiltonian in the interaction picture ; it may be also expressed using Feynman's path integrals.

Although both Feynman's heuristic and pictorial style of dealing with the infinities, as well as the formal methods of Tomonaga and Schwinger, worked extremely well, and gave spectacularly accurate answers, the true analytical nature of the question of " renormalizability ", that is, whether ANY theory formulated as a " quantum field theory " would give finite answers, was not worked-out till much later, when the urgency of trying to formulate finite theories for the strong and electro-weak ( and gravitational interactions ) demanded its solution.

Robert Oppenheimer, in particular, was persuaded by Dyson that Feynman's new theory was as valid as Schwinger's and Tomonaga's.

In 1996, Juan Parrondo and Pep Español used a variation of the above device in which no ratchet is present, only two paddles, to show that the axle connecting the paddles and ratchet conducts heat between reservoirs ; they argued that although Feynman's conclusion was correct, his analysis was flawed because of his erroneous use of the quasistatic approximation, resulting in incorrect equations for efficiency.

Dawkins offers several examples of petwhacs in the book, two of which are the bedside clock of a woman ( Richard Feynman's wife ) stopping exactly when she died, and a psychic who stops the watches of his television audience.

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 ".

There are two thought experiments that form the historical basis for molecular machines: Maxwell's demon and Feynman's Ratchet ( or Brownian ratchet ).

The difference between Feynman's and Gell-Mann's approaches reflected a deep split in the theoretical physics community.

His fellow commission members were alarmed by Feynman's dissent, and it was only after much petitioning that Feynman's minority report was included at all.

Feynman's lectures were originally given as the Sir Douglas Robb lectures at the University of Auckland, New Zealand in 1979.

Since this picture was first developed by Ernst Stueckelberg, and acquired its modern form in Feynman's work, it is called the Feynman-Stueckelberg interpretation of antiparticles to honor both scientists.

The theme of the event was Feynman's Vision: The Next 50 Years.

Dyson's paper and also his lectures presented Feynman's theories of QED ( quantum electrodynamics ) in a form that other physicists could understand and undoubtedly facilitated the physics community's acceptance of Feynman's work.

This work greatly extended the range of applicability of Feynman's method.

Related to the many-worlds idea are Richard Feynman's multiple histories interpretation and H. Dieter Zeh's many-minds interpretation.

Nobody has yet attempted to implement this thought experiment, although it has been noted that some types of biological enzymes and enzyme complexes ( especially ribosomes ) function chemically in a way close to Feynman's vision.

The first challenge involved the construction of a tiny motor, which, to Feynman's surprise, was achieved by November 1960 by William McLellan, a meticulous craftsman, using conventional tools.

Feynman's stature as a Nobel laureate and as an iconic figure in 20th century science surely helped advocates of nanotechnology and provided a valuable intellectual link to the past.

An alternative formulation of quantum mechanics is Feynman's path integral formulation, in which a quantum-mechanical amplitude is considered as a sum over all possible histories between the initial and final states.

The key components of Feynman's presentation of QED are three basic actions.

( A simplification of Feynman's book.

One of the American physicist Richard Feynman's first projects was to develop technology for electroplating metal onto plastic.

Like Newton's Second law, the Schrödinger equation can be mathematically transformed into other formulations such as Werner Heisenberg's matrix mechanics, and Richard Feynman's path integral formulation.

He brings us behind the scenes of the most intellectual tales as he seeks to " combine Einstein's General Theory of Relativity and Richard Feynman's idea of multiple histories into one complete unified theory that will describe everything that happens in the universe.