classical

The first lecture of Leonard Susskind's Stanford Continuing Studies course on modern physics, beginning with classical mechanics. It is the start of a six-quarter sequence on the theoretical foundations of physics.

A detailed 40-minute explanation of the ultraviolet catastrophe, covering Rayleigh and Jeans' classical treatment of blackbody radiation and Planck's quantum hypothesis. It follows the Eisberg and Resnick textbook treatment.

The first of Richard Feynman's 1964 Cornell Messenger Lectures, The Character of Physical Law, focusing on the law of gravitation. Feynman builds up from planetary motion to the nature of physical laws.

David Tong, a Cambridge theoretical physicist, explains at the Royal Institution that the fundamental building blocks of nature are quantum fields rather than particles. He covers what we know about these fields and how they fit into the Standard Model.

Physicist Carlo Rovelli gives a public lecture at the Royal Institution on how our understanding of time has changed, from Boltzmann and Einstein to quantum theory and loop quantum gravity. He blends physics, philosophy and art to argue that time is stranger than everyday intuition suggests.

Sean Carroll introduces his video series on the biggest ideas in physics, such as symmetry, space and matter, as informal discussions with follow-up Q&A videos. This is the short opening video of the series.

Andrej Karpathy builds the GPT tokenizer from scratch, implementing byte pair encoding along with encode and decode. He shows how many odd LLM behaviors trace back to tokenization, and covers Unicode byte encodings along the way.

Harvard Belfer Center lecture by Matthew Bunn explaining how nuclear bombs work, including fission and fusion weapons and which parts of bomb-making are hard. It is part 1 of 2 in the Nuclear 101 series.

Leo Dirac explains how transformer models have replaced LSTMs in NLP. He gives background from bag of words through RNNs and LSTMs, then a technical deep dive into multi-headed self-attention and positional encoding, with sample code.

Eric Weinstein's roughly three-hour presentation of Geometric Unity, his proposed theory unifying physics, given as a special episode of The Portal. It includes clarifications at the end.

A 78-minute Richard Feynman lecture of anecdotes about working at Los Alamos on the Manhattan Project, followed by about ten minutes of audience Q&A in which he tells three safe-cracking stories.

The first lecture of Stanford's Natural Language Processing with Deep Learning course, taught by Chris Manning and Richard Socher. It introduces NLP and word vectors, including SVD, skip-gram, CBOW, negative sampling and word2vec.

A segment from Carl Sagan's original Cosmos explaining the fourth spatial dimension through analogy with a two-dimensional world and shadow projection.

Peter Norvig's UBC distinguished lecture on how massive amounts of simple data, such as for language modeling, can yield understanding that hand-built models could not.

A one-minute clip of Richard Feynman describing the scientific method: guess a law, compute its consequences, and compare with experiment. If it disagrees with experiment, it is wrong.

Douglas Hofstadter lectures at Uppsala University on how analogy and daring thinking drove Einstein's discovery of light quanta. He argues deep insight in physics comes from imaginative leaps rather than rigid logic.

Leonard Susskind's Santa Fe Institute talk on the arrow of time: why the past differs from the future when physics equations are time-symmetric. He covers entropy, cosmology and Boltzmann brains.

Nathan Kutz presents the spatio-temporal dynamics of rotating detonation rocket engines, including combustion fronts that behave like solitons. He shows a bifurcation analysis of a multiscale model that captures the main features.

A one-minute clip from Richard Feynman's 1979 Auckland lecture in which he answers whether you see an object or only its light. It is a short, playful take on perception and on the use of philosophy.

Geoffrey Hinton gives an MIT talk on what is wrong with convolutional neural networks and introduces his capsules project. The description points to the capsule network papers.

The first lecture of Stanford's CS231n course on convolutional neural networks for visual recognition. It surveys the history and key challenges of computer vision, from the Cambrian explosion and Hubel and Wiesel to ImageNet.

A short clip of Richard Feynman on the difference between merely knowing how to reason mathematically and understanding why physical theories work. He discusses holding multiple equivalent ideas and guessing new laws.

Part 2 of Richard Feynman's Messenger Lectures at Cornell, The Character of Physical Law, on the relation of mathematics to physics. He explains why understanding nature requires mathematics.

The first of Richard Feynman's 1964 Messenger Lectures at Cornell, 'The Character of Physical Law', covering the law of gravitation. Feynman traces the history from Kepler and Newton to the universality of the inverse-square law. The recording is an older one with weak audio.

A recording of Richard Feynman's talk on the possibilities of manipulating matter at very small scales, widely seen as an early vision of nanotechnology. This is a later version of his 1959 "There's Plenty of Room at the Bottom" lecture.

A clip of Richard Feynman contrasting the Greek and Babylonian traditions of mathematical reasoning. It compares the axiomatic approach of mathematicians with how physicists use mathematics.

Royal Institution lecture by Dr Kate Lancaster on the most powerful lasers in the world and the extreme conditions they create. It includes live demonstrations and covers applications from industry to fusion.

An excerpt of Richard Feynman's 1985 lecture Q&A about whether machines can think. He discusses the difficulty of defining what computers can never do and compares machine intelligence to machines that don't copy animals.

A talk by Eric Weinstein on gauge theory and its possible application to economics and inflation. It proposes extending the Wu-Yang dictionary into a geometric tool beyond physics.

Andrej Bauer's IAS talk introduces constructive mathematics and what it feels like to do mathematics without excluded middle. It is framed as a tour for classical mathematicians.