Ruby on Rails React integration Updated 2025-07-16
Integrations React integration:
- github.com/shakacode/react_on_rails: webpack and server-side rendering
- github.com/reactjs/react-rails Official on the React side only. Demo app linked from package: github.com/BookOfGreg/react-rails-example-app and how it fails: github.com/BookOfGreg/react-rails-example-app/issues/30... The related projects section has some good links:
- shakacode/react_on_rails
- github.com/hyperstack-org/hyperstack transpiles Ruby to JavaScript + React. What could possibly go wrong? :-)
Selected Papers on Quantum Electrodynamics by Julian Schwinger (1958) Updated 2025-07-16
Time-independent Schrödinger equation for a free one dimensional particle Updated 2025-07-16
so the solution is:We notice that the solution has continuous spectrum, since any value of can provide a solution.
Project Gutenberg remove line breaks Updated 2025-07-16
Proton-to-electron mass ratio Updated 2025-07-16
Proton VPN Updated 2025-07-16
Python classes Updated 2025-07-16
6 hour lecture, where he tries to explain it to an audience that does not know any modern physics. This is a noble effort.
Part of The Douglas Robb Memorial Lectures lecture series.
Feynman apparently also made a book adaptation: QED: The Strange Theory of Light and Matter. That book is basically word by word the same as the presentation, including the diagrams.
According to www.feynman.com/science/qed-lectures-in-new-zealand/ the official upload is at www.vega.org.uk/video/subseries/8 and Vega does show up as a watermark on the video (though it is too pixilated to guess without knowing it), a project that has been discontinued and has has a non-permissive license. Newbs.
4 parts:This talk has the merit of being very experiment oriented on part 2, big kudos: how to teach and learn physics
- Part 1: is saying "photons exist"
- Part 2: is amazing, and describes how photons move as a sum of all possible paths, not sure if it is relativistic at all though, and suggests that something is minimized in that calculation (the action)
- Part 3: is where he hopelessly tries to explain the crucial part of how electrons join the picture in a similar manner to how photons do.He does make the link to light, saying that there is a function which gives the amplitude for a photon going from A to B, where A and B are spacetime events.And then he mentions that there is a similar function for an electron to go from A to B, but says that that function is too complicated, and gives no intuition unlike the photon one.He does not mention it, but P and E are the so called propagators.This is likely the path integral formulation of QED.On Quantum Mechanical View of Reality by Richard Feynman (1983) he mentions that is a Bessel function, without giving further detail.And also mentions that:where
m
is basically a scale factor.
such that both are very similar. And that something similar holds for many other particles.And then, when you draw a Feynman diagram, e.g. electron emits photon and both are detected at given positions, you sum over all the possibilities, each amplitude is given by:summed over all possible Spacetime points.This is basically well said at: youtu.be/rZvgGekvHes?t=3349 from Quantum Mechanical View of Reality by Richard Feynman (1983).TODO: how do electron velocities affect where they are likely to end up? suggests the probability only depends on the spacetime points.Also, this clarifies why computations in QED are so insane: you have to sum over every possible point in space!!! TODO but then how do we calculate anything at all in practice? - Part 4: known problems with QED and thoughts on QCD. Boring.
Richard Feynman Quantum Electrodynamics Lecture at University of Auckland (1979) uploaded by Trev M (2015)
Source. Single upload version. Let's use this one for the timestamps I guess.- youtu.be/Alj6q4Y0TNE?t=2217: photomultiplier tube
- youtu.be/Alj6q4Y0TNE?t=2410: local hidden-variable theory
- youtu.be/Alj6q4Y0TNE?t=6444: mirror experiment shown at en.wikipedia.org/w/index.php?title=Quantum_electrodynamics&oldid=991301352#Probability_amplitudes
- youtu.be/Alj6q4Y0TNE?t=7309: mirror experiment with a diffraction grating pattern painted black leads to reflection at a weird angle
- youtu.be/Alj6q4Y0TNE?t=7627: detector under water to explain refraction
- youtu.be/Alj6q4Y0TNE?t=8050: explains biconvex spherical lens in terms of minimal times
- youtu.be/Alj6q4Y0TNE?t=8402: mentions that for events in a series, you multiply the complex number of each step
- youtu.be/Alj6q4Y0TNE?t=9270: mentions that the up to this point, ignored:but it should not be too hard to add those
- amplitude shrinks down with distance
- photon polarization
- youtu.be/Alj6q4Y0TNE?t=11697: finally starts electron interaction. First point is to add time of event detection.
- youtu.be/Alj6q4Y0TNE?t=13704: electron between plates, and mentions the word action, without giving a clear enough idea of what it is unfortunately
- youtu.be/Alj6q4Y0TNE?t=14467: mentions positrons going back in time, but does not clarify it well enough
- youtu.be/Alj6q4Y0TNE?t=16614: on the fourth part, half is about frontiers in quantum electrodynamics, and half full blown theory of everything. The QED part goes into renormalization and the large number of parameters of the Standard Model
Fermat's last theorem Updated 2025-07-16
Iterative post-order Updated 2025-07-16
This is the hardest one to do iteratively.
Ladder operator Updated 2025-07-16
www.physics.udel.edu/~jim/PHYS424_17F/Class%20Notes/Class_5.pdf by James MacDonald shows it well.
And then we can prove the ladder properties easily.
The commutator appear in the middle of this analysis.
New Revolutions in Particle Physics by Leonard Susskind (2009) Updated 2025-07-16
Omniscient debugging Updated 2025-07-16
What it adds on top of reverse debugging: not only can you go back in time, but you can do it instantaneously.
Or in other words, you can access variables from any point in execution.
pyenv Updated 2025-07-16
Python
abc
Updated 2025-07-16 Python
ast
Updated 2025-07-16 Python scientific library Updated 2025-07-16
Classification of Pythagorean triples Updated 2025-07-16
Conda Updated 2025-07-16
Conda is like pip, except that it also manages shared library dependencies, including providing prebuilts.
This has made Conda very popular in the deep learning community around 2020, where using Python frontends like PyTorch to configure faster precompiled backends was extremely common.
It also means that it is a full package manager and extremely overbloated and blows up all the time. People should just use Docker instead for that kind of stuff: www.reddit.com/r/learnmachinelearning/comments/kd88p8/comment/keco07k/
You also have to buy a license to use their repos if you are part of a large-enough organization: stackoverflow.com/questions/74762863/are-conda-miniconda-and-anaconda-free-to-use-and-open-source
Python web framework Updated 2025-07-16
There are unlisted articles, also show them or only show them.