Ciro Santilli @cirosantilli 37

The only isotope found on Earth because it occurs as part of the uranium 238 decay chain, i.e., it is not a primordial nuclide.

Interestingly it is a bit less stable than other isotopesL such as Polonium-208 (3 y) and Polonium-209 (124 y), but those aren't in any Earthly radioactive chain so they don't show up on Earth.

A really good option to store educational media such as images and video!

Shame that like the rest of Wikimedia, their interface is so clunky and lacking obvious features.

Gun-type fission weapons are the simplest approach and they work with Uranium-235 bombs as you can ignite it with just one explosion.

But Gun-type fission weapons don't work with plutonium, and weapon grade Plutonium is cheaper than weapon grade Uranium, so it wasn't much used.

ALSA can be thought as analogous to physical wires linking up machines.

Except that instead of machines, you have separate programs. One such typical link is:

The advantage of this setup is that separate programs can collaborate to make complex sounds.

The disadvantage of this setup is that it makes it very hard to reproduce results, you basically need a Docker image with the exact same version of everything. And some script to launch and connect all programs correctly.

Some composition systems like LMMS reduce that problem by having synthesizers as plugins, so that you don't have to setup any connections yourself.

aconnect vmpk hello world: askubuntu.com/questions/34391/virtual-midi-piano-keyboard-setup/1298026#1298026

This is a good initiative. It doesn't go nearly as deep as it needs to go to fix students must have a flexible choice of what to learn, but it is a start!

Followup to Quantum field theory lecture by Tobias Osborne (2017).

When the word "advanced" precedes QFT, you know that the brainrape is imminent!!!

Big goal: explain the Standard Model.

Discovered by Marie Curie when she noticed that there was some yet unknown more radioactive element in their raw samples, after uranium and polonium, which she published 6 months prior, had already been separated. Published on December 1989 as: Section "Sur une nouvelle substance fortement radio-active, contenue dans la pechblende".

The uranium 238 decay chain is the main source of naturally occurring radium.

As of 2020, Ciro Santilli is getting excited about quantum computing, which is a deep tech field.

He's a bit lazy to explain why here, but Googling will be more than enough.

There is a risk it will fizzle and the bubble pop, like any revolution.

But recent developments are making it too exciting to ignore.

Really weird and obscure company, good coverage: thequantuminsider.com/2020/02/06/quantum-computing-incorporated-the-first-publicly-traded-quantum-computing-stock/

Publicly traded in 2007, but only pivoted to quantum computing much later.

Social media:

2022 page: www.cs.ox.ac.uk/teaching/courses/2022-2023/quantum/ (archive). Assignments are available:

2022 lecturer: Aleks Kissinger

The course would be better named ZX-calculus as it appears to be the only subject covered.

Group of all permutations.

To Ernest Lawrence for the cyclotron.

It is quite amazing to read through books such as The Supermen: The Story of Seymour Cray by Charles J. Murray (1997), as it makes you notice that earlier CPUs (all before the 70's) were not made with integrated circuits, but rather smaller pieces glued up on PCBs! E.g. the arithmetic logic unit was actually a discrete component at one point.

The reason for this can also be understood quite clearly by reading books such as Robert Noyce: The Man Behind the Microchip by Leslie Berlin (2006). The first integrated circuits were just too small for this. It was initially unimaginable that a CPU would fit in a single chip! Even just having a very small number of components on a chip was already revolutionary and enough to kick-start the industry. Just imagine how much money any level of integration saved in those early days for production, e.g. as opposed to manually soldering point-to-point constructions. Also the reliability, size an weight gains were amazing. In particular for military and spacial applications originally.

Variable resistance element.

Lecture notes that were apparently very popular at Cornell University. In this period he was actively synthesizing the revolutionary bullshit Richard Feynman and Julian Schwinger were writing and making it understandable to the more general physicist audience, so it might be a good reading.

Oh yes, see also: Dirac equation vs quantum electrodynamics.