Ciro Santilli @cirosantilli 40

The "greatest common divisor" of two integers $x$ and $y$, denoted $\text{gdc}(x,y)$ is the largest natural number that divides both of the integers.

For example, $\text{gdc}(8,12)$ is 4, because:

Unfortunately, physicists and mathematicians keep using Greek letters in their formulas, so we just have to learn them.

A helpful way to remember is to learn a bit of their history/pronunciation: Section "Historical correspondence between Latin and Greek".

To learn the greek letters if you have a base latin alphabet, you must learn the sound of each letter, and which Latin letters they correspond to.

Symbols that look like Greek letters but are not Greek letters:

Is Ciro Santilli crazy (he is, but for this point specifically), or do many/most Greek letters represent the mouth position used in the pronunciation of the letter?

One reasonable and memorable approximation excluding any fine structure is:see for example example: hydrogen 1-2 spectral line.

Hmmm, he does not know how to spell guerilla? sic? www.quora.com/What-is-the-correct-spelling-guerilla-or-guerrilla

Note to self: if you are going to commit a crime, don't publish your plans online.

Ross Ulbricht's diaries come to mind.

That's how Russian shadow library maintainers do it, they know how to crime good old Russians. Maybe there is a good thing about having dictatorships in the world that give zero fucks about American copyright laws. There will always be some random Russian academic who will implement this and not go to jail. Maybe it's even state sponsored.

The guitar is a highly imperfect instrument if compared to something like a piano, which is much more mathematically elegant.

However, Ciro Santilli just loves this imperfection for some reason, especially in the case of the electric guitar.

Bending, sliding and strumming just feel to good to not have.

And Ciro sucks are doing things in parallel, so the more single threaded approach of the guitar fits his brain/abilities better.

For those reasons, the electric guitar is Ciro's favorite musical instrument.

In some contexts, we want to observe what happens for a given fixed magnetic field strength on a specific plate (thus $t$ and $n$ are also fixed).

In those cases, it can be useful to talk about the "Hall resistance" defined as:So note that it is not a "regular resistance", it just has the same dimensions, and is more usefully understood as a proportionality constant for the voltage given an input $I_x$ current:

This notion can be useful because everything else being equal, if we increase the current $I_x$, then $V_y$ also increases proportionally, making this a way to talk about the voltage in a current independent manner.

And this is particularly the case for the quantum Hall effect, where $R_{xy}$ is constant for wide ranges of applied magnetic field and TODO presumably the height $t$ can be made to a single molecular layer with chemical vapor deposition of the like, and if therefore fixed.

Analogous to what the Euler-Lagrange equation is to Lagrangian mechanics, Hamilton's equations give the equations of motion from a given input Hamiltonian:So once you have the Hamiltonian, you can write down this system of partial differential equations which can then be numerically solved.

The B Reactor of the facility produced the plutonium used for Trinity and Fat Man, and then for many more thousand bombs during the Cold War. More precisely, this was done at

Located in Washington, in a dry place the middle of the mountainous areas of the Western United States, where basically no one lives. The Columbia river is however nearby, that river is quite large, and provided the water needed by their activities, notably for cooling the nuclear reactors. It is worth it having look on Google Maps to get a feel for the region.

Unlike many other such laboratories, this one did not become a United States Department of Energy national laboratories. It was likely just too polluted.

Bibliography:

Head of the theoretical division at the Los Alamos Laboratory during the Manhattan Project.

Richard Feynman was working under him there, and was promoted to team lead by him because Richard impressed Hans.

He was also the person under which Freeman Dyson was originally under when he moved from the United Kingdom to the United States.

And Hans also impressed Feynman, both were problem solvers, and liked solving mental arithmetic and numerical analysis.

This relationship is what brought Feynman to Cornell University after World War II, Hans' institution, which is where Feynman did the main part of his Nobel prize winning work on quantum electrodynamics.

Hans must have been the perfect PhD advisor. He's always smiling, and he seemed so approachable. And he was incredibly capable, notably in his calculation skills, which were much more important in those pre-computer days.

Based on the Josephson effect. Yet another application of that phenomenal phenomena!

Philosophically, superconducting qubits are good because superconductivity is macroscopic.

It is fun to see that the representation of information in the QC basically uses an LC circuit, which is a very classical resonator circuit.

As mentioned at en.wikipedia.org/wiki/Superconducting_quantum_computing#Qubit_archetypes there are actually a few different types of superconducting qubits:

and hybridizations of those such as:

Input:

Appears to be analogous to the dot product, but also defined for infinite dimensions.