Ciro Santilli @cirosantilli 40

In special relativity, it is impossible to travel faster than light.

One argument of why, is that if you could travel faster than light, then you could send a message to a point in Spacetime that is spacelike-separated from the present. But then since the target is spacelike separated, there exists a inertial frame of reference in which that event happens before the present, which would be hard to make sense of.

Even worse, it would be possible to travel back in time:

Uses telephone lines, and therefore were still usable much much after the Internet made them obsolete, which is quite funny.

An alloy of iron and carbon. Because such allys have had such incredible historical importance due to their different properties, different phases of Fe-C have well known names such as steel

The wiki comments: en.wikipedia.org/w/index.php?title=Ferromagnetism&oldid=965600553#Explanation

I think they are a tool to calculate the probability of different types of particle decays and particle collision outcomes. TODO Minimal example of that.

And they can be derived from a more complete quantum electrodynamics formulation via perturbation theory.

Can be used for all of quantum electrodynamics, weak interaction and quantum chromodynamics.

At Richard Feynman Quantum Electrodynamics Lecture at University of Auckland (1979), an intuitive explanation of them in termes of sum of products of propagators is given.

A ring where multiplication is commutative and there is always an inverse.

A field can be seen as an Abelian group that has two group operations defined on it: addition and multiplication.

And then, besides each of the two operations obeying the group axioms individually, and they are compatible between themselves according to the distributive property.

Basically the nicest, least restrictive, 2-operation type of algebra.

Examples:

Hello world adapted from: github.com/liabru/matter-js/wiki/Getting-started/1d138998f05766dc4de0e44ae2e35d03121bb7f2

Also asked at: stackoverflow.com/questions/28079138/how-to-make-minimal-example-of-matter-js-work/76203103#76203103

Renderer questions:

Ciro Santilli used to use file managers in the past.

But he finally converted to a shell cd aliases that auto-ls: github.com/cirosantilli/dotfiles/blob/a51bcc324f0cff0eddd4c3bb8654ec223a0adb7b/home/.bashrc#L1058

Each of the omics studies a subset of molecular biology with a data intensive and broad point of view that tries to understand global function or organisms, trying to understand what every biologically relevant molecule does as part of the hole metabolism.

The main omics are:

Omics might be stamp collecting, but maybe it is a bit more like Trading card game/Magic: The Gathering collecting, in which the cards that you are collecting actually have specific uses and interactions, especially considering that most metabolic pathways are analogous across many species.

Has the best opening scene of all time.

Top quotes:

In the context of wave-like equations, an open-boundary condition is one that "lets the wave go through without reflection".

This condition is very useful when we want to simulate infinite domains with a numerical method. Ciro Santilli wants to do this all the time when trying to come up with demos for his physics writings.

Here are some resources that cover such boundary conditions:

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