The "stuff" that composes the physical universe: photons, electrons, and the other fundamental particles of the standard model.
Definition Materialism (noun):
The deeply-rooted philosophy or world-view that reality is solely composed of material.
In a certain sense, materialism is the natural conclusion of several hundred years of empirical science →. It serves as a sort of lower-bound for what is known about reality, and by no means should be mistaken for an upper-bound of what can be known. Generally on Transcendental Metaphysics, materialism is treated as an elaborate and compelling mental trap →, but that doesn't make it wrong, in the sense that it is still extremely useful for modeling the physical universe.
These models range across a variety of scales, and at each scale there is a scientific discipline that studies them. What starts off on the desk of the physicist slowly makes its way to the chemist, then the biologist, and so on, until it ends of in the hands of the astronomer [1].
[1]Or the art critic, if you want to make it a joke.
The essays that I have filed here below under [Physics] → are materialistic in the sense that they explicitly limit themselves to a material understanding of reality [2]. They are not works of science, per se; that I have left to the serious scientists [3]. They conform to no academic standard [4] more rigorous than what I feel won't embarrass me, and I hope (embarrassing or not) you find them delightful.
[2]If you want the antithesis, go walk up the holy mountain →.
[3]And art critics. Though to be honest, I wouldn't take any serious art critic seriously; those who can, do, and those who can't make light of it. I hope you never catch me with an over-inflated sense of self-importance.
[4]In a previous career, I considered pursuing academic research. I got just close enough to get a lively distaste for the academia's bullshit [4-1], and when I found myself fantasizing about re-doing empiricism from scratch, I figured this was not for me [4-2].
[4-1]Quick story: I published a paper [4-1-1], and when I took the finished draft to the grad student I worked under, it had six citations. Why? Because I only read and found useful six other papers. He looked at it and said "oh, that's not gonna do", and by the time it found its way into the conference proceedings, it had 33 citations, most of which were there for 'prior work'. As they say, when you make a metric a goal, it ceases to be a useful metric.
[4-1-1]Which got me an Erdös number of 4, an achievement I am disproportionately proud of.
[4-2]I also got a job that paid real money, and found that I could do things with real money. And besides, it turns out that the cutting edge of science is not inside the ivory tower.