Hertz electromagnetic wave experiments Updated +Created
Heinrich Hertz's main initial experiment used a spark-gap transmitter. It is not something that transmits recorded sounds like voice: it only transmits noisy beeps. And as such was used for wireless telegraphy.
Video 1.
Hertz Experiment on Electromagnetic Waves by Ludic Science (2015)
Source. Simplified recreation with cheap modern equipment. Uses as transmitter power source both:and the signal is observed on the receiver with a neon lamp
Video 2.
Hertz and Radio waves Explained by PhysicsHigh (2016)
Source. Simple schematics showing the basics of the experiments. No choice of components rationale.
Lagrangian vs Hamiltonian Updated +Created
The key difference from Lagrangian mechanics is that the Hamiltonian approach groups variables into pairs of coordinates called the phase space coordinates:
This leads to having two times more unknown functions than in the Lagrangian. However, it also leads to a system of partial differential equations with only first order derivatives, which is nicer. Notably, it can be more clearly seen in phase space.
The main function of university is sexual selection Updated +Created
This is the actual main function of university for many people as of the 2020s. And it fulfills it quite well. A breeding ground.
In a closely related sense, university is simply a symbol of personal status. Not a place where you go to learn. And especially in the Anglophone world of fancy colleges, university also doubles down as a form of long term luxury hotel. Even if it ends up meaning debt.
There's nothing wrong with sexual selection. This type of natural eugenics is an important part of humankind. It is however just sad that any type of learning falls so much behind. A close second would be fine. But as it stands, it is just too far off.
Theory of everything Updated +Created
As of 2019, the Standard Model and general relativity are incompatible. Once those are unified, we will have one equation to describe the entirety of physics.
There are also however also unsolved problems in electroweak interaction + strong interaction, which if achieved is referred to as a Grand Unified Theory. Reaching a GUT is considered a sensible intermediate step before TOE.
The current state of Physics has been the result of several previous unifications as shown at: en.wikipedia.org/wiki/Theory_of_everything#Conventional_sequence_of_theories so it is expected that this last missing unification is likely to happen one day, potentially conditional on humanity having enough energy to observe new phenomena.
AIDS Updated +Created
Chinese regional cuisine Updated +Created
Probable observation of the Josephson superconducting tunneling effect Updated +Created
Paper by Philip W. Anderson and John M. Rowell that first (?) experimentally observed the Josephson effect.
TODO understand the graphs in detail.
They used tin-oxide-lead tunnel at 1.5 K. TODO oxide of what? Why two different metals? They say that both films are 200 nm thick, so maybe it is:
   -----+------+------+-----
...  Sn | SnO2 | PbO2 | Pb  ...
   -----+------+------------
          100nm 100nm
A reconstruction of their circuit in Ciro's ASCII art circuit diagram notation TODO:
DC---R_10---X---G
There are not details of the physical construction of course. Reproducibility lol.
Figure 1.
Figure 1 of Probable observation of the Josephson superconducting tunneling effect
. TODO what do the dotted lines mean?
Figure 2.
Figure 2 of Probable observation of the Josephson superconducting tunneling effect
.
Svengali Updated +Created
The most awesome systems programmers Updated +Created
Notable mentions:
Other notable people that are likely also awesome but Ciro has less familiarity with their contributions:
Chorus effect Updated +Created
HTML canvas Updated +Created
Allows us to draw with JavaScript pixel by pixel! Great way to create computational physics demos!
Here is an animation demo with some useful controls:
HTML snippet:
new class extends OurbigbookCanvasDemo {
  init() {
    super.init('hello');
    this.pixel_size_input = this.addInputAfterEnable(
      'Pixel size',
      {
        'min': 1,
        'type': 'number',
        'value': 1,
      }
    );
  }
  draw() {
    var pixel_size = parseInt(this.pixel_size_input.value);
    for (var x = 0; x < this.width; x += pixel_size) {
      for (var y = 0; y < this.height; y += pixel_size) {
        var b = ((1.0 + Math.sin(this.time * Math.PI / 16)) / 2.0);
        this.ctx.fillStyle =
          'rgba(' +
          (x / this.width) * 255 + ',' +
          (y / this.height) * 255 + ',' +
          b * 255 +
          ',255)'
        ;
        this.ctx.fillRect(x, y, pixel_size, pixel_size);
      }
    }
  }
}
HTML details tag Updated +Created
Human brain connectome Updated +Created
By cranks:
Human brain research project Updated +Created
ImageNet competition Updated +Created
JavaScript language Updated +Created

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