Ciro Santilli @cirosantilli 37

In this section we collect results about algebraic equations over more "exotic" fields

Generates numpy/fft_plot.svg, the plot of $2\sin (t)+\cos (4t)$ with 25 points and its DFT.

The output was also uploaded to: commons.wikimedia.org/wiki/File:DFT_2sin(t)_%2B_sin(4t).svg and added to en.wikipedia.org/w/index.php?title=Discrete_Fourier_transform&oldid=1176616763 only to be later removed of course: Deletionism on Wikipedia.

A hard problem ha been found for it, and it was called the "antihydra":

The good:

The bad: everything else. Closed source learning materials + a university-like selection program. Such a waste of efforts that could benefit way more people with more open resources.

meta.mathoverflow.net/questions/4889/request-to-keep-an-eye-out-for-promys-admissions-problems asking to remove PROMYS problems from MathOverflow. And it seems to have been mostly accepted. Newbs. Any maths problem should be allowed to be askeable online. There are no fundamentally new problems, copyright takedown is just silly.

Staring from a triangle wave, this explains why we always get the same musical notes:See also: solving partial differential equations with the Fourier series.

TODO: do higher overtones decay faster in time than the base ones?

You know things are bad when the extracurricular activities are what studnets should actually be doing full time instead!

Discovering them was not so easy because they don't form chemical compounds. So they exist only as gases. And Helium disperses off into space.

Argon was the first to be found by density considerations because it is so abundant on Earth's atmosphere (~1%): Argon is abundant on Earth's atmosphere because it comes from the decay of Potassium-40.

Then basically all of the others were discovered by spectral lines. Helium notably was first found on the Sun like that, and only later on Earth! Thus its name. Pretty cool.