why so cute?
I love math but math does not love me :(
me when it turns out ok in the end
When one searches for Fourier series animations online, these amazing gifs are what they stumble upon.
They are absolutely remarkable to look at. But what are the circles actually doing here?
Your objective is to represent a square wave by combining many sine waves. As you know, the trajectory traced by a particle moving along a circle is a sinusoid:
This kind of looks like a square wave but we can do better by adding another harmonic.
We note that the position of the particle in the two harmonics can be represented as a vector that constantly changes with time like so:
And being vector quantities, instead of representing them separately, we can add them by the rules of vector addition and represent them a single entity i.e:
Source
The trajectory traced by the resultant of these vectors gives us our waveform.
And as promised by the Fourier series, adding in more and more harmonics reduces the error in the waveform obtained.
Have a good one!
**More amazing Fourier series gifs can be found here.
Steller’s Jay. Timelapse
Amalie Emmy Noether was a German mathematician known for her landmark contributions to abstract algebra and theoretical physics. And noether’s theorem is one of the most beautiful equation in all of theoretical physics.
The theorem explains the connection between symmetry and conservation laws.
It is remarkably surprising that there are a lot of people who are not aware of Noether’s contribution to physics.
This video by ‘Looking Glass Universe’ does a good job (but does not cover the math) in explaining the essence of the theorem.
Have fun!