The Unreasonable Effectiveness of the Fourier Transform
Notes from Joshua Wise's talk at Teardown 2025.

Here are a few resources from my talk.
- Here is a PDF of my slides, if you
wanted to refer to anything in specific.
- Here is the Jupyter notebook that I
used to produce all of the zillions of plots. I do not claim that it is
good code, but it is code.
- The OFDM patent is US3488445A, filed
in 1966, expired in 1987.
- Here is Eugene Wigner's
original discussion, "The Unreasonable Effectiveness of Mathematics in the
Natural Sciences". There are many good follow-ons to this, too.
- Here is the paper
on how to estimate both carrier offset and time offset at the same
time. I implemented it by typing in the algorithm, and it worked, but if you
understand it and can explain it to me please let me know.
- Here is the DVB-T decoder that I
wrote. I do not claim that it is the right way to do any of these
things, but it is a way to do these things.
- Finally, here is an absolutely fantastic
video that breaks down the implementation of the Fast Fourier
Transform algorithm. I watch it every year or two.
When the video of my talk becomes available, I will link it here,
too.
Thanks so much for coming! Please let me know if you have feedback on
this. I'd love to hear what you thought.