Chapter 8 is incomplete. It says the local area factor "is zero at one single point... and the map uses it to wrap the plane around twice... so local factor never zero is not enough on its own".
"X is false, therefore X implies Y is false". But this is faulty reasoning.
This is really good - miles ahead of almost all other math writing I have read. One particular thing I really liked was the explanation of the determinant. When I was in college I spent a very long time trying to get some intuitive explanation for a determinant of a matrix and the best I could get is that you just multiplied and subtracted some numbers and poof there you go. I KNEW there had to be some more comprehensible explanation and it drove me crazy that people just parroted textbooks without any real understanding.
This reminds me of that silly video everyone was shown in middle school about inverting a sphere :-)
I am very curious how it was written (will there be a write up to the write up?!). It feels likely AI assisted, but this seems to me to be the best possible use of AI -- crunching out a bunch of visualizations of complex ideas so that they are easy to understand just by looking. The writing also feels a little AI written but definitely feels very human-assisted.
I followed very loosely and still got it. Very cool, the kind of math that gets close to feeling like "real life". I was really hoping that your mentions of "solving it by hand" and "you can prove it to yourself by hand" at the end were going to come to some clever maneuver I could do with my own hand (like the physics magnetism hand rule). Still, awesome.
I think the entire post was created by an AI, and I had a similar negative reaction to it. Nevertheless, it's an excellent post with clear explanations of mathematical concepts. This just goes to show how impossible it is to tell the difference between something created by a human and something created by an LLM.
one thing I didn't understand. If the conjecture is false for real numbers, why isn't it false for complex numbers too? Why can't you just take a real number counterexample and use it for complex numbers?
I guess the answer is that a polynomial map whose Jacobian determinant is constant non-zero over the reals may not also be constant non-zero over all the complex numbers.
Also more and more use of an extremely annoying effect: text-heavy animations that reset themselves for no reason while you're trying to read them. Step 11, for instance: no value whatsoever is added by erasing and redrawing that figure.
Still, overall a very nice piece of pedagogy. If you didn't grok determinants before, this will probably help.
"X is false, therefore X implies Y is false". But this is faulty reasoning.
This reminds me of that silly video everyone was shown in middle school about inverting a sphere :-)
I am very curious how it was written (will there be a write up to the write up?!). It feels likely AI assisted, but this seems to me to be the best possible use of AI -- crunching out a bunch of visualizations of complex ideas so that they are easy to understand just by looking. The writing also feels a little AI written but definitely feels very human-assisted.
https://github.com/muchmirul/conjectures/commits/main/
The material however, got fairly dense. After chapter 10, it is no longer "baby" material in my opinion.
but the further into the text, the better the prose
by the end it was great
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good to know that conjecture has been false for real numbers for a while now
I guess the answer is that a polynomial map whose Jacobian determinant is constant non-zero over the reals may not also be constant non-zero over all the complex numbers.
Still, overall a very nice piece of pedagogy. If you didn't grok determinants before, this will probably help.