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Every mathematician has only a few tricks (2020)

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Re: Every mathematician has only a few tricks (2020)

#21
post #18

Feynman wrote in his autobiography that much of his success came from having different mathematical tricks than most of his peers. So when they were stuck, he could sometimes make progress.

He had many tricks in limited area. All his his tricks were limited to classical calculus and nineteenth-century mathematics. He didn't do anything fancy.

His style was always the same, he just mastered it really well.

Re: Every mathematician has only a few tricks (2020)

#23
post #11
post #9

Earlier quoted context omitted.

For me, it's tracing code/pipelines to figure out how a result was produced, typically in the context of that result being wrong somehow. Go To Definition is the most useful function in any editor. I'm always surprised by how frequently colleagues don't think to do this and are left helpless.

This reminds me of my further theory that everyone needs one 'heavy' and one 'light' technique. The 'light' technique is something that often works well as a heuristic and can be an effective unit of iteration. The 'heavy' technique is something that you can fall back on in difficult cases, something that can reliably solve hard problems, even if it's slow. Sometimes the heavy technique is: just ask someone else. ;)

For me the heavy technique is integer linear programming.

I’m not a software developer anymore.

Re: Every mathematician has only a few tricks (2020)

#24
post #18

Feynman wrote in his autobiography that much of his success came from having different mathematical tricks than most of his peers. So when they were stuck, he could sometimes make progress.

Feynman used to read his own books. When asked he said, "it's all in here". He used to revise and refresh his own understanding.

Re: Every mathematician has only a few tricks (2020)

#25
post #18

Feynman wrote in his autobiography that much of his success came from having different mathematical tricks than most of his peers. So when they were stuck, he could sometimes make progress.

Interestingly, one of his famous tricks of computing complex integrals by parameterizing[1] and then differentiating under the integral is known as “Feynman’s trick” in his honour spite of it having been invented by Euler over 250 years before. [1] https://zackyzz.github.io/feynman.html

A popular naming convention in Mathematics is to name things after the second person to discover them. The first person is Leonhard Euler.

Re: Every mathematician has only a few tricks (2020)

#26
post #11

Earlier quoted context omitted.

This reminds me of my further theory that everyone needs one 'heavy' and one 'light' technique. The 'light' technique is something that often works well as a heuristic and can be an effective unit of iteration. The 'heavy' technique is something that you can fall back on in difficult cases, something that can reliably solve hard problems, even if it's slow. Sometimes the heavy technique is: just ask someone else. ;)

> Sometimes the heavy technique is: just ask someone else. ;) For a lot of people I know, this is the light technique!

You jest, but that's how my sister gets through life, and it's always fascinated me.

She's incredibly intelligent, but more importantly she's a phenomenal social networker. She always has someone to call to ask about any question or solve any problem that comes up in life, and she's great at connecting these people with each other when they have problems of their own - so they all want to help her with whatever she needs, just to gain access to a pool of people they themselves can talk to.

What do you do with a skillset like that? I honestly don't know - something in leadership, probably, something where finding the right people and setting them to work is the most important skill of the job.

Re: Every mathematician has only a few tricks (2020)

#27

My dad (an engineer not a mathematician) would use Newton-Raphson[1] to solve basically any problem that wasn’t very obviously linear. When I was a kid, some of my first programming memories were my dad getting me and my brother to implement Newton-Raphson in basic on an HP85a, getting me to implement Newton-Raphson in rpn on an HP calculator, debugging my dad’s (genuinely revolting) basic program[2] which wouldn’t r…

Relatedly, I've found Newton-Raphson is a great example of an algorithm where Knuth's "I have only proven it correct, not tried it" rears its head very prominently. The obvious implementations can work flawlessly on toy examples and then fail miserably on real-world examples.

Re: Every mathematician has only a few tricks (2020)

#29

Earlier quoted context omitted.

> Sometimes the heavy technique is: just ask someone else. ;) For a lot of people I know, this is the light technique!

You jest, but that's how my sister gets through life, and it's always fascinated me. She's incredibly intelligent, but more importantly she's a phenomenal social networker. She always has someone to call to ask about any question or solve any problem that comes up in life, and she's great at connecting these people with each other when they have problems of their own - so they all want to help her with whatever she n…

That wasn't in jest. I worked in a place where this was a norm. Nothing was properly documented, instead everyone would just ask and answer questions on chats; somehow, this actually kept velocity high.

Found it really hard to adjust to that. I'm the kind of person that prefers to research things on my own, find hard references and understand context. But there, this was the wrong approach.

Re: Every mathematician has only a few tricks (2020)

#30

My dad (an engineer not a mathematician) would use Newton-Raphson[1] to solve basically any problem that wasn’t very obviously linear. When I was a kid, some of my first programming memories were my dad getting me and my brother to implement Newton-Raphson in basic on an HP85a, getting me to implement Newton-Raphson in rpn on an HP calculator, debugging my dad’s (genuinely revolting) basic program[2] which wouldn’t r…

Relatedly, I've found Newton-Raphson is a great example of an algorithm where Knuth's "I have only proven it correct, not tried it" rears its head very prominently. The obvious implementations can work flawlessly on toy examples and then fail miserably on real-world examples.

There's a reason why numeric analysis is still actively studied by research mathematicians. If we could just throw something as simple as newton's method at any nonlinear problem, we'd only need people to learn this once in school and everyone could solve everything.
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