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Marvelous Arithmetics of Distance

mathenchant.wordpress.com

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Re: Marvelous Arithmetics of Distance

#13
post #12

For another accessible introduction to p-adic numbers, check out Eric Rowland's overview [1]. [1]: https://www.youtube.com/watch?v=3gyHKCDq1YA

It's also not a full introduction, but for those who want to have a taste of p-adic numbers, see 3b1b's video https://www.youtube.com/watch?v=XFDM1ip5HdU which motivates 2-adic numbers. There's also a neat connection between twos complement and 2-adic numbers.

Re: Marvelous Arithmetics of Distance

#14
post #3

I must have missed p-adics in school. This was a fun, interesting, and clear read.

They are typically not taught in school, at least in the US but probably elsewhere too. I don’t even know of a commonly taken undergrad-level course that I’d expect to cover them.

They're often -- but not always -- touched on in advanced undergraduate classes, e.g. after real analysis and abstract algebra. Not every math undergraduate takes number theory these days.

Re: Marvelous Arithmetics of Distance

#15
post #3

Earlier quoted context omitted.

They are typically not taught in school, at least in the US but probably elsewhere too. I don’t even know of a commonly taken undergrad-level course that I’d expect to cover them.

They're often -- but not always -- touched on in advanced undergraduate classes, e.g. after real analysis and abstract algebra. Not every math undergraduate takes number theory these days.

Which classes are you thinking of?

Re: Marvelous Arithmetics of Distance

#17
> Likewise, if you start with a positive integer that ends in 6 and repeatedly raise it to the fifth power, you converge digit by digit toward the strange number

> b = ···743740081787109376

No you don't. Trying with 6, 16, 26, any number, you don't converge.

Re: Marvelous Arithmetics of Distance

#18
post #17

> Likewise, if you start with a positive integer that ends in 6 and repeatedly raise it to the fifth power, you converge digit by digit toward the strange number > b = ···743740081787109376 No you don't. Trying with 6, 16, 26, any number, you don't converge.

6^5 ends in ...76

6^25 ends in ...376

6^125 ends in ...9376

6^625 ends in ...09376

and so on

Re: Marvelous Arithmetics of Distance

#20
post #4

there must be a rule that bans using “marvelous, magic, mysterious, never seen before, miraculous, genius, shocking …” words used in math posts. There’s nothing marvelous about any of this—it’s just math. Imo it’s better to let people face math head on than try to sugar coat it and click bait them into liking math.

The marvel of Math is in its non-obviousness. Obvious truths are not marvelous but non-obvious ones are. "Magic" is also a word we can use about Math because we know no true magic exists. Therefore when something is said to be "magic" we know it means something "looks like magic". For the Magician (/Mathematician) it of course doesn't look like magic because they clearly understand and see how it works. So, you are p…

> Mathematician/Magician

Or mathemagician. ;-)

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