
Random walkers illuminate a math problem - bryanrasmussen
https://physicstoday.scitation.org/do/10.1063/PT.6.1.20190808a/full/
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subroutine
Tangentially related, I recently searched for an equation that could provide
the expected mean particle displacement (at some dt) given the average
particle diffusion rate. I was surprised to find out who solved this
problem... Brownian motion was first described in 1827 by botanist Robert
Brown while looking through a microscope at pollen immersed in water, which
seemed to move with a so-called 'random walk'. Around 80 years later, the
young physicist Albert Einstein published his first relatively (heh) important
contribution to science - an article that worked out the math describing this
stochastic motion. Here's the paper:

[http://www.maths.usyd.edu.au/u/UG/SM/MATH3075/r/Einstein_190...](http://www.maths.usyd.edu.au/u/UG/SM/MATH3075/r/Einstein_1905.pdf)

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heavenlyblue
I don't think that the author of the article has any idea what they are
speaking about.

Retelling the article:

    
    
      - I am speaking about a result Z.
      - Here's the proof for A (obvious)
      - Here's the proof for B (obvious)
      - Here's the proof for C (obvious)
      - This is a great achievement.
    

I did not read the original paper, but am I missing something from the article
itself?

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andrewflnr
I rather suspect the opposite problem: the author has too much math background
to realize when they're using too much lingo and skipping too many steps. That
or they're really just copy-pasting from someone like that. Anyway, the
article did make sense eventually, mostly, after I read it three times.

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heavenlyblue
So who are those PR releases are targetting?

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andrewflnr
Good question. I didn't say it was a smart way to write.

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acd
How does this relate to stock trading? There is a book A random walk down Wall
Street on random walks related to trading.

[https://en.m.wikipedia.org/wiki/A_Random_Walk_Down_Wall_Stre...](https://en.m.wikipedia.org/wiki/A_Random_Walk_Down_Wall_Street)

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lordnacho
So what happens if you attempt to do proof by induction? I guess you get stuck
proving that the general n+1 case equals pi/2?

I certainly expect so.

