
Coin Flip Decides Material’s Fate - mxcrossb
https://physics.aps.org/articles/v13/s81
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mrosett
The connection to the St. Petersburg paradox is pretty tenuous.

All the paper seems to suggest is that strength of a fiber is proportional to
log(length_fiber). But the St. Petersburg paradox doesn't just come from
observing that the odds of getting log_2(n) heads in a row is 1/n. Instead,
you're multiplying that quantity by an exponentially growing quantity and then
taking an expectation (i.e. summing) and getting an unbounded sum. I don't see
a clear analogy to that in material strength.

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msandford
"A chain is only as strong as its weakest link"

And if you model a rope or fiber as multiple chains side-by-side (and on a
molecular level they kinda-sorta are) then the longer the chain the more
likely you end up with multiple parallel/concurrent defects.

It's an interesting finding in that few would ever intuit it but once told
about it they'll say it's "obvious". At least that's what I thought!

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sporkologist
> Materials typically contain lots of small imperfections, but it’s the rare,
> large defects that cause a material to fail.

Ok so.... we need to know more about the rare large defects! Unfortunately
that's the last we hear about them in this paper.

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kangnkodos
So does this mean a space elevator is out?

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bdcravens
For a moment I was excited, and thought Material Design would disappear if it
came up tails.

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ranguna
I was thinking the same thing and was so confused by reading the other
comments hahaha

