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emileokada

Re:Yellow vests knock out 60% of all speed cameras in France on Friday January 11, 2019 @06:39AM (#18882763)
If I recall correctly, they are now also only allowed to be placed where road accidents have happened before.
Re:Which mathematical definitions should be formalised in Lean? on Sunday September 23, 2018 @02:50AM (#18049760)
I thought this mathoverflow post might be of interest to those who mentioned automated theorem proving in discussions on the recent post on the ABC conjecture (https://news.ycombinator.com/item?id=18034714).
I believe the article explicitly steers away from this because nearly all the discourse on this proof has been precisely about this (c.f. remark Scholze that 'The whole discussion surrounding the proof had gotten “too sociological,”').
A lot of proofs at masters level and beyond omit a lot of details because they can easily be checked, but would be tedious to write out explicitly. This means that a 1 page proof would probably actually correspond to 2-3 pages (or more!) if written out with all the details (e.g. with standard but tedious arguments fleshed out properly, and all cases delt with explicitly (rather than resorting to a 'and the other cases follow through similarly' remark)). When written in a proof assistant this would become even longer because natural language allows us to brush a lot details under the carpet because they are understood from context.
Re:Deep image reconstruction from human brain activity (2017) on Wednesday September 12, 2018 @07:30AM (#17967401)
Not convinced this is as junk as you claim it to be. From the abstract:

> While our model was solely trained with natural images, our method successfully generalized the reconstruction to artificial shapes, indicating that our model indeed reconstructs or generates images from brain activity, not simply matches to exemplars.

If I am reading that correctly it is reconstructing images that the subjects had not seen before.

Re:1/0 = 0 on Friday August 10, 2018 @05:18PM (#17736816)
It's quite staggering how many people have posted on this thread without reading the article. Nearly all the objections people have raised are directly addressed in the post.

For those who still object to the argument, would you object to me defining the piecewise function f:R->R defined to be 1/x for x =/= 0 and 0 for when x=0?

Re:1/0 = 0 on Friday August 10, 2018 @05:15PM (#17736799)
This is not true if you say division by 0 is undefined or +inf either. It really is totally fine.
Re:1/0 = 0 on Friday August 10, 2018 @05:11PM (#17736769)
> However, it is definitely possible to define some operation such that 1 `op` 0 := 0, just not the inverse operation of multiplication.

If you read the post this is actually exactly what the OP is saying.

Re:Mathematicians Find Wrinkle in Famed Fluid Equations on Friday December 22, 2017 @03:20AM (#15986012)
I'm not sure what you're getting at. Classically we expect that given the same initial conditions, the outcome of a fluids experiment should always be the same. If an equation meant to describe fluid flows doesn't have this property, it is probably a bad model.
Re:Mathematicians Find Wrinkle in Famed Fluid Equations on Friday December 22, 2017 @02:17AM (#15985795)
No. They've shown non-uniqueness of solutions of a strictly weaker problem. They have yet to say anything about the actual Navier-Stokes problem.