Dreyfus, Flin, Franceschi: Degenerate systems of three Brownian particles with asymmetric... https://t.co/wuxEWeLwIU https://t.co/d3HCS7dgOO https://t.co/r5s7SlPa0Q
Deux vies fauchées, une douleur immense.
Mon amie, son père. Partis trop tôt.
Une cagnotte a été lancée pour leurs obsèques et pour soutenir ceux qui restent, ceux qui doivent continuer malgré tout.
Chaque geste compte. Merci du fond du cœur.
https://t.co/duLUo8rXMw
Major breakthrough on arxiv today:
https://t.co/HLm28YnkrF
Ben Green and Mehtaab Sawhney push “Type II sum” techniques using Gowers norms, quantitative “concatenation” theorems, and the “quasi polynomial inverse theorem” to settle whole classes of major open problems about whole numbers! Their formulation is that, as p and q range over the primes, the expression p^2 + (2q)^2 is itself also prime infinitely often. (You can generalize it to p^2+n q^2 where n=0 or 4 mod 6). Mehtaab gave a beautiful lecture on this here at Princeton a few weeks ago.
I prefer the following formulation in terms of Pythagorean triples: as (x,y,z) ranges over primitive solutions to
x^2+y^2=z^2,
there are infinitely many (in fact, a Zariski dense set) for which
xyz/60
is the product of 5 prime factors! (That’s least possible, if you insist on Zariski density. The related problem for “area”, that is, xy/2, is discussed in my survey: https://t.co/Xcr0lZQbkK) After the classical parametrization
x=u^2-v^2, y=2uv and z=u^2+v^2,
with u and v of opposite parity, this amounts to the study of prime factors of:
uv(u-v)(u+v)(u^2+v^2).
So clearly you’ll generically have 5 prime factors. Basically, they can do one binary quadratic plus any number of linear terms. Amazing!!!
Rare et rassurant que des ingénieurs des grandes écoles s'engagent publiquement. Dans l'Huma, ils appellent simplement à la raison, notamment sur les enjeux écologiques & sociaux, qu'un seul programme prend au sérieux. Comme eux, votez & faites voter NFP !
https://t.co/RM2StaMFGX
(9/9) Of course these beautiful simulations are the result of some beautiful maths, and it is easy to create probabilist variations of the sandpile model. Someday I'd like to take some time to study those generalizations.
(1/9) Today, I'm playing with abelian sandpile⌛️, a simple process that creates beautiful patterns. Every figure in this thread is produced by my own (sub-optimized) @Scilab code.
This better become the top election issue. https://t.co/b1VryF2AVB
Sign the petition and say yes to mathematically complicated footballs! https://t.co/SoEVpLjMEA
Reflected Brownian Motion in a wedge: sum-of-exponential absorption probability at the vertex and differential properties - Archive ouverte HAL https://t.co/wL4wW8k9Wk