Or maybe it really has?
Well, it’s just a pre-print, not yet peer-reviewed or published, so the sensible money’s got to be firmly on “not” for the time being.
The Developer On Line blog has an interesting post pointing out that the university responsible does have some form in this regard.
The story is that in 2004, Louis de Branges released a “proof” (and an accompanying expository apology [pdf]), which was met with near universal eyebrow-raising. Among the skeptics was Xian-Jin Li, his former PhD student, who indeed had previously coauthored a paper containing counterexamples to De Branges’ approach.
Now Li is claiming his own proof. How much it’s based on De Branges’ I couldn’t say (but he doesn’t get a reference).
Anyone who claims to have proved the Riemann Hypothesis is gambling with their reputation, and of course such claims are ten a penny. But it should be noted that these folks are[1] serious mathematicians, and not total cranks.
UPDATE: Terry Tao and Alain Connes both say “no”. Ok, Li’s apparently “updated” the paper since, but…
False alarm folks. Maybe next time he might think to ask some experts to check the paper before going public?