Instability of Anti-de Sitter Space-Time

A recent article in the QuantaMagazine (link) discusses a paper of Georgios Moschidis (arXiv:1812.04268) who proved instability of Anti-de Sitter space-time for a certain Einstein-matter system. Recall that the Anti-de Sitter space-time is the maximally symmetric solution of the vacuum Einstein equations in the presence of a negative cosmological constant. One can attach a boundary-at-infinity to Anti-de Sitter … Continue reading "Instability of Anti-de Sitter Space-Time"

Reports on Impact of Mathematics

A week ago the EMS posted links to reports on the impact of mathematical research on society and economy. You can access these reports here: link. Though probably for many too long to read in detail, reading just the introductions is already interesting.

Multiplying integers

The classical algorithm, that everyone knows from elementary school, for multiplying two n-digit integers runs in $$O(n^2)$$-time. Recently, there was a preprint posted on HAL (link) in which the authors provide an algorithm which runs in $$O(n\log(n))$$-time. A nice article about this discovery may be found at the QuantaMagazine: link. Further, it was also recently proven in another preprint … Continue reading "Multiplying integers"

Strong cosmic censorship conjecture

The cosmic censorship conjectures concern the singularities arising in general relativity. In May the QuantaMagazine published an article (link) about a potential disproof of a strong version of the cosmic censorship conjecture. This article is nicely written and I recommend everybody interested in general relativity reading it. The preprint the QuantaMagazine refers to is arXiv:1710.01722 … Continue reading "Strong cosmic censorship conjecture"

Mathematik in der Blütezeit des Islam

Die Wikipedia veranstaltet jährlich einen Schreibwettbewerb (link). Es gibt jeweils einen Jurypreis und einen Publikumspreis, und dieses Jahr ging der Publikumspreis an einen mathematischen Artikel: Mathematik in der Blütezeit des Islam. Ein paar mehr Infos gibt es auch in diesem ScienceBlog: link.

Snowflakes at infinity

The countless shapes of snowflakes have long raised the curiosity of many scientists, among others the famous Kepler. They have by now been classified by empirical observation into 80 different shapes, but a mathematical explanation for this classification seems to be missing. A striking point about them is that, even though two snowflakes are almost … Continue reading "Snowflakes at infinity"

S-matrices and the big unification

A week ago, the long-awaited preprint Scattering Forms and the Positive Geometry of Kinematics, Color and the Worldsheet by Arkani-Hamed, Bai, He, and Yan, appeared on the ArXiv. Michael Rios and David Chester in two videos try to explain the essence of the new work and, for example, the compatibility with Garrett Lise’s E8 theory. … Continue reading "S-matrices and the big unification"

Gauß in Regensburg

The German Mathematical Society (DMV) offers twice a year the „Gauß Lecture“, an overview lecture with a well-known mathematician. The lecture is intended to show current developments in mathematics and addresses the interested public. At this link is the chronicle of previous lectures. The last of this years lectures has been given by Cédric Villani at … Continue reading "Gauß in Regensburg"

What in the world is topological quantum matter?

Always wondered what the work of the 2016 Nobel prize laureates might have to do with topology? This recent video from Fan Zhang may give a first idea: