Three string theorists added as Dirac Medal winners
On August 8th of every year, the Abdus Salam Institute in Trieste, Italy chooses up to three recipients of the Dirac Medal. (It's the anniversary of Dirac's 1902 birth. There exist three other awards called the "Dirac Medal" which I will ignore because they're less relevant for this blog's audience.)
Of course, the medal tries to decorate deep minds who are doing a similar kind of profound research as Paul Dirac did which is why dozens of string theorists have already won it. The Dirac Medal shows what the Nobel prize would look like if the committee weren't constrained by the required explicit, dynamite-like demonstration of the physical discoveries.
In 2014, i.e. two weeks ago, the Italian institute avoided all experiments and awarded just three string theorists:
Ashoke Sen, Andrew Strominger, Gabriele VenezianoCongratulations! Of course, Veneziano is the forefather of the whole discipline (the intercourse that has led to the birth was Veneziano's encounter with the Euler Beta function), Andy Strominger is a lot of fun and a perfectly balanced top thinker in one package and I know him the best of all, of course ;-), and Ashoke Sen is among the most brilliant minds, too. He has previously won the Milner award, too.
The Hindu printed a short yet interesting interview with Ashoke Sen yesterday:
It's true that the Hawking radiation of a "larger than minimal" black hole has a higher number of decay products (particles) so it's more uniform but for the truly minimum-size black holes, there's no difference.
String theory makes this unification of particles and black holes very explicit and elegant and Ashoke Sen has contributed to these wonderful insights a lot. String theory generally predicts an infinite spectrum of particle species – the perturbative "Hagedorn" tower of excited string states is the first glimpse of it, and it gets transformed to black hole microstates for even higher masses where the spectrum gets even denser.
Or you may go in the opposite direction: as a black hole is shrinking, the quantum effects and effects that may be represented as the quantization of its mass eigenvalues get increasingly important and once you get to the sub-Planckian masses, there are just a few black hole microstates and they are identical to the known elementary particles.
The interview mentions his work on S-duality and his research of the black hole microstates. Ashoke was also the #1 soul behind the tachyon minirevolution in the late 1990s but he remained modestly silent about it.
He is also asked about the criticisms directed against string theory that we may still occasionally hear. He reminds everyone of the fact that not just string theory but any theory claiming to clarify the quantum foundations of gravity deals with new phenomena at (at least superficially) experimentally inaccessible scales – the Planck length has been known and known to be ultratiny for more than 100 years (Planck defined the natural units in 1899). So we have two options: either to hang ourselves, or to try to get as deeply as we can with the available knowledge and tools.
String theory is choosing the second option, Ashoke states. Those who are not choosing the second option should at least follow the first option more rigorously so that we don't hear so much unnecessary yelling before they complete their alternative, non-stringy strategy.