[troutman]

http://physics.harvard.edu/people/fa...ani-hamed.html

Nima Arkani-Hamed’s research in theoretical physics is driven by attempting to address these mysteries. Much of his work has centered around addressing the hierarchy problem. Together with Savas Dimopoulos and Gia Dvali, he suggested that the extreme weakness of gravity can be attributed to the existence of large extra dimensions of space, perhaps as large as 100 microns in size, with the scale of quantum gravity lowered to the electroweak scale. This opens up the possibility that quantum gravitational effects can be probed at accelerators and even in table-top experiments. In a different direction, together with Andy Cohen and Howard Georgi he has constructed models where (non-gravitational) extra dimensions are generated dynamically from purely four-dimensional models. This has also led to new approaches to the hierarchy problem. He has also investigated the possibility that gravity is modified at large distances and times in an effort to address various cosmological problems. Most recently, together with Dimopoulos, he has explored the possibility that the fine-tunings for the cosmological constant and hierarchy problems find a common explanation within a huge landscape of possible low-energy worlds that may exist in string theory, leading to a novel proposal for "split" supersymmetry at the large hadron collider.