Monday, October 15, 2007

Cosmic Microwave Background Anomalies

Probing the Origin of the Large-angle CMB Anomalies
There has been mounting evidence that the large-angle cosmic microwave background (CMB) anisotropy has anomalies roughly at 3 sigma level.

Overhang

Overhang
How far over the edge of the table can we reach by stacking n identical, homogeneous, frictionless blocks of length 1? A classical solution achieves an overhang asymptotic to 1/2 ln n. This solution is widely believed to be optimal. We show, however, that it is exponentially far from optimality by constructing simple n-block stacks that achieve an overhang of cn^1/3, for some constant c>0.

With the restriction that only one block can be on top of another, the classical solution is optimal. However with multiple blocks on top of each the solution can be improved significantly.