Motivated by the question of when the characteristic polynomial of a matroid factorizes, we study join-factorizations of broken circuit complexes and rooted complexes (a more general class of complexes). Such factorizations of complexes induce factorizations not only of the characteristic polynomial but also of the Orlik-Solomon algebra of the matroid. The broken circuit complex of a matroid fa...

during fixation of a femoral neck fracture in a 23-year-old male patient with cannulated screws, a broken guide wire fragment inadvertently advanced through the hip joint and protruded into the pelvis. a second surgical approach was needed to remove the broken fragment from the pelvis. awareness of such a potentially devastating complication will make surgeons more cautious during implementatio...

We review some approaches to macroscopic irreversibility from reversible microscopic dynamics, introducing the contribution of time dependent perturbations within the framework of recent developments in non-equilibrium statistical physics. We show that situations commonly assumed to violate the time reversal symmetry (presence of magnetic fields, rotating reference frames, and some time depende...