The materials presented here originated from the research of BLH with Antonio Campos, Nicholas Phillips, Alpan Raval, Albert Roura and Sukanya Sinha, and of EV with Rosario Martin and Albert Roura. We thank them as well as Daniel Arteaga, Andrew Matacz, Tom Shiokawa, and Yuhong Zhang for fruitful collaboration and their cordial friendship since their Ph.D. days. We enjoy lively discussions with our friends and colleagues Esteban Calzetta, Diego Mazzitelli and Juan Pablo Paz, whose work in the early years contributed towards the establishment of this field. We acknowledge useful discussions with Paul Anderson, Larry Ford, Ted Jacobson, Emil Mottola, Renaud Parentani, Raphael Sorkin and Richard Woodard. This work is supported in part by NSF grants PHY06-01550 and PHY05-51164, the MEC Research projects FPA-2004-04582C02 and FPA-2007-66665C02 and by DURSI 2005SGR00082.
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 2.0 Germany License.