About the Authors

Avraham Ben-Aroya

student

Tel-Aviv University

Tel-Aviv, Israel

abrhambe[ta]tau[td]ac[td]il

http://www.cs.tau.ac.il/~abrhambe

student

Tel-Aviv University

Tel-Aviv, Israel

abrhambe[ta]tau[td]ac[td]il

http://www.cs.tau.ac.il/~abrhambe

**Avraham Ben-Aroya**is a graduate student at Tel-Aviv University. His advisors are Oded Regev and Amnon Ta-Shma. His research interests include quantum computation, pseudorandomness and other topics in theoretical computer science. He also enjoys playing tennis, chess and plastic guitars.

Oded Schwartz

postdoc

Institut für Mathematik, MA 4-5,

Technische Universität Berlin

10623 Berlin, Germany

odedsc[ta]math[td]tu-berlin[td]de

http://www.math.tu-berlin.de/numerik/mt/schwartz_de.html

postdoc

Institut für Mathematik, MA 4-5,

Technische Universität Berlin

10623 Berlin, Germany

odedsc[ta]math[td]tu-berlin[td]de

http://www.math.tu-berlin.de/numerik/mt/schwartz_de.html

**Oded Schwartz**completed his Ph.D. at Tel-Aviv University in 2007; his advisors were Muli Safra and Amnon Ta-Shma. This is his first paper in Theory of Computing.

Amnon Ta-Shma

professor

Tel-Aviv University

Tel-Aviv, Israel

amnon[ta]tau[td]ac[td]il

http://www.cs.tau.ac.il/~amnon

professor

Tel-Aviv University

Tel-Aviv, Israel

amnon[ta]tau[td]ac[td]il

http://www.cs.tau.ac.il/~amnon

**Amnon Ta-Shma**is a theoretical computer scientist. This is his second paper in Theory of Computing.