Physics Tip Sheet #1 - February 20, 2002

Contact: David Harris
harris@aps.org
301-209-3238
American Physical Society

1) Cold anti-hydrogen
Cold antihydrogen atoms might have been made, for the first time, in an experiment at the CERN lab, where positrons and antiprotons are brought together in a bottle made of electric and magnetic fields.

Physics News Update: http://www.aip.org/enews/physnews/2002/split/577-1.html

2) New tests of Einstein theory on space station
Physical Review Letters

Very sensitive tests of Einstein’s Special Relativity can be obtained by conducting experiments with atomic clocks on a space satellite such as the International Space Station (ISS).

Journal: http://link.aps.org/abstract/PRL/v88/e090801

3) Immunization of complex networks
Physical Review E

Complex networks such as the sexual partnership web and the Internet are ideal for the rapid spread of infections. A study shows that random immunization of individuals, even at high proportions, does not necessarily provide global immunity. Therefore, successful immunization strategies must take into account details of how the network is connected.

Journal: http://link.aps.org/abstract/PRE/v65/e036104

4) Increasing the chance of finding a biological target
Physical Review Letters

Some strategies are better than others when a predator is searching for prey, a partner is looking for a mate or a pollinator is seeking a flower.

Journal: http://link.aps.org/abstract/PRL/v88/e097901

5) Marvel Comics universe looks like a real social network
arXiv preprint server

An analysis of 6486 characters from 12,942 comic books reveals a social structure very similar to that found in real life but is very different from the network formed by random association of characters. The properties of real-life networks can be better understood through comparison with artificial networks such as the Marvel network.

Preprint: http://www.arxiv.org/abs/cond-mat/0202174

6) Unusual cosmic ray properties may be explained by supersymmetry
arXiv preprint server

The excess of positrons in cosmic ray measurements cannot be explained by standard particle physics and cosmological models. A new supersymmetric model including light "sneutrinos" and "neutralinos" would explain the data and also mean that these new exotic particles should be observable in the Tevatron and LHC particle colliders.

Preprint: http://www.arxiv.org/abs/hep-ph/0202156

Papers from the Physical Review series of journals are available pre-publication to journalists on request.

For media assistance with these or other physics stories, contact:

David Harris
Head of Media Relations
American Physical Society
Ph: +1 301 209 3238
Fax: +1 301 209 3264
Email: harris@aps.org