E-Book Content
SPECIAL REPORT: FOUR KEYS TO THE COSMOS Making Sense of Microwave Ripples, Gravity Leaks and More FEBRUARY 2004 $4.95 WWW.SCIAM.COM ORGANIC LIGHT EMITTERS ENABLE BETTER ELECTRONIC DISPLAYS THE MYSTERY OF SHOCK WHY DID CRIME RATES FALL? COPYRIGHT 2004 SCIENTIFIC AMERICAN, INC. contents february 2004 SCIENTIFIC AMERICAN Volume 290 Number 2 features BIOTECHNOLOGY 36 Insights into Shock BY DONALD W. LANDRY AND JUAN A. OLIVER For thousands of people every year, a catastrophic drop in blood pressure is the immediate cause of death. Yet shock is becoming more treatable. SPECIAL REPORT 42 Four Keys to Cosmology 44 The Cosmic Symphony BY WAYNE HU AND MARTIN WHITE Sound waves powerfully shaped the early universe. 54 Reading the Blueprints of Creation BY MICHAEL A. STRAUSS New surveys highlight extraordinary cosmic structures. 62 From Slowdown to Speedup 62 Type Ia supernovae shed light on changing rates of cosmic expansion BY ADAM G. RIESS AND MICHAEL S. TURNER Supernovae reveal when the expansion of the universe sped up. 68 Out of the Darkness BY GEORGI DVALI A leakage of gravity might cause cosmic acceleration. INFORMATION TECHNOLOGY 76 Better Displays with Organic Films BY WEBSTER E. HOWARD Light-emitting organic materials can make electronic displays brighter, more efficient—and soon, as thin and flexible as plastic. CRIMINOLOGY 82 The Case of the Unsolved Crime Decline BY RICHARD ROSENFELD Crime rates in the U.S. plummeted in the 1990s. None of the common theories fully explains why, however. www.sciam.com SCIENTIFIC AMERICAN COPYRIGHT 2004 SCIENTIFIC AMERICAN, INC. 3 SCIENTIFIC AMERICAN Volume 290 Num