scientific american - 2000 04 - quantum teleportation

... satel- lite —one of a fleet called the Earth Ob- serving System — uses five state-of- the-art sensors to better diagnose the planet’s health from the sky. 98 92 Copyright 2000 Scientific American, ... Tower A virtual-reality control tower helps to test new runway designs and traffic patterns Copyright 2000 Scientific American, Inc. By the Numbers30 Scientific American April 2000 al...

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... (212) 35 5-0 408. Index of articles since 1948 available in electronic format. Write SciDex™, SCI- ENTIFIC AMERICAN, 415 Madison Ave- nue, New York, N.Y. 1001 7-1 111, or fax (212) 35 5-0 408. Photocopying ... as patchy as the calico cat herself. ÑJohn Rennie 30 SCIENTIFIC AMERICAN April 1993 Copyright 1993 Scientific American, Inc. 32 SCIENTIFIC AMERICAN April 1993 I f atom...

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... charge-density wave or a spin-antiparallel (or “singlet”) superconducting state results. CHARGE-DENSITY WAVE SPIN-DENSITY WAVE SPIN-UP ELECTRON HOLE SPIN-DOWN ELECTRON Copyright 1994 Scientific American, ... in re- SCIENTIFIC AMERICAN April 1994 53 CHARGE AND SPIN DENSITIES of electrons are shown in nor- mal metals, charge-density waves and spin-density waves. The spin-up (orange ) and...

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... ÑSasha Nemecek 26 SCIENTIFIC AMERICAN April 1995 U ntil recently, many medical in- vestigators believed the AIDS vi- rus remains more or less dor- mant in asymptomatic persons, step- ping up its ... But from the moment I walk into the direc- torÕs modest oÛce, it is appar- ent that its newest inhabitant, Arati Prabhakar (pronounced AR-ah-thee Pra-BOCK-er), does not Þt the archetype for th...

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... (212) 98 0-8 175 or call (800) 77 7-0 444. Scientific American- branded products avail- able. For free catalogue, write Scientific Ameri- can Selections, P.O. Box 11314, Des Moines, IA 5034 0-1 314, or ... trapped in amber yield 25-million-year-old DNA Copyright 1996 Scientific American, Inc. L ast October a jury in Reno, Nev., ordered Dow Chemical Com- pany to pay Charlotte and Mar...

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... 29 Copyright 1997 Scientific American, Inc. I t has been said that “Internet secu- rity” is an oxymoron. Privacy, ac- countability and restricted infor- mation, the argument goes, are techno- logically ... a cer- tain profile was made for lo- gistical reasons. The need to pick out un- matched bags from an air- plane cargo hold might cre- ate significant delays within the U.S. system of hub a...

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... the competing cable-modem Internet ser- vice, offered in the same area by Cox Communications. U S West is also offer- ing higher-speed ADSL services aimed at businesses; a 70 4- kilobit-per-second connection ... Now, as Tama- gotchis, the most famous brand of virtual pet, become the rage for girls, the lessons are shifting. “The transition is from objects-to-think-with to objects-to-nurture,”...

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... New Eye Opens on the Cos- mos,” on page 104] . Subaru, the Japa- nese word for the Pleiades star cluster, boasts the planet’s largest single-piece mir- ror, an 8.3-meter-diam- eter wonder (others ... giant light-col- lecting machines in- clude another Mauna Kea resident, the Gemini North Obser- vatory, backed by the U.S. and six other na- tions, which is near- ing its own first-light images...

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... and its technol- ogy last July, the FAA gathered 24 ADS- B-equipped aircraft of various sizes (everything from a Boeing 757 and sev- eral 727s to a navy P-3 Orion and a sin- gle-engine Piper ... passenger-vehicle drivers are at fault in 70 percent of fatal crashes involving heavy trucks.In the most com- mon type —head- on collisions — passenger-vehi- cle drivers crossed the cen- ter line ......

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... comfort of a well-es- tablished brand-name. —Paul Wallich News and Analysis 38 Scientific American February 2000 CYBER VIEW Your First $20 Free! DAVID SUTER Copyright 2000 Scientific American, Inc. The ... painstakingly sepa- rated thousands of salt-grain-size for- ams from their muddy mass grave us- ing a tiny paintbrush. Her search re- vealed that 55 percent of the species of deep-...

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