scientific american - 1994 01 - searching for strange quark matter

... techniqueto search for strange quark matter. The Þrst highly sensitive search for strange quark matter and other parti-cles created in high-energy nuclear col-lisions is now being performed by oneof ... of quarks have yet been observed.MESONSQUARKS ANTIQUARKS BARYONSUP ANTI-UPDOWN ANTI-DOWN STRANGE ANTI- STRANGE u u–d d–s s–K MESON LAMBDAPI MESON NEUTRONNUCLEAR MATTER STRANGE QUARK ... The weak force chang-es the down quarks into up quarks. Aneutron (up quark, down quark, down quark, or udd) can become a proton(up quark, up quark, down quark, oruud) when the weak force changes...

scientific american - 1993 01 - the turbulent birth of the milky way

... 4,650 4,40012-BILLION-YEAR-OLD AGE TRACK15-BILLION-YEAR-OLD AGE TRACKNGC 288NGC 362Copyright 1992 Scientific American, Inc.means that within the halo the only re-maining main-sequence stars ... from hu-mans, pigs, whales and oth-er species. The National En-dowment for the Arts wasnamed as a co-recipient for allegedly encouraging Knowl-ton “to extend his work in theform of a pop-up ... the man.Ó36 SCIENTIFIC AMERICAN January 1993Copyright 1992 Scientific American, Inc.ate summer of 1987 seemed typi-cal for that time of year in theVirgin Islands. Huge, ßat-bot-tomed cumulus...

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scientific american - 1994 02 - do aerosols slow climatic warming

... NationsCopyright 1994 Scientific American, Inc.Such modest nuclear holdings there-fore can suÛce to dissuade an aggres-sor from a nuclear attack. But super-power nuclear forces long ago grew be-yond ... hip lip-shooter find his way through the corridors of power?Laid-Back Leader Rattles the Academy34 SCIENTIFIC AMERICAN February 1994 CHRIS USHER Black StarCopyright 1994 Scientific American, ... an adequate yet afford-able scale for AmericaÕs armed forces,we attempted to answer two basic ques-tions: Who are our most probable ad-38 SCIENTIFIC AMERICAN February 1994 PHILIP MORRISON,...

scientific american - 1994 03 - visiting yourself in the past

... predictions.Copyright 1994 Scientific American, Inc.Copyright 1994 Scientific American, Inc.20 SCIENTIFIC AMERICAN March 1994 In the ÒnaiveÓ quark model, one of thethree quarks spins in a direction oppo-site ... remain on the operating table for awhile. ÑMadhusree MukerjeeCopyright 1994 Scientific American, Inc. SCIENTIFIC AMERICAN March 1994 21membranes surrounding neurons. Pet-tegrew thinks schizophrenics ... AMERICAICELANDHOT-SPOTAREAAZORESHOT-SPOTAREAMID-ATLANTICRIDGECopyright 1994 Scientific American, Inc.conditions in the mantle where thesample rocks formed, because the tem-peratures and...

scientific american - 1994 04 - the dilemmas of prostate cancer

... hisformer critics. Gould, in a review in Na-ture, lauded The Diversity of Life as Òa38 SCIENTIFIC AMERICAN April 1994 Copyright 1994 Scientific American, Inc.Copyright 1994 Scientific American, ... Borneo.36 SCIENTIFIC AMERICAN April 1994 Revisiting Old BattleÞeldsJASON GOLTZCopyright 1994 Scientific American, Inc.Copyright 1994 Scientific American, Inc.gan doing Þeldwork in such exotic lo-cales ... near-death experiences.Alexander is a former U.S. Army col-onel and self-described Òhard-core mer-cenaryÓ with a doctorate in thanatolo-gy, the study of death. In 1980 he wrotean article for...

scientific american - 1994 06 - was there a race to the moon

... Canada. Long-term monitoring is needed to track changes.SARAH LEEN MatrixCopyright 1994 Scientific American, Inc. SCIENTIFIC AMERICAN June 1994 33In 1939 a 33-year-old French mathe-matician ... up-down action oversome unit of time.Schršdinger managed to extract clas- SCIENTIFIC AMERICAN June 1994 45Copyright 1994 Scientific American, Inc.sical behavior from his theory for a har-monic ... stra-tegic management consulting Þrm. SCIENTIFIC AMERICAN June 1994 37Copyright 1994 Scientific American, Inc.McNamara was also intrigued by thepotential military applications of earth-orbiting...

scientific american - 1994 07 - how cancers defeat drug therapy

... of the Þeldwork be-cause many of the men have off-site jobs. SCIENTIFIC AMERICAN July 1994 35Copyright 1994 Scientific American, Inc.years ago. A judicious choice of fast-maturing varieties ... iden-tiÞed by color. All grayish-to-white minerals are feldspar.Tiny orange grains are iron-magnesium minerals.Copyright 1994 Scientific American, Inc.that the giant impact led to the forma-tion ... debrisoriginated from the immense event re-sponsible for the formation of the Imbri-um basin, a 1,300-kilometer-wide dentthat corresponds to the man-in-the-moonÕs right eye. Baldwin also arguedthat...

scientific american - 1994 08 - red tides - a growing hazaed

... ultraviolet obser-vatory still sending streams of new re-sults back to the earth. SCIENTIFIC AMERICAN August 1994 39DEEP-SURVEY TELESCOPE and spectrometers are being pre-pared for integration ... attention to thisproblem for waters such as the PersianGulf, which was free of submarines un-28 SCIENTIFIC AMERICAN August 1994 Attack Submarines for SaleDiesel-powered attack submarines ... oppor-tunity for nations to exploit. The samecan be done for submarines.The market may not be such alarge one for the developed coun-tries to give up. Modern subma-rines cost too much for...

scientific american - 1994 09 - conquering lyme disease

... electroweak. These forces becomeequally strong, joining to form a granduniÞed force. In that case, leptons be-come relatives of the quarks, and sev- SCIENTIFIC AMERICAN September 1994 43CHARACTERS ... budget, way behind SCIENTIFIC AMERICAN September 1994 23Copyright 1994 Scientific American, Inc.schedule and eating into the base pro-gram. I have received hundreds of let-ters from the science ... Laboratory for the Þrst deÞnitive search. A kaonhas one strange quark coupled with anantiup or antidown quark. Alternative-ly, it may have an antistrange quark coupled with an up or down. Kaons be-long...

scientific american - 1994 10 - special issue - life in the universe

... HEAVIER-THAN-AIR FLIGHTTHEORYOFRELATIVITYCOMMUNICATIONSSATELLITETRANSISTORCopyright 1994 Scientific American, Inc.Copyright 1994 Scientific American, Inc. SCIENTIFIC AMERICAN October 1994 ... 0.06GALAXY 3C 330REDSHIFT 0.50DENSITY0.10 .01 RELATIVE ABUNDANCE1.01.010 -2 10 -4 10 -6 10 -8 10 -1 0HELIUMHELIUM 3LITHIUMDEUTERIUMCopyright 1994 Scientific American, Inc.would still be detectable ... GOLTZCopyright 1994 Scientific American, Inc. SCIENTIFIC AMERICAN October 1994 37Mary Leakey waits for my nextquestion, watching from behinda thin curtain of cigar smoke.Leakey is as famous for her...

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