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1、IntrotoQuantumMechanics Thispageisintendedtogiveabriefoverviewoftheimportanceandwonderofquantummechanics.Unfortunately,mostpeoplebelieveyouneedthemindofEinsteininordertounderstandQMsotheygiveuponitentirely.(Interestingsidenote:Einsteindidn'tbelieveQMwasacorrecttheo
2、ry!) Iftheabovepictureisyourideaofanatom,withelectronsloopingaroundthenucleus,youareabout70yearsoutofdate.It'stimetoopenyoureyestothemodernworldofquantummechanics!Thepicturebelowshowssomeplotsofwhereyouwouldmostlikelyfindanelectroninahydrogenatom(thenucleusisatthec
3、enterofeachplot).Whatisquantummechanics?Simplyput,quantummechanicsisthestudyofmatterandradiationatanatomiclevel.Whywasquantummechanicsdeveloped?Intheearly20thcenturysomeexperimentsproducedresultswhichcouldnotbeexplainedbyclassicalphysics(thesciencedevelopedbyGalileoGal
4、ilei,IsaacNewton,etc.).Forinstance,itwaswellknownthatelectronsorbitedthenucleusofanatom.However,iftheydidsoinamannerwhichresembledtheplanetsorbitingthesun,classicalphysicspredictedthattheelectronswouldspiralinandcrashintothenucleuswithinafractionofasecond.Obviouslythat
5、doesn'thappen,orlifeasweknowitwouldnotexist.(Chemistrydependsupontheinteractionoftheelectronsinatoms,andlifedependsuponchemistry).Thatincorrectprediction,alongwithsomeotherexperimentsthatclassicalphysicscouldnotexplain,showedscientiststhatsomethingnewwasneededtoexplain
6、scienceattheatomiclevel.Ifclassicalphysicsiswrong,whydowestilluseit?Classicalphysicsisaflawedtheory,butitisonlydramaticallyflawedwhendealingwiththeverysmall(atomicsize,wherequantummechanicsisused)ortheveryfast(nearthespeedoflight,whererelativitytakesover).Foreverydayth
7、ings,whicharemuchlargerthanatomsandmuchslowerthanthespeedoflight,classicalphysicsdoesanexcellentjob.Plus,itismucheasiertousethaneitherquantummechanicsorrelativity(eachofwhichrequireanextensiveamountofmath).Whatistheimportanceofquantummechanics?Thefollowingareamongthemo
8、stimportantthingswhichquantummechanicscandescribewhileclassicalphysicscannot:·Discretenessofenergy·Thewave-particledu
