20th Century Science and Invention

E`HPMSPF SPFtPOA¡PQrP E`HP¸PPAnPL

E`HPMSPFSPFtPOA¡PQ``utPO E`HP¸PPA``unPL E`kPPCUF
aAE`HPúPOArP oPF wvPO«PFAHPnPL ePHPM GPLWvPFnPLA

(26)
EnPLwvPOE`ÂFkPPbPLAsPF aAEHPúPOArP

1906 - 11 LçLKPQêPLA¡P
EHP¸PPAnPLQ : aAinPLYãOFWvPF rPAdPLArPifPOAwPOY, hPFAÓOLsLP gPOAvhPFgPOArP,
aAinPLYãOFWvPF mPFAsPFYiwPOnPL

1906 LçLKPQãOFWvPFAi¡P aAinPLYãOFWvPF rPAdPLArPifPOAwPOY ECPFilPnPL kPPAnPLAwPOArP mPFzAkPP²EgPOlP EHPSL÷PEHPdPLzAlPibPL, uyPKPAinPL EtPOEnPL sPFicPFêPL ECPFilPnPL ucPF´È÷PkPP u¾PPiÀeOL` aAlPfPOA kPPNPArP EHPcPFlPnPL pPOLErPmPFApPOL kPPrPitPO F| EtPOEnPL çpPOLtPOz¾PP kPPrPilPnPL, pPOLAtPOlPA a¦ pPOLAitPOrP mPFDPFz EdPLibPL yPAHPArP sPFmPFbPL aAlPfPOA kPPNPA sPFAmPFAnPLz EHPcPFElPtPO hPFbPL usPFAjPLA rPAéPFA uTPikPP F|

vhPFMlPiLÕPLrP mPFzAnPLicPFãOFWvPFAirP rPAdPLArPifPOAwPOY ePHPM hPFAÓOLsLP gPOAvhPFgPOArP gPONPnPLA kPPrPitPO sPF¾PPmPF hPFilPnPL aAlPfPOAkPPNPArP sPFMKPzA, yPKPnPL tPOArPA ePkPPEWvPF EjPLÌPO-sPFAlPfPOAvhPFwPO pPOLdPLYAbPL aAGPLAtPO kPPrPlP F| gPOAvhPFgPOArP oPF aAinPLYãOFWvPF mPFAsPFYiwPOnPL HPzHPhPFArP kPPirPECPFilPnPL ePkPPEWvPF EjPLnPLkPP-sPFAlPfPOAvhPFwPO ãOOfUOLElPËPAbPLnPL gPOnPLkPP-yPÓFíPL (scintillator) EHPEBPOnÔP HPéUFrP ªPArPA aAlPfPOA-kPPNPArP EHPcPFlPnPL EHPXPbPL EnPLDPFYArPNP kPPrPArP jPLnPLz F|

1909 LçLKPQ-rP ugPOAwxPFA uTPikPPvhPF nPLAnPLA tPOTPz sPFMgOÖhPFQtPO kPPrPA hPFlP F| EwPOisPFÈ÷PrP, 1910 LçLKPQ nPLAgPOAdPL rPAdPLArPifPOAwPOY ePvhPF sPFkPPlP tPOTPz HPzAKPzA kPPrPArP jPLnPLz ePkPPEWvPF mPFiwPOlP ûutPOrPQ kPPirP ufPOlPilPnPL F| 1911-LçLKPQrP 7 mPFAcPFY mPFzAnPLicPFãOFWvPFArP %ELitPOrPyPY aÓOdP PEhPFilPAisPFApPOLEhPFcPFlP% usPFAsPFAEbPLEWvPFrP sPFBPOAbPL azAWvPFimPFrP EnPLwvPOE`ÂFkPPbPLArP mPFiwPOlP upPOLSPF kPPrPilPnPL F| aHPSPFz, ujPL.upPOLErPnPL 1901-LçLKPQitPO azAWvPFimPFrP usPF´rP-EsPFiãOFWvPFmPF mPFiwPOlP çpPOLéPFAHP kPPirPECPFilPnPL, rPAdPLArPifPOAiwPOYrP mPFiwPOlP sPFHPYçpPOLTPmPF HPzAKPzA kPPrPitPO pPOLArPilPA aAlPfPOAkPPNPArP EHPi¾PPpPOLnPL pPOLrPQ¾PPA (scattering experiment) uTPikPP lP¢Pì tPOTPzgOUElPrP F|

ePvhPFsPFHP pPOLrPQ¾PPAgOUElP atPOzÙPO gOUrPqñPLFpOLZNPY F| ePrPA azAWvPFimPFrP EnPLwvPOE`ÂFkPPbPLAsPF ePHPM umPF´ElPkPP kPPNPAgOUElPrP EHPXPibPL BPOEHPXPzð pPOLrPQ¾PPA-EnPLErP¾PPArP aAEdPLDPFÿAcPF (prototype) EhPFsPFAiHP kPPAjPL kPPirPiCPF F| rPAdPLArPifPOAiwPOYrP gPOiHPXPNPAbPL pPOLAoPFbPLA ugPOlP EHP©CUFErPtPO aAlPfPOA-kPPNPA EHP©CUFrPNP-ukPPAiNPrP aipPOL¾PPkPP, yPA' uTPikPP çpPOLtPOQbPLmPFAnPL hPFlP uyP azAWvPFmPF aEtPO ¾UædP (tiny), atPOzÙPO GPLnPL (very dense) DPFNPAòPkPP aADPFAinPLrP ukPPArP F|

EcPFÀeOL` : rPAdPLArPifPOAiwPOYrP EnPLwvPOE`ÂFkPPbPLAsPF mPFiwPOlP F

ePWvPFA KLUHPvhPF aAåcPFiyPYrP HPzApPOLArP uyP rPAdPLArPifPOAiwPOYrP mPFiwPOlP çpPOLTPmPF çpPOLTPmPF EHPiSPFXP sPFArPA jPLAgPOAbPLEnPL F| pPOLrPHPtPOYQkPPAilP, nPLQlPsPF uHPArP, 1913 LçLKPQêPLAi¡P HPNPYAlPQ-EHPXPbPLkPP lPAvhPFnPLgOUElP (spectral lines) HPzAKPzArP jPLnPLz rPAdPLArPifPOAiwPOYrP mPFiwPOlP HPzHPhPFArP kPPirPnPL ; mPFAErP kFUOrPQ çpPOLAbPLSPFßvhPF wvPOi`ÂlPKP kPPrPitPOnPL rPAdPLArPifPOAwPOY-mPFiwPOlPikPP tPOÿArP HPÀoÖLÝtPOAbPL ePHPM gPOiHPXPNPApPOLiÀeOL` F|

(27)
apPOLErPHPAEhPFtPOA (Superconductivity)

aAEHPúPOArP : 1911 LçLKPQ
EHP¸PPAnPLQ : hPFAÓOLsLP kPPAimPFrPElPM oPFinPL,
ukPPAimPFElPsPF uwPOAsPFYmPFzAnPL, ugPOErPWvPF vhPFbPLAnPL E`ÂFfPOLmPF oPF gPOAvhPFlPsPF hPFibPLãOFWvPF

1911 LçLKPQêPLAiHPrP 8 ePEçpPOLlP hPFAÓOLsLP kPPAimPFrPElPM oPF tPOÿArP sPFhPFkPPmPFYQrPA aEtPOpPOLErPHPAEhPFtPOA aAEHPúPOArP kPPrPilPnPL F| ePÿrPA udPLKPilPnPL uyP pPOLArPdPL-ePrP urPADPF kPPmPFitPO kPPmPFitPO 'çpPOLAbPL SFZinPLz' upPOL´ÿCPFAbPL yPEdPL tPOArP tPOApPOLmPFAnPL kPPEmPFibPL çpPOLAbPL 3 ukPPlPEBPOnPL kPPrPA yPAbPL F| aAjPL, aEtPOpPOLErPHPAEhPFtPOA EHPdLUzð-uWvPFkPPnPLlPEjPLitPO HPhUF çpPOLibPLAjPLnPL EmPFEWvPFibPLiCPF yPArP mPFiDPFz aAiCPF Magnetic Resonance Imaging (MRI) ePHPM High energy Particle Accelerator F|
kPPAimPFrPElPM EkPPCUF EHPSFUªPì DPFAtUOrP (pPOLArPdPL ePHPM pPOLirP EWvPFnPL oPF sPFQsPFArP) EHPdLUzð- pPOLErPHPAEhPFtPOA pPOLErPmPFApPOL kPPrPECPFilPnPL aEtPO EnPLmÔ`OL tPOApPOLmPFAinPL F| EkPPCUF EHP¸PPAnPLQ, lPwPOY ukPPlPEBPOnPL-sPFhPF, EHPSL÷PAsPF kPPrPitPOnPL uyP pPOLrPmPF SFZnPLztPOAipPOL (Absolute Zero ) pPOLErPHPAhPFQrP mPFDPFz EdPLibPL vhPFilPkPPæWvPFinPLrP gPOEtPO sPFÈOFpOLZNPYBPOhPFiHP rPìªPì hPFibPL yPAiHP F| aTPYAð, pPOLrPmPF SFZnPLztPOAipPOL tPOEwxPFtPOQ urPADPFAÌPO (electrical resistivity) hPFiHP sPFQmPFAhPFQnPL HÖhPFð (infinitely large) F| kPPAimPFrPElPM oPFinPL sPFhPF anPLzAnPLz HP¸PPAnPLQrPA ePvhPF mPFtPO upPOLAXPNP kPPrPitPOnPL uyP, pPOLErPHPAhPFQrP urPADPF tPOApPOLmPFAinPLrP sPFiËP sPFiËP ÀePÝmPFSPFß kPPmPFitPO TPAkPPiHP ePHPM pPOLErPiSPFiXP SFZnPLzmPFAinPL upPOL´ÿCPFAiHP F| agPOAsPFAsPF mPFzAETPwvPO udPLKPAilPnPL uyP tPOApPOLmPFAÀeOL`A kPPmPFArP sPFiËP sPFiËP sPFADPFArPNPtPOß DPFAtUOrP pPOLErPHPAEhPFtPOA HÖEªPì pPOLAbPL ; aTPYAð tPOEwxPFtPOQ urPADPFAÌPO sPFADPFArPNPtPOß kPPimPF tPOApPOLmPFAÀeOL`A kPPmPFArP sPFiËP sPFiËP F|
1911 LçLKPQ-rP 8-vhPF ePEçpPOLlP oPFinPL udPLKPilPnPL uyP 4.2 ukPPlPEBPOnPL tPOApPOLmPFAinPL tPOrPlP EhPFElPbPLAimPF EnPLmPFEµPLtPO ePkPPEWvPF kPPEVPFnPL pPOLArPidPLrP tPOAirPrP urPADPF hPFVPFAð lUâPL hPFibPL ugPOlP F| ePvhPF aAEHPúPOAirPrP mFZlPz HUJPFitPO tPOÿArP udPLrPQ hPFbPLEnPL ( ePWvPFA çpPOLtPOQbPLmPFAnPL hPFibPLiCPF ePkPP SPFtPOA¡PQ pPOLirP tPOÿArP 'unPLAWvPFHPvhPF' uTPikPP ) F| EtPOEnPL ElPiKPiCPFnPL, 'pPOLArPdPL ePkPPEWvPF nFZtPOnPL aHPëPOAbPL upPOL´ÿiCPFiCPF, yPAikPP tPOArP ePvhPF asPFADPFArPNP ûuHPdLUzEtPOkPP DPFimPFYrP jPLnPLz, nPLAmPF udPLoPFbPLA yPAbPL 'apPOLErPHPAhPFQ aHPëPOA' F| pPOLrPHPtPOYQkPPAilP kPPAimPFrPElPMibPLrP EHPEBPOnÔP ulPKPAbPL 'apPOLErPHPAhPFQ' SPF¡PEWvPF HPArP HPArP ePisPFiCPF F|
kPPAimPFrPElPM oPFinPL tPOÿArP ePvhPF EHPiSPFXP kPPAijPLrP ãO÷PQkFÖOEtPO upPOLibPLECPFilPnPL EHPFpOLUlPBPOAiHP ePHPM 1913 LçLKPQ-utPO pPOLdPLATPYEHPdPLzAbPL unPLAiHPlP FpOLUrPúPOArP lPABPO kPPirPnPL 'EnPLmÔ`OL tPOApPOLmPFAinPL pPOLdPLAiTPYrP çpPOLkFÖOEtPOrP wvPOpPOLirP tPOÿArP gPOiHPXPNPArP jPLnPLz, yPArP fPOilP sPFÆPFHP hPFbPL tPOrPlP EhPFElPbPLAmPF wvPOðpPOLAdPLinPL' F|

SPFÌPOrP usPFinPLrP usPF´jPLinPLz L

( cPFlP``uHP )

(aApPOLnPLArP mPFÙPOHPz jPLAnPLA``unPLArP jPL``unPLz EÂFkPPkPP kPPrPqnPL)