This revised edition narrates the brief history of the people, the events, and the ideas that advanced mankind into the electrical, nuclear, and space ages. The book describes the basic concepts of Quantum Mechanics and the efforts made to decipher the secrets of the structure of atoms, molecules, crystals and elementary nuclear particles.The author emphasizes the inherent limitations of classical mechanics that led to paradoxical outcome of the special theory of relativity, which in turn infected Dirac's attempts to rehabilitate the Schrödinger’s Quantum Wave Equations. During the hundred and ten odd years of its existence, Quantum Mechanics has passed through three distinct stages of development. The first stage began by Planck’s quanta and ended de Broglie’s matter waves. It could be properly described as the stage of structuring the electronic shells of the atom. The second stage in the development of Quantum Mechanics began with de Broglie's discovery of matter waves, in 1924 and ended with the end of WWII. It could be properly described as the stage of deciphering the nuclear forces of the atomic core. The theory of the nucleus of the atom was created and new elementary particles were discovered that revealed some of the secrets of the nuclear forces. The third period began after World War II with the invention of nuclear reactors, radiospectrometers, and high altitude flights. This stage could be properly described as the phase of high energy exploration of the nuclear elementary particles. During this stage, Quantum Mechanics come up against ever greater difficulties, setbacks and failures. The newly discovered behaviors of elementary particles and their interactions shook the foundation of the old laws upon which Quantum Mechanics was erected. CHAPTER 1: THE ROAD TO THE ATOM: 1792-1900The Creation from NothingThe Road to ConservationNewton Laws of ConservationBeginning of the Steam AgeThe French RevolutionBirth of ElectricityNobel’s IncentiveLandmarks of the Nineteenth Century Ethereal SpaceLight Spectrum of ElementsDiscovery of the ElectronThomson Model of the AtomDiscovery of X-raysDiscovery of RadioactivityClassical Senses and CannonsBirth of Quantum MechanicsThermal RadiationBlack Body RadiationBoltzmann-Wien LawsRayleigh-Jeans Law CHAPTER 2: THE BIRTH OF THE QUANTAThermal Radiation at High FrequenciesThe QuantaPhotons and CorpusclesDiscovery of PhotonsDual Nature of Light Rutherford Atom ModelBohr Atom ModelPrivileged Atomic Quantum OrbitsEmission and Absorption of RadiationBrightness and Spin of Emitted Radiationde Broglie Matter WavesDual Properties of ElectronsElectron DiffractionQuantum Wave TheoryProbability Wave FunctionUncertainty RelationTunnel EffectSchrödinger EquationHarmonic OscillatorPauli’s Exclusion PrincipleThe SpinElectronic Architecture of the AtomPeriodic Table of ElementsAtomic Spectrum CHAPTER 3: MOLECULES AND SOLIDSMoleculesIonic moleculeCovalent molecules.Quantum Mechanics of SolidsCompound crystalsMetallic crystalsStark EffectMolecular Levels of EnergyInsulatorsConduction in MetalSuperconductivitySemiconductors CHAPTER 4: THE INTERIOR OF THE NUCLEUSRadioactivityThe Nucleus of the AtomThe NeutronNuclear ForcesDiscovery of the MesonNuclear Stability and AbundanceAlpha Particle DecayNuclear Energy LevelsGamma Ray DecayNuclear FissionBeta Particles DecayThe Discovery of the NeutrinoElectron Capture CHAPTER 5: ELEMENTARY NUCLEAR PARTICLESRelativistic Quantum MechanicsDirac’s Quantum Wave EquationsDiscovery of Anti-matterAction at a DistanceField and MatterDecay of Subatomic ParticlesDeduction of Coulomb’s LawClassification of Elementary ParticlesDecay of Elementary Particles CHAPTER 6: CRITIQUE ON QUANTUM MECHANICSCritique on the Special Theory of RelativityCritique on the Theory of Matter Waves CHAPTER 7: CONTRIBUTION BY NATIONS OF SCIENTISTSCHAPTER 8: HIGHLIGHTS OF MAIN FACTS