OUR QUANTUM WORLD Wave Molecule duality of Nature

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Yodh. 2. Layout. Iota and its sizeWaves and Particles Waves as particles and Particles as Waves

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OUR QUANTUM WORLD Wave Particle duality of Nature Gaurang Yodh Physics and Astronomy University of California Irvine Yodh

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OUTLINE Atom and its size Waves and Particles Waves as particles and Particles as Waves – Quantum View Milestones of Quantum material science Wave nature of Matter : de Broglie Interference of waves Heisenberg's instability guideline Quantum versus Classical world view Yodh

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How enormous are iotas ? Democritus : Atoms as building pieces. Measure? Shape ? Substance? Width 10 - 7 cm 17000 Copper particles 1 nm = 10 - 9 meters Atomic size decided not till the 19 th century Atoms are little ; around 0.5 nanometers. Nanotechnology manages nuclear controls. Yodh

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Objects VLA Radio Tel KECK Tel eye Optical magnifying lens Techniques of perception http://www.vendian.org/howbig/T Helps you envision sizes Yodh

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Waves and Particles : What do we mean by them? Material Objects: Ball, Car, individual, or point like articles called particles . They can be situated at a space point at a given time. They can be very still, moving or quickening. Falling Ball Ground level Yodh

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Waves and Particles: What do we mean by them ? Basic sorts of waves: Ripples, surf, sea waves, sound waves, radio waves. Need to see peaks and troughs to characterize them. Waves are motions in space and time. Course of travel, speed Up-down motions Wavelength ,recurrence, speed and wavering size characterizes waves Yodh

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Particles and Waves: Basic contrast in conduct When particles impact they can't go through each other ! They can ricochet or they can break Before crash After impact Another after crash state smash Yodh

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Collision of truck with step on top with a Car very still ! Take note of the stepping stool proceed with its Motion forward … .. Likewise the little care front End gets crushed. Yodh

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Head on crash of an auto and truck Collision is inelastic – the little auto is dragged along By the truck… … Yodh

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Waves and Particles Basic contrast: Waves can go through each other ! As they go through each other they can improve or scratch off each other Later they recover their unique shape ! Yodh

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Wavelength Frequency Waves and Particles: Spread in space and time Waves Can be superposed – indicate obstruction impacts Pass through each other Localized in space and time Particles Cannot go through each other - they skip or break. Yodh

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OUR QUANTUM WORLD In the 20 th century, investigation of nuclear frameworks required a crucial amendment of these established thoughts regarding physical items. 1. Light waves displayed molecule like properties – marvels called photograph electric impact in which light impinging on specific metals cause instanteous discharge of electrons in a billiard ball like effect. – the premise of programmed entryway openers in markets 2. Electrons (particles) display wave like properties – they can go through each other ! Wonder of electron impedance – premise of electron magnifying lens Yodh

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OUR QUANTUM WORLD . This quantum photo of the world is inconsistent with our sound judgment perspective of physical articles. We can't particularly characterize what is a molecule and what is a wave !! Neils Bohr and Werner Heisenberg were the draftsmen of this quantum world view, alongside Planck, Einstein, de Broglie, Schrodinger, Pauli and Dirac. Yodh

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TRUE UNDERSTANDING OF NATURE REQUIRED THAT PHYSICAL OBJECTS, WHATEVER THEY ARE, ARE NEITHER EXCLUSIVELY PARTICLES OR WAVES No test can ever quantify both angles in the meantime, so we never observe a blend of molecule and wave. WHEN ONE OBSERVES A PHYSICAL PHENOMENON INVOLVING A PHYSICAL OBJECT, THE Behavior YOU WILL OBSERVE – WHETHER PARTICLE LIKE OR WAVE LIKE – DEPENDS ON YOUR METHOD OF OBSERVATION. THE OBJECT IS DESCRIBED BY MATHEMATICAL FUNCT IONS WHICH ARE MEASURES OF PROBABILITY . Yodh

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MILESTONES OF QUANTUM PHYSICS: J.J.Thomson Established electron as a key molecule of nature. He quantified its charge to mass proportion utilizing a Crooke's tube. Electric current = stream of electrons Animation of electrons moving and being diverted by an electric or attractive field. Crooke's tube: Evacuated tube Visualization of electron bar. Yodh

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Marie Curie and Radioactivity - 1898 Discovered that specific components " suddenly " discharge radiations and change into various components. Just lady researcher to get two Nobel Prizes: One in science and the other in material science. Yodh

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The Quantum of Light or the Photon Particle nature of light was proposed by Einstein in 1905 to clarify the photograph electric impact. Photograph electric impact – programmed entryway openers in markets. Particles of light are called light quanta or photons. Vitality of a Photon = h (recurrence of light) h is a key consistent of nature and it is little in size. Bundle of vitality in photon is small to the point that we don't know about the rain of photons of light impinging on our eyes – pretty much as you can't feel the effect of individual air atoms, you just feel a breeze. Yodh

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Rutherford and his Nuclear Atom: 1898 - 1911 Rr Ernest Rutherford utilized alpha beams to find the core of the molecule. The core was positvely charged and contained the greater part of the mass of the molecule. A large portion of the molecule was unfilled space. Nuclear size Electron cloud Classical material science required that this iota is insecure electrons would fall into the core in 10 - 7 sec! Atomic size Yodh

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Planck and quantization of nuclear " vibrations " Before Einstein, Planck hypothesized from investigation of radiation from hot bodies that the transmitting molecules can just emanate vitality in discrete sums – or that particles exist just in discrete states, called Quantum states. This was the introduction of quantum material science in 1900 Yodh

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THE BOHR ATOM: Bohr proposed a progressive model: A particle with discrete (Quantum) states – a specially appointed model Bohr demonstrate clarified how molecules discharge light quanta and their solidness. He joined the hypothesizes of Planck and Einstein to manufacture trademark vitality expresses that particles ought to have. Show gave great concurrence with analysis on nuclear spectra.(1913 ) Yodh

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Bohr particle Bohr's molecule demonstrate accomplished three critical results: 1. Particles are steady 2. Diverse iotas of a similar component are indistinguishable 3. Iotas recover on the off chance that they are dismantled and afterward permitted to change. Yodh

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THE BOHR ATOM: Understanding the birthplace of Bohr's model required a crucial intense stride – enter Louis de Broglie . Yodh

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Wave nature of material bodies: If light, which traditionally is a wave, can have molecule nature As appeared by Planck and Einstein, Can material particles display wave nature ? Ruler Louis de Broglie while doing his Ph.D. inquire about said particles ought to have wave like properties. Yodh

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Wave Nature of Matter Louis de Broglie in 1923 recommended that matter particles ought to show wave properties pretty much as light waves displayed molecule properties. These waves have little wavelengths as a rule so that their nearness was hard to watch These waves were watched a couple of years after the fact by Davisson and G.P. Thomson with high vitality electrons. These electrons demonstrate an indistinguishable example when scattered from gems from X-beams of comparative wave lengths. Electron magnifying lens photo of a fly Yodh

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A SUMMARY OF DUAL ITY OF NATURE Wave molecule duality of physical protests LIGHT Wave nature - EM wave Particle nature - photons Optical magnifying instrument Interference Convert light to electric current Photo-electric impact PARTICLES Wave nature Particle nature Matter waves - electron magnifying instrument Electric current photon-electron crashes Discrete (Quantum) conditions of kept frameworks, for example, iotas. Yodh

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QUNATUM MECHANICS: ALL PHYSICAL OBJECTS display both PARTICLE AND WAVE LIKE PROPERTIES. THIS WAS THE STARTING POINT OF QUANTUM MECHANICS DEVELOPED INDEPENDENTLY BY WERNER HEISENBERG AND ERWIN SCHRODINGER. Molecule properties of waves: Einstein connection: Energy of photon = h (recurrence of wave). Wave properties of particles: de Broglie connection: wave length = h/(mass times speed) Physical question depicted by a numerical capacity called the wave work . Tests measure the Probability of watching the protest. Yodh

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A limited wave or wave bundle: A moving molecule in quantum hypothesis Spread in position Spread in force Superposition of floods of various wavelengths to make a parcel Narrower the bundle , progressively the spread in energy Basis of Uncertainty Principle Yodh

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ILLUSTRATION OF MEASUREMENT OF ELECTRON POSITION Act of estimation impacts the electron - gives it a kick and it is no more drawn out where it was ! Quintessence of vulnerability rule. Yodh

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Classical world is Deterministic: Knowing the position and speed of all articles at a specific time Future can be anticipated utilizing known laws of drive and Newton's laws of movement. Quantum World is Probabilistic: Impossible to know position and speed with sureness at a given time. Just likelihood of future state can be anticipated utilizing known laws of compel and conditions of quantum mechanics. Entwined Observed Observer Yodh

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BEFORE OBSERVATION IT IS IMPOSSIBLE TO SAY WHETHER AN OBJECT IS A WAVE OR A PARTICLE OR WHETHER IT EXISTS AT ALL !! QUANTUM MECHANICS IS A PROBABILISTIC THEORY OF NATURE UNCERTAINTY RELATIONS OF HEISENBERG ALLOW YOU TO GET AWAY WITH ANYTHING PROVIDED YOU DO IT FAST ENOUGH !! case: Bank worker pulling back money, utilizing it ,however supplanting it before he can be gotten ... Limited PHYSICAL SYSTEMS – AN ATOM – CAN ONLY EXIST IN CERTAIN ALLOWED STATES ... . THEY ARE QUANTIZED Yodh .:

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