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THE NATURE OF MATTER _________________________________________________________ All matter consists of little bits of positive and negative electricity: in perpetual motion; attract each other at short distances; repel each other when pressed too close together. ________________________________________________________ The most important discovery ever made. If all other scientific information we know were lost in some cataclysmic event, and only this information survived, all could be rediscovered in a very short time. - Richard P. Feynman ` ////
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Iron atoms positioned on a carbon surface
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Second Quantization - The Discrete Photon
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700 keV Li + beam (v=4.4 mm/ns) incident on a thin (3 g/cm 2 ) carbon foil. The blue light is H-like 4f-5g in Li 2+ ( 4500Å, =3 ns, x=1.3 cm). The green light is He-like 2s 3 S-2p 3 P in Li + ( 5485Å, =44 ns, x=19 cm).
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Can we picture attractive and repulsive interactions without the force concept? Quantum Field Theory is conceptually easy!
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ACTION-AT-A-DISTANCE Exchange of a ‘gauge boson’ Particle exchange can produce both attraction and repulsion. It is intermittent, like rain on the roof. The Force concept requires an average over a time interval.
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Interactions between any two particles involves all the particles in the universe.
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Position Probability Density Dwell Time
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Why didn’t Isaac Newton think about the possibility of getting hit on the head when he sat under the apple tree? x
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Where does the pendulum spend the most time? The least time?
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Dwell time: High: many / slow Low: Few / fast Time exposure
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Equal time inside No time outside Most time at end points Least time at center Most time at aphelion and perihelion
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Average Values of Powers of the Coordinate
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The secret of life, computers, & transitors
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Laplacian Determinacy – A Costly Mistake Pierre Simon Laplace - 1776: “An intelligence that knows all of the relations of the entities of the universe at one instant could state their positions, motions, and general effects any instant in the past of future. Henri Poincare – 1903: “Small differences in the initial conditions can produce very great ones in the final phenomena – prediction Then becomes impossible (1st recognition of chaos). Werner Heisenberg – 1924: There is a fundamental limit on the accuracy to which position and velocity can be co-determined. Stephen Hawking –1988: In the cosmology of the Big Bang and Black Holes, space and time themselves break down.
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