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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.
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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 ` ////
700 keV Li+ beam (v=4.4 mm/ns) incident on a thin (3 g/cm2) carbon foil. The blue light is H-like 4f-5g in Li2+ (4500Å, =3 ns, x=1.3 cm). The green light is He-like 2s 3S-2p 3P in Li+ (5485Å, =44 ns, x=19 cm).
Can we pictureattractive and repulsive interactions without the force concept? Quantum Field Theory is conceptually easy!
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.
Interactions between any two particles involves all the particles in the universe.
Position Probability Density Dwell Time
Why didn’t Isaac Newton think about the possibility of getting hit on the head when he sat under the apple tree? x
Where does the pendulum spend the most time? The least time?
Dwell time: Time exposure High: many / slow Low: Few / fast
Equal time inside No time outside Most time at end points Least time at center Most time at aphelion and perihelion
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.