P1251328616rwAsp

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What should be the public awareness of Physics?
Is Physics a coherent body of useful contemporary
knowledge? Or
only a Method of Inquiry unchanged since the Age
of Enlightenment?
Intro. Phys. I to American
Revolution Intro. Phys. II to American Civil
War Modern Phys. to the Great Depression
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Relearning the ignorance of the Enlightenment
Planetary motion (Copernicus, Galileo, Brahe,
Kepler 1500-1600)
Newtons laws (Newton 1687)
Electricity (Coulomb 1777)
Magnetism (Oersted 1819)
Line spectra (Kirchhoff 1859)
Kinetic theory (Maxwell 1860)
Relativity EM (Voigt 1887)
Atomic confirmation (Einstein 1905)
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the concept of force has reached the end of its
life cycle (suggesting) its disbarment from the
inventory of fundamental concepts in
physics. Max Jammer, Concepts of Force, 1957
In all methods and systems which involve the
idea of force there is a leaven of artificiality
there is no necessity for the introduction of
the word force nor the sense-suggested ideas
on which it was originally based.
Peter G. Tait,
Dynamics, 1895
If people were to learn to conceive the world in
a new way, without the old notion of force, it
would alter not only their physical imagination,
but probably also their morals and politics.
Bertrand
Russell, The ABC of Relativity, 1925
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Quotes from Force-Trained students
How can a rocket work in outer space where there
is nothing for the force to push on?
The moon doesnt fall to earth because the
centrifugal force holds it out.
If weight is gravitational force, and orbiting
astronauts are weightless, then they must be
outside the range of gravity.
We know that nuclei are small because
?-projectiles miss them and go mainly forward.
If nuclei were large, ?-particles would hit them,
feel a force, and bounce backward.
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Are the problems we assign even realistic?
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Am. J. Phys. 71, 1152 (2003) dispute / R.K.
Adair 73, 184 (2005).
1. Viscous drag nonlinearly couples horizontal
vertical solve numerically.
2. Aerodynamics of backspin dominates the range
achieved.
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A lousy approximation!
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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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(Ohio State Board of Education 12/10/02)
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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 (v4.4 mm/ns) incident on a thin
(3 ?g/cm2) carbon foil. The blue light is
H-like 4f-5g in Li2 (?4500Å, ?3 ns, ?x1.3
cm). The green light is He-like 2s 3S-2p 3P in
Li (?5485Å, ?44 ns, ?x19 cm).
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Can we pictureattractive 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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Nature has revealed a beautiful secret!
The behavior of the Universe becomes very simple
if it is described in a way in which space and
time are symmetric.
What makes it seem hard, is the fact the we must
live our lives by standing at a point in space
and watching time pass, but not the reverse.
Its like our perspective in riding the Earth
around the Sun, which seems as if the Sun were
going around us. However, the heliocentric
equations are much simpler.
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TIME Time is what keeps everything from
happening at once.
- Attributed to John Archibald Wheeler
Quoted by
Woody Allen
Time flies like an arrow fruit flies like a
banana.
- Groucho Marx
Backward turn, turn backward, O time in your
flight. Make me a child again, just for
tonight.
- Elizabeth Akers Allen
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Electron-positron pair production
The photon-dressed electron
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Electron-Positron Pair Creation and Annihilation
Once created, e and e- are stable until
annihilated
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time
Are they all really the same electron?
Future
Here-Now
space
Past
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Why didnt 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
Time exposure
High many / slow
Low Few / fast
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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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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.