Atoms and Nature of Science. Mr. Finn Fall, 2013. Richard Feynman.
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AtomsandNature of Science
If, in some cataclysm, all scientific knowledge were destroyed, and only one sentence passed on the the next generation of creatures, what statement would contain the most information in the fewest words? I believe it is the atomic hypothesis(or atomic fact, or whatever you wish to call it) that all things are made of atoms - little particles that move around in perpetual motion, attracting each other when they are a little distance apart, but repelling upon being squeezed into one another. In that one sentence you will see an enormous amount of information about the world, if only just a little imagination and thinking are applied.
Richard Feynman (Nobel Prize, Physics 1965)
Leucipus of Miletus
"The Cheerful Democritus"
Piece of gold:
- cut gold in half repeatedly
- is there a limit to process?
- reach "smallest" piece of gold?
"a-tomos" = un-divided
- pico (p) = 10-12
Scanning electron microscope
Scanning tunneling electron microscope
"By convention sweet is sweet, bitter is bitter, hot is hot, and color is color. But in reality there are only atoms and empty space. That is, the objects of sense are supposed to be real, but it is customary to regard them as such but in truth they are not. Only the atoms and empty space are real."
"All nature then, as it exists by itself, is founded on two things: There are bodies and there is void in which these bodies are placed and through which they move about."
Modern View – All that exists are fields and space-time
nucleus: protons & neutrons
(size ≈ 10-14 to 10-15 m)
electron cloud (quantized orbitals)
1 Å = 10-10 m
"I believe that ideas such as absolute certitude, absolute exactness, final truth, etc. are figments of the imagination which should not be admissible in any field of science. This loosening of thinking seems to me to be the greatest blessing which modern science has given us. For the belief in a single truth and in being the possessor thereof is the root cause of all evil in the world.”
Nobel Prize in Physics (1954)
[Hint: root of physics is "PHYSIS" (ΦΥΣΙΣ) = nature]
“Truth” in science is …
Pour water into top
(apply voltage to atoms)
Infer inner structure …
without directly “seeing” the inside?
Measure water leaving bottom
(spectra of light emitted)