The slides from my May class on the 10 (+1) most beautiful experiments in Physics. http://brooklynbrainery.com/courses/66-physics-experiments

1. The correct analogy for the mind is not a vessel that needs filling, but wood that needs igniting - no more - and then it motivates one towards originality and instills the desire for truth. Suppose someone were to go and ask his neighbors for fire and find a substantial blaze there, and just stay there continually warming himself: that is no different from someone who goes to someone else to get to some of his rationality, and fails to realize that he ought to ignite his own flame, his own intellect, but is happy to sit entranced by the lecture, and the words trigger only associative thinking and bring, as it were, only a flush to his cheeks and a glow to his limbs; but he has not dispelled or dispersed, in the warm light of philosophy, the internal dank gloom of his mind.- Plutarch

2. Eratosthenes of Cyrene, 194 BC Jean-Bernard-Léon Foucault , 1851 Galileo Galilei, 1600s Galileo Galilei, 1600s Henry Cavendish, 1781 Albert Michelson, 1887 Isaac Newton, 1671 Thomas Young, 1803 Robert Millikan, 1909 Ernest Rutherford, 1911 Claus Jönsson, 1961

3. What is Beauty?

4. The most beautiful thing we can experience is the mysterious. It is the source of all true art and all science. (S)He to whom this emotion is a stranger, who can no longer pause to wonder and stand rapt in awe, is as good as dead: his eyes are closed. - Albert Einstein

5. Symmetric and proportional is pretty.

6. James Franco is perfect.

7. Nature likes symmetry and nice ratios.

8. Art, too.

9. The beauty of symmetry

10. Finding a deeper reality.

11. Math #winning

15. Experiment Theory Normal Science versus Paradigm Changing Science. Life moves in fits and starts.

16. How big is the Earth?

17. β Eratosthenes of Cyrene, Born 276 BC, Died 194 BC 3rd Librarian of Alexandria Not the first person to guess the world was round. Just proved it, nicely.

18. The Facts

19. 7 The interpretation

20. #mathforthewin

21. Does the Earth Move?

22. There’s a difference between this…

23. And this…

24. Inertial frames of reference.

25. So, the earth still must stand still, right?

26. The model only goes so far…until the facts and the theory don’t line up any more.

27. Fudging it.

28. It gets messy.

29. De revolutionibusorbiumcoelestium in 1543 cleaned things up.

30. Not everyone agreed. Tycho Brahe kept the earth still.

31. An object in motion tends to stay in motion F=ma For every action there is an equal and opposite reaction Newton’s Laws

32. F=ma F=0 a=0 Some #mathforthewin

33. 10 An object in motion, with no external forces on it…moving.

34. How it’s hung.

35. The building moves. http://www.calacademy.org/products/pendulum/

36. Vindication! South Pole, 2001 http://www.phys-astro.sonoma.edu/graduates/baker/southpolefoucault.html

37. Gravity Part one: Do heavy and light objects fall at the same rate?

38. Gravity Part two: How fast do objects fall?

39. Science didn’t exist in 1564.

40. http://einstein.stanford.edu/SPACETIME/spacetime3.html Leaning tower Galileo Inclined Plane By Galileo’s Death in 1642, the book of nature was being “written in the language of mathematics”

41. Fucking Aristotle.

42. 2 Never happened? But an elegant solution.

43. 8 Simple equipment for a deep problem.

44. Seeing is believing.

45. http://www.vias.org/physics/bk1_05_01.html Thought experiments!

46. Giambattista Benedetti Demonstratio proportionum motuum localium (1554) Galileo Galilei DeMotu (1590) Not the first.

47. SIMPLICIO: There can be no doubt but that a particular body . . . has a fixed velocity which is determined by nature. . . SALVIATI: If then we take two bodies whose natural speeds are different, it is clear that, [according to Aristotle], on uniting the two, the more rapid one will be partly held back by the slower, and the slower will be somewhat hastened by the swifter. Do you not agree with me in this opinion? SIMPLICIO: You are unquestionably right. SALVIATI: But if this is true, and if a large stone moves with a speed of, say, eight [unspecified units] while a smaller moves with a speed of four, then when they are united, the system will move with a speed less than eight; but the two stones when tied together make a stone larger than that which before moved with a speed of eight. Hence the heavier body moves with less speed than the lighter; an effect which is contrary to your supposition. Thus you see how, from your assumption that the heavier body moves more rapidly than the lighter one, I infer that the heavier body moves more slowly.

48. A special case.

49. Measuring time.

50. http://comenius.liceodavincitn.it/comenius/comenius/inglese/inclinato1ing.html Taking some measurements

51. http://comenius.liceodavincitn.it/comenius/comenius/inglese/inclinato1ing.html Doing some math. F*@% you Aristotle.

52. http://www.sciencemuseum.org.uk/images/I060/10326303.aspx Making nothing since 1659.

53. “This new vacuum had better placement of the pumps valves and a preferable method of cranking its piston and supporting the air pump's cylinder. Boyle also proved for the first time that all objects, no matter how light or heavy, fall through a vacuum at the same speed. This showed, as Galileo had predicted, that the force of gravity is uniform. In another experiment, Boyle demonstrated that the sound of a clock ticking could not be heard in a vacuum, proving that sound waves depend on air for their transmission. Boyle showed, however, that electrical attraction could be felt through a vacuum.” Boyle and Hooke

54. A better setting for experimentation.

55. Gravity Part three: What is the force of attraction between two bodies?

56. As above, so below.

57. If I have seen so far, it is because I have stood on the shoulders of giants.

58. The inverse square law is actually common sense

59. Energy diffused over a larger and larger area

60. 6 Two 350 lb lead spheres, a rod and some wire.

61. Known masses and forces gives G

62. G gives the mass of the Earth.

63. Since we know the force of terrestrial gravity, for any given mass.

64. What is light made of: Part One

65. Fucking Aristotle.

66. Newton Cared…about telescopes.

67. 4 Glass bends light and produces chromatic aberration. Better knowledge of light=better telescopes.

68. http://www.departments.bucknell.edu/history/carnegie/newton/refraction.html “light consists of rays differently refrangible”

69. A Letter of Mr. Isaac Newton ... containing his New Theory about Light and Colors Philosophical Transactions of the Royal Society, No. 80 (19 Feb. 1671/2) The gradual removal of these suspitions, at length led me to the ExperimentumCrucis, which was this: I took two boards, and placed one of them close behind the Prisme at the window, so that the light might pass through a small hole, made in it for the purpose, and fall on the other board, which I placed at about 12 feet distance, having first made a small hole in it also, for some of that Incident light to pass through. Then I placed another Prisme behind this second board, so that the light, trajected through both the boards, might pass through that also, and be again refracted before it arrived at the wall. This done, I took the first Prisme in my hand, and turned it to and fro slowly about its Axis, so much as to make the several parts of the Image, cast on the second board, successively pass through the hole in it, that I might observe to what places on the wall the second Prisme would refract them. And I saw by the variation of those places, that the light, tending to that end of the Image, towards which the refraction of the first Prisme was made, did in the second Prisme suffer a Refraction considerably greater then the light tending to the other end. And so the true cause of the length of that Image was detected to be no other, then that Light consists of Rays differently refrangible, which, without any respect to a difference in their incidence, were, according to their degrees of refrangibility, transmitted towards divers parts of the wall. When I understood this, I left off my aforesaid Glass works; for I saw, that the perfection of Telescopes was hitherto limited, not so much for want of glasses truly figured according to the prescriptions of Optick Authors, (which all men have hitherto imagined,) as because that Light it self is a Heterogeneous mixture of differently refrangible Rays http://www.newtonproject.sussex.ac.uk/view/texts/normalized/NATP00006

70. http://www.departments.bucknell.edu/history/carnegie/newton/refraction.html “light consists of rays differently refrangible”

71. 4 http://www.princeton.edu/~his291/Experimentum_Crucis.html F*@% you Aristotle.

72. What is light made of: Part Two

73. Light is a Particle.

74. Newton said so.

75. Light is a Wave.

76. Thomas Young, Genius.

77. Particle theory wasn’t fully satisfying to some.

78. Waves interfere and reinforce.

79. 5 Young’s Double Slit experiment, with “a slip of card”

80. 5 Light shines WHERE IT SHOULDN’T

81. No sound without air. But light and magnetism. What is the wave medium?!

82. 1887 10’ There is no medium.

83. First American to receive the Nobel Prize! (1907) This was 2 years after Einstein’s miracle year.

84. "According to the assumption to be contemplated here, when a light ray is spreading from a point, the energy is not distributed continuously over ever-increasing spaces, but consists of a finite number of energy quanta that are localized in points in space, move without dividing, and can be absorbed or generated only as a whole." It was not really well received. It took 20 years before science came along.

85. What is Electricity?

86. The first battery, by Volta: 1799 Electricity is dubbed “a fluid” that flows from charged bodies

87. 3 Robert Millikan’s 1911 oil drop experiment showed electricity was discrete. He won the Nobel in 1923.

88. 3 Robert Millikan’s 1911 oil drop experiment showed electricity was discrete. He won the Nobel in 1923.

89. The lowest common denominator of many, many drops was the charge of an electron.

90. As of 2008, the accepted value for the elementary charge is 1.602176487(40)×10−19 Coulombs where the 40 indicates the uncertainty of the last two decimal places. In his Nobel lecture, Millikan gave his measurement as 1.5924(17)×10−19 Coulombs The difference is less than one percent, but it is more than five times greater than Millikan's standard error, so the disagreement is significant. Science makes mistakes.

91. We have learned a lot from experience about how to handle some of the ways we fool ourselves. One example: Millikan measured the charge on an electron by an experiment with falling oil drops, and got an answer which we now know not to be quite right. It's a little bit off because he had the incorrect value for the viscosity of air. It's interesting to look at the history of measurements of the charge of an electron, after Millikan. If you plot them as a function of time, you find that one is a little bit bigger than Millikan's, and the next one's a little bit bigger than that, and the next one's a little bit bigger than that, until finally they settle down to a number which is higher. Why didn't they discover the new number was higher right away? It's a thing that scientists are ashamed of - this history - because it's apparent that people did things like this: When they got a number that was too high above Millikan's, they thought something must be wrong - and they would look for and find a reason why something might be wrong. When they got a number close to Millikan's value they didn't look so hard. And so they eliminated the numbers that were too far off, and did other things like that.. “we fool ourselves” – Richard Feynman

92. What is an Atom?

93. Not widely accepted.

94. Breaking things down.

95. All mixed up.

96. 9 Ernest Rutherford’s 1911 Gold Foil experiment.

97. It was quite the most incredible event that has ever happened to me in my life. It was almost as incredible as if you fired a 15-inch shell at a piece of tissue paper and it came back and hit you. On consideration, I realized that this scattering backward must be the result of a single collision, and when I made calculations I saw that it was impossible to get anything of that order of magnitude unless you took a system in which the greater part of the mass of the atom was concentrated in a minute nucleus. It was then that I had the idea of an atom with a minute massive center, carrying a charge. —Ernest Rutherford

98. Quantum Wierdness.

99. Matter Waves, circa 1924.

100. 1 Claus Jönsson in 1961 demonstrated that beams of electrons acted just like beams of light.

101. Modern Theories did not arise from revolutionary ideas…introduced into the exact sciences from without… they have forced their way into research which was attempting consistently to carry out the programme of classical physics. They arose out of its very nature. Werner Heisenberg

102. Eratosthenes of Cyrene, 194 BC Jean-Bernard-Léon Foucault , 1851 Galileo Galilei, 1600s Galileo Galilei, 1600s Henry Cavendish, 1781 Albert Michelson, 1887 Isaac Newton, 1671 Thomas Young, 1803 Robert Millikan, 1909 Ernest Rutherford, 1911 Claus Jönsson, 1961