Washington College
Chestertown, Maryland
Instructor: Juan Lin
Textbooks: R.Wolfson : Simply Einstein (SE)
D. Styer: The strange world of Quantum Mechanics (QM)
Office: Dunning N203
Office hours: TuWTh: 3:00 - 3:45 pm. or by appointment.
Lectures: A minimum of 90%
Laboratory: 100%
Course grade:
Assignments and Experiments: 25%
Quizzes : 45%
Final Project: 20%
Attendance and Class participation: 10%
One of the main goals of this course is to understand the great achievements of Galileo, Newton and Einstein and others in shaping modern physics. In the first half of the semester we will analyze motion and explain the experiments, assumptions and predictions of the special and general theories of relativity. In the second half of the semester, we will discuss the quantum ideas needed to explain the strange world of the atom.
"We can imagine that this complicated array of moving things which constitutes" the world" is something like a great chess game being played by the gods, and we are observers of the game. We do not know what the rules of the game are; all we are allowed to do is to watch the playing. Of course, if we watch long enough, we may eventually catch on to a few of the rules. The rules of the game are what we mean by fundamental physics." R. Feynman
Mathematics Background
Knowledge of math you may need for this course. Here is a list of concepts:
Four arithmetic operations ( +, -, *, / )
Square root (Ex. sqrt(5))
Powers of ten (Ex. 10 ^5 or 10^-2)
Unit conversion, (Ex. hours to seconds)
Tentative Program
Jan. 21 - 27: Read Chapters 1 - 3 of SE
"I can teach you the words but not the truths, which are things." Galileo
Eratosthenes from Egypt measured the size of earth around
235 B.C. For an interesting description of his contributions and that of other
important physicists please refer to the web site, Famous
people. If you want to know more
about Galileo's fascinating life please go to the Galileo Project.
On reference frames , check Relative Motion. For a visual review of kinematics, forces and vectors visit, Glenbrook Multimedia Physics or DVA. About projectiles and orbits, visit ProjOrb.
"When..
I consider that a stone, falling from rest, successively acquires new increments
of speed, why should I not believe that those additions are made by the simplest
and most evident rule? For if we look into this attentively, we can discover
no simpler addition and increase than that which is added on always in the
same way." Galileo
1. Choose a partner to do an experiment. It is all right if you wish to do the experiment by yourself, but groups larger than two are unacceptable.
2. All items needed to carry out an experiment will be specified in the handout. It is your responsibility to get them (difficult to find items will be provided). Some experiments require a little bit of planning. All of them should be repeated two or more times to make sure that your results are reproducible and reliable. Do the experiments with great care and be honest to report what you have measured. All data and analyis must be original, not borrowed.
3. You rarely "get it right" the first time you do an experiment. Sometimes you may discover after finishing a series of measurements that an error occurred. Go back and try again!
4. The write-up should contain a brief description of your set-up, a table of data, calculations (with % error estimates), and a discussion of results. To receive a report grade all participants must type and sign the pledge:
I have abided by Washington College Honor's Code while completing this work.
Signatures: _______________________________ (both members)
5. The report should be typed and never to exceed two pages of text, graphs aside. The discussion of results is of great importance; it must include, among other things, a personal evaluation of how the experiment was carried out and what valuable insights it provided you. Be candid but thoughtful. Staple all pages, and be sure to include your names.
6. Deadlines will be strictly enforced. Late reports will not be accepted.
Jan. 28 - Feb. 3: Read Chapters 4 and 5 of SE.
"I do not know what I may appear to the world; but to myself I seem to have been only a boy, paying at the seashore, and directing myself in now and then, finding a smoother pebble or a prettier shell than ordinary, whilst the great ocean of truth lay all undiscovered before me." I. Newton
"Physics should be made as simple as possible, but not simpler." A. Einstein
| Due Wed., Jan. 30 |
Experiment #1 & First Homework Assignment |
Newton is considered by many the greatest physicist of all time. Please check Newton's biography for a fascinating portrait of his life and times. On electric field lines, visit EFieldLines. The magnetic field lines of a magnet can be seen in BarMagnet.
| Wednesday, February 6: Quiz |
Light is a transverse wave, sound a longitudinal one. Check their differences in T& L wave. Propagation of an electromagnetic can be seen in EM. Waves can be added or substracted and they can interfere with each other. View these effects in Superposition 1, Superposition 2 and Interference.
Feb. 4 - 10 : Read Chapters 6 - 7 of SE.
"The object of all science, whether natural science or psychology, is to coordinate our experiences and to bring them into a logical system." A. Einstein
"My scientific work is motivated by an irresistible longing to understand the secrets of nature and by no other feelings" A. Einstein
Einstein, together with Newton and Maxwell, is considered by many to be one of the greatest physicists of all time. In Albert Einstein you will find a wonderful tribute to his life and work.
You can read about the celebrated Michelson-Morley experiment (to test the existence of ether) in Albert Michelson. Also check the simulation Michelson.
| Due Wed., Feb. 13 |
Experiment #2 & Homework Assignment |
In NASA's program, Solar Exploration, you can view planetary orbits at different scales of magnification and at different angles.
Feb. 11 - 17: Read Chapters 8 - 10 of SE.
"The important thing is not to stop questioning. Curiosity has its own reason for existing. One cannot help but be in awe when he [or she] contemplates the mysteries of eternity, of life, of the marvelous structure of reality. It is enough it one tries merely to comprehend a little of this mystery every day. Never lose a holy curiosity. " A. Einstein
The simulations Simultaneous Events, Clocks and TD1 and TD2 show measurements done in different inertial frames. You will also find visual explanations of relativity in Casacolorado.
Moving objects shorten along the direction of motion. Simulations are provided in LC1 and LC2. The center of mass of a body can be understood from the simulation CM. To understand the connection between energy and mass, visit E =mc^2.
| Wednesday, Feb. 20: Quiz |
Feb. 18 - Feb. 24: Read Chapters 9 - 11 of SE.
"I was sitting in a chair in the patent office at Bern when all of a sudden a thought occurred to me: ' If a person falls freely he will not feel his own weight.' I was startled. This simple thought made a deep inpression on me. It impelled me toward a theory of gravitation." A. Einstein
Events occur in four-dimensional Spacetime.
| Due Monday, March 3 |
Experiment #3 & Homework Assignment |
Feb. 25 - March 2 : Read Chapters 12 - 14 of SE.
"If you will not take the answer too seriously, and consider it only as a kind of joke, then I can explain [general relativity] as follows. It was formely believed that if all material things disappeared out of the universe, time and space would be left. According to the relativity theory, however, time and space disappear together with the things." A. Einstein
The principle of equivalence is demonstrated in PEq. Images and explanations of distant galaxies exhibiting the lensing effect can be seen at the SpaceTelescope Science Institute. To maintain an object on a rotating disk you need a radial force pointing inwards. In Gravitational time dilation you will find a clear explanation of position-dependent clock rates near a gravitating body. To understand the origin of tidal forces, check TF. In STC you will find the curvature of spacetime in projectile motion.
| Wednesday, March 5: Quiz |
Spring Break: March 10 - 16
March 3 - 9: Read Chapters 15 - 16 of SE.
"There exists in the heavens therefore dark bodies, as large as and perhaps as numerous as the stars themselves. Rays from a luminous star having the same density as the Earth and a diameter 250 times that of the Sun would not reach us because of its gravitational attraction; it is therefore possible that the largest luminous bodies in the Universe may be invisible for this reason." Pierre Simon Laplace, 1796.
"What would physics look like without gravitation?" A. Einstein
" In my entire scientific life, extending over forty-five years, the most shattering experience has been the realization that an exact solution of Einstein's equations of general relativity, discovered by the New Zeeland mathematician, Roy Kerr, provides the absolutely exact representation of untold numbers of massive black holes that populate the universe. This "shuddering before the beautiful," this incredible fact that a discovery motivated by a search after the beautiful in mathematics should find its exact replica in Nature, persuades me to say that beauty is that to which the human mind responds at its deepest and most profound." S. Chandrasekhar, 1975.
1. The notion of escape speed can be understood in terms of energy conservation. Embedding diagrams allow us to visualize the curvature of a two-dimensional surface in three-dimensional flat space: visit EmDi. The horizon or Schwarzschild radius is shown in EmBH. There is a simple animation of gravitational red shift in CasaGrs.
2. About X-ray astronomy and Cygnus-X-1, visit X-rayAstro and CygX1. Stellar evolution shows how stars evolve. To understand the Doppler effect, refer to NTNUDoppler.
3. Visit Chandra to view animations of black hole formation. To explore the vicinity of a black hole, check Nemiroff. The collapse of two black holes into one produces Gravitational Waves (T& L wave). Black holes can also evaporate, BHEv.
4. Elementary particles are the fundamental building blocks of nature. In ElemPart you will find a brief description. The quest for a grand theory to unify all forces of nature started with Einstein. For a brief review of this program, visit UF. Clear explanations of nuclear fission and nuclear fusion processes with java applets can be found in the site Thinkquest. To know about the basic constituents of nature, please check the Fermi National Lab site.
| Due Fri., March 21 |
Experiment #4
|
March 17 - 23: Read Chapters 1 - 3 of QM.
"I can safely say that nobody understands quantum mechanics." R. Feynman
Emission Spectra of elements are discrete. The quantization of light is shown in Photoelectric Effect. About magnetic field lines and ways to produce them, check MField. The precession of a spin or nuclei in a magnetic field is shown in NMR .
Wednesday, March 26: Quiz & Homework Assignment |
March 24 - March 30: Read Chapters 4 - 6 of QM.
" The theory of quantum electrodynamics has now lasted for more than fifty years... At the present time I can proudly say that there is no significant difference between experiment and theory!" R. Feynman
The Stern-Gerlach experiment is shown in SG.
April 2: Advising Day
| Due Monday, April 7 |
Experiment #5 & Homework Assignment |
March 31 - April 6: Read Chapters 7 and 8 of QM.
The Stern-Gerlach software developed by Styer can be found in Spins (developed by David McIntyre).
Heisenberg's uncertainty principle explains Braginsky's standard quantum limit. Wave-particle duality is a central concept in the quantum world and can be observed in the simulations Wave Diffraction and Electron Diffraction. For a rather technical explanation of Schroedinger's cat, visit NIST.
| Wednesday, April 9: Quiz |
April 7 - 13: Read Chapters 7 - 9 of QM.
"Well, here is the organizing principle of the microworld: Explore all paths!" E. F. Taylor
Vector addition is ilustrated in VA.
April 14 - 20: Read Chapters 10 - 12 of QM.
Due Monday, April 21 |
Experiment #6 & Homework Assignment |
The Aharonov-Bohm effect is explained in AB. Another quantum paradox is Wheeler's delayed choice experiment, DC.
| Wednesday, April 23: Quiz |
April 21 - May 1: Read Chapters 13 - 15 of QM.
"Thirty-one years ago [1949!] Dick Feynman told me about his 'sum over histories" version of quantum mechanics. "The electron does anything it likes," he said. "It just goes in any direction at any speed, forward or backward in time, however it likes, and then you add up the amplitudes and it gives you the wave-function" (probability amplitude). I said to him, "You are crazy." But he wasn't." F. Dyson, 1980.
J.J. Thomson's 1906 Nobel lecture on the discovery of the electron is worth reading. For a brief review of Feynman diagrams and virtual particles, visit VirPar and FeyDia. Information about classical and quantum cryptography can be found in Qubit.
| Due Monday,
April 28 |
Homework Assignment |
| Final Project |