l1_p480w_s11.notebook January 24, 2011 Experimental Physics 480W 4 experiments: i) Optical pumbing in Rb (zeeman and hyperfine splitting) ii) Pulsed NMR iii) Plasma discharge physics, and ion acoustic waves iv) Laser Spectroscopy, hfs of Rb
Syllabus Stuff Goal #1 Do good experimental work. Goal #2 Write Mathematical prose well.
Aug 26 2:59 PM 1 l1_p480w_s11.notebook January 24, 2011
Homework! No Homework!
but there are tutorial assignments!
type I type II readings for discussions
LaTeX example problems: e.g., format the following, and...
Jan 2412:04 PM 2 l1_p480w_s11.notebook January 24, 2011
I. LOGISTICS......
need to compose groups I and II soon......
Jan 2410:25 AM 3 l1_p480w_s11.notebook January 24, 2011
II. about Experimental Physics.....
Q: what are these scholars telling us about science and how it advances?
``Science arises out of practical experience. It is an attempt to communicate acquired experience with the maximum economy of ﴿statement.'' A.P.Usher, A history of mechanical inventions ﴾Dover 1954
"The life of a great scientist in his laboratory is not, as many may think, a peaceful idyll. More often, it is a bitter battle with things, with one's surroundings, and above all with oneself. A great discovery does not leap completely achieved from the brain of the scientist, as Minerva sprang, all panoplied, from the head of Jupiter; it is the fruit of accumulated preliminary work." Marie Curie
"we devote ten percent of our time to socalled "Friday evening" experiments. I just do all kinds of crazy things that probably won’t pan out at all, but if they do, it would be really surprising. Geim did frog levitation as one of these experiments, and then we did gecko tape together. There are many more that were unsuccessful and never went anywhere ﴾though I still had a good time thinking about and doing those experiments, so I love .﴿them no less than the successful ones
This graphene business started as that kind of Friday evening experiment. We weren’t hoping for much, and when I gave it to a student, it initially failed. Then we had what you could call a stream of coincidences that basically brought us some very remarkable results quite quickly —within a week or so. Then we decided to continue on a more serious basis. " Andre Geim
Sep 2 7:44 AM 4 l1_p480w_s11.notebook January 24, 2011
From, ``NEW LEARNING AND NEW IGNORANCE''
What proved important ﴾and that slowly﴿ about the new astronomy was not the mere alteration in our map of space but the methodological revolution which verified it. This is not sufficiently described as a change from dogmatism to empiricism. Mere empiricists like Telesius or Bacon achieved nothing. What was fruitful in the thought of the new scientists was the bold use of mathematics in the construction of hypotheses, tested not by observation simply but by controlled observation of phenomena that could be precisely measured. On the practical side it was this that delivered Nature into our hands. C.S. Lewis, English Literature in the Sixteenth Century Excluding Drama
Questions for discussion: a﴿ can one give concrete examples of science arising from experience? b﴿ how does the struggle with self come into science? That sounds so subjective! Is physics subjective? c﴿Is physics, finally, all about mathematical models that fit with observation? Yes? No? Hint: is there a difference between observation and experiment? What is `experiment?'
Jan 2411:02 AM 5 l1_p480w_s11.notebook January 24, 2011
http://www.youtube.com/watch?v=mxw_fmB2KA&feature=player_embedded
A snippet from Geim's NPL
Aug 26 10:36 PM 6 l1_p480w_s11.notebook January 24, 2011
The gap between having fun and getting to results is bridged by determination and patient, hard work
Jan 2410:54 AM 7 l1_p480w_s11.notebook January 24, 2011
III. Writing in Science:
the principal means by which you communicate your work, the principal means by which the yield of new knowledge is made known.
It is a skill that we must inculcate
Aug 26 10:36 PM 8 l1_p480w_s11.notebook January 24, 2011
Writing in Science: to what purpose? ﴿.a﴿ convey ﴾correctly, accurately, etc knowledge, information ﴿b﴿ teach, instruct what is ﴾now understood.
Are these the same things?
please make copy edits on the snippet below:
story of Shunko!
Jan 2410:59 AM 9 l1_p480w_s11.notebook January 24, 2011
But what about Mathematical Prose?
how to create something like ......
?
Jan 2411:34 AM 10 l1_p480w_s11.notebook January 24, 2011
Some tutorial questions...... ﴿Group I: ﴾quantum background would be useful
pose we could trap a gas of neutral atoms ﴾at room temperature﴿ and so subject them to external' magnetic fields, light, electromagnetic radiation of any desired magnitude and frequency. The ground state of the atom is has a single `s' electron. The wavelength of the photon connecting the ground state to the first excited state, is, say, 794.8nm. Is there any way to get the atoms to absorb a photon of frequency, say, 40 kHz ﴾that's a much longer wavelength﴿. How would you do it, just for fun, and what would you learn thereby?
﴿Group II:﴾statistical mechanics background would be useful
s'pose we could measure the velocity distribution function ﴾evdf﴿ of electrons created by a kabillion ionization events between energetic electrons and cold neutral gas atoms, created in a magnetic confinement chamber so as to make plasma of electrons, ions, and neutral gas atoms. Describe the resulting electron evdf in as much detail and sophistication as you can. Would the electrons even have a temperature? If so, would they be hotter, colder, or the same as the temperature of the neutral gas in the chamber? How would you try to find out, and what would you learn thereby?
Jan 2411:05 AM 11 l1_p480w_s11.notebook January 24, 2011
We will use LaTeX, with accompanying style files to help us with AIP formatting....first assignment will be done in lab tomorrow!
Jan 2412:00 PM 12 l1_p480w_s11.notebook January 24, 2011
Jan 2411:32 AM 13