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Teoretisk fysik
Institutionen för fysikHelsingfors Universitet
12.11. 2008Paul Hoyer
530013 Presentation av de fysikaliska vetenskaperna (3 sp, 1 sv)
Kursbeskrivning: I kursen presenteras de fysikaliska vetenskaperna med sina huvudämnen astronomi, fysik, geofysik, meteorologi samt teoretisk fysik. Den allmänna studiegången presenteras samt en inblick i arbetsmarkanden för utexaminerade fysiker ges.
Kursens centrala innehåll: Kursen innehåller en presentation av de fysikaliska vetenskapernas huvudämnes uppbyggnad samt centrala forskningsobjekt. Presentationen ges av institutionens lärare samt av utomstående forskare och fysiker i industrin.
Centrala färdigheter: Att kunna tillgodogöra sig en muntlig presentation sam föra en diskussion om det presenterade temat.
Kommentarer: På kursen kan man även behandla speciella ämnesområden, såsom: speciella forskningsområden inom fysiken samt specifika önskemål inom studierna.
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Bakgrund
Den fortgående specialiseringen inom naturvetenskaperna ledde till att teoretisk fysik utvecklades till ett eget delområde av fysiken
Professurer i teoretisk fysik år 1900: 8 i Tyskland, 2 i USA,1 i Holland, 0 i Storbritannien
Teoretisk fysik är egentligen en metod (jfr. experimentell och numerisk fysik) som täcker alla områden av fysiken:
Kondenserad materieOptikKärnfysikHögenergifysik,...
Professorer i teoretisk fysik år 2008: Talrika! Även forskningsinstitut för teoretisk fysik (Nordita @ Stockholm, Kavli @ Santa Barbara,...)
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Rutherford 1910: “How can a fellow sit down at a table and calculate something that would take me, me, six months to measure in the laboratory?”
1928: Dirac realized that his equation in fact describes two spin-1/2 particles with opposite charge. He first thought the two were the electron and the proton, but it was then pointed out to him by Igor Tamm and Robert Oppenheimer that they must have the same mass, and the new particle became the anti-electron, the positron. It was discovered by Carl Anderson in 1932 (Nobel Prize 1936):
Rutherford 1933: “ It seems to me that in some way it is regrettable that we had a theory of the positive electron before the beginning of the experiments... I would have liked it better if the theory had arrived after the experimental facts had been established.”
Cloud chamber photograph by C.D. Anderson of the first positron ever identified. A 6 mm lead plate separates the upper half of the chamber from the lower half. The positron must have come from below since the upper track is bent more strongly in the magnetic field indicating a lower energy
Kring nyttan av teoretisk fysik
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The QED experience
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In his report to the 12th Solvay Congress (Brussels, 1961) on “The Present Status of Quantum Electrodynamics” (QED), Feynman called for more insight and physical intuition in QED calculations:
“It seems that very little physical intuition has yet been developed in this subject. In nearly every case we are reduced to computing exactly a coefficient of some specific term. We have no way to get a general idea of the result to be expected. To make my view clearer, consider, for example, the anomalous electron moment, (g–2)/2 = α/2π – 0.328α2/π2 . We have no physical picture by which we can easily see that the correction is roughly α/2π , in fact, we do not even know why the sign is positive (other than by computing it). In another field we would not be content with the calculation of the second order term to three significant figures without enough understanding to get a rational estimate of the order of magnitude of the third. We have been computing terms like a blind man exploring a new room, but soon we must develop some concept of this room as a whole, and to have some idea of what is contained in it. As a specific challenge, is there any method of computing the anomalous moment of the electron which, on first rough approximation, gives a fair approximation to the α term and a crude one to α2 ; and when improved, increases the accuracy of the α2 term, yielding a rough estimate of α3 and beyond?”
gµ/2 = 1.0 011 659 214 (8)(3) e /2mµ
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Teori och experiment är nära förbundna: I det längre loppet är fysiker inte intresserade av teorier som inte kan verifieras genom mätningar.
Teori drivs av experiment: Elektromagnetism (Maxwell), speciell relativitetsteori (Einstein), Kvantmekanik (Planck, Einstein, Bohr,...)...
och vice versa: Allmän relativitetsteori (Einstein), antimaterie (Dirac), ...
Framgångarna med att förutsäga och förklara experimentella data har givit teoretisk fysik hög status: Många nobelpris ges till teoretiska fysiker
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About Nobelprize.org Privacy Policy Terms of Use Technical Support RSS The Official Web Site of the Nobel Foundation Copyright © Nobel Web AB 2008
"for the discovery of the
mechanism of
spontaneous broken
symmetry in subatomic
physics"
"for the discovery of the origin of the broken symmetry
which predicts the existence of at least three families of
quarks in nature"
The Nobel Prize in Physics 2008
Photo: Universtity of Chicago Photo: KEK Photo: Kyoto University
Yoichiro Nambu Makoto Kobayashi Toshihide Maskawa
1/2 of the prize 1/4 of the prize 1/4 of the prize
USA Japan Japan
Enrico Fermi Institute, University
of Chicago
Chicago, IL, USA
High Energy Accelerator Research
Organization (KEK)
Tsukuba, Japan
Kyoto Sangyo University; Yukawa
Institute for Theoretical Physics
(YITP), Kyoto University
Kyoto, Japan
b. 1921
(in Tokyo, Japan)
b. 1944 b. 1940
Titles, data and places given above refer to the time of the award.
http://nobelprize.org/cgi-bin/print?from=%2Fnobel_prizes%... 10/22/08 10:26 AM
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All Nobel Laureates in Physics
The Nobel Prize in Physics has been awarded to 183 individuals since 1901. (John Bardeen was awarded the prize in
both 1956 and 1972.) Click on a name to go to the Laureate's page.
Jump down to: | 1980 | 1960 | 1940 | 1920 | 1901 |
2008 - Yoichiro Nambu, Makoto Kobayashi, Toshihide Maskawa
2007 - Albert Fert, Peter Grünberg
2006 - John C. Mather, George F. Smoot
2005 - Roy J. Glauber, John L. Hall, Theodor W. Hänsch
2004 - David J. Gross, H. David Politzer, Frank Wilczek
2003 - Alexei A. Abrikosov, Vitaly L. Ginzburg, Anthony J. Leggett
2002 - Raymond Davis Jr., Masatoshi Koshiba, Riccardo Giacconi
2001 - Eric A. Cornell, Wolfgang Ketterle, Carl E. Wieman
2000 - Zhores I. Alferov, Herbert Kroemer, Jack S. Kilby
1999 - Gerardus 't Hooft, Martinus J.G. Veltman
1998 - Robert B. Laughlin, Horst L. Störmer, Daniel C. Tsui
1997 - Steven Chu, Claude Cohen-Tannoudji, William D. Phillips
1996 - David M. Lee, Douglas D. Osheroff, Robert C. Richardson
1995 - Martin L. Perl, Frederick Reines
1994 - Bertram N. Brockhouse, Clifford G. Shull
1993 - Russell A. Hulse, Joseph H. Taylor Jr.
1992 - Georges Charpak
1991 - Pierre-Gilles de Gennes
1990 - Jerome I. Friedman, Henry W. Kendall, Richard E. Taylor
1989 - Norman F. Ramsey, Hans G. Dehmelt, Wolfgang Paul
1988 - Leon M. Lederman, Melvin Schwartz, Jack Steinberger
1987 - J. Georg Bednorz, K. Alex Müller
1986 - Ernst Ruska, Gerd Binnig, Heinrich Rohrer
1985 - Klaus von Klitzing
1984 - Carlo Rubbia, Simon van der Meer
1983 - Subramanyan Chandrasekhar, William A. Fowler
1982 - Kenneth G. Wilson
1981 - Nicolaas Bloembergen, Arthur L. Schawlow, Kai M. Siegbahn
1980 - James Cronin, Val Fitch
1979 - Sheldon Glashow, Abdus Salam, Steven Weinberg
1978 - Pyotr Kapitsa, Arno Penzias, Robert Woodrow Wilson
1977 - Philip W. Anderson, Sir Nevill F. Mott, John H. van Vleck
1976 - Burton Richter, Samuel C.C. Ting
1975 - Aage N. Bohr, Ben R. Mottelson, James Rainwater
1974 - Martin Ryle, Antony Hewish
1973 - Leo Esaki, Ivar Giaever, Brian D. Josephson
1972 - John Bardeen, Leon N. Cooper, Robert Schrieffer
1971 - Dennis Gabor
1970 - Hannes Alfvén, Louis Néel
1969 - Murray Gell-Mann
1968 - Luis Alvarez
1967 - Hans Bethe
1966 - Alfred Kastler
1965 - Sin-Itiro Tomonaga, Julian Schwinger, Richard P. Feynman
1964 - Charles H. Townes, Nicolay G. Basov, Aleksandr M. Prokhorov
1963 - Eugene Wigner, Maria Goeppert-Mayer, J. Hans D. Jensen
1962 - Lev Landau
1961 - Robert Hofstadter, Rudolf Mössbauer
1960 - Donald A. Glaser
1959 - Emilio Segrè, Owen Chamberlain
1958 - Pavel A. Cherenkov, Il´ja M. Frank, Igor Y. Tamm
1957 - Chen Ning Yang, Tsung-Dao Lee
1956 - William B. Shockley, John Bardeen, Walter H. Brattain
1955 - Willis E. Lamb, Polykarp Kusch
1954 - Max Born, Walther Bothe
1953 - Frits Zernike
1952 - Felix Bloch, E. M. Purcell
1951 - John Cockcroft, Ernest T.S. Walton
1950 - Cecil Powell
1949 - Hideki Yukawa
1948 - Patrick M.S. Blackett
1947 - Edward V. Appleton
1946 - Percy W. Bridgman
1945 - Wolfgang Pauli
1944 - Isidor Isaac Rabi
1943 - Otto Stern
http://nobelprize.org/cgi-bin/print?from=%2Fnobel_prizes%... 10/22/08 10:37 AM
Nobel Prizes in theoretical physics, 1989 – 2008
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HOW to BECOME a GOOD THEORETICAL PHYSICIST
by Gerard 't Hooft
http://www.phys.uu.nl/~thooft/theorist.html#aqmechanics
This is a web site (still under construction) for young students - and anyone else - who are (like me) thrilled by the challenges posed by real science, and who are - like me - determined to use their brains to discover new things about the physical world that we are living in. In short, it is for all those who decided to study theoretical physics, in their own time.
It so often happens that I receive mail - well-intended but totally useless - by amateur physicists who believe to have solved the world. They believe this, only because they understand totally nothing about the real way problems are solved in Modern Physics. If you really want to contribute to our theoretical understanding of physical laws - and it is an exciting experience if you succeed! - there are many things you need to know. First of all, be serious about it. All necessary science courses are taught at Universities, so, naturally, the first thing you should do is have yourself admitted at a University and absorb everything you can. But what if you are still young, at School, and before being admitted at a University, you have to endure the childish anecdotes that they call science there? What if you are older, and you are not at all looking forward to join those noisy crowds of young students ?
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Theoretical Physics is like a sky scraper. It has solid foundations in elementary mathematics and notions of classical (pre-20th century) physics. Don't think that pre-20th century physics is "irrelevant" since now we have so much more. In those days, the solid foundations were laid of the knowledge that we enjoy now. Don't try to construct your sky scraper without first reconstructing these foundations yourself.
The first few floors of our skyscraper consist of advanced mathematical formalisms that turn the Classical Physics theories into beauties of their own. They are needed if you want to go higher than that. So, next come many of the other subjects listed below. Finally, if you are mad enough that you want to solve those tremendously perplexing problems of reconciling gravitational physics with the quantum world, you end up studying general relativity, superstring theory, M-theory, Calabi-Yau compactification and so on. That's presently the top of the sky scraper. There are other peaks such as Bose-Einstein condensation, fractional Hall effect, and more. Also good for Nobel Prizes, as the past years have shown.
Gerard 't Hooft (cont.)
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# Languages# Primary Mathematics# Classical Mechanics# Optics# Statistical Mechanics and Thermodynamics# Electronics# Electromagnetism# Quantum Mechanics# Atoms and Molecules# Solid State Physics# Nuclear Physics# Plasma Physics# Advanced Mathematics# Special Relativity# Advanced Quantum Mechanics# Phenomenology# General Relativity# Quantum Field Theory# Superstring Theory
Gerard 't Hooft (cont.)LIST OF SUBJECTS, IN LOGICAL ORDER
It should be possible, these days, to collect all knowledge you need from the internet. Problem then is, there is so much junk on the internet. Is it possible to weed out those very rare pages that may really be of use? I know exactly what should be taught to the beginning student. The names and topics of the absolutely necessary lecture courses are easy to list, and this is what I have done below.
Note that this site NOT meant to be very pedagogical. I avoid texts with lots of colorful but distracting pictures from authors who try hard to be funny. Also, the subjects included are somewhat focused towards my own interests.
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Sheldon GlashowArthur G.B. Metcalf Professor of Physics at Boston University and winner of the 1979 Nobel Prize in Physics
http://www.pbs.org/wgbh/nova/elegant/view-glashow.html
Viewpoints on String Theory
NOVA: In the '60s and '70s when there were tremendous breakthroughs in particle physics, how would you describe the relationship between theory and experiment?
Glashow: I was at the University of California in Berkeley from roughly 1963 to 1966 as a professor, and I remember clearly that the experimenters and the theorists were in very close contact. Luis Alvarez, who was a very distinguished and brilliant experimental physicist, would hold a meeting at his home on a more or less weekly basis to which he would invite his experimental group and a few of the local theorists, myself included. It was a very wonderful experience. Each week or every couple of weeks we would hear about the latest discoveries—there would always be one or two—and we were trying to help the experimenters interpret their data just as they were posing questions to us about what these strange effects they saw in the laboratory were. It was a very intimate relationship.
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This intimacy continued and it continues today certainly at my university. But oddly there has been a new development, in which a new class of physicists is doing physics, undeniably physics, but physics of a sort that does not relate to anything experimental. This new class is interested in experiment from a cultural but not a scientific point of view, because they have focused on questions that experiment cannot address.
So this is a change. It's something that began to develop in the '80s, grew in the '90s, and today attracts many of the best and brightest physicists. It's called superstring theory and it is, so far as I can see, totally divorced from experiment or observation. If not totally divorced, pretty well divorced. They will deny that, these string theorists. They will say, "We predicted the existence of gravity." Well, I knew a lot about gravity before there were any string theorists, so I don't take that as a prediction.
NOVA - Glashow (cont.)
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Richard Feynman
The Douglas Robb Memorial Lectures
Home Programmes Science Lectures Richard Feynman
Chosen by the New Scientist - best on-line videos 2007. A set of four priceless archival video recordings from the University of
Auckland (New Zealand) of the outstanding Nobel prize-winning physicist Richard Feynman - arguably the greatest science
lecturer ever. Although the recording is of modest technical quality the exceptional personal style and unique delivery shine
through.
Richard Feynman Video - The Douglas Robb Memorial Lectures - Part 1: Photons -
Corpuscles of Light
A gentle lead-in to the subject, Feynman starts by discussing photons and their properties.
Richard Feynman Video - The Douglas Robb Memorial Lectures - Part 2: Fits of Reflection
and Transmission - Quantum Behaviour
What are reflection and transmission, and how do they work?
Richard Feynman Video - The Douglas Robb Memorial Lectures - Part 3: Electrons and their
Interactions.
Feynman diagrams and the intricacies of particle interaction.
Richard Feynman Video - The Douglas Robb Memorial Lectures - Part 4: New Queries
What does it mean, and where is it all leading?
Feynman gives us not just a lesson in basic physics but also a deep insight into the scientific mind of a 20th century genius
analyzing the approach of the 17th century genius Newton.
For the young scientist, brought up in this age of hi-tech PC / Power Point-based presentations, we also get an object lesson
in how to give a lecture with nothing other than a piece of chalk and a blackboard. Furthermore we are shown how to respond
with wit and panache to the technical mishaps that are part-and-parcel of the lecturer's life.
If you are unable to access the streaming video or would like a copy of the lectures, they are available from the University of
Auckland, contact [email protected], or The Tuva Trader.
Links To Other Information:
Auckland University
Physics Department
Order Video
These lectures are available on DVD
Feynman
The official Richard Feynman website
http://vega.org.uk/videøsubseries/8 11/2/08 11:40 AM
http://vega.org.uk/video/subseries/8
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the pleasure of finding things out!! so important. so many people
just accept other people's opinion instead of thinking by
themselve and be really independent. we need more people like
that.
This guy's intellect was so far beyond any of us, he was curious
about the nature of the universe and didn't depend on faith to
determine how the universe works. He depended on carefully
gathered data and observations. He studied hard and discovered
realities that were not obvious. He is not arrogant, he is
confident, and how could he not be? Feynman dealt with facts,
not superstitions and fables.
Great Stuff!
my goodness what an amazing childhood
The beauty that Feynman "sees" is the beauty of his intellect at
play with the object as thing outside of himself. The beauty that
SubscribeFrom: melah65
Added: June 10, 2007
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Richard Feynman
17THEORETICAL PHYSICS
Department of Physics
Faculty of Science
P.O .Box 64 (Gus ta f Hä l l s t röm in ka tu 2 )
F I -00014 UNIVERSITY OF HELSINKI
F INLAND
Suomeksi På svenska In English
Theoretical Physics
LOCATION AND CONNECTIONS
INFONI: Current Old numbers
CONTACT INFORMATION:
Department of Physics
P.O. Box 64 (Gustaf Hällströmin katu 2)
FIN-00014 University of Helsinki
FINLAND
Phone: +358-(0)9-191 50602
Fax: +358-(0)9-191 50610
E-mail (to secretary Mrs. Liisa Koivisto):
Theoretical Physics is a field of study separate from Physics. The compulsory lectures on mechanics,
electrodynamics, quantum physics and statistical physics, required for the Bachelor or Master degrees,
teach the basics about the laws of physics. Learning the skills needed for analytic and numerical
computations is emphasized. Special courses in particle physics, cosmology, general relativity,
mathematical physics and solid state physics are also offered on a regular basis.
The current research fields in theoretical physics are particle physics, cosmology, space physics, materials
physics, and nanoscience.
Search department or university site: Search!
Home pages: Department | Kumpula Campus | Faculty | University | Science Library | Send feedback
Last updated 14.02.2008
http://www.helsinki.fi/~tfo_www/ 11/5/08 11:44 AM
http://www.helsinki.fi/~tfo_www/
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