Here are some important results and useful websites organized by Chapter that we have found since our book was finished in 1999.

Through May, 2002

Chapter 2

A nice site about relativity with many other useful links has been prepared by Chris Hillman. There are also several references to notes on modern physics (even complete courses) that can be found on the web.

A measurement reported in 1999 confirmed that the speed of light is frequency independent to within a factor of 6 x 10 -21 . See B. E. Schaefer, Physical Review Letters vol. 82, p. 4964(1999). Einstein is still correct!

Chapter 3

The October 1999 issue of Physics Today was partially devoted to general relativity. An article entitled "Gravitational Radiation and the Validity of General Relativity" by Clifford Will is an excellent description of how the experimental result of detecting gravitational radiation affects general relativity. Following this article is one on the LIGO project. Both expand on the presentation we presented in the textbook. They report the LIGO facilities are completed, and measurements searching for astrophysical gravitational waves should being in 2002.

 

Chapter 6

A new demonstration of resonant tunneling [see Eq. (6.67)] has been performed by researchers at the U.S. Army’s Redstone Arsenal in Alabama. Normally, a 40-nm layer of silver (a conductor and therefore highly reflective) blocks 93% of incident light. But when a 145-nm layer of magnesium fluoride is placed between two 40-nm layers of silver, the transmission increases to 50%. Making conductors more transparent has a possible application in the transparent displays used in aviation and elsewhere. See The Industrial Physicist February 2000, pp. 6-8 and Opt. Photonics News, Sept 1999, p. 25.

Scanning tunneling microscopes have been used to produce sharp images of the structure of the high-temperature superconductor bismuth-strontium-calcium-copper-oxide. Teams of researchers at Berkeley and in Japan have made these images and are using them to study the role played by impurities in high-temperature superconductivity. See Physics Today March 2000 pp. 17-18 and the cover photo from that issue.

 

Chapter 8

An interesting account of Wolfgang Pauli's life can be read in an article in the Februrary 2001 issue of Physics Today (February, 2001, page 43-49). The article quotes Max Born as thinking that Pauli was, perhaps, an even greater scientist than Einstein.

 

Chapter 9

A Fermi-Dirac condensate (similar to a Bose-Einstein condensate but obeying Fermi-Dirac statistics) was made by Deborah Jin of the National Institute for Standards and Technology and Brian DeMarco of the University of Colorado. They trapped roughly one million potassium-40 atoms, each having a total spin of 9/2, at a temperature of less than one μK. Studying this new quantum degenerate state may help physicists better understand what happens in the interior of stars, including white dwarfs and neutron stars, where the density of fermions is high. See Physics Today, October 1999, pp. 17-18 and Scientific American, November 1999, pp. 37-39.

A good review of Bose-Einstein condensation written by Wolfgang Ketterle appeared in Physics Today, December 1999, pp. 30-42.

A research update on Bose-Einstein condensates (see textbook pp. 304-305) is found in the article "The Coolest Gas in the Universe) in Scientific American December 2000, pp. 92-97.

The 2001 Nobel Prize for Physics was awarded to Eric A. Cornell, Wolfgang Ketterle, and Carl E. Wieman for their work on Bose-Einstein condensation. See Thornton/Rex text pp. 304-305 for more details about the work done by these three physicists.

 

Chapter 10

A review article on free-electron lasers (see Thornton/Rex Chapter 10 pp. 322-323) appears in the January 2002 issue of Physics Today, pp. 35-41. The article covers the historical development and describes how tunable free-electron lasers now operate at wavelengths including infrared, visible, ultraviolet, and x-ray. Possible new applications in biophysics, industry and national defense are also discussed.

Superconducting buckyballs (Thornton/Rex pp. 350-351) have recently been made with superconducting transition temperatures as high as 117 K by a team of scientists at Lucent Technologies Bell Labs. See Science 293, 2432 (2001) and The Industrial Physicist, December 2001/January 2002, p. 9.

A team of Bell Labs researchers has found superconductivity in hole-doped buckyballs (C60) with transition temperatures as high as 52 K. This beats the old record of 42.5 K given in the textbook on page 351. A brief description of the discovery is found in Physics Today ,January 2001 pp. 15-16.

In June 1999, the Office of Naval Research awarded a grant to American Superconductor to design a high-Tc superconducting motor to be used in ship propulsion. The superconductors will be based on the bismuth-strontium-calcium copper oxide compound and will carry currents on the order of 108 A/m2. The new motor is designed to produce 25,000 hp (over 107 W), a fivefold increase from existing superconducting motors.

Carbon "nanotubes" based on the same structure as C60 fullerenes (see Figure 10.39) are being studied intensely for their novel conducting and structural properties. They exhibit a remarkable strength for their light weight and have been considered as tips for scanning probe microscopes. A review of recent developments was written by Cees Dekker in Physics Today, May 1999, pp. 22-28.

Carbon nanotubes (based on the carbon-60 structure discussed in Section 10.6 of the text) have been suggested for use in a number of applications, many of which are based on their unusual strength and electronic properties. Possible applications include use in transistors and diodes, field emitters in flat-panel displays, cell-phone amplifiers, and ion storage for batteries. For more information see Scientific American June 2000, pp. 40-41, and Scientific American December 2000, pp. 62-69.

In early 2001, superconductivity was discovered in magnesium diboride (MgB 2 ) with a superconducting transition temperature T c = 39 K. The result is significant because this is the highest T c ever found in a conventional, non-ceramic superconductor. MgB 2 behaves like a standard BCS-superconductor (see Section 10.5), including for example its isotope effect. This material is a good candidate for applications, despite its relatively low T c , because of its low material cost. See Physics Today April 2001, pp. 17-18, Scientific American June 2001 p. 24B, and The Industrial Physicist October/November 2001, pp. 22-23.

A review article on free-electron lasers (see Thornton/Rex Chapter 10 pp. 322-323) appears in the January 2002 issue of Physics Today, pp. 35-41. The article covers the historical development and describes how tunable free-electron lasers now operate at wavelengths including infrared, visible, ultraviolet, and x-ray. Possible new applications in biophysics, industry and national defense are also discussed.

Superconducting buckyballs (Thornton/Rex pp. 350-351) have recently been made with superconducting transition temperatures as high as 117 K by a team of scientists at Lucent Technologies Bell Labs. See Science 293, 2432 (2001) and The Industrial Physicist, December 2001/January 2002, p. 9.

 

Chapter 11

The U.S. photovoltaic industry wants to attain the goal of 10% of U.S. peak generation capacity by 2030. The key is probably to produce less costly thin-film alternatives, but they are difficult to mass produce. The cystalline-silicon technology is likely to dominate for at least another 10 years. See an interesting article in The Industrial Physicist, April/May 2003 issue online at http://www.tipmagazine.com/tip/INPHFA/vol-9/iss-2/p16.html.

The possibility of building more computing power into microchips by stacking them in layers was discussed by Thomas H. Lee in the January, 2002 Scientific American, pp. 52-59. If realized, this new technology could allow Moore's Law (Thornton/Rex p. 388) to continue for several more decades.

New thermoelectric materials (thermoelectricity is discussed in Chapter 11) known as clathrates have been developed recently. These new materials promise to work more efficiently that other thermoelectric devices available commercially. See American Scientist 89, 136-141 (2001).

The light-emitting diode (LED, see Chapter 11 p. 377 of text) is being used more widely as a bright, colorful, energy-efficient light source. An article describing current and possible future uses is in Scientific American February 2001, pp. 62-67.

A new Public Broadcasting System on Transistorized! was broadcast during 1999. A Teacher’s Guide with useful material was published by Lucent Technologies, and a website was established at www.pbs.org/transistor. Even though the production was directed towards K-12 school children, it could be a useful resource. The video can be ordered from PBS by calling 800-344-3337. The teacher’s guide was mailed by KTCA-TV National Productions, 172 E. 4th St., St. Paul, MN 55101.

A solar cell that can convert sunlight to electricity at a record setting 32.3% was reported late in 1999 by the Department of Energy’s National Renewable Energy Laboratory and by Spectrolab.

Lithography has been used for several years to help make microchips smaller and smaller. An interesting article entitled "Next-Generation Lithography" was written for The Industrial Physicist, June 1999, p. 18.

Afshin Partovi and colleagues at Lucent Technologies’ Bell Laboratories announced the development of a very small aperture laser (VSAL). They were able to shine laser light through a 250-nm hole on the end of a diode laser. The resulting beam may make it possible to read and write information with a density several times higher than that in existing digital video disks (DVDs). The results are described in The Industrial Physicist February 2000, p. 6.

The quantum Hall effect has been observed in organic materials. Possible applications include field-effect transistors for electronic circuits. See Physics Today May 2000 p. 23 and J.H. Schön, S. Berg, Ch. Kloc, B. Batlogg, Science 287, 1022 (2000).

He possibility of building more computing power into microchips by stacking them in layers was discussed by Thomas H. Lee in the January, 2002 Scientific American, pp. 52-59. If realized, this new technology could allow Moore's Law (Thornton/Rex p. 388) to continue for several more decades.

Researchers at Agere Systems in New Jersey have built a 100-mm-scale triode using carbon nanotubes. It is hoped that these devices can be plugged into an integrated circuit and used to power wireless communication devices. See Physics Today, July 2002, pp. 35-41.

Chapter 12

An interesting review of radiocarbon dating using 14C entitled "Fifty Years of Radiocarbon Dating" by R. E. Taylor was presented in American Scientist, vol. 88, p. 60 (2000), the January-February 2000 issue.

An interesting account of Wolfgang Pauli's life can be read in an article in the Februrary 2001 issue of Physics Today (February, 2001, page 43-49). The article quotes Max Born as thinking that Pauli was, perhaps, an even greater scientist than Einstein.

An interactive Chart of the Nuclides allows one to choose a particular nuclide and find useful information such as mass, spin, decay modes, half life, and cross sections.

In order to save space, we have eliminated the discussion of radiation safety, units, and hazards in the 2nd edition that we had in the first edition. A site produced and run by University of Michigan health physics students is a good source of information on radiation and health physics.

Chapter 13

We are sad to report that Glenn Seaborg passed away in February 1999. An interesting obituary about his life was written by his friend and colleague Albert Ghiorso in the August 1999 issue of Physics Today.

In a great surprise, scientists at Lawrence Berkeley National Laboratory discovered elements 116 and 118 in 1999. This surprising development had not been expected, except by theorist Robert Smolanczuk of Warsaw, Poland who convinced the LBNL scientists to search for them. The result gives nuclear physicists hope that previously inaccessible regions of previously unseen elements may be observed. An announcement of the discovery can be found on page 17 of the August 1999 Physics Today. See also Science, vol. 284, p. 1751(1999). But in summer 2001 LBNL scientists announced that they had to retract their discovery of element 118. Efforts at many laboratories were not able to reproduce the results, and that prompted the LBNL scientists to go back and reanalyze their original data. The result was that the evidence was not there (see Science, vol. 293, p.777(2001)).

In September 1999 a significant nuclear accident occurred in a uranium processing facility plant at Tokaimura, Japan. Workers apparently added too much enriched uranium together, and a nuclear chain reaction ignited. Dozens of emergency workers and nearby residents were treated at a hospital. See a news report in the December 1999 issue of Physics Today (page 51).

A host of new accelerators capable of creating powerful beams of short-lived radioactive nuclei promises nuclear physicists with a new tool capable of reaching previously inaccessible nuclear regions and the ability to probe totally new nuclear species. Two such machines presently exist (one at the Oak Ridge National Laboratory in Oak Ridge, Tennessee), and several other facilities will soon become available. See a report in Science, vol. 286, p. 28(1999).

 

Chapter 14

The October 2002 issue of Physics Today, p. 9, discussed new work on the cosmological upper limit of neutrino masses. The paper was by O. Elgaroy et al., Phys. Rev. Lett.89, 061301, 2002. The authors compared data with their model that included baryons, cold dark matter, massive neutrinos (hot dark matter), and a cosmological constant. They found that neutrinos can account for no more than 13% of the matter in the universe, and the sum of all three possible neutrino masses is no more than 2.2 eV.

The July 2000 issue of Scientific American includes an article by Chris Llewellyn Smith (pp. 70-78) that provides a useful summary and update on the progress in building the Large Hadron Collider. The LHC should be ready by 2005. In the LHC, two 7-TeV proton beams will collide, yielding a net center-of-mass energy of 14 TeV. The resulting shower of particles will provide the best test to date of the Standard Model of elementary particles and may show evidence of the Higgs boson.

In November 2000, The 27-km (circumference) LEP tunnel at CERN was closed after a run of 11 years. This was done in order to make the tunnel available for the new Large Hadron Collider, which is scheduled to go on line in 2005.

 

Chapter 15

An interesting account in Science magazine (Science 290, 1919 (December 8, 2000) by Martin J. Rees discusses astrophysics and cosmology and how general relativity has played a role in the 20th century, "Piecing Together the Biggest Puzzle of All". It is a very readable account.

 

Chapter 16

Wendy Freedman, an astronmer at the Carnegie Observatories in Pasedena, CA, has written a review article The Hubble Constant and the Expanding Universe, in American Scientist, vol. 91, p. 36 (2003). It is an extremely interesting article and reports that the Hubble constant is now considered to be H 0 = 72 +/- 8, which is consistent with the universe being about 13 billion years old. These numbers are consistent with those quoted in our textbook.

A really useful site on astronomy and recent results can be found at http://itss.raytheon.com/cafe/cafe.html

NASA has a useful site about the universe. See Imagine the Universe

Measurements of the Hubble Constant will continue for years. In 1999 results reported narrowed its value down to 10%. Three results reported in the August 1999 issue of Physics Today (page 19) give values of 71 ± 7 km/(s Mpc), about 60 km/(s Mpc), and 65 ± 7 km/(s Mpc). These results are consistent with the value of 60 – 70 km/(s Mpc) that we reported in the text.

Adaptive optics technology continues to be added to more telescopes allowing astronomers and astrophysicists to see much more detail in ground-based telescopes. See details in a special report called Frontiers in Optics in Science, vol. 286, p. 1504(1999).

A special section on Planetary Systems was published in the October 1 1999 issue of Science, vol. 286, p. 65 (1999). Interesting articles on how planets are born from a swirl of dust, computer simulations of planet formation, expanding environments for life in space, giant planets, and the Galilean satellites of Jupiter are not to be missed!

An interesting article on the results of NASA’s Rossi X-ray Timing Explorer satellite is providing direct measurements of the orbital motion of matter in strongly curved space-times. The laws of motion are predicted in Einstein’s general relativity theory to be qualitatively different from Newtonian mechanics. See the article in Science, vol. 285, p. 1499(1999).

An interesting account in Science magazine (Science 290, 1919 (December 8, 2000) by Martin J. Rees discusses astrophysics and cosmology and how general relativity has played a role in the 20th century, "Piecing Together the Biggest Puzzle of All". It is a very readable account.

The Chandra X-ray Observatory is now operating and has detected numerous x-ray sources from throughout the cosmic background. See Physics Today May 2000 pp. 18-20.

One of the biggest problems in neutrino astronomy has been solved. For several decades scientists have been able to detect only a fraction of the solar neutrinios expected to reach earth from the sun. Finally the mystery has been solved. It has been suspected that neutrinos actually changed from one species to another on the journey to earth and finally an experiment 2 km underground at Canada's Sudbury Neutrino Observatory has been able to prove it. See Arthur B. McDonald, Joshua R. Klein, and David L. Wark, Science 288, 40 (2003). April 2003.