Reprint Volume Research Articles

Microseismic interferometry

The past decade witnessed rapid development of the theory of seismic interferometry followed by numerous applications of interferometric approaches in seismic exploration and exploitation. This body of work, partially collected in the “Seismic Interferometry” supplement of Geophysics (2006), SEG's 2008 reprint volume edited by Wapenaar et al., and the “Interferometry Applications” special section of The Leading Edge (2011), conclusively demonstrates that a stack of crosscorrelations of traces recorded by two receivers over sources appropriately distributed in a three-dimensional heterogeneous Earth can retrieve a signal that would be observed at one receiver if another acted as a source of seismic waves. This assertion is applicable to both active-source data (many instructive geometries of this kind are examined by Schuster, 2009) and passive records of ambient noise; examples of the latter, summarized by Snieder and Wapenaar (2010), range from ultrasonics (Weaver and Lobkis, 2001) to global seismology (Shapiro et al., 2005).

The Quantum Hall Effect: Poincaré Seminar (Progress in Mathematical Physics)

The Séminaire Poincaré provides hopefully accessible, accurate and up-to-date reviews of important topics in physics. The seminar usually invites people from both experiment and theory to discuss aspects of the topic. Recent topics, including Entropy (2003), Einstein (2005), and Quantum Decoherence (2005), demonstrate a determination on the part of the organisers to keep the seminar attractive to almost anyone active in physics and to avoid becoming too focused on a specialist area of research. A seminar on the quantum hall effect (QHE) was held in 2004. There were presentations by Klaus von Klitzing (Historical overview), Benoit Doucot and Vincent Pasquier (Introductory Theory), Blaise Jeanneret and Beat Jeckelman (QHE as an electrical resistance standard), Steven Girvin (Introduction to the Fractional QHE) and by Christian Glattli (Tunneling in the FQHE regime). This book is the collection of their contributions. The QHE as a field is already well-served by a small number of excellent books containing original articles by collections of authors and by a reprint volume, so it was not at all clear what a new volume could contribute. Well, this seminar has found something. It concentrates on experimental aspects not so often reviewed and keeps the theory as non-technical as possible. The introductory notes on the theory of electrons in a strong magnetic field give a beautiful explanation of the background theory. In the rush to get onto the technically challenging theory, this material is often assumed part of everyone's background knowledge or it is oversimplified. At the level of a first year graduate student/final year masters student, the chapter takes the reader carefully through projection onto a Landau level, Laughlin's original argument for the quantization of the Hall effect and the link to a topological invariant. Steve Girvin's chapter is at approximately the same level. It covers introductory material on the Laughlin wavefunction and its neutral and charge excitations. The chapter on metrology is a stand-alone article about the use of the QHE in defining absolute standards of measurement. The authors have given an interesting account of how the small deviations from an absolute standard or resistance depend on aspects of the samples, the current distribution, the temperature, edge states as well as contacts. They also explain how the QHE is now used by most metrology institutes to provide a dc reference for the Ohm. The final chapter on tunneling in FQHE systems looks at conductance and shot noise measurements (many of which were made by collaborations including the author). Backscattering in the FQHE by constrictions lead to a non-linear conductance in which the exponent varies as a power of voltage, which (according to theory) is quantized, and in which the shot noise directly measures the charge of the elementary excitation. This chapter is very welcome. It manages to explain what is actually measured and how to think about the implications without including technical theory.

Letters to Language

Letters to Language Eric P. Hamp, Keith Johnson, Edward Flemming, Richard Wright, D. H. Whalen, Harriet S. Magen, Marianne Pouplier, A. Min Kang, and Khalil Iskarous Language accepts letters from readers that briefly and succinctly respond to or comment upon either material published previously in the journal or issues deemed of importance to the field. The editor reserves the right to edit letters as needed. Brief replies from relevant parties are included as warranted. A birthday reception of the LSA August 28, 2004 To the Editor: On the 80th anniversary of the formation of the LSA and within hailing distance still of a new century (it is surely indulging in exaggeration to claim a new millennium) it may be of interest to note an aspect of the reception offered the LSA’s appearance on the scene. An important reflection may be found in the international review Litteris 5.148–59 (1928), though by ‘international’ what is really meant is trans-Atlantic West European (inasmuch as most of our founding fathers, or their Doktorväter, had their post-baccalaureate training and diplomas from those regions). Here the foundation of the LSA (1924), the first four volumes of Language (1925–28), the first three Language monographs (1925–26), the first Language dissertation (1927), and the first LSA Bulletin (1926, ‘Opportunities for advanced work in the US’) were meticulously passed in review. The reviewer, Holger Pedersen, was not inconsiderable. A gigantic Junggrammatiker, who in his youth by the turn of the century had contributed brilliantly and seminally to a half-dozen branches of Indo-European (IE) scholarship (including Celtic, Albanian, Armenian, Slavic, Baltic—his Anatolian and Tocharian came later), his views on traditional subjects and theories carried commanding authority—and have stood the test of time. Yet Pedersen was a perceptive, receptive, progressive yet critical thinker AND worker. His monumental (and still fundamental) two-volume comparative Celtic grammar (Vergleichende Grammatik der keltischen Sprachen, Vandenhoeck & Ruprecht, 1909–13) is by far the first major IE reference work to recognize and use substantively Saussure’s (1878) laryngeal theory (-ies; cf. La 5e déclinaison latine, 1926, and remarks he made on Sturtevant’s work referred to in the following). Note therefore Pedersen’s remarks on Sapir, especially in relation to the much-neglected Baudouin de Courtenay (153, ‘Sound patterns…’); on Bloomfield, yet without rancour (150ff.); and on Sturtevant (156–57; closer to home for Pedersen, but still very avant-garde in 1928). Finally, observe Pedersen’s persistent attention to data and observation along with theory; cf. in this connection his indispensable and almost universally neglected fieldwork and observation in Albanian (1890s–1900) and pioneering fieldwork in Aran (Connaught) Irish. Note also changes, from our point of view, such as the perceived role of the innovative Linguistic Institute; on this matter, one might compare portions of my remarks as chairman of an LSA committee (1962–1964) in a report, ‘Survey of the state and future of the Linguistic Institute’ (LSA Bulletin 38.39–91, 1965, and note also p. 20, §10 and p. 21, §6 (and p. 20, §3) of the same Bulletin, published as Part 2 of a Supplement to Language 41.3). It would be impudent of me to read more closely for you this master’s words on the occasion. But we see here already a brisk and promising trans-Atlantic conversation. Eric P. Hamp University of Chicago [End Page 645] Editor’s reply Such historical perspectives are always welcome. More on Pedersen, elected an honorary member of the LSA in 1930, can be found in the ‘Notes’ of Language 30.194 (1954), where Bernard Bloch records his death on Sunday, October 25, 1953. Details on Pedersen’s biography and bibliography are contained in Carol Henriksen’s entry in Lexicon grammaticorum (ed. by H. Stammerjohann, Niemeyer, 1996, p. 710) and in Henning Andersen’s in The encyclopedia of language and linguistics (ed. by R. E. Asher and J. M. Y. Simpson, Pergamon, 1994, vol. 6, pp. 2997–98). Pedersen’s important contributions to Armenian studies are given an appreciation by Rüdiger Schmitt in his ‘Einführung’ leading off the reprint volume Holger Pedersen: Kleine Schriften zum Armenischen (Olms, 1982...

Resource Letter Q-1: Quarks

Quarks as fundamental constituents of hadrons play a central role in elementary particle physics. We give an annotated bibliography of references to quarks and related topics in elementary particle physics, as well as to the role of quarks in areas outside elementary particle physics, such as nuclear physics, and astrophysics and cosmology. We label references E (elementary), I (intermediate), and A (advanced) to guide the reader. Articles selected for incorporation in a reprint volume (to be published separately by the American Association of Physics Teachers) are indicated by an an asterisk. A short list of particularly helpful elementary and intermediate references is indicated by a star.

Resource Letter PNAR-1: Physics and the nuclear arms race

This collection of article and book references was assembled to help physicists understand and teach about the nuclear arms race. Both technical and political aspects are covered. Entries are therefore marked as elementary for the layman (E), intermediate for college freshman (I), and advanced for the college senior or graduate student (A) for both the technical (t) and the social (s) aspects. Articles or books which are excerpted in a reprint volume (to be published separately by the American Association of Physics Teachers) are marked with an asterisk (*).

Resource letter SH-1: superfluid helium

The resource letter covers the general subject of superfluid helium and treats 3He and 3He–4He mixtures as well as 4He. No effort has been made to include the fascinating experiments on either solid helium or the equally fascinating work on adsorbed helium where the helium coverage is below that necessary for superfluidity. An earlier resource letter by C. T. Lane [Am. J. Phys. 35, 367 (1967)] may be consulted for additional comments on some of the cited earlier manuscripts, but the present work is self-contained and may be used independently. Many high-quality research reports have not been cited here. Rather, the author has tried in most cases to include works particularly readable or relevant. There is a relatively heavy emphasis on experimental references. The primary reason is that these works tend to be more generally readable. No doubt some works that might have been included, have not, and for this the author takes responsibility with apology. Articles selected for incorporation in a reprint volume (to be published separately by the American Association of Physics Teachers) are marked with an asterisk(*). Following each referenced work the general level of difficulty is indicated by E, I, or A for elementary, intermediate, or advanced.

Resource letter SP-2: Symmetry and group theory in physics

The author has selected material relevant to symmetry and group theory in physics. Entries are marked E (elementary), I (intermediate), and A (advanced) to designate their level. Articles selected for incorporation in a reprint volume (to be published seperately by the American Association of Physics Teachers) are marked with an asterisk().

Resource letter NP-1: New particles

The growth in the number of ’’elementary’’ particles since the discovery of the J/ψ in November of 1974 is reviewed. An attempt is made to combine references to initial discoveries, to reviews of theory and experiment, and to elementary discussions in a way that may be useful at a wide variety of levels. Accordingly references are marked E (Elementary), I (intermediate), and A (advanced). Articles selected for incorporation in a reprint volume (to be published separately by the American Association of Physics Teachers) are marked (‡). For a shorter list of particularly helpful elementary and intermediate references, the reader may consult those marked with an asterisk (*).