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1.
T. James M. Boyd 《Physics in Perspective (PIP)》2012,14(1):4-32
A century ago, George Hartley Bryan (1864–1928) published his classic book, Stability in Aviation. I draw together some strands from events that awakened his interest in the nascent science of aviation, in particular the
stability of flight. Prominent among those who influenced him was Ludwig Boltzmann (1844–1906), who held Bryan in high esteem
for his contributions to thermodynamics and kinetic theory. I argue that the seeds of Bryan’s interest in aviation were sown
at the British Association meeting at Oxford in the summer of 1894, at which Boltzmann was guest of honor. A joint discussion
between Section A (Mathematical and Physical Science) and Section G (Mechanical Science) was devoted to the problems of flight,
during the course of which Boltzmann revealed a hitherto unsuspected enthusiasm for flying. 相似文献
2.
Charles H. Holbrow 《Physics in Perspective (PIP)》2011,13(1):36-57
Horace Richard Crane (1907–2007) was born and educated in California. His childhood was full of activities that helped him
become an outstanding experimental physicist. As a graduate student at the California Institute of Technology (1930–1934),
he had the good fortune to work with Charles C. Lauritsen (1892–1968) just as he introduced accelerator-based nuclear physics
to Caltech. They shared the euphoric excitement of opening up a new field with simple, ingenious apparatus and experiments.
This work prepared Crane for his career at the University of Michigan (1935–1973) where in the 1950s, after making the first
measurement of the electron’s magnetic moment, he devised the g−2 technique and made the first measurement of the anomaly in the electron’s magnetic moment. A man of direct, almost laconic
style, he made lasting contributions to the exposition of physics to the general public and to its teaching in high schools,
community colleges, four-year colleges, and universities. I tell how he became a physicist and describe some of his early
achievements. 相似文献
3.
Benjamin Bederson 《Physics in Perspective (PIP)》2005,7(4):453-472
I discuss the family background and early life of the German theoretical physicist Fritz Reiche (1883–1969) in Berlin; his
higher education at the University of Berlin under Max Planck (1858–1947); his subsequent work at the University of Breslau
with Otto Lummer (1860–1925); his return to Berlin in 1911, where he completed his Habilitation thesis in 1913, married Bertha
Ochs the following year, became a friend of Albert Einstein (1879–1955), and worked during and immediately after the Great
War. In 1921 he was appointed as ordentlicher Professor of Theoretical Physics at the University of Breslau and worked there until he was dismissed in 1933. He spent the academic
year 1934–1935 as a visiting professor at the German University in Prague and then returned to Berlin, where he remained until,
with the crucial help of his friend Rudolf Ladenburg (1882–1952) and vital assistance of the Emergency Committee in Aid of
Displaced Foreign Scholars, he, his wife Bertha, and their daughter Eve were able to emigrate to the United States in 1941
(their son Hans had already emigrated to England in 1939).From 1941–1946 he held appointments at the New School for Social
Research in New York, the City College of New York, and Union College in Schenectady, New York, and then was appointed as
an Adjunct Professor of Physics at New York University, where his contract was renewed year-by-year until his retirement in
1958. 相似文献
4.
Augusto José dos Santos Fitas António Augusto Passos Videira 《Physics in Perspective (PIP)》2007,9(1):4-25
We describe the pioneering attempts made by Ruy Luís Gomes (1905–1984) and other Portuguese physicists to develop a research
and teaching seminar in theoretical physics at the University of Oporto in 1942–1944 under the leadership first of the refugee
Austrian theoretical physicist Guido Beck (1903–1988) and then of the Romanian-French theoretical physicist Alexandre Proca
(1896–1955). These efforts failed, however, owing to lack of sustained financial support from the Portuguese government and
to the political repression of the Salazar regime, which dismissed Gomes and other prominent Portuguese physicists and other
scientists from their university positions. 相似文献
5.
John Crepeau 《Physics in Perspective (PIP)》2009,11(4):357-378
Josef Loschmidt (1821–1895) and Josef Stefan (1835–1893) were eminent scientists in the Institute of Physics at the University
of Vienna during the second half of the nineteenth century but are not well known today, as their legacies have been recognized
differently by the scientific community. Loschmidt first described the structure of the benzene molecule and determined the
size of air molecules, from which the number of molecules per unit volume can easily be determined, yet others received the
credit for these achievements. Stefan posited the fourth-power temperature radiation law, but neither he nor his student Ludwig
Boltzmann (1844–1906) calculated the proportionality constant now known as the Stefan-Boltzmann constant. These are instances
of Stigler’s Law of Eponymy. Besides these achievements, perhaps the greatest unheralded contribution of both Loschmidt and
Stefan was the experimental evidence they provided in support of the emerging kinetic theory of gases. 相似文献
6.
Matthew Trainer 《Physics in Perspective (PIP)》2008,10(2):212-223
In 1905 Lord Kelvin (1824–1907) was awarded the second John Fritz Medal for a lifetime of outstanding achievements in science
and technology. I sketch Kelvin’s life, education, and work in thermodynamics, electrical technology, and instrumentation,
and his role in the laying of the Atlantic cable. I then turn to Kelvin’s four visits to America, in 1876 on the centenary
of the Declaration of Independence of the United States of America; in 1884 when he gave his famous Baltimore Lectures at
The Johns Hopkins University; in 1897 when he visited Niagara Falls for the third time and advised George Westinghouse (1846–1914)
on how to develop its enormous water power for the generation of electricity; and in 1902 when he advised George Eastman (1854–1932)
on the development of the photographic industry.
Written in connection with the Kelvin Centenary Year 2007; see “Celebrating the Life of Lord Kelvin,” University of Glasgow
News Review No. 11 (2007), 4.
Matthew Trainer: Matthew Trainer received his M.Phil. degree in physical sciences at the University of Edinburgh in 1980 and
currently is a laboratory instructor at the University of Glasgow where his research focuses in part on the life and work
of Lord Kelvin. 相似文献
7.
T. D. Ibragimov 《Journal of Applied Spectroscopy》2009,76(5):752-755
We have studied the optical transmission of a small aluminum oxide particles – liquid crystal (4-methoxybenzylidene-4′-butylaniline)
system. We have observed that at room temperature, in the spectrum we observe a transmission band with maximum at 1896 cm–1, which is shifted toward shorter wavelengths on application of a voltage and depends on temperature. The experimental results
are explained by the optical homogeneity of the system in a narrow frequency interval when the refractive indices of the particle
material and the matrix are close, and also by reorientation of the liquid crystal molecules when a voltage is applied. 相似文献
8.
Ursula Pavlish 《Physics in Perspective (PIP)》2011,13(2):189-214
I draw on my interviews in 2005–2007 with Gerson Goldhaber (1924–2010), his wife Judith, and his colleagues at Lawrence Berkeley
National Laboratory. I discuss his childhood, early education, marriage to his first wife Sulamith (1923–1965), and his further
education at the Hebrew University in Jerusalem (1942–1947) and his doctoral research at University of Wisconsin at Madison
(1947–1950). He then was appointed to an instructorship in physics at Columbia University (1950–1953) before accepting a position
in the physics department at the University of California at Berkeley and the Radiation Laboratory (later the Lawrence Berkeley
Laboratory, today the Lawrence Berkeley National Laboratory), where he remained for the rest of his life. He made fundamental
contributions to physics, including to the discovery of the antiproton in 1955, the GGLP effect in 1960, the psi particle
in 1974, and charmed mesons in 1977, and to cosmology, including the discovery of the accelerating universe and dark energy
in 1998. Beginning in the late 1960s, he also took up art, and he and his second wife Judith, whom he married in 1969, later
collaborated in illustrating and writing two popular books. Goldhaber died in Berkeley, California, on July 19, 2010, at the
age of 86. 相似文献
9.
Shigeru Takata 《Journal of statistical physics》2010,140(5):985-1005
A symmetric relation between time-dependent problems described by the linearized Boltzmann equation is obtained for a gas
in a fixed bounded domain. General representations of the total mass, momentum, and energy in the domain, as well as their
fluxes through the boundary, in terms of an appropriate Green function are derived from that relation. Several application
examples are presented. Similarities to the fluctuation–dissipation theorem in the linear response theory and its generalization
to gas systems of arbitrary Knudsen numbers are also discussed. The present paper is an extension of the previous work of
the author (Takata in J. Stat. Phys. 136: 751–784, 2009) to time-dependent problems. 相似文献
10.
Maria Cecilia von Reichenbach 《Physics in Perspective (PIP)》2009,11(3):302-317
Richard Gans (1880–1954) was appointed Professor of Physics and Director of the Institute of Physics of the National University
of La Plata,Argentina, in 1912 and published a series of papers on quantum physics between 1915 and 1918 that marked him as
the first quantum physicist in Latin America. I set Gans’s work within the context of his education and career in Germany
prior to 1912 and his life and work in Argentina until 1925, as well as the foundation of the Institute of Physics of the
National University of La Plata in 1906–1909 and its subsequent development by Emil Bose (1874–1911). I conclude by commenting
on Gans’s life after he returned to Germany in 1925 and then immigrated once again to Argentina in 1947. 相似文献
11.
Christopher M. Graney 《Physics in Perspective (PIP)》2011,13(4):387-400
In 1651 the Italian astronomer and physicist Giovanni Battista Riccioli (1598–1671) published his encyclopedic book, Almagestum novum, in which he presented seventy-seven arguments against the Copernican theory of the movement of the Earth, one of which foresaw
an effect that physicists today attribute to the Coriolis force. Galileo Galilei (1564–1642), Isaac Newton (1642–1727), and
Robert Hooke (1635–1703) investigated this argument, which raises significant questions about the nature of the opposition
to the Copernican theory in the seventeenth century. 相似文献
12.
In this paper nonlocal boundary conditions for the Navier–Stokes equations are derived, starting from the Boltzmann equation
in the limit for the Knudsen number being vanishingly small. In the same spirit of (Lombardo et al. in J. Stat. Phys. 130:69–82,
2008) where a nonlocal Poisson scattering kernel was introduced, a gaussian scattering kernel which models nonlocal interactions
between the gas molecules and the wall boundary is proposed. It is proved to satisfy the global mass conservation and a generalized
reciprocity relation. The asymptotic expansion of the boundary-value problem for the Boltzmann equation, provides, in the
continuum limit, the Navier–Stokes equations associated with a class of nonlocal boundary conditions of the type used in turbulence
modeling. 相似文献
13.
Wolfgang L. Reiter 《Physics in Perspective (PIP)》2007,9(3):357-374
Ludwig Boltzmann (1844–1906) died just over a century ago. In commemoration of his death, I sketch his pioneering contributions
to thermodynamics and statistical mechanics within the context of his often troubled life. 相似文献
14.
In the divertor plasma detachment regime one expects to encounter turbulent collisional neutral gas dynamics. These conditions
are ideally simulated by lattice Boltzmann methods — methods ideal for application on multi-parallel processors. As illustrative
of this method, we specifically show the effect of conductivity in the Rayleigh-Benard convection cells, using an octagonal
velocity lattice.
This work was supported by DoE and a joint U.S-Czech grant. These results were presented at the 6th International Workshop
on Plasma Edge Theory in Fusion Devices, 15–17 September 1997. 相似文献
15.
Yu. K. Zemtsov A. Yu. Sechin A. N. Starostin A. G. Leonov D. I. Chekhov 《JETP Letters》1997,65(11):839-844
The purely thermal infrared emission spectra of a resonance medium (sodium vapor) are investigated experimentally. It is shown
that the emission intensity in the 2–3 μm range at temperatures of 600–1200 K is several orders of magnitude higher than the
intensity obtained from the standard theory of resonance radiation transfer. This phenomenon can be conventionally termed
an “infrared catastrophe.” The form of the recorded spectra and the absolute intensity of the emission in both the infrared
and visible regions of the spectrum are in agreement with the theory developed by Yu. L. Zemtsov and A. M. Starostin, Zh.
éksp. Teor. Fiz. 103, 345 (1993) [JETP 76, 186 (1993)], in which the Boltzmann spectral distribution of the population of the resonance level is proportional to exp(−ħω/T).
Pis’ma Zh. éksp. Teor. Fiz. 65, No. 11, 807–811 (10 June 1997) 相似文献
16.
Robert M. Strain 《Communications in Mathematical Physics》2010,300(2):529-597
In this paper it is shown that unique solutions to the relativistic Boltzmann equation exist for all time and decay with any
polynomial rate towards their steady state relativistic Maxwellian provided that the initial data starts out sufficiently
close in L¥l{L^\infty_\ell}. If the initial data are continuous then so is the corresponding solution. We work in the case of a spatially periodic box.
Conditions on the collision kernel are generic in the sense of Dudyński and Ekiel-Jeżewska (Commun Math Phys 115(4):607–629,
1985); this resolves the open question of global existence for the soft potentials. 相似文献
17.
The Navier–Stokes transport coefficients for binary mixtures of smooth inelastic hard disks or spheres under gravity are determined
from the Boltzmann kinetic theory by application of the Chapman–Enskog method for states near the local homogeneous cooling
state. It is shown that the Navier–Stokes transport coefficients are not affected by the presence of gravity. As in the elastic
case, the transport coefficients of the mixture verify a set of coupled linear integral equations that are approximately solved
by using the leading terms in a Sonine polynomial expansion. The results reported here extend previous calculations (Garzó,
V., Dufty, J.W. in Phys. Fluids 14:1476–1490, 2002) to an arbitrary number of dimensions and provide explicit expressions for the seven Navier–Stokes transport coefficients
in terms of the coefficients of restitution and the masses, composition, and sizes of the constituents of the mixture. In
addition, to check the accuracy of our theory, the inelastic Boltzmann equation is also numerically solved by means of the
direct simulation Monte Carlo method to evaluate the diffusion and shear viscosity coefficients for hard disks. The comparison
shows a good agreement over a wide range of values of the coefficients of restitution and the parameters of the mixture (masses
and sizes). 相似文献
18.
Paul Ehrenfest (1880–1933) received his Ph.D. degree at the University of Vienna in 1904 and moved with his wife and young
daughter to St. Petersburg in 1907, where he remained until he succeeded Hendrik Antoon Lorentz (1853–1928) in the chair of
theoretical physics at the University of Leiden in 1912. Drawing upon Ehrenfest’s correspondence of the period, we first examine
Ehrenfest’s difficult and insecure years in St. Petersburg and then discuss his unsuccessful attempts to obtain a position
elsewhere before he was appointed as Lorentz’s successor in Leiden.
Pim Huijnen is writing a doctoral dissertation in history; the present paper is based upon his Master’s Thesis, “‘Die Grenze
des Pathologischen’: Het leven van fysicus Paul Ehrenfest, 1904–1912,” University of Groningen, 2003. A.J.Kox is Pieter Zeeman
Professor of History of Physics at the University of Amsterdam. 相似文献
19.
A criterion for the propagation of weakly-damped spin waves is obtained on the basis of a detailed analysis of the quantum
collision integral for particles in a paramagnetic polarized Boltzmann gas. It is shown that according to this criterion spin
waves can propagate in classical (nonquantum) gases at temperatures close to room temperature.
Pis’ma Zh. éksp. Teor. Fiz. 67, No. 10, 777–782 (25 May 1998) 相似文献
20.
N. D. Lu Y. Q. Zhou T. G. Shen P. L. Ji J. Sun B. G. Yuan F. C. Yu 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2009,54(3):707-710
The paper investigated a composite photonic crystal patch antenna by using the method of finite difference time domain (FDTD).
The results show that there exists a wave resonance state at 2.635 GHz, where the real part of the permittivity and permeability
are all negative; its refraction index is –1. The effect has largely enhanced the electromagnetic wave’s resonance intensity,
and has improved the localized extent of electromagnetic energy obviously in such photonic crystal structure (PBG), resulting
in a higher antenna gain, a lower return loss, and a better improvement of the antenna’s characteristics. Due to such the
advantages, the use of patch antennas can be extended to such fields as mobile communication, satellite communication, aviation,
etc. 相似文献