Gerald Holton

Introduction to concepts and theories in physical science

The Description for this book, Introduction to Concepts and Theories in Physical Science, will be forthcoming.

Mach, Einstein, and the Search for Reality

In the history of ideas of our century, there is a chapter that might be entitled ‘The Philosophical Pilgrimage of Albert Einstein’, a pilgrimage from a philosophy of science in which sensationism and empiricism were at the center, to one in which the basis was a rational realism. This essay,* a portion of a more extensive study1, is concerned with Einstein’s gradual philosophical reorientation, particularly as it has become discernible during the work on his largely unpublished scientific correspondence.2

Specific Volumes of Water at High Pressures, Obtained from Ultrasonic‐Propagation Measurements

A computer‐aided procedure has been developed for obtaining specific volumes from measured ultrasonic velocities in any nondispersive medium. Newly measured velocities up to 80°C and 10 000 kg/cm2 have yielded values of specific volumes and a number of thermodynamic coefficients for water over this same range. P. W. Bridgmans measurements of specific volumes in the high‐pressure range showed systematic differences of a few tenths of a percent; the present calculations yield values believed to be good to 0.05% or better for most of the range.

Ultrasonic‐Absorption and Sound‐Speed Data for Nine Liquids at High Pressures

Data for ultrasonic absorption and sound speed are given for water, methyl alcohol, ethyl alcohol, n‐propyl alcohol, n‐butyl alcohol, eugenol, carbon tetrachloride, n‐hexane, and toluene, for pressures ranging up to about 5000 kg/cm2.

On the Origins of the Special Theory of Relativity

Einsteins early work on relativity theory is found to be related to his other work at that time (e.g., in subject matter and style). In addition to this element of internal continuity one finds also—as a key to a new evaluation of the significance of Einsteins contribution—an external continuity with the classic, Newtonian tradition governing restrictions on permissible hypotheses. On the other hand, Einsteins work is shown to have been, in important respects, more independent of other contemporary work in this field than has recently been proposed.These continuities and discontinuities are set forth to make the point that philosophical studies of scientific work should proceed on historically valid ground. Some guiding principles are indicated for dealing with conflicting source materials for such studies.

Limits of scientific inquiry

No wonder you activities are, reading will be always needed. It is not only to fulfil the duties that you need to finish in deadline time. Reading will encourage your mind and thoughts. Of course, reading will greatly develop your experiences about everything. Reading limits of scientific inquiry is also a way as one of the collective books that gives many advantages. The advantages are not only for you, but for the other peoples with those meaningful benefits.

The Project Physics Course, Then and Now

I have been asked to speak today, as the program has it, on “The Project Physics Course, Then and Now.” I do so gladly, but must alert you that it is the story of a roller-coaster ride – up, down, and up again, as you will see. In its first few editions, Project Physics was a nation-wide physics course at the introductory level, chiefly for the 11thand 12th-grade high-school student in the United States, but also used in some colleges. What the audience of this IHPST meeting may want to know most about is no doubt the way in which the design of the course, in addition to physical science itself, used the history and methodologies of science and the interaction of science and society. I will come to that shortly. But this will be better understood if I say first something about the history by which Project Physics came about, and even what its intended future is.

Attenuation of Sound in Suspensions and Emulsions

The absorption of sound in suspensions and emulsions, which can be several orders of magnitude greater than that in the pure substances, usually has been attributed to viscous dissipation processes including relative motion, the relaxing bulk modulus of the suspended material, or scattering. A description of these processes is contained in a more general theoretical treatment, which, in addition, indicates that thermal conduction in the vicinity of the interfaces results in substantial sound attenuation. The theoretical results will be discussed for viscous, compressible, thermal‐conducting media and compared to observed experimental ultrasonic absorption behavior in a number of aqueous emulsions and suspensions. [This research was supported in part by the U. S. Office of Naval Research and the National Institutes of Health.]

Ultrasonic‐Velocity Measurements in Water at Pressures to 10 000 kg/cm2

Measurements of the velocity of ultrasonic pulses in water are presented for pressures up to about 10 000 kg/cm2 and for temperatures up to 80°C. Coefficients obtained from least‐squares polynomial fittings of the data are also given, together with an analysis of the reliability and reproducibility of the experimental results.

Calculation of B/A for Water from Measurements of Ultrasonic Velocity versus Temperature and Pressure to 10 000 kg/cm2

New measurements of the velocity of sound in water over a wide range of temperatures and pressures have been made and are used to calculate the nonlinearity parameter B/A in the temperature range from 0° to 80°C and at pressures to about 10 000 kg/cm2. It is found that, for low temperatures, B/A rises to a broad maximum at about 3000 kg/cm2 and then slowly decreases. At the highest temperatures, B/A decreases very slowly with increasing pressure. At 1 atm pressure, the B/A value for 0°C is the lowest calculated at any temperature and pressure, and B/A increases monotonically with temperature in the range covered. However, at 3000 kg/cm2, the B/A value for 0°C is the largest obtained, and B/A decreases with increasing temperature. The values of B/A range from a low value of 4.08 at 1 atm and 0°C to 6.80 at 3000 kg/cm2 and 0°C. B/A is found to be relatively insensitive to temperature and pressure. The usefulness of B/A measurements as a means of studying the liquid state is discussed.