Robert H. Dicke

Robert Henry Dicke (May 6, 1916 – March 4, 1997) was an American physicist, who made important contributions to the fields of astrophysics, atomic physics, cosmology and gravity.

Quotes

• Is the earth affected by its cosmological setting in the universe? It is to be presumed that the solar system was molded at its birth by galactic conditions which in turn reflected the primordial chaos of the primitive galaxy. However, we are not concerned here with questions of this type, interesting though they are, but rather with a problem of even grander proportions: Is there an effect upon the earth, here and now, of the distribution of matter in the universe? As the universe expands, as distant matter moves away from us, are there effects upon the earth of this changing distribution of matter?
  • (November 9, 1962)"The Earth and Cosmology: The earth may be affected by the distant matter of the universe through a long-range interaction". Science 138 (3541): 653-664. DOI:10.1126/science.138.3541.653.

• A pinhole camera for which the entrance area, covered with a very large number of randomly distributed pinholes, is 50 per cent open is shown to be a very effective way of forming images of a complex of X-ray stars. A simple statistical trick is used to reduce the multitudinous overlapping images to a single image. Less than forty detected photons are needed to form an image of a single star.
  • (August 1968)"Scatter-Hole Cameras for X-Rays and Gamma Rays". The Astrophysical Journal. DOI:10.1086/180230.

• In Heisenberg's famous discussion of the measurement of a particle's position using a microscope, the momentum transferred to the particle by the scattered photon makse the particle's momentum uncertain. It is shown that momentum is also transferred when the lack of a scattered photon is used to discover that the particle is absent from the field of view of the microscope (i.e., located outside the light beam). This apparent paradox, a transfer of momentum and/or energy to a missing particle by a light beam (without the scattering of a photon), is discused and "resolved" using quantum measurement theory.
  • (1981). "Interaction-free quantum measurements: A paradox". American Journal of Physics 49 (10): 925–930.

• I have long believed that an experimentalist should not be unduly inhibited by theoretical untidyness. If he insists in having every last theoretical T crossed before he starts his research the chances are that he will never do a significant experiment. And the more significant and fundamental the experiment the more theoretical uncertainty may be tolerated. By contrast, the more important and difficult the experiment the more that experimental care is warranted. There is no point in attempting a half-hearted experiment with an inadequate apparatus.
  • as quoted by W. Happer, P. J. E. Peebles, and D. T. Wilkinson. Biographical Memoirs, Robert Henry Dicke May 6, 1916 — March 4, 1997.