Abstract Taking the integrated viewpoints of causal theory of reference, cognitive science and the notion of correspondence principles from physics, this paper addresses the problems of creativity, the nature of visual imagery and the manner in which science progresses.

I wish to discuss some rather incomplete ideas concerning difficulties that arise in some parts of quantum mechanics. In general there have been no serious difficulties when we are dealing with a finite number of particles, but very essential difficulties arise as soon as we treat a system having an infinite number of degrees of freedom; for example, the theory of holes, which, because of the pair generation, requires an indefinite number of particles; also the Dirac non-relativistic theory of light (...) and the Pauli-Heisenberg relativistic quantum electro-dynamics, these being equivalent to systems consisting of an infinite number of particles. (shrink)

In order to formulate a fundamental quantum field theory of nuclear forces that explains their strength, range, and exchange character, while at the same time accounting for the weak β-decay interaction, Hideki Yukawa introduced a new kind of quantum field. In contrast to the real field of quantum electrodynamics , which he took as his model, Yukawa's U-field was complex, and in contrast to the neutral massless photon of QED, the U-field's ‘heavy’ quanta were charged, carrying the electronic charge . (...) The theory was proposed in November 1934 and published a few months later; however, its advantages were ignored, and for more than two years it went unnoticed, probably because there was no direct experimental evidence for the existence of U-quanta. (shrink)