A survey of the empirical aspects, the conceptual basis, and the related fundamental problems, as well as the astrophysical and cosmological applications of the title subject. Specific topics include accelerated particle detectors and the operational meaning of the particle concept in curved space-t

Seeing is life. Seeing is transfonning luminous col- We wish to extend our academic and theoretical ored stimulations and shapes into amental represen- knowledge and also to complete and exchange our tation, structured in space and in time. But seeing is technical and professional experience to prepare also opening onto the world that surrounds us: it is corrective means for the future. thus a means for communicating and learning. Numerous questions have yet to be answered, Jean-Jacques Rousseau, a philosopher worth such as: quoting during the bicentennial of the French Revo- lution of which...

In the mid-sixties, John Robson and Christina Enroth-Cugell, without realizing what they were doing, set off a virtual revolution in the study of the visual system. They were trying to apply the methods of linear systems analysis (which were already being used to describe the optics of the eye and the psychophysical performance of the human visual system) to the properties of retinal ganglion cells in the cat. Their idea was to stimulate the retina with patterns of stripes and to look at the way that the signals from the center and the antagonistic surround of the respective field of each...

The vertebrate retina has a form that is closely and clearly linked to its func tion. Though its fundamental cellular architecture is conserved across verte brates, the retinas of individual species show variations that are also of clear and direct functional utility. Its accessibility, readily identifiable neuronal types, and specialized neuronal connectivity and morphology have made it a model system for researchers interested in the general questions of the genet ic, molecular, and developmental control of cell type and shape. Thus, the questions asked of the retina span virtually every...

My first introduction to the eye came more than three decades ago when my close friend and mentor, the late Professor Isaac C. Michaelson, convinced me that studying the biochemistry of ocular tissues would be a rewarding pursuit. I hastened to explain that I knew nothing about the subject, since relatively few basic biochemical studies on ocular tissues had appeared in the world literature. Professor Michaelson assured me, however, that two books on eye biochemistry had already been written. One of them, a beautiful monograph by Arlington Krause ( 1934) of Johns Hopkins Hospital, is we II...

The human brain contains more than a billion neurons which interconnect to form networks that process, store, and recall sensory information. These neuronal activities are supported by a group of accessory brain cells coll- tively known as neuroglia. Surprisingly, glial cells are ten times more - merous than neurons, and occupy more than half the brain volume (Hyden, 1961). Although long considered a passive, albeit necessary, component of the nervous system, many interesting and unusual functional properties of glial cells are only now being brought to light. As a result, the status of these...