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Biomedical subjects

L W Alvarez

Publications and source records attributed to L W Alvarez.

5 recordsLinked to original sources

Mass extinctions caused by large bolide impacts.

Evidence indicates that the collisions of Earth and a large piece of Solar System debris such as a meteoroid, asteroid or comet caused the great extinctions of 65 million years ago, leading to the transition from the age of the dinosaurs to the age of the mammals.

Biological Evolution↗

Development of variable- focus lenses and a new refractor.

This paper traces the events that led to the development of the variable-focus lens, the variable-power astigmatic lens, and the principle of remote refraction and "phantom lenses." These developments formed the basis for invention of a new subjective refractor-the Vision Analyzer- whose novel design and rapid operation are described.

Astigmatism↗