Research
His discoveries and mathematical deductions, building on experimental work by Thomas Young, extended the wave theory of light to a large class of optical phenomena. In 1817, Young had proposed a small transverse component to light, while yet retaining a far larger longitudinal component. Fresnel, by the year 1821, was able to show via mathematical methods that polarization could be explained only if light was entirely transverse, with no longitudinal vibration whatsoever.
He proposed the aether drag hypothesis to explain a lack of variation in astronomical observations.
His use of two plane mirrors of metal, forming with each other an angle of nearly 180°, allowed him to avoid the diffraction effects caused (by the apertures) in the experiment of F. M. Grimaldi on interference. This allowed him to conclusively account for the phenomenon of interference in accordance with the wave theory.
With François Arago he studied the laws of the interference of polarized rays. He obtained circularly polarized light by means of a rhombus of glass, known as a Fresnel rhomb, having obtuse angles of 126° and acute angles of 54°.
Read more about this topic: Augustin-Jean Fresnel
Famous quotes containing the word research:
“The working woman may be quick to see any problems with children as her fault because she isnt as available to them. However, the fact that she is employed is rarely central to the conflict. And overall, studies show, being employed doesnt have negative effects on children; carefully done research consistently makes this clear.”
—Grace Baruch (20th century)
“... research is never completed ... Around the corner lurks another possibility of interview, another book to read, a courthouse to explore, a document to verify.”
—Catherine Drinker Bowen (18971973)
“The great question that has never been answered, and which I have not yet been able to answer, despite my thirty years of research into the feminine soul, is What does a woman want? [Was will das Weib?]”
—Sigmund Freud (18561939)