Francesco Maria Grimaldi (2 April 1618 – 28 December 1663) was an Italian
Jesuit
The Society of Jesus (; abbreviation: S.J. or SJ), also known as the Jesuit Order or the Jesuits ( ; ), is a religious order (Catholic), religious order of clerics regular of pontifical right for men in the Catholic Church headquartered in Rom ...
priest,
mathematician and
physicist who taught at the
Jesuit
The Society of Jesus (; abbreviation: S.J. or SJ), also known as the Jesuit Order or the Jesuits ( ; ), is a religious order (Catholic), religious order of clerics regular of pontifical right for men in the Catholic Church headquartered in Rom ...
college in
Bologna. He was born in Bologna to Paride Grimaldi and Anna Cattani.
Work
Between 1640 and 1650, working with
Riccioli, he investigated the
free fall of objects, confirming that the distance of fall was proportional to the square of the time taken. Grimaldi and Riccioli also made a calculation of
gravity at the Earth's surface by recording the
oscillations of an accurate
pendulum.
In
astronomy, he built and used instruments to measure lunar mountains as well as the height of clouds, and drew an accurate map or, ''
selenograph'', which was published by Riccioli and now adorns the entrance to the
National Air and Space Museum in Washington D.C.
He discovered and was the first to make accurate observations on the
diffraction of
light
Light, visible light, or visible radiation is electromagnetic radiation that can be visual perception, perceived by the human eye. Visible light spans the visible spectrum and is usually defined as having wavelengths in the range of 400– ...
and coined the word 'diffraction'. In his book ''Physico-Mathesis de Lumine, Coloribus et Iride'' (1665), he stated the theory of the reconstitution of sunlight from refracted coloured light. (There is a far-fetched account that
Leonardo da Vinci had earlier noted the effect.)
Through experimentation he was able to demonstrate that the observed passage of light could not be reconciled with the idea that it moved in a rectilinear path. Rather, the light that passed through the hole took on the shape of a cone. Later physicists used his work as evidence that light was a wave, significantly, Dutch mathematician
Christiaan Huygens. He also discovered what are known as diffraction bands.
The crater
Grimaldi on the
Moon
The Moon is Earth's only natural satellite. It Orbit of the Moon, orbits around Earth at Lunar distance, an average distance of (; about 30 times Earth diameter, Earth's diameter). The Moon rotation, rotates, with a rotation period (lunar ...
is named after him.
Publications
He only published one work:
*
The work is mainly remembered for being the first report of diffraction. In the work, he was mainly concerned with two questions:
# Is light a substance or an
accident oughly the same as "property"
# What is the relation between light and color?
He argued that light is probably a subtle fluid (thus a substance), though it might still be an accident (as Aristotelians believed). He also argued that color is associated with undulations of the subtle fluid.
See also
*
List of Jesuit scientists
*
List of Roman Catholic scientist-clerics
References
External links
*
* Grimaldi's (1665
''Physico-mathesis de lumine'' - digital facsimile from the
Linda Hall Library
{{DEFAULTSORT:Grimaldi, Francesco Maria
1618 births
1663 deaths
17th-century Italian Jesuits
17th-century Italian mathematicians
17th-century Italian physicists
Selenographers
Jesuit scientists