Auguste Bravais (; 23 August 1811,

Annonay Annonay (; oc, Anonai) is a commune and largest city in the north of the Ardèche department in the Auvergne-Rhône-Alpes region of southeastern France. It is the most populous commune in the Ardèche department although it is not the capital ...

, Ardèche – 30 March 1863,

Le Chesnay Le Chesnay () is a former commune in the Yvelines department in the Île-de-France region in north-central France. On 1 January 2019, it was merged into the new commune Le Chesnay-Rocquencourt. It is located in the western suburbs of Paris, fro ...

, France) was a French physicist known for his work in

crystallography Crystallography is the experimental science of determining the arrangement of atoms in crystalline solids. Crystallography is a fundamental subject in the fields of materials science and solid-state physics (condensed matter physics). The wo ...

, the conception of

Bravais lattices In geometry and crystallography, a Bravais lattice, named after , is an infinite array of discrete points generated by a set of Translation operator (quantum mechanics)#Discrete Translational Symmetry, discrete translation operations described in t ...

, and the formulation of Bravais law. Bravais also studied

magnetism Magnetism is the class of physical attributes that are mediated by a magnetic field, which refers to the capacity to induce attractive and repulsive phenomena in other entities. Electric currents and the magnetic moments of elementary particle ...

, the northern lights,

meteorology Meteorology is a branch of the atmospheric sciences (which include atmospheric chemistry and physics) with a major focus on weather forecasting. The study of meteorology dates back millennia, though significant progress in meteorology did no ...

, geobotany,

phyllotaxis In botany, phyllotaxis () or phyllotaxy is the arrangement of leaves on a plant stem. Phyllotactic spirals form a distinctive class of patterns in nature. Leaf arrangement The basic arrangements of leaves on a stem are opposite and alternat ...

astronomy Astronomy () is a natural science that studies astronomical object, celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and chronology of the Universe, evolution. Objects of interest ...

, statistics and

hydrography Hydrography is the branch of applied sciences which deals with the measurement and description of the physical features of oceans, seas, coastal areas, lakes and rivers, as well as with the prediction of their change over time, for the primary ...

. He studied at the Collège Stanislas in Paris before joining the

École Polytechnique École may refer to: * an elementary school in the French educational stages normally followed by secondary education establishments (collège and lycée) * École (river), a tributary of the Seine The Seine ( , ) is a river in northern Franc ...

in 1829, where he was a classmate of groundbreaking mathematician

Évariste Galois Évariste Galois (; ; 25 October 1811 – 31 May 1832) was a French mathematician and political activist. While still in his teens, he was able to determine a necessary and sufficient condition for a polynomial to be solvable by radicals, ...

, whom Bravais actually beat in a scholastic mathematics competition. Towards the end of his studies he became a naval officer, and sailed on the ''Finistere'' in 1832 as well as the ''Loiret'' afterwards. He took part in hydrographic work along the

Algeria ) , image_map = Algeria (centered orthographic projection).svg , map_caption = , image_map2 = , capital = Algiers , coordinates = , largest_city = capital , religi ...

n Coast. He participated in the ''Recherche'' expedition and helped the ''Lilloise'' in Spitzbergen and

Lapland Lapland may refer to: Places *Lapland or Sápmi, an ethno-cultural region stretching over northern Fennoscandia (parts of Norway, Sweden, Finland, and Russia) **Lapland (Finland) (''Lappi''/''Lappland''), a Finnish region *** Lapland (former pr ...

. Bravais taught a course in applied mathematics for astronomy in the Faculty of Sciences in

Lyon Lyon,, ; Occitan: ''Lion'', hist. ''Lionés'' also spelled in English as Lyons, is the third-largest city and second-largest metropolitan area of France. It is located at the confluence of the rivers Rhône and Saône, to the northwest of ...

, starting in 1840. He succeeded Victor Le Chevalier in the Chair of Physics at the Ecole Polytechnique from 1845 until 1856 when he was replaced by Henri Hureau de Sénarmont. In 1844 he published a paper on the statistical concept of

correlation In statistics, correlation or dependence is any statistical relationship, whether causal or not, between two random variables or bivariate data. Although in the broadest sense, "correlation" may indicate any type of association, in statisti ...

, and arrived at a definition of the

correlation coefficient A correlation coefficient is a numerical measure of some type of correlation, meaning a statistical relationship between two variables. The variables may be two columns of a given data set of observations, often called a sample, or two componen ...

before

Karl Pearson Karl Pearson (; born Carl Pearson; 27 March 1857 – 27 April 1936) was an English mathematician and biostatistician. He has been credited with establishing the discipline of mathematical statistics. He founded the world's first university st ...

. He is, however, best remembered for his work on Bravais lattices, particularly his 1848 discovery that there are 14 unique lattices in three-dimensional

crystal A crystal or crystalline solid is a solid material whose constituents (such as atoms, molecules, or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions. In addition, macr ...

line systems, correcting the previous scheme, with 15 lattices, conceived by Frankenheim three years before. Bravais published a memoir about crystallography in 1847. A co-founder of the Société météorologique de France, he joined the

French Academy of Sciences The French Academy of Sciences (French: ''Académie des sciences'') is a learned society, founded in 1666 by Louis XIV at the suggestion of Jean-Baptiste Colbert, to encourage and protect the spirit of French scientific research. It was at th ...

in 1854. Bravais also worked on the theory of observational errors, a field in which he is especially known for his 1846 paper "Mathematical analysis on the probability of errors of a point". The mountain Bravaisberget, in Svalbard, is named after Bravais.

References

{{DEFAULTSORT:Bravais, Auguste 1811 births 1863 deaths People from Annonay Members of the French Academy of Sciences French physicists École Polytechnique alumni Collège Stanislas de Paris alumni