Emanoil Bacaloglu (; – 30 August 1891) was a

Wallachia Wallachia or Walachia (; ro, Țara Românească, lit=The Romanian Land' or 'The Romanian Country, ; archaic: ', Romanian Cyrillic alphabet: ) is a historical and geographical region of Romania. It is situated north of the Lower Danube and so ...

n and

Romania Romania ( ; ro, România ) is a country located at the crossroads of Central Europe, Central, Eastern Europe, Eastern, and Southeast Europe, Southeastern Europe. It borders Bulgaria to the south, Ukraine to the north, Hungary to the west, S ...

mathematician A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems. Mathematicians are concerned with numbers, data, quantity, structure, space, models, and change. History On ...

physicist A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe. Physicists generally are interested in the root or ultimate caus ...

and

chemist A chemist (from Greek ''chēm(ía)'' alchemy; replacing ''chymist'' from Medieval Latin ''alchemist'') is a scientist trained in the study of chemistry. Chemists study the composition of matter and its properties. Chemists carefully describe th ...

. Born in

Bucharest Bucharest ( , ; ro, București ) is the capital and largest city of Romania, as well as its cultural, industrial, and financial centre. It is located in the southeast of the country, on the banks of the Dâmbovița River, less than north of ...

and of

Greek Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a branch of the Indo-European language family. **Proto-Greek language, the assumed last common ancestor ...

origin, he studied physics and mathematics in

Paris Paris () is the capital and most populous city of France, with an estimated population of 2,165,423 residents in 2019 in an area of more than 105 km² (41 sq mi), making it the 30th most densely populated city in the world in 2020. S ...

and

Leipzig Leipzig ( , ; Upper Saxon: ) is the most populous city in the German state of Saxony. Leipzig's population of 605,407 inhabitants (1.1 million in the larger urban zone) as of 2021 places the city as Germany's eighth most populous, as wel ...

, later becoming a professor at the

University of Bucharest The University of Bucharest ( ro, Universitatea din București), commonly known after its abbreviation UB in Romania, is a public university founded in its current form on by a decree of Prince Alexandru Ioan Cuza to convert the former Princel ...

and, in 1879, a member of the Romanian Academy. Considered to be the founder of many scientific and technological fields in Romania (and aiding in the creation of the

Romanian Athenaeum The Romanian Athenaeum ( ro, Ateneul Român) is a concert hall in the center of Bucharest, Romania, and a landmark of the Romanian capital city. Opened in 1888, the ornate, domed, circular building is the city's most prestigious concert hall an ...

), Bacaloglu was also an accomplished scientist. He helped create Romanian-language terminology in his fields and was one of the principal founders of the Society of Physical Sciences in 1890. He was also a participant in the

1848 Wallachian revolution The Wallachian Revolution of 1848 was a Romanian liberal and nationalist uprising in the Principality of Wallachia. Part of the Revolutions of 1848, and closely connected with the unsuccessful revolt in the Principality of Moldavia, it sought t ...

. He is known for the "Bacaloglu

pseudosphere In geometry, a pseudosphere is a surface with constant negative Gaussian curvature. A pseudosphere of radius is a surface in \mathbb^3 having curvature in each point. Its name comes from the analogy with the sphere of radius , which is a surface ...

". This is a

surface of revolution A surface of revolution is a surface in Euclidean space created by rotating a curve (the generatrix) around an axis of rotation. Examples of surfaces of revolution generated by a straight line are cylindrical and conical surfaces depending on ...

for which the "Bacaloglu

curvature In mathematics, curvature is any of several strongly related concepts in geometry. Intuitively, the curvature is the amount by which a curve deviates from being a straight line, or a surface deviates from being a plane. For curves, the canonic ...

" is constant.

Main works

* ''Elemente de fizică'', 2nd ed., București, (1888). * ''Elemente de algebră'', 2nd ed., București, (1870).

References

* Florica Câmpan, "La pseudosphère de Bacaloglu", Acad. Roum. Bull. Sect. Sci. 24 (1943), 96–105.

External links

*
Emanoil Bacaloglu în Galeria personalităților – Muzeul Virtual al Științei și Tehnicii Românești
* *
Emanoil Bacaloglu - Biography.name

at the

Polytechnic University of Bucharest Politehnica University of Bucharest ( ro, Universitatea Politehnica din București) is a technical university in Bucharest, Romania. 200 years of activity have been celebrated lately, as the university was founded in 1818.19th-century Romanian mathematicians Romanian physicists Romanian chemists Titular members of the Romanian Academy People of the Revolutions of 1848 University of Bucharest faculty Scientists from Bucharest 1830 births 1891 deaths Romanian expatriates in France {{chemist-stub