## People with a strong Berlin connection - D

Marlene DietrichBorn 1901 in Schönberg, in Sedan Strasse (now Leber Strasse). Her proper name was Maria Magdalena, which she elided to form Marlene. She appeared in Deutschland's first talking filmThe Blue Angel, in 1929. Soon after, she left for Hollywood with von Sternberg. She actively opposed Nazism and met resentment when she returned to Berlin in 1960 - she never returned to Deutschland again.DimitrioffJohann Peter Gustav Lejeune DirichletProfessor of Mathematics at Berlin University from 1828 to 1855. His appointment as a University teacher in Deutschland was controversial because he did not actually possess a doctorate (and also could not speak Latin which was also apparently a requirement). He was nevertheless awarded an honorary doctorate by Köln University, which allowed him to pursue a career as an academic, although obviously not without controversy.Soon aftrer moving to Berlin, he married Rebecca Mendelssohn, sister of the composer Felix.

Among his pupils at Berlin was Kronecker.

In 1855, he took over Gauss's post of Professor in Göttingen. He apparently tried to use his appointment in Göttingen as a lever to try and get improved conditions for himself in Berlin - something that appears to have been only successful after he had committed himself irrevocably to the job in Göttingen.

His work involved :-

- a paper on Fermat's Last Theorem where he showed its validity for n=5 (before coming to Berlin) and for n=14 (1832) : it already been proved for the case n=3 (Euler) and n=4 (Fermat) and was proved for n=7 by Lamé in 1839.
- Analytic Number Theory. In 1863, he published a book on this subject,
Vorlesungen über Zahlentheorie.- The equilibrium of systems, and potential theory as applied to Mechanics.
- Produced an improved derivation of laplace's proof of the stability of the Solar System.
- Became the first person to integrate the hydrodynamic equations exactly.
- Improved the rigor of previous work on Fourier Series by Poisson and Cauchy.

Alfred Döblin, born in Stettin but grew up in Berlin. Qualified as a doctor (psychiatry and neurology) and from 1911 practised in Berlin Lichtenberg. As a Jew and socialist, he left Deutschland in 1933. Returned to Deutschland after the war, but in 1951 settled in Paris. His best-known novelBerlin Alexanderplatzappeared in 1929. HisNovember 1918describes the situation in immediate post-war Berlin.

Rudi Dutschke