Konstantin Wiegandt, physicist
He is working on his PhD thesis at the Humboldt University in the field of the AdS/CFT correspondence
Konstantin Wiegandt was born in Hamburg in 1981 and grew up in Ahrensburg near Hamburg. After the first year of his studies in Hamburg, he took part in a 1-year exchange program of the Deutsch-Französische Hochschule (German-French University) to receive a German, French and Luxembourgian pre-degree. In this period his prior interest in mathematics and theoretical physics was further stengthened. After his pre-degree he changed to the Humboldt University Berlin where he continued his studies for one year.
In another year abroad at the École Normale Supérieur (ENS) in Paris, he specialized in theoretical elementary particle physics and then returned to Humboldt University. There he wrote his diploma thesis in the group quantum field theory and string theory of Professor Jan Plefka and worked in the field of „string theory“.
On 7th of July 2009, Konstantin Wiegandt was awarded the price „Physik-Studienpreis der Wilhelm und Else Heraeus Stiftung“ in tribute of his university achievements. In his speech at the ceremony, he pointed out the outstanding quality of theoretical lectures at Humboldt University. He mentioned that the Humboldt University could not compete with the ENS concerning the quantity of lectures offered in theory of elementary particle physics, but instead they had a very high quality.
Besides his studies, he worked on a project of the „Studienkollegs zu Berlin“ (a cooperation of the German National Academic Foundation, the Hertie Foundation and the Berlin-Brandenburg Academy of Sciences) about the problem of „undocumented migrants in Europe“. Furthermore he is interested in internet-programming and renewable energies and runs the webpage www.windjournal.de in his spare time.
His research topics
String theory describes all elementary particles not as being pointlike, but rather as one-dimensionally extended objects called „strings“. These can be imagined just as the strings of a violine whose vibrational modes create different sounds. The vibrational excitations of the string represent different elementary particles. An interesting feature of string theory is that it requires more than 3 space dimensions for a consistent formulation.
In his diploma thesis, Konstantin Wiegandt worked on string theory in a special 10-dimensional background space-time, the AdS5xS5, which consists of the 5-dimensional Anti-de-Sitter space and – at each point – possesses additionally the geometry of a 5-dimensional sphere.
Meanwhile Konstantin Wiegandt is working on his PhD thesis at the Humboldt University in Berlin-Adlershof in the group of Prof. Jan Plefka in the field of the so-called AdS/CFT correspondence, which connects the quantum field theoretical formulation of elementary particle physics with string theory in AdS5xS5.
For the time being, he concentrates on aspects of quantum field theory, the most successful theory for the description of the microscopic world. The quantum field theory that is studied in this case „lives“ on the boundary of the Anti-de-Sitter space in which the string theory “lives”. The geometry on this boundary is similar to the 4-dimensional space-time we live in.
What is fascinating about the AdS/CFT correspondence is that the same physical effects can be calculated in string theory as well as with usual quantum field theoretical methods. If the correspondence is correct, it can lead to significant simplifications in both theories, since some problems which are horribly complicated in one of the theories are simple to solve in the other theory. It should be mentioned though that there is no direct proof of the correspondence yet.
In the figure the 4-dimensional version AdS2xS2 consisting of a 2-dimensional Anti-de Sitter space, which can be imagined as a hyperboloid and a 2-sphere, i.e. the usual surface of a ball, is illustrated.