Balthazar DE VAULCHIER

PhD Student

Research group: String Theory  

Thesis: "String theory and effective theory"
Advisor : Hervé Partouche

Research

String theory, supergravity, compactification, effective theory

String theory is a quantum and unified theory of fundamental interactions, including gravity. Sometimes, a complete description of the spectrum is needed to solve the problems, while other situations only need the low-energy states of the so-called "effective" theory. The goal will be to use one approach or the other, for example in the case of Hagedorn instability, where a tachyon is present in the spectrum of string theory and induce a phase transition that can be studied through the effective theory. Another example would be to study the mechanisms of compactification in order to determine the the parameters of the theory.

Publications

Partouche H, Toumbas N, de Vaulchier B.
Wavefunction of the universe: Reparametrization invariance and field redefinitions of the minisuperspace path integral.
Nuclear Physics B. 2021;973:115600.
DOI: 10.1016/j.nuclphysb.2021.115600.

Partouche H, de Vaulchier B.
Phase transition at high supersymmetry breaking scale in heterotic string theory.
International Journal of Modern Physics A. 2021:2141001.
DOI: 10.1142/S0217751X21410013.

Kehagias A, Partouche P, de Vaulchier B.
Induced Einstein gravity from infinite towers of states.
Nuclear Physics B. 2021;964:115312.
DOI: 10.1016/j.nuclphysb.2021.115312.

Partouche H, de Vaulchier B.
Heterotic orbifolds, reduced rank and S O (2 n + 1) characters.
International Journal of Modern Physics A. 2020;35(24):2050132.
DOI: 10.1142/S0217751X20501328.

Partouche H, de Vaulchier B.
Hagedorn-like transition at high supersymmetry breaking scale.
Journal of High Energy Physics. 2019(8):155.
DOI: 10.1007/JHEP08(2019)155.

Partouche H, de Vaulchier B.
Induced cosmological and Newton constants from towers of states.
2019 Corfu Summer Institute "School and Workshops on Elementary Particle Physics and Gravity", CORFU 2019, 31 August 2019 - 25 September 2019.
Proceedings of Science, Volume 376, 2019, Article number 118.

Partouche H, de Vaulchier B.
Phase Transitions at High Supersymmetry Breaking Scale in String Theory.
13th International Workshop on Lie Theory and Its Applications in Physics, LT 2019; Varna; Bulgaria; 17 June 2019 through 23 June 2019; Code 250319.
Springer Proceedings in Mathematics and Statistics. 2019;335:265-274.
DOI: 10.1007/978-981-15-7775-8_17