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Alternative approach to the many-body problem

In his doctoral dissertation, Alexander Odriazola proposes a new methodology for exploring the so-called many-body problem that continues to puzzle physicists. It is defined as the study of the effects of interaction between bodies on the behavior of a many-body system.

The Many-Body Problem remains one of the most fascinating and challenging and problems in physics. It is known that there is no universal approach to solve it, but the final method-of-choice is determined by a balanced analysis of the nature of the problem, the required accuracy, and the availability of computational resources. This is precisely what makes the Many-Body Problem such a vast and active area of research.

The main objective of the dissertation is to introduce what we call a scaling approach, not as a method to solve the many-body problem, but as an efficient way to organize the information contained in its solution in order to extract yet more – sometimes non-trivial – information. To this end, we apply the scaling approach to a wide range of systems, from nanostructures (quantum dots) to atoms and atomic ions. We find that many magnitudes follow scaling relations, or in other words, they can be expressed in terms of a single, particular combination of the system main parameters.

“My dissertation demonstrates the functional form of the scaling relations, but I also provide explicit analytical expressions for the scaled quantities. Such expressions are not simple by-products of the approach, but approximations that can be used for estimating relevant quantities with practically no computational cost,” describes Odriazola.

Furthermore, the obtained scaling relations may serve as a starting point for the improvement of more elaborate theories, for example, in the optimization of density functionals within density functional theory.

Public defense of a doctoral dissertation on Friday, 26 January 2018

MSc (Phil) Alexander Odriazola’s doctoral dissertation in the field of physics entitled “Scaling Approaches to Quantum Many-Body Problems” will be publicly examined at the Faculty of Natural Sciences of Tampere University of Technology (TUT) in room S2 in the Sähkötalo building (address: Korkeakoulunkatu 3, Tampere, Finland) at 12 noon on Friday, 26 January 2018.

The opponent will be Professor Irene D’Amico (University of York, UK). Professor Esa Räsänen from the Quantum Control and Dynamics Group at TUT will act as Chairman.

The dissertation is available online at:

Alexander Odriazola comes from Havana, Cuba, and currently lives in a farm in the peaceful Finnish countryside.

Further information: Alexander Odriazola, tel. +358 46 68 3258, (until 03.02.2018)

News submitted by: Sanna Kähkönen
Keywords: science and research, physics