# Quantum fishes

String theory and the search for a theory of everything

Munich, 11/09/2011

Besides the one in which we live, there may be many parallel universes out there. Indeed, in the context of string theory, this possibility arises quite naturally. Unlike the so-called Standard Model of Particle Physics, in which the basic building blocks of matter are assumed to be point-like elementary particles, string theory postulates that they are one-dimensional energy threads that vibrate at specific frequencies. String theory offers a means to reconcile the theory of general relativity with quantum theory, and provides a unified framework that can account for all of the known fundamental forces that hold our universe together. It is thus regarded as the best hope that physicists have of coming up with a so-called ‘theory of everything’. But it implies that the observable universe might well be just a tiny bubble in a far more extensive structure, a multiverse. In his new book “Quantenfische” (“Quantum Fishes: String Theory and the Search for a Theory of Everything”), theoretical physicist Dieter Lüst, Professor of Mathematical Physics and String Theory at LMU, illustrates the concept underlying string theory with the help of a fairy tale. One day the fish in a small pond discover that everything in the pond, including themselves, consists of elementary building blocks. Naturally enough, they call these “quantum fishes”. They go on to investigate the implications of this discovery and, after much further research, they realize that many other ponds exist in addition to their own. As quantum fishes, they can leave their universe behind and explore a multiverse, a cosmos with a myriad of possible universes – in which the conditions and physical laws differ from those “back home”. Taking his cues from the quantum fishes, Lüst sets out to describe our present understanding of the cosmos. In particular, he considers whether or not the laws of nature are uniquely determined, and marshals the arguments that support the existence of a multiverse. “String theory proposes the following solution to the problem: The laws of physics are not uniquely determined, but they are constrained in a fashion that can be very precisely defined and explained,” he says. (göd/PH)

**Publication:**

Quantenfische. Die Stringtheorie und die Suche nach der Weltformel

Dieter Lüst

C.H. Beck Verlag 2011. 381 pages

ISBN 978-3-406-62285-4

**Contact:**

Professor Dr. Dieter Lüst

Mathematical Physics and String Theory

Tel.: +49 89 2180-4372

Email: dieter.luest@physik.uni-muenchen.de

**Useful Links:**

- CAS Research Focus: String Theory in Context
- Conversation with Prof. Lüst on String Theory (Einsichten 2008)