The Wilhelm and Else-Heraeus Physics School on

**Exploring the limits of the quantum superposition principle: From matter waves to nanomechanical oscillators**

will be held from May 12^{th} to May 17^{th}, 2013 in the Physikzentrum in Bad Honnef, located about 15 km south of Bonn (Germany). It is funded by the Wilhelm and Else Heraeus Foundation.

**Aims of the school**

We are witnessing an increased interest in probing the foundations of quantum mechanics by experiments that delocalize mechanical degrees of freedom over mesoscopic or even macroscopic scales. The systems considered differ widely, from neutrons delocalized on centimeter scale, over the interference of complex molecules and BECs, to attempts of observing quantum motion in mechanical cantilevers and nanobeads. Given the enormous variation in size, mass, complexity, and temperature scales over many orders of magnitude, it may seem surprising that the underlying physics, as well as the required technologies and theoretical approaches share many features. Examples include the requirements for cooling complex systems, as well as the description of effects of decoherence and non‐standard extensions of quantum mechanics. The school aims at bringing the different communities together to learn from each other and to facilitate a fruitful exchange of ideas between the disciplines.

**Topics**

- Ultrafast electron diffraction
- Quantum delocalization in photoionization electrons
- Fundamental physics in neutron interferometry
- Atom interferometry
- BEC interferometry
- Delocalized electrons in mesoscopic structures
- Quantum states of nanomechanical oscillators
- Interference phenomena in phase space
- Measures of macroscopicity
- Towards quantum delocalization of nanospheres
- Spontaneous localization models
- Limits of quantum delocalization in semiclassical gravity
- Coherence in excitonic systems

The organizers invite PhD students, postdocs, and advanced Master students to apply and to present their own work in poster sessions.

The conference language will be English.

The conference fee of EUR 100,- includes accommodation and meals.

Please note that the total number of participants is limited.

Universität Wien | Universitätsring 1 | 1010 Wien | T +43-1-4277-0