Graduiertenkolleg Quantum Fields and Strongly Interacting Matter - News

[Studierende Physik] Einladung zum Physikalischen Kolloquium 27.05.2013 ( 23.05.13 )
Per E-Mail eingestellt von reimann@physik.uni-bielefeld.de:

Liebe Studierende der Physik,

hiermit lade ich Sie recht herzlich zum Physikalischen Kolloquium ein:

Prof. Dr. Hartmut Abele, Atominstitut, TU Wien

The Quantum Bouncing Ball and Gravity Tests with a Quantum Interference

27.05.2013, 16:15, Hoersaal 6

Newton’s Law of Gravity is considered valid from sub-millimetre distances up to inter-galactic space, but fails to describe important features of cosmology like the accelerating expansion component of our universe. While the most straightforward candidate for such a component is Einstein’s cosmological constant [2], a plausible alternative is dynamical vacuum energy, or ”quintessence”, changing over time. Although it is traditional to neglect (or set to zero) the couplings of this light scalar to the standard model, it is natural for a scalar quintessence field to evolve on cosmological time scales today while having couplings to matter, as expected from string theory. Hence the presence of such a field would provide energy changes to Newton’s gravity potential of the earth at short distances invisible to electromagnetic interactions.
We present a novel direct search strategy with neutrons based on Rabi-spectroscopy of quantum transitions in the gravity potential of the earth. The sensitivity for deviations on Newton’s gravity law is right now E = 10-14 eV, providing a severe restriction on quintessence fields and on any possible new interactions on that level of accuracy. If some undiscovered dark matter or dark energy particles interact with a neutron, this should result in a measurable energy shift of the observed quantum states. In the case of some dark energy scenarios with a coupling to matter, the experiment has the potential to find or exclude these hypothetical particles in full parameter space.

Viele Gruesse,

Peter Reimann

http://www2.physik.uni-bielefeld.de/veranstaltungen.html

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Peter Reimann

Fakultaet fuer Physik +49-521-106 6202 phone
Universitaet Bielefeld +49-521-106 6455 fax
Postfach 100131 reimann@uni-bielefeld.de
D-33501 Bielefeld
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

--
Information zum Mailverteiler: Alle Studierenden der Fakultaet fuer Physik
[Studierende Physik] Einladung zum Physikalischen Kolloquium 13.05.2013 ( 10.05.13 )
Per E-Mail eingestellt von reimann@physik.uni-bielefeld.de:

Liebe Studierende der Physik,

hiermit lade ich Sie recht herzlich zum Physikalischen Kolloquium ein:

Prof. Silas Beane, Univ. of New Hampshire and Univ. of Bonn

Aspects of 21st Century Nuclear Physics

13.05.2013, 16:15, Hoersaal 6

Over the last several decades, theoretical nuclear physics has been evolving from a very-successful phenomenology of the
properties of nuclei, toward the ultimate goal of a first-principles derivation of the properties of the visible matter in the
Universe from the known underlying theories of Quantum Chromodynamics and Electrodynamics. After a brief motivational
introduction, I will present some of the most recent calculations of the simplest nuclear and hypernuclear systems which make
use of both lattice QCD and effective field theory methods. These include the first physical predictions of baryon-baryon
scattering, the spectrum of the light nuclei and hypernuclei, as well as very recent work which is beginning to illuminate
the nuclear fine-tunings that in some sense define the Universe that we live in.

Viele Gruesse,

Peter Reimann

http://www2.physik.uni-bielefeld.de/veranstaltungen.html

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Peter Reimann

Fakultaet fuer Physik +49-521-106 6202 phone
Universitaet Bielefeld +49-521-106 6455 fax
Postfach 100131 reimann@uni-bielefeld.de
D-33501 Bielefeld
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

--
Information zum Mailverteiler: Alle Studierenden der Fakultaet fuer Physik