Diplom (Master Science) in Theoretical Physics, Ludwig Maximilian
University (LMU), Munich, Germany
Ph.D. in Theoretical Nuclear Physics, LMU
Ph.D. habil. in Theoretical Astrophysics, LMU
Superdense matter. My research
focuses on the theoretical exploration of the properties of strongly
interacting matter at ultra-high densities (10 to 20 times denser than
atomic nuclei) and temperatures (several hundred billion degrees).
Experimentally, the properties of such matter are being probed with the
Relativistic Heavy Ion Collider RHIC at Brookhaven and the Large Hadron
Collider (LHC at Cern). Great advances in our understanding of such
matter are expected from the next generation of heavy-ion collision
experiments at FAIR (Facility for Antiproton and Ion Research at GSI)
and NICA (Nucloton-bases Ion Collider fAcility at JINR). The long sought
after quark gluon plasma (hot QCD matter) was created for the first time
at RHIC in 2000. Since then the RHIC physics program has successfully
measured or bracketed parameters that are of fundamental physical
importance for our understanding of hot QCD (Quantum Chromo Dynamics)
matter.
Neutron stars, quark stars, supernovae
and gamma-ray bursts. Theoretically, it is understood that the
universe was filled with super-dense matter shortly after the Big Bang,
is being created in the final stages of catastrophic stellar events
(core-collapse supernovae, gamma-ray bursts), and exists deep inside the
cores of collapsed stars, know as neutron stars. Neutron stars are
dense, neutron-packed remnants of massive stars that blew apart in
supernova explosions. They are typically about 10 kilometers across and
spin rapidly, often making many hundred rotations per second. Many
neutron stars form radio pulsars, emitting radio waves that appear from
the Earth to pulse on and off like a lighthouse beacon as the star
rotates at very high speeds. Neutron stars in X-ray binaries accrete
material from a companion star and flare to life with tremendous bursts
of X-rays. Depending on mass and rotational frequency, gravity
compresses the matter in the core regions of neutron stars to densities
that are 10 to 20 times higher than the density of ordinary atomic
nuclei. A thimble full of neutron star matter would have a mass of one
billion tons! At such extraordinary densities atoms themselves collapse,
and atomic nuclei are squeezed so tightly together that new fundamental
particles are generated and novel states of matter are created. The most
spectacular phenomena stretch from the creation of novel particles
(hyperons and/or delta particles), to boson condensates, to quark
matter. The interest in the physics and astrophysics of quark matter has
recently received an additional boost from the discovery that quark
matter ought to be a superconductor, which would have very intriguing
consequences for numerous astrophysical phenomena. There is also the
very intriguing theoretical suggestion of E. Witten (Princeton) that
neutron stars may be made up of absolutely stable strange quark matter,
a configuration of matter even more stable than the most stable atomic
nucleus, 56Fe, which, if true, would turn our understanding of neutron
stars upside down. [Read more]