Kolloquium Winter 2015/16 - Physik-Department

2015/16
PhysikKolloquium
Winter
Münchner
Vortragsprogramm mit Abstracts
Beginn der Veranstaltungen ist um 17:15 Uhr, München.
sofern keine besondere Anfangszeit vermerkt ist.
bezeichnet Vorträge im Hörsaal 2 des PhysikSämtliche Vorträge sind öffentlich bei freiem EinDepartments
/ TUM am Forschungsgelände in
tritt. Die Art der Nachsitzung wird in der VeranstalGarching.
Das
Forschungsgelände kann mit der U6
tung bekannt gegeben.
(bis Garching-Forschungszentrum) erreicht werbezeichnet Vorträge im Hörsaal H 030 der den.
Fakultät für Physik / LMU in der Schellingstraÿe 4,
Predicting the evolution of in uenza
tive model of tumor growth and image observation
2015-10-19 that describes the tumor evolution at the macrosInstitut für Theoretische Physik, Universität zu Köln
copic imaging level. Model personalization relies
The human u virus undergoes rapid evolution, on a forward model of the patho-physiological
which is driven by interactions with its host immu- process adapted to organ geometries together
ne system. We describe the evolutionary dynamics with image likelihood functions, and an ef cient
by a tness model based on two molecular proper- Bayesian inference approach. We illustrate the apties of the virus: protein folding stability and binding plication of the tumor growth model in radiation
af nity to human antibodies. This model success- therapy.
fully predicts the evolution of in uenza one year
into the future. Thus, evolutionary analysis transcends its traditional role of reconstructing past Internally Coupled Ears (ICE): the
history. This has important consequences for pu- cool part of sound localization
blic health: evolutionary predictions can inform the Prof. Dr. J. Leo van Hemmen
selection of in uenza vaccine strains. We discuss
2015-11-02
the conditions of predictability and highlight the Physik-Department, Technische Universität München
role of physics in making evolutionary biology a Internally coupled ears, for short ICE, provide
a powerful means of enhancing (in a directionpredictive science.
dependent fashion) the input difference between
left and right ear due to an external sound sourImage-based modeling of tumor
ce. ICE occurs in many animal groups, such as
growth in patients with glioma
frogs, lizards, birds, and crocodilia. Two factors
Prof. Dr. Björn Menze
2015-10-26 play a key role. First, the physical geometry of the
Fakultät für Informatik, Technische Universität München
air- lled cavity connecting the two ear drums. SeGlioma is the most frequent primary brain tumor
cond, the fundamental frequency and hence the
and intensive neuroimaging protocols are used to
elastic properties of the tympana connecting the
evaluate the progression of the disease and the
outside auditory world with the air- lled interior
success of a chosen treatment strategy. This gives
connection. They determine how ICE and hence
rise to large and complex multimodal data sets and
auditory processing work.
extracting diagnostic information across different
clinical imaging modalities and along time poses a
signi cant problem when analysing these data. We
provide an overview of the state of the art in brain
tumor image segmentation, and present a generaProf. Dr. Michael Lässig
The formation of planetary systems
Dr. Leonardo Testi
the cell. Such active gels play a key role in many
2015-11-09 dynamic processes such as cell division and cell
locomotion. Spatial structures in cells can also be
organized with the help of phase separation of different components. Co-existing liquid phases can
provide distinct environments with different chemistry. Spatial patterns of molecular organization
can be formed by the interplay of phase separation
and chemical reactions. I will discuss examples of
cellular systems which make use of such physical principles to generate spatial structures and
dynamic behaviors that play an important role for
cellular function.
ESO, Garching
Our own Solar System formed a little over 4.5 Gyr
ago from a cloud of gas and dust. As the sun was
forming at the centre of the system, planets and
minor bodies of the solar system assembled from
the leftovers of this process. The architecture of our
system and the physical and chemical properties
of its constitutents provide clues of the condition
and prosses at work in that remote era. We also know that planetary systems are very common
around stars in our own galaxy, this implies that the
process of planet formation is a robust one. Nonetheless, the majority of the known exo-planetary
systems have a very different architechture than
our own. The study of stars and planetary systems in formation today in the solar neighborhood
allows us to constrain the physical and chemical
conditions for the formation of planets. In this talk
I will discuss our current understanding of the process of planet formation. I will discuss the current
evidence for the growth of solids in protoplanetary
disks towards the formation of the rocky cores of
planets.
The road to Ly-alpha: A historical
perspective on vacuum
spectroscopy
Dr. Johannes-Geert Hagmann
2015-11-23
Deutsches Museum, München
2013 marked the 100th anniversary of the publication of Niels Bohr's atomic model which for the
rst time successfully explained empirically known
features of hydrogen line spectra. The results of
spectroscopic research on hydrogen of the late
19th and early 20th century have been key elements for the foundation of modern atomic theory.
A precondition for the determination spectroscopic series beyond the visible optical domain has
been the development of novel experimental and
instrumental expertise on the properties of ultraviolet and infrared radiation.
I will discuss the theoretical dif culties we have
in explaining this process and how new observations are providing us with essential data to
solve the long standing `meter size' barrier paradox. Observations with the Atacama Large Millimetre/submillimetre Array are also allowing us to
quantitatively probe the evolution of the volatile
component of protoplanetary disks, at the origin of
planetary atmospheres. I will discuss our current
understanding of the chemical evolution of disks,
at the origin of the different planetary atmospheres
and of complex organic molecules obseved in the
pristine bodies of our own solar system.
This talk reconstructs the pre-history of the discovery of the rst line series of hydrogen (n1 = 1 in
Rydberg's formula), which today bears the name of
its discoverer Theodore Lyman. A particular focus
will be given to the experimental contributions of a
self-trained and mostly self-funded individual, the
amateur physicist Victor Schumann, whose work
Physics of active matter in living
is mostly unknown today. The case of Schumann
cells
sheds light on the question to what extent outsiProf. Dr. Frank Jülicher
2015-11-16 ders to the academic world were able to contribute
Max-Planck-Institut für Physik komplexer Systeme, Dresden
to the progress of physics in the second half of the
Living matter is highly dynamic and organizes in 19th century.
complex patterns and spatial structures. A fundamental problem in biology is to understand how the
interaction of many different molecules and genes
gives rise to a fascinating diversity of patterns and
morphologies. Many dynamic processes in cells
are generated with the help of active processes
such as those mediated by motor molecules. Molecular motors are driven by the chemical energy
of a fuel and generate movements and forces on
molecular scales. Such active processes give rise to unconventional mechanical behaviors and
spontenaous movements of gel-like materials in
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Festkolloquium zu Ehren des 80.
Geburtstags von Prof. Dr. Erich
Sackmann
2015-11-30
airborne telescope SOFIA, have opened a new
window for astrophysical observations at terahertz frequencies revealing a complex interstellar chemistry. Detection of interstellar molecules
relies on the precise knowledge of spectral line
positions from laboratory measurements. In recent years we have studied a number of small
pure carbon-chain molecules, highly unsaturated
carbon-species, oxides, sulfoxides, and stable organic molecules by means of laboratory spectroscopy. Experimental methods to produce and to
study molecules of astrophysical relevance will be
presented.
Gesonderte Anfangszeit: 16:15 h!
Cellular reactions to external forces
Prof. Dr. Rudolf Merkel
Institute of Complex Systems, ICS-7: Biomechanics,
Forschungszentrum Jülich
Throughout the organism almost all tissues experience mechanical strain of sizeable magnitude that
often is important to their organization and development. To unravel the underlying signal sensing
and processing an in vitro model consisting of cells
cultivated on stretchable substrates was introdu- The story of Heisenberg's quantum
ced. Here, I will show how this system can be used mechanics
as quantitative tool to unravel the contributions of
the different cytoskeletal systems and to quan- Prof. Dr. Manfred Kleber
2015-12-14
tify the `mechanosensing potential' of individual
Physik-Department, Technische Universität München
molecules.
Ninety years ago the birth of quantum mechanics took place when Werner Heisenberg subOne hundred years of electri ed
mitted his paper on Quantum-theoretical reinterinterfaces: past, present and future pretation of kinematic and mechanical relations
(Über quantentheoretische Umdeutung kinematiProf. Dr. David Andelman
School of Physics and Astronomy, Tel Aviv University, Israel
scher und mechanischer Beziehungen) to ZeitThe Poisson-Boltzmann theory is a mean- eld de- schrift für Physik. [Z. Phys., 33, 879-893 (1925)].
scription of ionic solutions and charge interfaces, We will show how important the historical context
and it has been instrumental during the last cen- was for an understanding of his work and we will
tury to predict charge distributions and interacti- follow Heisenberg on the narrow path that took him
ons between charged macromolecules. While the from the unsuccessful old quantum mechanics to
electrostatic model of charged uids, on which the light of the new quantum mechanics. We then
the Poisson-Boltzmann description rests, and its discuss Heisenberg's research in the years follostatistical mechanical consequences have been wing his scienti c breakthrough.
scrutinized in great detail, much less is understood about its probable shortcomings when deWISPy dark matter
aling with various aspects of real physical, che2016-01-11
mical and biological systems. After reviewing the Prof. Dr. Jörg Jäckel
Institut für Theoretische Physik, Universität Heidelberg
important results of the Poisson-Boltzmann theoVery light bosons, produced non-thermally in the
ry, I will discuss several modern extensions and
early Universe are an intriguing possibility for the
modi cations as applied to ions in con ned geocold dark matter of the Universe. Particularly intemetries. They include uctuations and correlations
resting candidates are axions, axion-like particles
leading to a surprising attraction of like-charged
and hidden photons. This talk will discuss the
surfaces, the importance of the ion-dipole interaccurrent status of such light dark matter with a
tion in aqueous solutions, and nite size of ions
particular emphasis towards opportunities for its
and other short-range interactions on ionic pro les
detection. We also venture to some more exotic
and surface tension of electrolyte solutions.
candidates and motivations.
•
Quantum dots: Genesis, the
excitonic zoo, and nanodevices
Laboratory investigation of
interstellar molecules
Prof. Dr. Dieter Bimberg
2016-01-18
Institut für Festkörperphysik und Zentrum für Nanophotonik,
Technische Universität Berlin
Prof. Dr. Thomas Giesen
2015-12-07 Universal self-organization and self-ordering ef-
Laborastrophysik, Institut für Physik, Universität Kassel
fects at surfaces of semiconductors lead to the
The advent of new far-infrared telescopes equipformation of coherent zero-dimensional clusters
ped with most sensitive receivers, e.g., the HIFI
called quantum dots (QDs). The electronic and
instrument aboard the Herschel satellite, and the
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optical properties of QDs, being smaller than the
de-Broglie-wavelength in all three directions of
space are closer to those of atoms in a dielectric
cage than of solids. Their delta-function-like energy eigenstates are only twofold (spin) degenerate.
All few particle excitonic states are strongly Coulomb correlated. Their energies depend on shape
and size of the dots, such that positive or negative biexciton binding energies or ne-structure
splitting caused by exchange interaction appear.
nic devices and systems will appear soon. High bit
rate and secure quantum cryptographic systems,
nano- ash memories, or ultra-high speed nanophotonic devices for future optical interconnects,
the Terabus, and 100 160 Gbit/s Ethernet present
some of the rst elds of applications of quantum
dot devices.
Astrochemistry and the rst steps
toward star and planet formation
Prof. Dr. Paola Caselli
Consequently, single QDs present the most practical possible basis of emitters of single polarized
photons (Q-bit emitters) on demand or entangled
photons via the biexciton-exciton cascade for future quantum cryptography and communication
systems. Multiple QD layers, as active materials,
are extremely promising for novel optoelectronic
devices, like edge and surface emitting lasers, ampli ers with properties going far beyond devices
based on higher dimensional systems. Semiconductor nanotechnologies transform presently to
enabling technologies for new economies. It is expected that rst commercialization of nanophoto-
2016-01-25
Max-Planck-Institut für extraterrestrische Physik, Garching
Stars and planetary systems form within dense
(≈ 105 H2 molecules per cc) and cold (≈ 10 K)
fragments of interstellar molecular clouds. Molecules are unique tracers of the physical/chemical
conditions and dynamical evolution of these regions. Thus, astrochemistry is crucial to identify the
ideal molecule and transition to observe. In this
talk I will review results obtained from astrochemical studies of interstellar objects in the earliest
stages of star and planet formation. Links to our
solar systems will also be presented.
Allgemeine Informationen
Das Münchner Physik-Kolloquium ist das Podium der physikalischen Forschung im Münchner Raum. Es wird gemeinsam von den beiden
Universitäten und den entsprechenden MaxPlanck-Instituten veranstaltet. Die Vorträge berichten über aktuelle Themen der Physik und
angrenzender Gebiete und spiegeln den interdisziplinären Charakter der modernen Physik
wider.
Es ist erklärtes Anliegen des Münchner PhysikKolloquiums, die räumliche Trennung der Physik
in die verschiedenen Forschungsstandorte in München und Garching durch eine gemeinsame Veranstaltung zu überbrücken. Dazu soll auch der
alternierende Wechsel des Veranstaltungsorts beitragen.
Veranstaltende Einrichtungen
Max-Planck-Institut für Physik
Föhringer Ring 6, 80805 München
MPI-Koordinator: Dr. F. Simon
Die Darstellung wird möglichst allgemeinverständlich gehalten, um auch physikalisch interessierte
Zuhörer aus dem industriellen oder schulischen
Bereich anzusprechen. Die Vortragenden sind ausgewiesene Fachleute auf dem jeweiligen Gebiet,
zum Teil auch neu nach München berufene Wissenschaftler, die sich in diesem Rahmen einer
breiteren Öffentlichkeit vorstellen wollen. Das Kolloquium stellt insbesondere für die Studenten der
Physik eine einfache Möglichkeit dar, im Laufe
eines Jahres alle wichtigen Arbeitsgebiete der gegenwärtigen physikalischen Forschung kennen zu
lernen.
Technische Universität München
Physik-Department, James-Franck-Straÿe 1,
85748 Garching
TUM-Koordinatoren:
Prof. J. Finley, Prof. K. Krischer, Prof. M. Zacharias
Ludwig-Maximilians-Universität München
Fakultät für Physik, Schellingstraÿe 4,
80799 München
LMU-Koordinatoren:
Prof. B. Ercolano, Prof. J. Lipfert
Aktuelles Programm: http://www.ph.tum.de/kolloquium
nanosystems initiative munich
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