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נובמבר 24, 2014
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Date:23ראשוןנובמבר 2014הרצאה
TBA
More information שעה 11:00מיקום בניין משפחת זוסמןמרצה Gretchen Keppel-Aleks
Atmospheric, Oceanic and Space Sciencesמארגן המחלקה למדעי כדור הארץ וכוכבי הלכתצרו קשר -
Date:23ראשוןנובמבר 2014הרצאה
Unraveling and eliminating dissipation mechanisms in contacts of polymer-bearing surfaces
More information שעה 11:00מיקום בניין פרלמן למדעי הכימיהמרצה Dr. Sissi de Beer
1Jülich Supercomputer Centre, Institute for Advanced Simulation, FZ Jülich, Jülich, Germany 2Materials Science and Technology of Polymers and the Mesa+ Institute, University of Twente, the Netherlandsמארגן המחלקה לכימיה מולקולרית ולמדע חומריםצרו קשר פרטים נוספים Show full text description of Polymer brushes are well known to lubricate high-pressure co...» Polymer brushes are well known to lubricate high-pressure contacts, while they can sustain high normal loads and maintain low friction at the interface. Depending on the contact-geometry, direction of motion and brush characteristics, different dissipation channels dominate the friction forces. I will discuss the relative importance of the dissipation channels for realistic, rough contacts and show via molecular dynamics simulations and atomic force microscopy measurements that, by using an asymmetric contact of two immiscible polymer brush systems, interdigitation can be eliminated. For such immiscible polymer brush systems, we find that friction upon sliding is a few orders of magnitude lower than for symmetric miscible contacts. Moreover, wear of the coating is strongly reduced.
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Date:23ראשוןנובמבר 2014הרצאה
Proteasomes as substrate trappers
More information שעה 13:00מיקום בניין ארתור ורושל בלפר למחקר ביורפואימרצה Asaf Biran
Yosef Shaul's group, Dept. of Molecular Genetics, WISמארגן המחלקה לגנטיקה מולקולריתצרו קשר -
Date:23ראשוןנובמבר 2014הרצאה
Collective excitations of hydrodynamically coupled driven colloidal particles
More information שעה 14:15מיקום בניין הפיסיקה ע"ש עדנה וק.ב. וייסמןמרצה Yael Roichman
Tel Aviv Universityמארגן המחלקה לפיסיקה של מערכות מורכבותצרו קשר תקציר Show full text abstract about A single colloidal particle trapped in an optical vortex exp...» A single colloidal particle trapped in an optical vortex experiences two optical forces: a gradient force confining it to motion along a finite width ring of light, and radiation pressure driving it along the perimeter of the ring. As a result, the particle rotates, at constant angular velocity with thermal fluctuations. When a second particle is introduces to the vortex trap the two particles pair due to a pseudo-potential caused by the interplay between hydrodynamic interactions and the curvature of the particles’ trajectory. We study the collective excitations of many colloidal particles driven in an optical vortex trap. We find that even though the system is overdamped, hydrodynamic interactions due to driving give rise to non-decaying excitations with characteristic dispersion relations. The collective excitations of the colloidal ring reflect fluctuations of particle pairs rather than those of single particles. -
Date:24שנינובמבר 2014הרצאה
"Lineage-specific processes of genome diversification.”
More information שעה 12:30 - 13:30מיקום בניין אולמן למדעי החייםמרצה Prof. David A Liberles
Dept. of Biology, Temple University, Philadelphia, PA, USAמארגן המחלקה למדעים ביומולקולרייםצרו קשר -
Date:24שנינובמבר 2014הרצאה
Indistinguishability Obfuscation of Probabilistic and Iterated Programs
More information שעה 14:30מיקום בניין יעקב זיסקינדמרצה Ran Canetti
Tel Aviv University and Boston Universityמארגן הפקולטה למתמטיקה ומדעי המחשב
Foundations of Computer Science Seminarצרו קשר -
Date:24שנינובמבר 2014הרצאה
A new state of matter: Dibaryons
More information שעה 14:45 - 15:45מיקום Hebrew University, Jerusalemמרצה M. Bashkanov
Physics Institute, Eberhard–Karls–Universitat Tubingenמארגן המחלקה לפיסיקה של חלקיקים ואסטרופיסיקה
Nuclear Physics Joint Seminarצרו קשר פרטים נוספים Show full text description of 14:30 - 14:45 Refreshments 15:45 - 16:15 Coffee Break...» 14:30 - 14:45 Refreshments
15:45 - 16:15 Coffee Breakתקציר Show full text abstract about Despite their long painful history dibaryon searches have re...» Despite their long painful history dibaryon searches have recently received new interest, in particular by the recognition that there are more complex quark configurations than just the familiar ̅qq and qqq systems. The "hidden color" aspect makes dibaryons a particularly interesting object in QCD.
A resonance like structure recently observed in double-pionic fusion to deuteron, at M=2.38 GeV with Γ= 70 MeV and (J_p)=0(3+) meanwhile proved to be the so called “inevitable dibaryon” d*(2380). To investigate its structure we have measured its decay branches into the dπ^0 π^0,dπ^+ π^-,ppπ^- π^0,pnπ^0 π^0 and pn channels.
d*(2380) dibaryon is robust enough to survive even in a nuclear surrounding, which may have interesting consequences for nuclear matter under extreme conditions. It has been shown that d* resonance can explain some dilepton yield in heavy-ion collisions (”DLS Puzzle”).
Various theoretical calculations on d* internal structure can be verified by future experiments in MAINZ and JLab. d*(2380) is unique multiquark system where the interplay between six-quark and molecular baryon-baryon components can be actually measured. Further investigations on d* dibaryon SU(3) multiplet companions as well as the mirror partners are expected to be done in near future by COSY, JLab, J-PARC and PANDA facilities.
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Date:24שנינובמבר 2014הרצאה
Order, chaos and persisting symmetries in a first-order quantum phase transition
More information שעה 16:15 - 17:45מיקום בניין הפיסיקה ע"ש עדנה וק.ב. וייסמןמרצה A. Leviatan
The Hebrew Universityמארגן המחלקה לפיסיקה של חלקיקים ואסטרופיסיקה
Nuclear Physics Joint Seminarצרו קשר תקציר Show full text abstract about Quantum phase transitions (QPTs) are structural changes in t...» Quantum phase transitions (QPTs) are structural changes in the properties of a physical system induced by a variation of parameters in the quantum Hamiltonian. In the present talk, we examine the order and chaos and persisting symmetries, accompanying a first-order QPT in nuclei. The Hamiltonian employed describes a QPT between spherical and deformed shapes, associated with U(5) and SU(3) dynamical symmetries, respectively. A classical analysis reveals a rich but simply-divided phase space structure with a Henon-Heiles type of chaotic dynamics ascribed to the spherical minimum, coexisting with a robustly regular dynamics ascribed to the deformed minimum in the Landau potential. A quantum analysis discloses regular U(5)-like multiplets in the spherical region and regular SU(3)-like rotational bands in the deformed region, which retain their identity amidst a complicated environment of other states. A symmetry analysis shows that these regular subsets of states, are associated with partial U(5) dynamical symmetry (PDS) and SU(3) quasi-dynamical symmetry (QDS),
respectively.
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Date:25שלישינובמבר 2014הרצאה
COLOR STRUCTURES FOR SCATTERING AMPLITUDES
More information שעה 10:30מיקום Neve Shalomמרצה BARAK KOL
HEBREW UNIVERSITYמארגן המחלקה לפיסיקה של חלקיקים ואסטרופיסיקה
High Energy Theory Joint Seminarצרו קשר פרטים נוספים Show full text description of 10:20 Gathering and coffee...» 10:20 Gathering and coffeeתקציר Show full text abstract about Perturbative gauge theory is currently making fascinating fa...» Perturbative gauge theory is currently making fascinating fast-pace progress, known as "scattering amplitudes". The first step in determining Yang-Mills scattering amplitudes is the separation of color and kinematics leading to the definition of color-ordered sub-amplitudes. We gain new insight into color structures through the role of the shuffle and split operations on the algebra of words made of the color alphabet. Then we formulate a novel question about the transformation of color structures under permutations, and we find the full answer for tree level and 1-loop. We discuss implications for sub-amplitudes. It is amusing to note that new insights and results were achieved even in such a heavily studied topic. -
Date:25שלישינובמבר 2014הרצאה
Chemical Physics Guest Seminar
More information שעה 11:00כותרת All for one and one for all: interplay of the excess charge in molecular anionsמיקום אולם הרצאות ע"ש גרהרד שמידטמרצה Dr Shachar Klaiman
University of Heidelberg, Germanyמארגן המחלקה לפיסיקה כימית וביולוגיתצרו קשר תקציר Show full text abstract about Molecular anions are of fundamental importance and ubiquitou...» Molecular anions are of fundamental importance and ubiquitous in many chemical, physical and biological environments. The chemical and physical properties of anions are very different from their neutral or cationic counterparts making them interesting species to study and characterize. While it is straightforward to assert that excited states of the anion play a crucial role in the electron accepting capabilities of the neutral molecules, electronically stable excited states of anions are thought to be scarce at best.
Following an overview of the special characteristic of molecular anions, we shall present our study of the electronically bound spectrum of the anion. Much like the neutral fullerene, the anion possesses certain unique properties which have attracted a great deal of research. One of these special properties, only recently fully uncovered, is that the anion supports a substantial number of electronically stable excited states in contrast to other molecular anions with comparable electron affinity. In this work, we clarify how the anion can support so many stable states by analyzing the radial and angular distributions of the excess electron bound to the anion. The analysis is based on ab initio calculations which are by far the most accurate on the anion to date. Surprisingly, the radial distributions are highly similar for states of very different binding energies and the analysis stresses the importance of angular correlation in binding the excess electron.
We further analyze the effect of the single excess electron on the electrons of the underlying neutral molecule. We demonstrate how this substantially modifies the actual distribution of the excess charge by shifting the underlying electron density. Finally, the effect of the perturbation of the anionic states in the presence of incarcerated atoms within the carbon shell is analyzed and discussed.
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Date:25שלישינובמבר 2014הרצאה
"From Walking Crowns and Switchable Rotaxanes on Surfaces to Logics with Gels"
More information שעה 11:00 - 12:00מיקום בניין הלן ומילטון קימלמןמרצה Prof. Christoph Schalley
Freie Universitat Berlinמארגן המחלקה לכימיה מולקולרית ולמדע חומריםצרו קשר -
Date:25שלישינובמבר 2014הרצאה
Grant presentation on Analysis, Design & Experimental Evolution of Novel Carbon Fixation Pathways
More information שעה 11:15מיקום בניין אולמן למדעי החייםמרצה Prof. Ron Milo
Department of Plant and Environmental Sciences, WISמארגן המחלקה למדעי הצמח והסביבהצרו קשר -
Date:25שלישינובמבר 2014הרצאה
TWO BODY SCATTERINGS AND DUALITY IN CHERN-SIMONS VECTOR MODELS
More information שעה 12:00מיקום Neve Shalomמרצה SHUICHI YOKOYAMA
TECHNIONמארגן המחלקה לפיסיקה של חלקיקים ואסטרופיסיקה
High Energy Theory Joint Seminarצרו קשר תקציר Show full text abstract about A scattering amplitude of elementary fields is a basic objec...» A scattering amplitude of elementary fields is a basic object to understand important physics not only in particle physics but also in a general quantum field theory (QFT), such as crossing symmetry and unitarity. In this talk I will talk about two body scattering amplitudes in Chern-Simons vector models, in which there has been a big progress recently. One of novel interesting phenomena discovered in this class of QFTs is non-supersymmetric duality. A main goal of this talk will be to explain our conjectural answer of the two body scatterings, which encode non-SUSY duality as well as crossing symmetry and unitarity. -
Date:25שלישינובמבר 2014הרצאה
Neural Correlates of Multisensory Plasticity
More information שעה 12:30מיקום אולם הרצאות ע"ש גרהרד שמידטמרצה Dr. Adam Zaidel
Gonda Multidisciplinary Brain Research Center Bar Ilan Universityמארגן המחלקה למדעי המוחצרו קשר תקציר Show full text abstract about The ability of the brain to processes and adapt multiple sou...» The ability of the brain to processes and adapt multiple sources of information dynamically, underlies its adept capacity for perception, decision making and action. In this talk, I shall present recent findings of multisensory (visual-vestibular) calibration in behaving monkeys and its neural correlate. Two mechanisms of multisensory calibration were found: i) in the absence of external feedback, “unsupervised” calibration reduces cue conflict by shifting the cues towards one another, and ii) “supervised” calibration reduces conflict with external feedback, by shifting the cues together, in the same direction. Strikingly, supervised calibration can cause an initially accurate cue to shift away from feedback, becoming less accurate. A computational model in which supervised and unsupervised calibration work in parallel, where the former only relies on the multisensory percept, but the latter calibrates cues individually, accounts for the observed behavior. Intriguingly, multisensory tuning curves in the ventral intraparietal (VIP) area shift together with behavioral calibration. While unsupervised calibration likely represents an implicit shift in perception, supervised calibration may incorporate higher level, more explicit, control of multisensory processing. -
Date:25שלישינובמבר 2014אירועי תרבות
מנחה מוזיקלית
More information שעה 12:30 - 13:30כותרת שיר למכשירמיקום אולם ע"ש דולפי ולולה אבנרצרו קשר פרטים נוספים Show full text description of דואטים של הנרי פרסל על אהבה , פוליטיקה , יין, זקנה וגם שיר ש...» דואטים של הנרי פרסל על אהבה , פוליטיקה , יין, זקנה וגם שיר שהוא חידה על מכשיר מעבדה מופלא
יעלה אביטל , סופרן
אהוד שפירא , בס
יזהר קרשון , צ'מבלו -
Date:25שלישינובמבר 2014הרצאה
“Fidelity of Translation: Universal Pathway of Editing Reactions”
More information שעה 14:00 - 15:00מיקום בניין הלן ומילטון קימלמןמרצה Prof. Mark Safro
Department of Structural Biology WISמארגן המחלקה לביולוגיה מבנית וכימיתצרו קשר -
Date:25שלישינובמבר 2014הרצאה
The Brain’s Gatekeeper: New Approaches to Study the Formation and Function of the Blood Brain Barrier (BBB)
More information שעה 15:00 - 16:00מיקום בניין ארתור ורושל בלפר למחקר ביורפואימרצה Ayal Ben-Zvi
Developmental Biology and Cancer Research Faculty of Medicine The Hebrew University of Jerusalemמארגן המחלקה למדעים ביומולקולרייםדף בית צרו קשר -
Date:26רביעינובמבר 2014הרצאה
STATISTICAL MECHANICS DAY
More information שעה 09:30 - 16:30מיקום בניין הפיסיקה ע"ש עדנה וק.ב. וייסמן
Auditoriumמארגן המחלקה לפיסיקה של מערכות מורכבות
Statistical Physics Seminarצרו קשר פרטים נוספים Show full text description of 09:30 – 09:40 Opening Remarks – David M...» 09:30 – 09:40 Opening Remarks – David Mukamel
09:40 – 10:00 Satya Majumdar, University of Paris, Orsay
Universal Order and Gap Statistics of Critical Branching Brownian Motion.
10:00 – 10:20 Yair Shokef, Tel-Aviv University
Confinement Effects on the Jamming Transition in Kinetically-Constrained Models.
10:20 – 10:40 Yariv Kafri, Technion
Pressure in non-equilibrium (active) systems.
10:40 – 11:00 Baruch Meerson, Hebrew University
Smoluchowski with interactions.
Coffee Break
11:30 – 11:50 Efi Efrati, Weizmann Institute
Chiral self-assembly: Depletion interaction with a twist.
11:50 – 12:10 Eytan Katzav, Hebrew University
Yield-Optimised Superoscillations.
12:10 – 12:30 Uzy Smilansky, Weizmann Institute
Spectral statistics of random Bernoulli matrix ensembles- a random walk approach.
12:30 – 12:50 Itzhack Dana, Bar-Ilan University
Statistical Approach to Quantum-Chaotic Ratchets.
Lunch Break
14:00 – 14:20 Erez Braun, Technion
Universality and collective modes: relevant and irrelevant variables in the living cell.
14:20 – 14:40 Nir Davidson, Weizmann Institute
Phase synchronization of laser networks with time-delayed coupling and disorder.
14:40 – 15:00 Oded Farago, Ben-Gurion University
Inertial Langevin dynamics in inhomogeneous media.
Coffee Break
15:20 – 15:40 Gregory Falkovich, Weizmann Institute
Localization-delocalization phase transition for particles in a flow.
15:40 – 16:00 A. Zamolodchikov, University of Rutgers
Stress-energy identities in 2D systems near criticality.
16:00 – 16:20 V.V. Lebedev, Landau Institute
Passive scalar statistics in the laminar sublayer of turbulent flow: dramatic role of intermittency.
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Date:26רביעינובמבר 2014הרצאה
The human gut microbiota following medical interventions
More information שעה 10:00 - 11:00מיקום אולם הרצאות ע"ש גרהרד שמידט
Lecture Hallמרצה Dr. Uri Gophna
Department of Molecular Microbiology and Biotechnology TAUמארגן המחלקה למדעים ביומולקולרייםצרו קשר -
Date:26רביעינובמבר 2014הרצאה
Forum on Mathematical Principles in Biology
More information שעה 10:00 - 11:00כותרת Self/non-self discrimination in the CRISPR systemמיקום בניין ארתור ורושל בלפר למחקר ביורפואי
Botnar Auditoriumמרצה Rotem Sorekמארגן המחלקה לביולוגיה מולקולרית של התאצרו קשר