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February 06, 2013
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Date:16ThursdayApril 2026Lecture
Special PhD Defense Seminar
More information Time 11:00 - 14:00Title Towards Dephasingless Laser-Wakefield AccelerationLocation Nella and Leon Benoziyo Physics LibraryLecturer Aaron Rafael Liberman Organizer Department of Physics of Complex SystemsAbstract Show full text abstract about Laser-wakefield accelerators (LWFAs) have demonstrated the a...» Laser-wakefield accelerators (LWFAs) have demonstrated the ability to generate high-quality, monoenergetic electron beams. Yet, efforts to achieve higher electron energies and improved accelerator efficiency remain limited by several fundamental constraints, most notably electron dephasing and beam diffraction. One promising approach to mitigating these limitations is the use of structured light to control the on-axis propagation velocity within LWFAs. By combining the diffraction-resistant characteristics of Bessel beams with spatiotemporal pulse shaping, this method promises an improved balance of extended acceleration distances and strong accelerating gradients.In this talk, we report the first experimental observation of wakefields driven by such structured-light beams as well as the first experimental evidence of the mitigation of dephasing in electron acceleration. Spatiotemporally engineered laser pulses are focused using a specialized mirror to produce a quasi-Bessel beam, and the resulting wakefields are directly measured using femtosecond relativistic electron microscopy. Numerical simulations support the experimental observations and provide new insight into this largely unexplored regime. We experimentally demonstrate control over the on-axis propagation velocity of the wakefield and follow its evolution throughout the focal region. Furthermore, we investigate how targeted spatiotemporal modifications affect both the wakefield structure and its propagation velocity. Finally, we present the first successful acceleration of electrons using these wakefields. We compare the electron profiles obtained by wakefields traveling at different velocities, demonstrating that the faster wakefield is able to achieve a higher electron cutoff energy. By combing our data with insights from simulations, we suggest the first successful partial mitigation of dephasing with such techniques. Together, these results lay the groundwork for leveraging structured-light-based techniques to overcome dephasing limitations in LWFA systems. -
Date:16ThursdayApril 2026Lecture
Vision and AI
More information Time 12:15 - 13:15Title Toward Meaningful Diversity in Text-to-Image ModelsLocation Jacob Ziskind Building
Room 1 - 1 חדרLecturer Omer Dahary
TAUOrganizer Department of Computer Science and Applied MathematicsContact Abstract Show full text abstract about Modern text-to-image models achieve strong visual fidelity a...» Modern text-to-image models achieve strong visual fidelity and prompt alignment, but often at the cost of generative diversity.
In this talk, I will present two complementary approaches to this problem: a simple inference-time method that achieves rich diversity by intervening in the model’s internal representations, and a new formulation of controlled diversity, where users explore structured image galleries through meaningful semantic variations.
Bio:
Omer Dahary is a PhD student in Computer Science at Tel Aviv University, advised by Daniel Cohen-Or. His research focuses on generative models, with an emphasis on improving their ability to align with user control. -
Date:16ThursdayApril 2026Lecture
Why is aging the main risk factor for cancer?
More information Time 14:00 - 15:00Location Max and Lillian Candiotty Building
AuditoriumLecturer Prof. Uri Alon Organizer Dwek Institute for Cancer Therapy Research -
Date:19SundayApril 2026Lecture
The Clore Center for Biological Physics
More information Time 13:15 - 14:30Title A Langevin model for human aging and longevityLocation Nella and Leon Benoziyo Physics LibraryLecturer Prof. Uri Alon
LUNCH AT 12:45Contact Abstract Show full text abstract about Aging is characterized by several quantitative regularities:...» Aging is characterized by several quantitative regularities: mortality and disease incidence rise exponentially with age, organ function declines linearly, and species with very different lifespans exhibit similarly shaped survival curves. I will present recent developments that unify these quantitative phenomena within the framework of the Saturating Removal (SR) model. The SR model is a biologically motivated stochastic differential equation that describes aging as a damage accumulation process with linearly increasing production with time and saturating removal, with death and disease modeled as first-passage-time processes. I will discuss the statistical properties of the model, including how the exponential mortality increase emerges from a Kramers escape rate over a barrier. I will then present recent results showing how the model organizes aging across species into two distinct aging regimes- ballistic and quasi steady state. Comparing the model to human data, indicates that late-life survival and the extreme-value tail of exceptionally long-lived individuals constrain damage production and removal parameters in human populations. This model can help prioritize longevity interventions. I will discuss future directions and open questions. FOR THE LATEST UPDATES AND CONTENT ON SOFT MATTER AND BIOLOGICAL PHYSICS AT THE WEIZMANN, VISIT OUR WEBSITE: https://www.bio -
Date:20MondayApril 2026Cultural Events
In Memory of Or Moses (in Hebrew)
More information Time 12:00 - 13:00Title Light refreshments will be served in the lobby at 11:45Location Nella and Leon Benoziyo Building for Plant and Environmental Sciences
Auditorium floor 1Lecturer Yochi Moses
You are invited to a lecture (in Hebrew) by Yochi Moses about her daughter, Or Moses (of blessed memory), who fell on October 7, 2023, while bravely defending her soldiers at the Zikim training base.Organizer Department of Plant and Environmental Sciences -
Date:23ThursdayApril 2026Lecture
Revisiting Immune Checkpoints: New Targets, Glycans, and the Future of Cancer Immunotherapy
More information Time 14:00 - 15:00Location Max and Lillian Candiotty Building
AuditoriumLecturer Prof. Angel Porgador Organizer Dwek Institute for Cancer Therapy Research -
Date:26SundayApril 2026Lecture
Field-based insights into mechanical weathering (cracking) of rocks in desert landscapes on Earth & Mars
More information Time 11:00 - 12:00Location Earth and Planetary Sciences Complex
Seminar roomLecturer Dr Amit Mushkin Organizer Department of Earth and Planetary SciencesContact Abstract Show full text abstract about A suite of field experiments illuminate the intimate involve...» A suite of field experiments illuminate the intimate involvement of moisture in the progressive physical disintegration (cracking) process of surface rocks, even in extremely dry deserts, and in the formation of asymmetrical hyperarid landscapes on Earth and Mars. -
Date:27MondayApril 2026Lecture
PhD Defense seminar by Daniel Kovarsky (Prof. Itay Tirosh Lab)
More information Time 13:00 - 14:30Title Treating Glioblastoma Patients with Immunotherapy at Single-Cell ResolutioLocation Benoziyo Auditorium -
Date:27MondayApril 2026Academic Events
Seminar for PhD thesis defense
More information Time 14:00 - 15:00Title "Ubiquitination regulates granulostasis and DRiP accumulation in SGs under heat stress via the E3 ligase MKRN2"Location Arthur and Rochelle Belfer Building for Biomedical Research
Botnar AuditoriumLecturer Emmanuel Amzallag -
Date:28TuesdayApril 2026Lecture
iSCAR Breakfast Seminar
More information Time 10:00 - 11:00Title The Aging of the Blood SystemLocation Max and Lillian Candiotty Building
AuditoriumLecturer Prof. Liran Shlush Organizer Department of Immunology and Regenerative BiologyContact -
Date:28TuesdayApril 2026Lecture
Mathematics Colloquium
More information Time 11:10 - 12:15Title Noncommutative inclusion-exclusion, bands, and the Tsetlin libraryLocation Jacob Ziskind Building
Room 155 - חדר 155Lecturer Uzi Vishne
Bar Ilan UniversityOrganizer Department of MathematicsContact Abstract Show full text abstract about The dimension of the space of Specht polynomials is n!/e to ...» The dimension of the space of Specht polynomials is n!/e to the nearest integer. I will explain how the search for a combinatorial reason behind this unexpected formula leads to a web of ideas involving Markov models, semigroups, partial representations, exact complexes, and covering problems for distributions on permutations. -
Date:28TuesdayApril 2026Lecture
Probing and Modulating Transcription Factor–DNA Interactions with Chemically Modified Proteins
More information Time 11:15 - 12:15Location Gerhard M.J. Schmidt Lecture HallLecturer Dr. Muhammad Jbara Organizer Department of Chemical and Structural Biology -
Date:28TuesdayApril 2026Lecture
PES Department Seminar – Dr. Yotam Zait (HUJI)
More information Time 11:30 - 12:30Location Nella and Leon Benoziyo Building for Plant and Environmental Sciences
Auditorium Floor 1 -
Date:28TuesdayApril 2026Lecture
Dissociating vicarious distress from prosocial motivation using the rat helping behavior test
More information Time 12:30 - 13:30Location Gerhard M.J. Schmidt Lecture HallLecturer Prof. Inbal Ben Ami Bartal Organizer Department of Brain SciencesContact Abstract Show full text abstract about What are the neural processes that lead to a decision to app...» What are the neural processes that lead to a decision to approach another individual in need and help them out of a tight spot? Multiple factors weigh in on this decision, including empathic arousal and social identity. The drive to act prosocially in response to others distress is evolutionarily rooted in mechanisms underlying parental behavior and group living. In humans, helping involves socio-emotional and cognitive components, and recruits brain regions involved in affective empathy arousal, executive function and motivation. This talk will present an overview of the rat Helping Behavior Test, which investigates the complex response leading to rescue of trapped conspecifics, and examine evidence to ask whether similar capacities are involved in rat helping. We’ll explore the idea that rat helping is motivated by empathy, what is the difference between social and prosocial reward, and whether helping is motivated by valuation of others’ outcomes. I will share what we’ve learned about the distinct neural network that is associated with empathy and prosocial behavior, and discuss findings of ingroup bias, adolescent helping, and interactions with rat immune function and wellbeing. We’ll ask what is the link between prosocial motivation and aggression, and what is the role of the social group in these behaviors. -
Date:29WednesdayApril 2026Academic Events
Seminar for PhD thesis defense
More information Time 22:00 - 23:00Title Developmental parthanatos cell death is mediated by lipid dropletsLocation Arnold R. Meyer Building
106Lecturer Guy Hadary -
Date:04MondayMay 2026Lecture
Foundations of Computer Science Seminar
More information Time 11:15 - 12:15Title Recent Progress on Extractors for Samplable DistributionsLocation Jacob Ziskind Building
Lecture Hall - Room 1 - אולם הרצאות חדר 1Lecturer Ronen Shaltiel
University of HaifaOrganizer Department of Computer Science and Applied MathematicsContact Abstract Show full text abstract about In an influential paper, Trevisan and Vadhan (FOCS 2000) int...» In an influential paper, Trevisan and Vadhan (FOCS 2000) introduced the notion of (seedless) extractors for samplable distributions (namely, distributions that can be sampled by a poly-size circuit). Trevisan and Vadhan showed that under a strong complexity theoretic hardness assumption, there are extractors for samplable distributions with large min-entropy of $k=(1-\gamma) \cdot n$, for some small constant $\gamma>0$.
Recently, there has been significant progress in this area, and extractors for samplable distributions with much lower min-entropy were constructed.
In the talk, I will explain the motivation for extractors for samplable distributions, and the relation of this area to the well known area of worst-case to average-case hardness amplification. I will give a high level overview of the Trevisan-Vadhan construction, and will also explain some of the recent constructions.
This talk is based on several recent joint works with Marshall Ball, Justin Oh and Jad Silbak. -
Date:04MondayMay 2026Cultural Events
Weizmann Ornithology monthly lecture: Migration timing and routes of GPS-tagged European Turtle-doves from Israel
More information Time 14:30 - 16:30Title Refreshments served14:10 zoom passcode 311626Location Nella and Leon Benoziyo Building for Plant and Environmental Sciences
590C between the elevatoreLecturer Dr. Yoav Perlman Contact -
Date:06WednesdayMay 2026Lecture
Life Sciences Luncheon
More information Time 12:30 - 14:00Title Prof. Schraga SchwartzLocation Nella and Leon Benoziyo Building for Biological Sciences
AuditoriumLecturer Prof. Schraga Schwartz Contact -
Date:07ThursdayMay 2026Lecture
Vision and AI
More information Time 12:15 - 13:15Title Prox-E: Fine-Grained 3D Shape Editing via Primitive-Based AbstractionsLocation Jacob Ziskind Building
Lecture Hall - Room 1 - אולם הרצאות חדר 1Lecturer Etai Sella
TAUOrganizer Department of Computer Science and Applied MathematicsContact Abstract Show full text abstract about Text-based 2D image editing models have recently reached an ...» Text-based 2D image editing models have recently reached an impressive level of maturity, motivating a growing body of work that uses them to drive 3D edits. While effective for appearance-based modifications, such 2D-centric 3D editing pipelines often struggle with fine-grained 3D editing, where localized structural changes must be applied while strictly preserving an object’s overall identity.
To address this limitation, we propose Prox-E, a training-free framework that enables fine-grained 3D control through an explicit, primitive-based geometric abstraction. Our framework first abstracts an input 3D shape into a compact set of geometric primitives. A pretrained vision-language model then edits this abstraction to specify primitive-level changes, which are subsequently used to guide a 3D generative model. This enables fine-grained, localized modifications while preserving unchanged regions of the original shape.
Through extensive experiments, we show that Prox-E consistently balances identity preservation, shape quality, and instruction fidelity more effectively than existing approaches, including 2D-based 3D editors and training-based methods.
Bio:
Etai Sella is a fourth-year PhD student at Tel Aviv University, supervised by Hadar Averbuch-Elor and Or Patashnik. His research focuses on making generative AI more controllable and editable, with an emphasis on 3D editing. He is currently an intern at Snap Research. -
Date:11MondayMay 2026Colloquia
Chemistry colloquium
More information Time 11:00 - 12:15Location Gerhard M.J. Schmidt Lecture HallLecturer Prof. Ron Naaman Homepage