Pages

February 05, 2018

  • Date:21WednesdayMay 2025

    Machine Learning and Statistics Seminar

    More information
    Time
    11:15 - 12:15
    Title
    Learning infinitely many coins simultaneously
    Location
    Jacob Ziskind Building
    Room 1 - 1 חדר
    LecturerAryeh Kontorovich
    Ben Gurion University
    Organizer
    Department of Computer Science and Applied Mathematics
    Contact
    AbstractShow full text abstract about Inferring the bias of a single coin from independent flips i...»
    Inferring the bias of a single coin from independent flips is a well-understood problem, technically known as estimating the Bernoulli parameter p. In particular, how the sample size (number of flips) n, the precision ε, and the confidence δ constrain each other is known within tight upper and lower bounds. When we want to estimate the bias of d coins simultaneously, this problem is well-understood as well, at least in the worst case over the Bernoulli parameters pᵢ. What if we want to estimate infinitely many pᵢ's simultaneously?

    A simple argument shows that this is impossible in the "worst case" over the pᵢ's; thus, any result must depend on their actual values. If we define M as the expected maximum deviation between any pᵢ and its estimate, we want to understand for which sequences pᵢ this quantity decays to zero and at what rate. We obtain tight, exhaustive answers to these questions.

    The exhaustive answers mentioned above were obtained for independent (or negatively dependent) Bernoullis. Allowing positive dependencies complicates the story significantly. We have upper and lower bounds but no simple general characterization of convergence.

    Joint work with Moïse Blanchard, Doron Cohen, Václav Voráček 

    https://arxiv.org/abs/2209.04054

    https://arxiv.org/abs/2402.07058

    Aryeh Kontorovich received his undergraduate degree in mathematics with a certificate in applied mathematics from Princeton University in 2001. His M.Sc. and Ph.D. are from Carnegie Mellon University, where he graduated in 2007. After a postdoctoral fellowship at the Weizmann Institute of Science, he joined the Computer Science department at Ben-Gurion University of the Negev in 2009, where he is currently a full professor. His research interests are mainly in machine learning, with a focus on probability, statistics, Markov chains, and metric spaces.
    He served as the director of the Ben-Gurion University Data Science Research Center during 2021-2022.
    Lecture
  • Date:21WednesdayMay 2025

    Spotlight on Science - Making Sense of Order: From Structure to Function

    More information
    Time
    12:30 - 14:00
    Location
    Gerhard M.J. Schmidt Lecture Hall
    LecturerDr. Yael Diskin-Posner
    Spotlight on Science lecture sponsored by the Staff Scientists Council
    Contact
    Lecture
  • Date:22ThursdayMay 2025

    Physics Colloquium

    More information
    Time
    11:15 - 12:15
    Title
    Beyond Images: Leveraging Stable Diffusion Techniques for Particle Physics Simulations
    Location
    Physics Weissman Auditorium
    LecturerProf. Eilam Gross
    Organizer
    Department of Particle Physics and Astrophysics
    AbstractShow full text abstract about Generative AI models, including those behind image creation ...»
    Generative AI models, including those behind image creation tools, have shown remarkable capabilities in transforming random inputs into coherent outputs. Inspired by these advancements, we've developed Parnassus, a deep-learning model designed for particle physics. Parnassus processes point clouds representing particles interacting with a detector and outputs reconstructed particle data.  Parnassus accurately replicates the particle flow algorithm and generalizes well beyond its training set. This approach exemplifies how techniques from image generation can be adapted to accelerate simulations in high-energy physics.
    Colloquia
  • Date:22ThursdayMay 2025

    Vision and AI

    More information
    Time
    12:15 - 13:15
    Title
    A Computational Study of Shaping Toddler Vision and Object Semantics though Caregive Talk and Self-Supervised Learning
    Location
    Jacob Ziskind Building
    Room 1 - 1 חדר
    LecturerGemma Roig
    Goethe University Frankfurt
    Organizer
    Department of Computer Science and Applied Mathematics
    Contact
    AbstractShow full text abstract about Infants gradually learn to recognize and categorize objects,...»
    Infants gradually learn to recognize and categorize objects, a process that is influenced by language. This talk explores how caregivers' naming of objects, even if inconsistent and unclear, can enhance a child's visual understanding. Using a computer model and a synthetic set of images seen by a toddler-like agent during play, we study how matching images and words over time improves category recognition. Our findings show that small changes in how often objects are named can significantly affect learning, highlighting the importance of aligning visual and language inputs. We also discuss how humans learn relationships between objects. Using a bio-inspired neural network model, we simulate visual experiences to see how objects are grouped based on context, like kitchen or bedroom scenes. Our results reveal that higher network layers group objects by context, while lower layers focus on object identity. This dual approach of matching visuals with words and timing helps explain how we develop semantic knowledge. Overall, this talk suggests computational models to explore the role of language and context in shaping visual and semantic learning in early development.

    Bio:
    Gemma is a full professor (W3) at the Computer Science Department in Goethe University Frankfurt. She is also a hessian.AI member and affiliated at the Center for Brains Minds and Machines at MIT. Before, she was assistant prof. at Singapore University of Technology and Design. Previously, she was a postdoc fellow at MIT in the Center for Brains Minds and Machines with Prof. Tomaso Poggio. She was also affiliated at the Laboratory for Computational and Statistical Learning. She pursued her doctoral degree in Computer Vision at ETH Zurich.
    Lecture
  • Date:22ThursdayMay 2025

    Cancer aneuploidy: From evolutionary pressures to cellular vulnerabilities

    More information
    Time
    14:00 - 15:00
    Location
    Max and Lillian Candiotty Building
    Auditorium
    LecturerProf. Uri Ben-David
    Organizer
    Dwek Institute for Cancer Therapy Research
    Lecture
  • Date:25SundayMay 2025

    On the role of domain aspect ratio in the westward intensification of wind-driven surface ocean circulation

    More information
    Time
    11:00 - 12:00
    Location
    Sussman Family Building for Environmental Sciences
    M. Magaritz seminar room
    LecturerHezi Gildor
    Organizer
    Department of Earth and Planetary Sciences
    AbstractShow full text abstract about Western boundary currents (WBCs)—such as the Gulf Stream and...»
    Western boundary currents (WBCs)—such as the Gulf Stream and Kuroshio—are prominent features of the wind-driven surface ocean circulation. Their structure and dynamics have traditionally been explained by the seminal models of Stommel (1948) and Munk (1950), which emphasize the roles of wind-stress curl, friction, and the planetary vorticity gradient (β-effect). However, these classical theories largely overlook the influence of basin geometry. In this talk, we revisit the Stommel–Munk framework through a non-dimensional approach that isolates two key parameters: frictional damping and the domain aspect ratio, defined as the meridional-to-zonal extent of the ocean basin. Analytical solutions and numerical simulations show that WBC transport increases strongly with the aspect ratio—cubic in Stommel’s model and linear in Munk’s. This geometric dependence helps explain why the East Australian Current is weaker than other WBCs. Extending these insights to paleoclimate, we demonstrate that tectonic changes during the Cretaceous modified basin shapes, weakening gyre circulation and thereby reducing poleward oceanic heat transport. This reduction likely contributed to the larger meridional sea surface temperature gradients observed during that period. Our findings underscore the fundamental role of basin geometry in shaping both modern and ancient ocean circulation.
    Lecture
  • Date:25SundayMay 2025

    The Clore Center for Biological Physics

    More information
    Time
    12:45 - 14:30
    Title
    Self-assembled active elastic gels spontaneously curve and wrinkle similar to biological cells and tissues
    Location
    Nella and Leon Benoziyo Physics Library
    LecturerProf. Anne Bernheim
    Lunch at 12:45
    Contact
    AbstractShow full text abstract about  Living systems from individual cells to entire tis...»
     Living systems from individual cells to entire tissues adopt diverse curved shapes, appearing on many length scales and commonly driven by active contractile stresses generated in the cell cytoskeleton. Yet, how these forces generate specific 3D forms remains unclear. By recreating the cell cytoskeleton from basic components, with precisely controlled composition and initial geometry, we demonstrate that the spontaneous buildup of stress gradients generated by these molecular motors drive shape deformation. We identify the shape selection rules that determine the final adopted configurations. These are encoded in the initial radius to thickness aspect ratio, likely indicating shaping scalability. These results provide insights on the mechanically induced spontaneous shape transitions in contractile active matter, revealing potential shared mechanisms with living systems across scales.  FOR THE LATEST UPDATES AND CONTENT ON SOFT MATTER AND BIOLOGICAL PHYSICS AT THE WEIZMANN, VISIT OUR WEBSITE: https://www.biosoftweizmann.com/
    Lecture
  • Date:26MondayMay 2025

    MSc thesis Seminar- Reut Shabtai

    More information
    Time
    09:00 - 10:00
    Title
    Microbial Adaptations in a Subterranean Dark Ecosystem Insights from the Ayyalon Cave System
    Location
    Nella and Leon Benoziyo Building for Plant and Environmental Sciences
    690
    Contact
    Academic Events
  • Date:26MondayMay 2025

    Special Guest Seminar

    More information
    Time
    11:00 - 12:00
    Title
    Mapping Inherited Bacterial Heterogeneity in Human Infections
    Location
    Max and Lillian Candiotty Building
    Auditorium
    LecturerDr. Raya Faigenbaum
    Organizer
    Department of Immunology and Regenerative Biology
    Contact
    Lecture
  • Date:26MondayMay 2025

    AI Acceleration Grants Colloquium

    More information
    Time
    11:00 - 14:00
    Location
    The David Lopatie Conference Centre
    Organizer
    Knell Family Institute of Artificial Intelligence
    Contact
    AbstractShow full text abstract about Event highlighting the innovative research supported by this...»
    Event highlighting the innovative research supported by this year’s AI Institute Acceleration Grants. The colloquium will feature presentations from all 10 grant recipients- showing their projects focused on using AI to tackle scientific questions. This is a great opportunity to learn about cutting-edge work, hear about new ideas, and connect with fellow scientists across disciplines.
    Colloquia
  • Date:26MondayMay 2025

    Midrasha on Groups Seminar

    More information
    Time
    11:15 - 13:00
    Title
    Ramanujan graphs and interlacing families
    Location
    Elaine and Bram Goldsmith Building for Mathematics and Computer Sciences
    Room 208 - חדר 208
    LecturerElad Tzalic
    Weizmann
    Organizer
    Department of Mathematics
    Contact
    AbstractShow full text abstract about I will explain the construction of Ramanujan graphs based on...»
    I will explain the construction of Ramanujan graphs based on the “method of interlacing families” introduced by Adam Marcus, Daniel Spielman and Nikhil Srivastava. This method was also used to prove two theorems known to imply a positive solution to the celebrated Kadison–Singer problem.
    Lecture
  • Date:26MondayMay 2025

    Midrasha on Groups Seminar

    More information
    Time
    14:15 - 16:00
    Title
    Periodicity of joint co-tiles in Z^d
    Location
    Jacob Ziskind Building
    Room 1 - 1 חדר
    LecturerYaar Solomon
    BGU
    Organizer
    Department of Mathematics
    Contact
    AbstractShow full text abstract about The periodic tiling conjecture in Z^d asserts that if a tile...»
    The periodic tiling conjecture in Z^d asserts that if a tile (=finite set) tiles Z^d, then it must also tile it periodically. In dimension d=1, an old theorem of Newman shows an even stronger assertion, which is that every tiling of Z is itself periodic. Very recently, Greenfeld and Tao showed that the periodic tiling conjecture is false in large enough dimension d. On the other hand, Bhattacharya recently proved for d=2 that the periodic tiling conjecture is true. In this talk, after giving all the definitions and background, I'll explain how (in spite of Greenfeld–Tao counterexample) both Newman's and Bhattacharya's theorems can be extended to any dimension d, with a slightly different statement and setup.
    Lecture
  • Date:27TuesdayMay 2025

    Unlocking the Night: Novel Approaches Advancing the Neuroscience of Sleep and Cognition

    More information
    Time
    12:30 - 13:30
    Location
    Gerhard M.J. Schmidt Lecture Hall
    LecturerProf. Yuval Nir
    Organizer
    Department of Brain Sciences
    Contact
    AbstractShow full text abstract about In this talk, I will present recent studies in our lab, wher...»
    In this talk, I will present recent studies in our lab, where new tools are pushing the boundaries of sleep research.In a first line of studies, we are investigating how sleep promotes memory consolidation in humans. To this end, we developed a novel ecological paradigm to study episodic memory without report; upon repeated viewing of special movies ,eye gaze patterns can quantify memory for specific events. Next, we show that deep brain closed-loop intracranial electrical stimulation during human sleep enhances hippocampus-cortex synchrony and memory performance. Finally, we examine how sleep and memory are disrupted in amnestic mild cognitive impairment (aMCI) representing early Alzheimer’s disease (AD). To this end, we developed a novelmachine learning-based method to non-invasively detect interictal spikes occurring in the medial temporal lobe during sleep. This approach can help identify disruptions in hippocampus-cortex synchrony and memory consolidation during sleep.In the second line of studies, we investigate how reduced locus coeruleus-noradrenaline (LC-NE) activity during sleep mediates sensory disconnection. In rodents, the level of ongoing tonic LC activity during sleep anticipates sound-evoked awakenings, while minimal optogenetic LC activation or silencing increases and decreases such awakenings, respectively. Projection-specific investigation in mice indicates that an early surge of brainstem NE is particularly important for mediating sensory-evoked awakenings. These findings may shift how we view arousal- promoting neuromodulation; rather than acting in a diffuse hormonal-like manner, the LC-NE system may in fact operate through specific projection pathways, in a circuit-like manner. Finally, I will describe a novel method for monitoring gaze direction and pupil size through closed eyes in humans via short-wave infrared (SWIR) imaging in combination with video analysis algorithms. This technology has potential to enable touchless and continuous monitoring of depth of anesthesia, pain, and detection of intraoperative awareness.
    Lecture
  • Date:27TuesdayMay 2025

    A Roller Coaster Ride Through Molecular Crowding: From Test Tube to Tissue

    More information
    Time
    14:00 - 15:00
    Location
    Gerhard M.J. Schmidt Lecture Hall
    LecturerDr. Debabrata Dey
    Organizer
    Department of Chemical and Structural Biology
    Lecture
  • Date:27TuesdayMay 2025

    EPS AI discussion: Geospatial AI Foundation Models

    More information
    Time
    15:00 - 16:00
    Location
    Sussman Family Building for Environmental Sciences
    LecturerHendrik Hamann
    Organizer
    Department of Earth and Planetary Sciences
    AbstractShow full text abstract about In recent years, the landscape of artificial intelligence (A...»
    In recent years, the landscape of artificial intelligence (AI) has been reshaped by the rapid emergence of Foundation Models (FMs). These versatile models have garnered widespread attention for their remarkable ability to transcend the boundaries of traditional, bespoke AI solutions and to generalize to a large set of downstream tasks.   In this presentation we will describe the development of geospatial FMs with earth observation and weather data and discuss the initial results of such models when fine-tuned to various applications including flood detection, CO2 monitoring, nature-based carbon sequestration. We will also show how such foundation models can be a new and exciting tool for assisting and accelerating scientific discovery.
    Lecture
  • Date:29ThursdayMay 2025

    Ribosomal Dynamics in Hematopoiesis and Viral Infectionced

    More information
    Time
    10:00 - 11:00
    Location
    Nella and Leon Benoziyo Building for Biological Sciences
    Auditorium Rm. 191
    LecturerDr. Daphna Nachmani
    (HUJI)
    AbstractShow full text abstract about Faculty of Science – The Hebrew University of Jerusalem ...»
    Faculty of Science – The Hebrew University of Jerusalem
    Lecture
  • Date:29ThursdayMay 2025

    Physics Colloquium

    More information
    Time
    11:15 - 12:30
    Title
    Extra-solar Planets: Historical Perspective
    Location
    Physics Weissman Auditorium
    LecturerProf. Tsevi Mazeh
    AbstractShow full text abstract about Since the groundbreaking discovery of 51 Pegasi b in 1995, a...»
    Since the groundbreaking discovery of 51 Pegasi b in 1995, a few thousands extra-solar planets have been identified, marking the beginning of a rapidly evolving new field in Astronomy. This talk will trace the history of exoplanet research and explore how these discoveries have reshaped our understanding of planetary formation and opening new frontiers in the study of planetary systems.
    Colloquia
  • Date:03TuesdayJune 2025

    FTH1–NCOA4 Complex: Structural Basis for the Intracellular Regulation of Ferritin Degradation

    More information
    Time
    14:00 - 15:00
    Location
    Gerhard M.J. Schmidt Lecture Hall
    LecturerDr. Gabriel Frank
    Organizer
    Department of Chemical and Structural Biology
    Lecture
  • Date:03TuesdayJune 2025

    Isolating the Anthropogenic Effect in Soil Spectroscopy and Digital Soil Mapping

    More information
    Time
    14:00 - 15:00
    Location
    via zoom only
    LecturerNicolas Francos
    Lecture
  • Date:04WednesdayJune 2025

    students seminar series- Azrieli

    More information
    Time
    10:30 - 12:30
    Location
    Camelia Botnar Building
    Contact
    Lecture

Pages