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Date:22SundayDecember 2024Lecture
Making Climate Tech Work – Policies that Drive Innovation
More information Time 13:00 - 14:00Location Nella and Leon Benoziyo Building for Plant and Environmental SciencesLecturer Prof. Alon Tal
Host: Prof. Ron Milo, IES DirectorOrganizer The Institute for Environmental Sustainability , Sustainability and Energy Research Initiative (SAERI)Contact -
Date:22SundayDecember 2024Lecture
The Clore Center for Biological Physics
More information Time 13:15 - 14:30Title The harmonic three-body problem: from gauge field theory of falling cats to fractional rotational diffusionLocation Nella and Leon Benoziyo Physics LibraryLecturer Prof. Efi Efrati
lunch will be served at 12:45Organizer Clore Center for Biological PhysicsContact Abstract Show full text abstract about <p> </p><p>In this talk I will pr...» <p> </p><p>In this talk I will present the study of the non-holonomic rotational dynamics of the classical harmonic three mass system in the strongly nonlinear regime. This is the simplest isolated spring-mass system capable of displaying rotation with zero angular momentum as well as chaotic dynamics. Combined together these two phenomena lead to a wide variety of qualitatively distinct dynamical phases as a function of the system's internal energy. <br>For low energy, where dynamics are regular, we observe a constant rotation rate with zero angular momentum. For sufficiently high energy we observe a rotational random walk driven by the system's internal chaotic dynamics. For intermediate energies, we observe ballistic bouts of constant rotation rates interrupted by unpredictable orientation reversal events. In this regime, the system constitutes a simple physical model for Levy walks and the orientation reversal statistics lead to fractional rotational diffusion interpolating smoothly between the ballistic and regular diffusive regimes.</p><p> </p><p><strong>FOR THE LATEST UPDATES AND CONTENT ON SOFT MATTER AND BIOLOGICAL PHYSICS AT THE WEIZMANN, VISIT OUR WEBSITE</strong>: https://www.biosoftweizmann.com/</p><p> </p> -
Date:23MondayDecember 2024Lecture
The Israel Rubinstein 4th Memorial Lecture -"The challenge of rechargeable batteries with very high energy density and prolonged cycle life: from basic science to practical devices"
More information Time 11:00 - 12:00Location Gerhard M.J. Schmidt Lecture HallLecturer Prof. Doron Aurbach
Bar Ilan University, Department of ChemistryOrganizer Department of Molecular Chemistry and Materials ScienceContact Abstract Show full text abstract about The development of high energy density, long running recharg...» The development of high energy density, long running rechargeable batteries like
Li ion batteries, that power so successfully all mobile electronic devices, can be
considered as the greatest success of modern electrochemistry.
However, the basis for this success was the capability of exploring most complex
electrodes, electrolyte solutions and reactive interfaces by most sophisticated
electroanalytical tools in conjunction with advanced spectroscopic and microscopic
was a first-rate leader in electroanalytical ז"ל techniques. Professor Israel Rubinstein
chemistry. I learned a lot from him.
The main theme of this presentation is to examine what is the true horizons for advanced
high energy density batteries that can promote the electro-mobility revolution. The
limiting factor in Li-ion batteries in terms of energy density, cost, potential, durability
and cycling efficiency are the cathode materials used. We will examine most energetic
cathode materials and novel approaches we developed for their stabilization. We
describe in this lecture which electrode materials can be relevant, methodologies
of their stabilization by doping, coating, and affecting electrodes surface chemistry
by the use of active additives. Most important cathode materials are comprising the
5 elements Li,Ni,Co,Mn,O at different stoichiometries that determine voltage and
specific capacities. We will explain how the stoichiometry dictates basic cathodes
properties.1,2 We will discuss the renaissance of Li metal-based rechargeable batteries.3
We have learned how the stabilize Li metal anodes in rechargeable batteries using
reactive electrolyte solutions that induce excellent passivation through controlled
surface reactions. The emphasis is on fluorinated co-solvents that open the door for a
very rich surface chemistry that forms passivating surface films that behave as ideal
solid electrolyte interphase on both anodes and cathodes in advanced secondary Li
batteries. This field provides fascinating examples how systematic basic scientific
work leads to development of most practical devices for energy storage & conversion. -
Date:23MondayDecember 2024Lecture
Foundations of Computer Science Seminar
More information Time 11:15 - 12:15Title On Cryptography and the Perebor ConjecturesLocation Jacob Ziskind BuildingLecturer Noam Mazor
Tel Aviv UniversityOrganizer Department of Computer Science and Applied MathematicsContact Abstract Show full text abstract about The Perebor (Russian for "brute-force search") con...» The Perebor (Russian for "brute-force search") conjectures are among the oldest conjectures in complexity theory. These conjectures, a stronger form of the P!=NP conjecture (which they predate), assert that for "meta-complexity" problems—such as the Time-Bounded Kolmogorov Complexity Problem and the Minimum Circuit Size Problem (MCSP)—no algorithms significantly outperform brute-force search.
In this talk, we will refute the non-uniform version of the Perebor conjecture for the Time-Bounded Kolmogorov Complexity Problem. Specifically, for every polynomial t(.), we will see a circuit of size 2^{4n/5+o(n)} that solves the t(.)-bounded Kolmogorov complexity problem on all instances. Along the way, and of independent interest, we will extend the Fiat-Naor result, by showing that any efficiently computable function can be inverted by a circuit of size 2^{4n/5+o(n)}.
Furthermore, we will show that, under cryptographic assumptions, Gap versions of meta-complexity problems are not NP-complete under Levin (witness-preserving) reductions. Finally, we will demonstrate how this barrier, combined with known NP-completeness results for meta-complexity problems, leads to a lower bound on the overhead of indistinguishability obfuscation (iO).
This talk is based on joint works with Zhenjian Lu, Igor C. Oliveira, and Rafael Pass. -
Date:24TuesdayDecember 2024Lecture
Winter STAR Workshop
More information Time 10:00 - 18:00Location Jacob Ziskind Building -
Date:24TuesdayDecember 2024Lecture
Anterior-Posterior Insula Circuit Mediates Retrieval of a Conditioned Immune Response in Mice
More information Time 12:30 - 13:30Location Gerhard M.J. Schmidt Lecture HallLecturer Pnina Hadad Organizer Department of Brain SciencesContact Abstract Show full text abstract about <p>The brain can form associations between sensory inf...» <p>The brain can form associations between sensory information of inner and/or outer world (e.g. Pavlovian conditioning) but also between sensory information and the immune system. The phenomenon which was described in the last century is termed conditioned immune response (CIR) but very little is known about neuronal mechanisms subserving it. The conditioned stimulus can be a given taste and the unconditioned stimulus is an agent that induces or reduces a specific immune response. Over the last years, we and others revealed molecular and cellular mechanisms underlying taste valance representation in the anterior insular cortex (aIC). Recently, a circuit in the posterior insular cortex (pIC) encoding the internal representation of a given immune response was identified. Together, it allowed us to hypothesize and prove that the internal reciprocal connections between the anterior and posterior insula encode CIR. One can look at CIR as a noon declarative form of Nocebo effect and thus we demonstrate for the first time a detailed circuit mechanism for Placebo/Nocebo effect in the cortex.</p> -
Date:25WednesdayDecember 2024Lecture
Winter STAR Workshop
More information Time 10:00 - 18:00Location Jacob Ziskind Building -
Date:25WednesdayDecember 2024Lecture
Machine Learning and Statistics Seminar
More information Time 11:15 - 12:15Title Communal AI - Open, Collaborative & Accessible LLMsLocation Jacob Ziskind BuildingLecturer Leshem Choshen
MITOrganizer Department of Computer Science and Applied MathematicsContact Abstract Show full text abstract about Developing better Language Models would benefit a myriad of ...» Developing better Language Models would benefit a myriad of communities. However, it is prohibitively costly. The talk would describe collaborative approaches to pretraining, such as model merging, which allows the combining of several specialized models into one. Then, it would introduce efficient evaluation to reduce overheads and touch on other accessible and collaborative aspects that best harness the expertise and diversity in Academia. -
Date:26ThursdayDecember 2024Cultural Events
An intimate meeting with the families of the hostages Tal Shoham and Yagev Buchshtab
More information Time 09:45 - 11:15Location Nella and Leon Benoziyo Building for Biological SciencesOrganizer Department of Molecular Cell BiologyContact -
Date:26ThursdayDecember 2024Lecture
Winter STAR Workshop
More information Time 10:00 - 18:00Location Jacob Ziskind Building -
Date:26ThursdayDecember 2024Lecture
Vision and AI
More information Time 12:15 - 13:15Title Discovering and Erasing Undesired ConceptsLocation Jacob Ziskind BuildingLecturer Niv Cohen
NYUOrganizer Department of Computer Science and Applied MathematicsContact Abstract Show full text abstract about The rapid growth of generative models allows an ever-increas...» The rapid growth of generative models allows an ever-increasing variety of capabilities. Yet, these models may also produce undesired content such as unsafe images, private information, or copyrighted material.
In this talk, I will discuss practical methods to prevent undesired generations. First, I will show how the challenge of avoiding undesired generations manifested itself in a simple Capture-the-Flag LLM setting, where even our top defense strategy was breached. Next, I will demonstrate a similar vulnerability in state-of-the-art concept erasure methods for Text-to-Image models. Finally, I will describe the notion of ‘Unconditional Concept Erasure’ aiming to mitigate such vulnerabilities. I will show that Task Vectors can achieve Unconditional Concept Erasure, and discuss the challenge of applying Task Vectors in practice.
Bio: Niv is a postdoctoral researcher at New York University hosted by Prof. Chinmay Hegde. He received a BSc in mathematics with physics as part of the Technion Excellence Program. He received his PhD in computer science from the Hebrew University of Jerusalem, advised by Prof. Yedid Hoshen. Niv was awarded the Israeli data science scholarship for outstanding postdoctoral fellows (VATAT). He is interested in anomaly detection, model personalization, and AI safety for Vision -
Date:26ThursdayDecember 2024Lecture
Deep language models as a cognitive model for natural language processing in the human brain
More information Time 12:30 - 13:30Location Gerhard M.J. Schmidt Lecture HallLecturer Prof. Uri Hasson
Special SeminarOrganizer Department of Brain SciencesContact Abstract Show full text abstract about <p>Naturalistic experimental paradigms in cognitive ne...» <p>Naturalistic experimental paradigms in cognitive neuroscience arose from a pressure to test, in real-world contexts, the validity of models we derive from highly controlled laboratory experiments. In many cases, however, such efforts led to the realization that models (i.e., explanatory principles) developed under particular experimental manipulations fail to capture many aspects of reality (variance) in the real world. Recent advances in artificial neural networks provide an alternative computational framework for modeling cognition in natural contexts. In this talk, I will ask whether the human brain's underlying computations are similar or different from the underlying computations in deep neural networks, focusing on the underlying neural process that supports natural language processing in adults and language development in children. I will provide evidence for some shared computational principles between deep language models and the neural code for natural language processing in the human brain. This indicates that, to some extent, the brain relies on overparameterized optimization methods to comprehend and produce language. At the same time, I will present evidence that the brain differs from deep language models as speakers try to convey new ideas and thoughts. Finally, I will discuss our ongoing attempt to use deep acoustic-to-speech-to-language models to model language acquisition in children. </p> -
Date:26ThursdayDecember 2024Lecture
To be announced
More information Time 15:00 - 16:00Location Nella and Leon Benoziyo Building for Biological SciencesLecturer Sonia Oren Organizer Department of Biomolecular SciencesContact -
Date:29SundayDecember 2024Lecture
Mouse cortex aligns coding of perceptual decisions to motor actions according to context
More information Time 12:00 - 13:15Location Max and Lillian Candiotty BuildingAbstract Show full text abstract about <p>How do animals make perceptual decisions about inco...» <p>How do animals make perceptual decisions about incoming sensory stimuli, like touch, smell, and sound, to guide appropriate motor actions? One hypothesis, called abstract coding, is that sensory stimuli activate action-independent "perceptual decision" cells in the cortex, but a decades-long search for such cells has so far yielded mixed results. Another hypothesis, called intentional coding, is that perceptual decisions are made by the same cells that plan the specific action, meaning the coding of perceptual decisions is action-aligned. To distinguish between these hypotheses, we designed a vibrotactile detection task for mice in which they flexibly switched between standard and reversed contingency blocks. While in the standard blocks the mice needed to lick in response to a stimulus, in the reversed blocks they needed to lick in response to the absence of a stimulus. A cortex-wide optogenetic screen revealed that somatosensory and secondary motor cortices are specifically necessary for linking stimulus to action without impairing the ability to lick. However, widefield and two-photon imaging in these and other cortical regions found that differences in activity across perceptual decisions were almost exclusively action-aligned. Our data are thus consistent with the intentional coding hypothesis for vibrotactile detection in mice but do not rule out subcortical abstract coding. At the same time, we discovered a subset of cells in the secondary motor cortex that encoded the block context. Using computational modeling, we demonstrate that this class of cells can align perceptual decision coding to specific motor actions, accounting for both contingency-dependent behavior and the results of optogenetic inhibition seen in our task.</p> -
Date:30MondayDecember 2024Lecture
Hierarchical Design Principles for Multifunctional Biocomposites
More information Time 10:00 - 11:00Lecturer Dr. Israel Kellersztein -
Date:30MondayDecember 2024Lecture
Foundations of Computer Science Seminar
More information Time 11:15 - 12:15Title Can We Bypass the Curse of Dimensionality in Private Data Analysis?Location Jacob Ziskind BuildingLecturer Eliad Tsfadia
Georgetown UniversityOrganizer Department of Computer Science and Applied MathematicsContact Abstract Show full text abstract about Differentially private (DP) algorithms typically exhibit a s...» Differentially private (DP) algorithms typically exhibit a significant dependence on the dimensionality of their input, as their error or sample complexity tends to grow polynomially with the dimension. This cost of dimensionality is inherent in many problems, as Bun, Ullman, and Vadhan (STOC 2014) showed that any method that achieves lower error rates is vulnerable to tracing attacks (also known as membership inference attacks). Unfortunately, such costs are often too high in many real-world scenarios, such as training large neural networks, where the number of parameters (the ambient dimension) is very high.
On the positive side, the lower bounds do not rule out the possibility of reducing error rates for "easy" inputs. But what constitutes "easy" inputs? And how likely is it to encounter such inputs in real-world scenarios?
In this talk, I will present a few ways to quantify "input easiness" for the fundamental task of private averaging and support them with upper and lower bounds. In particular, I will show types of properties that are both sufficient and necessary for eliminating the polynomial dependency on the dimension.
I will conclude by outlining future research directions and providing a broader perspective on my work.
The talk is mainly based on the following three papers:
(1) FriendlyCore https://arxiv.org/abs/2110.10132 (joint with Edith Cohen, Haim Kaplan, Yishay Mansour, and Uri Stemmer, ICML 2022),
(2) https://arxiv.org/abs/2307.07604 (joint with Naty Peter and Jonathan Ullman, COLT 2024),
(3) https://arxiv.org/abs/2402.06465 (NeurIPS 2024) -
Date:31TuesdayDecember 2024Lecture
Go with the flow: energetic robustness in bacterial photosynthesis
More information Time 14:00 - 15:00Location Gerhard M.J. Schmidt Lecture HallLecturer Asst. Prof. Dvir Harris Organizer Department of Chemical and Structural Biology -
Date:01WednesdayJanuary 2025Lecture
students seminar series- Azrieli
More information Time 10:30 - 12:30Location Camelia Botnar BuildingContact -
Date:02ThursdayJanuary 2025Lecture
Vision and AI
More information Time 12:15 - 13:15Title Utilizing Pre-trained Diffusion Models for Text-based Image and Video EditingLocation Jacob Ziskind BuildingLecturer Vladimir Kulikov
TechnionOrganizer Department of Computer Science and Applied MathematicsContact Abstract Show full text abstract about Text-to-image (T2I) diffusion/flow models achieve state-of-t...» Text-to-image (T2I) diffusion/flow models achieve state-of-the-art results in image synthesis. Many works leverage these models for real image editing, where a predominant approach involves inverting the image into its corresponding gaussian-like noise map. However, inversion by itself is often insufficient for structure preserving edits. In our first work in this talk, termed ‘An Edit Friendly DDPM Noise Space’ [1], we present alternative latent noise maps for denoising diffusion probabilistic models (DDPMs) that do not have a standard normal distribution. These noise maps allow for perfect reconstruction of any real image, and lead to structure preserving edits, as we exemplify in our experiments.
In our second work, we tackle the task of text-based video editing using T2I diffusion models. Here the main challenge lies in maintaining the temporal consistency of the original video during the edit. Many methods leverage explicit correspondence mechanisms, which struggle with strong nonrigid motion. In contrast, our method termed ‘Slicedit’ [2], introduces a fundamentally different approach, which is based on the observation that spatiotemporal slices of natural videos exhibit similar characteristics to natural images. Thus, the same T2I diffusion model that is normally used only as a prior on video frames, can also serve as a strong prior for enhancing temporal consistency by applying it on spatiotemporal slices. As we show Sliceditgenerates videos that retain the structure and motion of the original video without relying on explicit correspondence matching while adhering to the target text. Finally, in our most recent work, we will discuss ‘FlowEdit’ [3], a novel text-based image editing method that leverages the increasingly popular flow models without relying on inversion. Our method constructs an ODE that directly maps between the source and target distributions (corresponding to the source and target text prompts) and achieves a lower transport cost than the inversion approach. This leads to state-of-the-art results, as we illustrate with Stable Diffusion 3 and FLUX.
[1] An Edit Friendly DDPM Noise Space: Inversion and Manipulations - CVPR24’ https://arxiv.org/abs/2304.06140
[2] Slicedit: Zero-Shot Video Editing With Text-to-Image Diffusion Models Using Spatio-Temporal Slices - ICML24’ https://arxiv.org/abs/2405.12211
[3] FlowEdit: Inversion-Free Text-Based Editing Using Pre-Trained Flow Models – under review https://arxiv.org/abs/2412.08629
Bio: Vladimir Kulikov, PhD student at the Technion, under the supervision of Prof. Tomer Michaeli. Currently studying Deep Generative Models with emphasis on Computer Vision. -
Date:02ThursdayJanuary 2025Lecture
Geometric Functional Analysis and Probability Seminar
More information Time 13:30 - 14:30Title TBDLocation Jacob Ziskind BuildingLecturer Shlomo Hoory
Tel-HaiOrganizer Department of MathematicsContact