BEGIN:VCALENDAR VERSION:2.0 PRODID:icalendar-ruby CALSCALE:GREGORIAN METHOD:PUBLISH BEGIN:VTIMEZONE TZID:Europe/Vienna BEGIN:DAYLIGHT DTSTART:20260329T030000 TZOFFSETFROM:+0100 TZOFFSETTO:+0200 RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=3 TZNAME:CEST END:DAYLIGHT BEGIN:STANDARD DTSTART:20261025T020000 TZOFFSETFROM:+0200 TZOFFSETTO:+0100 RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=10 TZNAME:CET END:STANDARD END:VTIMEZONE BEGIN:VEVENT DTSTAMP:20260416T010033Z UID:696142d841dd4804203517@ist.ac.at DTSTART:20260115T093000 DTEND:20260115T104500 DESCRIPTION:Speaker: Stefano Bosco\nhosted by Georgios Katsaros\nAbstract: In this talk\, I will discuss recent advances in quantum computing with ho le-spin qubits\, focusing on planar germanium platforms. These systems pro vide electrically tunable spin properties\, occasionally) strong spin-orbi t interactions\, and compatibility with superconducting hybrid circuits\, making them well suited for scaling quantum architectures. I will highligh t new progresses in engineering the spin response in these platforms\, pro gress in fast baseband electrical control of gapless qubits\, high-fidelit y readout schemes based on Andreev qubits\, illustrating the potential of germanium-based devices for scalable quantum processors. LOCATION:Office Bldg West / Ground floor / Heinzel Seminar Room (I21.EG.101 )\, ISTA ORGANIZER:gkatsaro@ist.ac.at SUMMARY:Stefano Bosco: Quantum Computing with Germanium URL:https://talks-calendar.ista.ac.at/events/6231 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010033Z UID:68776e25ec455620825225@ist.ac.at DTSTART:20260115T110000 DTEND:20260115T120000 DESCRIPTION:Speaker: Alexander Dear\nhosted by Andela Saric\nAbstract: How do competing pathways\, surface catalysis\, and phase transitions shape se lfassembly?In this seminar\, I will first show how analytical solutions to rate laws enable mechanistic dissection of how different selfassembly pat hways compete. These solutions reveal how reaction cascades can spread fro m one system to another via crosscatalysis and crossinhibition\, providing insight into links between amyloid disorders.I will then show how applyin g precise thermodynamic reasoning to the largely experimentdriven field of protein aggregation exposes the central role of morphological defects in the selfreplication of amyloid fibrils and the influence of thirdparty sur faces in selfassembly more generally.Finally\, I will show how combining a nalytical solutions with thermodynamic reasoning reveals hidden roles of p hase transitions within protein selfassembly. Competition between fibrils and other phases leads to phenomena such as hysteresis and biochemical mem ory storage by reversible amyloids\, but can also trigger neurodegenerativ e disease. LOCATION:Office Bldg West / Ground floor / Heinzel Seminar Room (I21.EG.101 )\, ISTA ORGANIZER:cpetz@ist.ac.at SUMMARY:Alexander Dear: Hidden Mechanisms in Self-Assembly: Pathway Competi tion\, Surface Catalysis\, and Phase Transitions URL:https://talks-calendar.ista.ac.at/events/6213 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010033Z UID:6960c7d51ac45346543365@ist.ac.at DTSTART:20260119T113000 DTEND:20260119T123000 DESCRIPTION:Speaker: David Rasmussen Lolck\nhosted by Monika Henzinger\nAbs tract: Correlation clustering is a well-studied problem\, first proposed b y Bansal\, Blum\, and Chawla (2004). The input is an unweighted\, undirect ed\, simple graph. The goal is to cluster (partition) the vertices so as t o minimize the number of edges between vertices in different clusters and missing edges between vertices inside the same cluster. This problem has a wide number of applications in data mining and machine learning. We will focus on the dynamic version of this problem\, where edges are added or de leted one by one\, and the goal is to maintain a clustering during these u pdates. This talk will present a general framework that transforms existin g static correlation clustering algorithms into fully-dynamic ones that wo rk against an adaptive adversary. In this talk\, I will show how to apply the framework to known efficient static correlation clustering algorithms\ , starting from the classic 3-approximate Pivot algorithm by Ailon\, Chari kar\, and Newman (2008). Applied to the recent near-linear 1.485-approxima tion algorithm by Cao et al. (2025)\, we get a 1.485-approximation fully-d ynamic algorithm that works with worst-case constant update time. The orig inal static algorithm gets its approximation ratio with constant probabili ty\, and we get the same against an adaptive adversary. Previous dynamic a lgorithms for correlation clustering had approximation ratios around 3 in expectation against oblivious adversaries. LOCATION:Central Bldg / O1 / Mondi 2a (I01.O1.008)\, ISTA ORGANIZER:achaturv@ist.ac.at SUMMARY:David Rasmussen Lolck: TCS Talk - Static to Dynamic Correlation Clu stering URL:https://talks-calendar.ista.ac.at/events/6229 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010033Z UID:6687bf08e3e2d265502488@ist.ac.at DTSTART:20260120T161500 DTEND:20260120T171500 DESCRIPTION:Speaker: Davide Desio\nhosted by Robert Seiringer\nAbstract: Th e polaron problem\, introduced by Landau in 1933\, concerns the coupling o f an electron with phonon fields in a continuum. The energy-momentum relat ion for the Frhlich polaron has been recently proved to be a concave funct ion of the square of the total momentum with a probabilistic approach via Wiener integrals. In this talk\, I will present an abstract Dyson expansio n for form bounded perturbations and apply it to the polaron Hamiltonian. I will show that the expectation value of the heat semi-group on the vacuu m is a completely monotone function of the square of the total momentum an d\, consequently\, the concavity of the energy-momentum relation as a func tion of the square of the total momentum. LOCATION:Office Bldg West / Ground floor / Heinzel Seminar Room (I21.EG.101 )\, ISTA ORGANIZER:boosthui@ist.ac.at SUMMARY:Davide Desio: A rigorous Dyson expansion for polaron Hamiltonians URL:https://talks-calendar.ista.ac.at/events/6237 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010033Z UID:6960d83c4ccf7738233065@ist.ac.at DTSTART:20260121T133000 DTEND:20260121T143000 DESCRIPTION:Speaker: Ravi Venkatramani\nhosted by Latha Venkataraman\nAbstr act: Our research group develops robust\, systematic and statistical descr iptions of diverse physicochemical phenomena in molecular and biomolecular systems. I will present three new conceptual ideas that have emerged thro ugh our efforts in last decade. In the first part of this seminar\, I will introduce electronic molecular breadboards as a framework for prototyping circuits within experimental break-junction setups. Here\, conductance hi stograms serve as statistical fingerprints of circuit pathways. Our new co mputational models that simulate these histograms\, enable experimental ac cess to embedded circuits and highlight how statistical descriptions can g uide the design of complex functional molecular circuits.Next\, I will tur n to the discovery of protein charge transfer spectra (ProCharTS)\, which explains puzzling but consistent detection of non-aromatic UV-vis absorpti on/emission. Overturning textbook paradigms\, we have shown that ProCharTS arises from to charge-transfer transitions within clusters of charged ami no acids. Using Time-Dependent Density Functional Theory (TDDFT) on statis tical ensembles of charged amino acid clusters\, I will show how such nove l spectra can be simulated and predicted. ProCharTS opens up a new label-f ree optical mode to track biologically relevant processes such as post-tra nslational modifications and biomolecular interactions.Finally\, I will ad dress the problem of quantitatively sampling rugged biomolecular energy la ndscapes in in Molecular Dynamics (MD) simulations. Specifically\, the int roduction of the cumulative variance of coordinate fluctuations (CVCF) as a parameter-free metric to identify Boltzmann-sampled regions of trajector ies\, and the mode evolution metric (MEM) to detect locally converged dire ctions toward hidden metastable states. These new statistical ideas are in tegrated into AutoSIM\, a software which discovers reaction coordinates an d then extracts energy landscapes governing biomolecular transitions. LOCATION:Sunstone Bldg / Ground floor / Big Seminar Room A / 27 seats (I23. EG.102)\, ISTA ORGANIZER:rpacarad@ist.ac.at SUMMARY:Ravi Venkatramani: Statistical Descriptions of Molecular Phenomena: Circuits\, Spectra\, and Dynamics URL:https://talks-calendar.ista.ac.at/events/6234 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010033Z UID:1769158800@ist.ac.at DTSTART:20260123T100000 DTEND:20260123T110000 DESCRIPTION:Speaker: Marten Chaillet\nhosted by Alicia Michael\nAbstract: C ryo-electron tomography (cryo-ET) is used to visualize complex cellular en vironments at macromolecular resolution. However\, due to limitations of t he microscope\, computational image alignment is crucial for data interpre tation. Existing reference-free alignment algorithms aim to maximize simil arity between adjacent tilt images for improved registration. This often p roves ineffective due to limited information overlap between images and in accurate assumptions about the sample. Meanwhile\, human experts can easil y recognize misalignment. We introduce a new machine learning-based approa ch for training similar intuition and using it to improve alignment. MissA lignment trains a convolutional neural network to score the alignment accu racy using a contrastive loss metric that doesn’t require well-aligned g round truth. Back-propagation from this score is then used to optimize ind ividual image alignment parameters. Our method demonstrates significantly improved alignment compared to existing techniques\, leading to superior p erformance in all downstream analysis tasks. This advancement substantiall y enhances the robustness of cryo-ET data processing\, making the techniqu e applicable to a broader range of samples. LOCATION:Office Bldg West / Ground floor / Heinzel Seminar Room\, ISTA ORGANIZER:alicia.michael@ista.ac.at SUMMARY:Marten Chaillet: MissAlignment learns to straighten out cryo-ET til t series URL:https://talks-calendar.ista.ac.at/events/6230 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010033Z UID:1769508000@ist.ac.at DTSTART:20260127T110000 DTEND:20260127T120000 DESCRIPTION:Speaker: Robin Kaiser\nhosted by Julian Leonard\nAbstract: Abst ract:The quest for Anderson localization of light is at the center of many experimental and theoretical activities. Cold atoms have emerged as inter esting quantum system to study coherent transport properties of light. Ini tial experiments have established that dilute samples with large optical t hickness allow studying weak localization of light\, which has been well d escribed by a mesoscopic model. Recent experiments on light scattering wit h cold atoms have shown that Dicke super- or subradiance occurs in the sam e samples\, a feature not captured by the traditional mesoscopic models. T he use of a long range microscopic coupled dipole model allows to capture both the mesoscopic features of light scattering and Dicke super- and subr adiance in the single photon limit. I will review experimental and theoret ical state of the art on the possibility of Anderson localization of light in 3D by cold atoms. LOCATION:Heinzel Seminar Room\, ISTA ORGANIZER: SUMMARY:Robin Kaiser: Resonant optical dipole-dipole interactions in cold a toms URL:https://talks-calendar.ista.ac.at/events/6161 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010033Z UID:1769680800@ist.ac.at DTSTART:20260129T110000 DTEND:20260129T120000 DESCRIPTION:Speaker: Matthew Houtput\nhosted by Mikhail Lemeshko\nAbstract: Electron-phonon interactions are often written using the approximation of linear interaction\, where one only keeps the process where one electron interacts with one phonon. This is usually sufficient to quantitatively de scribe material properties. However\, this is no longer true in anharmonic materials with significant electron-phonon interaction\, such as quantum paraelectrics and halide perovskites. Currently\, the only available model s for nonlinear electron-phonon interaction are model Hamiltonians\, writt en in terms of phenomenological parameters. Here\, we provide a microscopi c semi-analytical expression for the long-range dipole part of the 1-elect ron-2-phonon matrix element\, which can be interfaced with first principle s techniques. We show that unlike for the long-range 1-electron-1-phonon i nteraction\, the continuum approximation is not sufficient and that the en tire phonon dispersion must be considered. We calculate an expression for the quasiparticle energies and show that they can be written in terms of a 1-electron-2-phonon spectral function. To demonstrate the method in pract ice\, we calculate the 1-electron-2-phonon spectral function for LiF and C sPbI3 from first principles\, and we show that the nonlinear interaction c ontributes significantly to the electron mobility of CsPbI3. The framework presented here bridges the gap between model Hamiltonians and first-princ iples calculations for the 1-electron-2-phonon interaction. LOCATION:Office Bldg West / Ground floor / Foyer seminar room \, ISTA ORGANIZER:Michaela.Pucher@ist.ac.at SUMMARY:Matthew Houtput: First principles theory of nonlinear long-range el ectron-phonon interaction URL:https://talks-calendar.ista.ac.at/events/6255 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010033Z UID:6964a817f3eba980251668@ist.ac.at DTSTART:20260129T130000 DTEND:20260129T140000 DESCRIPTION:Speaker: Richard Wong\nhosted by Martin Loose\nAbstract: Biomol ecular dynamics govern cellular architecture\, homeostasis\, and adaptive responses to environmental stress. While structural biology has been trans formative in defining molecular form and function\, many essential process es are driven by transient and mechanically coupled dynamics that remain d ifficult to capture. Cryo-EM and X-ray crystallography provide exquisite s tructural detail but are limited in temporal resolution and often require non-physiological conditions\, whereas spectroscopic approaches such as FR ET and NMR lack direct real-time visualization of structural transitions. High-speed atomic force microscopy (HS-AFM) bridges this gap by enabling r eal-time nanoimaging of biomolecular dynamics under near-physiological con ditions with high spatiotemporal resolution and minimal perturbation. In t his talk\, I will show how HS-AFM moves us beyond static snapshots toward living structural landscapes\, focusing on nuclear pore complexes (NPCs)\, chromatin organization\, microtubule dynamics\, and extracellular vesicle s. Our work reveals that NPCs are highly dynamic\, mechanically adaptive a ssemblies that regulate nucleocytoplasmic transport while shaping perinucl ear chromatin architecture. HS-AFM captures transient interactions between NPCs and chromatin-associated proteinsgenome guardians coordinating trans cription\, DNA repair\, and stress responses. Extending this dynamic view to cytoskeletal systems\, we also visualize asymmetric protofilament failu re and spontaneous rescue events during microtubule disassembly\, revealin g unexpected stabilization mechanisms. Conceptually\, this nanoscale persp ective aligns with active-matter studies showing how single-filament prope rtiessuch as flexibility\, density\, and chiralitygovern emergent mesoscop ic order\, exemplified by chiral and nematic phase transitions in reconsti tuted cytoskeletal filaments. Together\, these findings demonstrate how na noscale dynamics at organelle and filament interfaces integrate transport\ , genome regulation\, and cytoskeletal remodeling\, providing a framework for understanding disease-relevant processes in cancer\, neurodegeneration \, infertility\, and viral infection. LOCATION:Moonstone Bldg / Ground floor / Seminar Room G (I24.EG.030g)\, IST A ORGANIZER:mloose@ist.ac.at SUMMARY:Richard Wong: Zooming Through the Cellular Labyrinth: Journeys to t he Nuclear Pore and Chromatin URL:https://talks-calendar.ista.ac.at/events/6239 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010033Z UID:1770717600@ist.ac.at DTSTART:20260210T110000 DTEND:20260210T120000 DESCRIPTION:Speaker: Marco David\nhosted by Maksym Serbyn\nAbstract: Abstra ct: Today’s gold standard for establishing new theoretical results in ma thematics is an accompanying formal computer-verification of the theorems and their proofs. Interactive theorem provers (ITPs)—originally designed to verify computer algorithms—are now gaining significant traction in m athematical research. Systems such as Isabelle\, Coq\, and Lean provide pr ogramming languages that mechanize reasoning and thereby allow the verific ation of proofs. In 2024\, Google DeepMind used reinforcement learning in such a formal language to win a silver medal at the International Mathemat ics Olympiad for the first time. The potential of formal methods in quant um theory remains under-explored. In this talk\, I will introduce a provoc atively titled list of the “top 100” quantum theorems\, aimed at gamif ying and popularizing the formal verification of quantum theory. Building such a quantum library will provide a unified\, searchable and cross-linke d database of formalized mathematical knowledge. This can also allow train ing artificial intelligence models in an environment where precise details matter. https://marcodavid.net/top100/  LOCATION:Office Bldg West / Ground floor / Heinzel Seminar Room (I21.EG.101 )\, ISTA ORGANIZER:Stephanie.Dolot@ist.ac.at SUMMARY:Marco David: QED. The Quest to Formalize Physics. URL:https://talks-calendar.ista.ac.at/events/6265 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010033Z UID:6973503e778d2133173368@ist.ac.at DTSTART:20260210T110000 DTEND:20260210T120000 DESCRIPTION:Speaker: Jens Elgeti\nhosted by Edouard Hannezo\nAbstract: Mech anical forces influence cellular decisions to grow\, die\, or differentiat e\, through largely mysterious mechanisms. Separately\, changes in resting membrane potential have been observed in development\, differentiation\, regeneration\, and cancer. We demonstrate that membrane potential is an im portant mediator of cellular response to mechanical pressure. We show that mechanical forces acting on the cell change cellular biomass density\, wh ich\, in turn\, alters membrane potential. Membrane potential then regulat es cell number density in epithelia by controlling cell growth\, prolifera tion\, and cell elimination. I will present the experimental evidence that lead to the discovery\, but mainly focus on the physical mechanism based on osmotic stresses and charge balance. I will introduce simulations based on this mechanism\, and show their predictions and experimental verificat ion.[1] Mukherjee\, Huang\, Elgeti\, Basan. Cell 189\, 143 (2026) LOCATION:Sunstone Bldg / Ground floor / Big Seminar Room B / 63 seats (I23. EG.102)\, ISTA ORGANIZER:cpetz@ist.ac.at SUMMARY:Jens Elgeti: Membrane potential mediates the cellular response to m echanical pressure – insights from simulations URL:https://talks-calendar.ista.ac.at/events/6271 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010033Z UID:698454fd67a8f977124952@ist.ac.at DTSTART:20260210T161500 DTEND:20260210T171500 DESCRIPTION:Speaker: Rupert Frank\nhosted by Robert Seiringer\nAbstract: Th e CCM equation (also known as CalogeroMoser derivative nonlinear Schrdinge r equation) is a nonlinear dispersive equation in 1+1 dimensions that is c ompletely integrable. The corresponding Lax operator is a first order oper ator in the Hardy space on the real line. We develop a spectral theory of this operator\, building Jost solutions\, proving absence of singularly co ntinuous spectrum and introducing scattering coefficients. We also prove t race formulas of Birman-Krein and Faddeev-Zakharov type. Finally\, we prop ose an inverse scattering scheme for the solution of the CCM equation.The talk does not assume any previous knowledge of the CCM equation. It is bas ed on joint work with Larry Read. LOCATION:Office Bldg West / Ground floor / Heinzel Seminar Room (I21.EG.101 )\, ISTA ORGANIZER:boosthui@ist.ac.at SUMMARY:Rupert Frank: Direct and inverse scattering for the continuum Calog ero-Moser equation URL:https://talks-calendar.ista.ac.at/events/6281 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010033Z UID:6687bf08e3e40031366181@ist.ac.at DTSTART:20260210T171500 DTEND:20260210T181500 DESCRIPTION:Speaker: Jonas Jalowy\nhosted by Andrew Campbell\nAbstract: The guiding question of the talk is "How do zeros of polynomials evolve under the action of differential operators?"For instance\, taking a Weyl random polynomial and applying the heat flow operator\, the (complex) limiting z ero distribution evolves from the circular law into the elliptic law until it collapses to the Wigner semicircle law--a transition that is well know n in Random Matrix Theory.In this talk\, I will focus on the case of polyn omials undergoing the (holomorphic) heat flow operator and begin with an o verview on results of such type as well as a description of the roots from various points of view such as (optimal) transport\, differential equatio ns and free probability. Then\, we will turn to a specific deterministic s etting of polynomial powers P^n\, where a novel limiting distribution can be described along the time evolution: For small time\, the initial zeros spread out in approximately semicircular distributions\, then intricate cu rves start to form and merge\, until for large time\, the zero distributio n approaches a semicircle law through the initial center of mass.This talk is based on joint works with Brian Hall\, Ching-Wei Ho\, Antonia Hfert\, Zakhar Kabluchko\, and Alexander Marynych. LOCATION:Office Bldg West / Ground floor / Heinzel Seminar Room (I21.EG.101 )\, ISTA ORGANIZER:boosthui@ist.ac.at SUMMARY:Jonas Jalowy: Evolution of zeros of polynomials under the heat flow URL:https://talks-calendar.ista.ac.at/events/6280 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010033Z UID:6964b0d50ce98040791463@ist.ac.at DTSTART:20260211T111500 DTEND:20260211T121500 DESCRIPTION:Speaker: Emily Davis\nhosted by Onur Hosten\nAbstract: Spin squ eezed states provide a seminal example of how the structure of quantum mec hanical correlations can be controlled to produce metrologically useful en tanglement. Such squeezed states have been demonstrated in a wide variety of artificial quantum systems ranging from atoms in optical cavities to tr apped ion crystals. By contrast\, despite their numerous advantages as pra ctical sensors\, spin ensembles in solid-state materials have yet to be co ntrolled with sufficient precision to generate targeted entanglement such as spin squeezing. In this work\, we present the first experimental demons tration of spin squeezing in a solid-state spin system. Our experiments ar e performed on a strongly-interacting ensemble of nitrogen-vacancy (NV) co lor centers in diamond at room temperature and squeezing (-0.5 pm 0.1 dB) is generated by the native magnetic dipole-dipole interaction between NVs. In order to generate and detect squeezing in a solid-state spin system\, we overcome a number of key challenges of broad experimental and theoretic al interest. First\, we develop a novel approach\, using interaction-enabl ed noise spectroscopy\, to characterize the quantum projection noise in ou r system without directly resolving the spin probability distribution. Sec ond\, noting that the random positioning of spin defects severely limits t he generation of spin squeezing\, we implement a pair of strategies aimed at isolating the dynamics of a relatively ordered sub-ensemble of NV cente rs. Our results open the door to entanglement-enhanced metrology using mac roscopic ensembles of optically-active spins in solids. LOCATION:Office Bldg West / Ground floor / Heinzel Seminar Room (I21.EG.101 )\, ISTA ORGANIZER:swiddman@ist.ac.at SUMMARY:Emily Davis: Spin squeezing in an ensemble of nitrogen-vacancy cent ers in diamond URL:https://talks-calendar.ista.ac.at/events/6240 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010033Z UID:1771341300@ist.ac.at DTSTART:20260217T161500 DTEND:20260217T180000 DESCRIPTION:Speaker: Joscha Henheik\nhosted by László Erdös \nAbstract: Abstract: In nature one finds superconductors of varying critical temperat ures and energy gaps. For weak superconductors\, where the critical temper ature is small\, a universal phenomenon occurs: The ratio of the energy ga p and critical temperature is a universal value\, independent of the speci fic superconductor. I will present recent work on such universal phenomena in the BCS theory of superconductivity.Based on joint works with A. B. La uritsen\, E. Langmann\, and B. Roos.  LOCATION:Office Bldg West / Ground floor / Heinzel Seminar Room (I21.EG.101 )\, ISTA ORGANIZER:Birgit.Oosthuizen-Noczil@ist.ac.at SUMMARY:Joscha Henheik: Universalities in BCS theory URL:https://talks-calendar.ista.ac.at/events/6290 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010033Z UID:1771502400@ist.ac.at DTSTART:20260219T130000 DTEND:20260219T140000 DESCRIPTION:Speaker: Ivana Matijevic\nAbstract: Understanding what sets the timing of cellular activation remains a central challenge in dynamic sign aling systems. Rab5 activation on membranes emerges from a feedback-drive n\, threshold-controlled process shaped by catalytic input\, substrate ava ilability\, and spatial confinement. Here\, we probe how spatial scale in teracts with inhibitory (GDI) and activating mechanisms (RR) to shape tem poral responses. By systematically varying these parameters\, we aim to b etter understand their roles and uncover how Rab5 activation emerges fro m coupled spatial and biochemical input.  LOCATION:Central Bldg / O1 / Mondi 2a&b\, ISTA ORGANIZER:rita.pacarada@ist.ac.at SUMMARY:Ivana Matijevic: When Biochemistry Meets Geometry: Spatial and Bioc hemical Determinants of Rab5 Activation URL:https://talks-calendar.ista.ac.at/events/6285 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010033Z UID:1771578000@ist.ac.at DTSTART:20260220T100000 DTEND:20260220T110000 DESCRIPTION:Speaker: Fidel Emmanuel Serrano\nhosted by Alicia Michael\nAbst ract: The mammalian circadian clock is governed by a feedback loop in whic h the transcription activator CLOCK:BMAL1 induces expression of its inhibi tors\, PERs and CRYs\, which form a complex with CK1δ\, the main circadia n kinase. However\, the spatiotemporal dynamics of this feedback loop and the precise role of CK1δ remain incompletely understood. Using an inducib le overexpression system\, we show that nuclear availability of CK1δ is l imited by both rapid nuclear degradation and active export of unassembled kinase\, while cytoplasmic kinase is readily available for association wit h PERs. We demonstrate that CK1δ-mediated phosphorylation may disrupt PER 2-CRY1 interaction thereby resulting in cytoplasmic PER2 dimers containing substoichiometric amounts of CRY1. Analysis of endogenous PER2 localizati on in the context of an intact circadian clock reveals that PER2 accumulat es in the cytoplasm late in the circadian cycle. Based on these findings\, we propose that cytoplasmic accumulation of PER:CRY:CK1δ complexes contr ibutes to the clearance of nuclear PER2\, while the CK1δ-dependent releas e of CRY1 into the nucleus may sustain CLOCK:BMAL1 repression on DNA suppo rting the transition from the early to the late repressive phase. LOCATION:Moonstone Bldg / Ground floor / Seminar Room E\, ISTA ORGANIZER:alicia.michael@ista.ac.at SUMMARY:Fidel Emmanuel Serrano: Nuclear CK1δ as a Critical Determinant of PER:CRY Complex Dynamics and Circadian Period URL:https://talks-calendar.ista.ac.at/events/6291 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010033Z UID:6995914c27acd107259767@ist.ac.at DTSTART:20260225T110000 DTEND:20260225T121500 DESCRIPTION:Speaker: Alfonso Martinez Arias\nhosted by Edouard Hannezo LOCATION:Raiffeisen Lecture Hall\, Central Building\, ISTA ORGANIZER:cpetz@ist.ac.at SUMMARY:Alfonso Martinez Arias: A pluripotent stem cell view of gastrulatio n URL:https://talks-calendar.ista.ac.at/events/6305 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010033Z UID:698f1a0aaf212263034654@ist.ac.at DTSTART:20260226T113000 DTEND:20260226T123000 DESCRIPTION:Speaker: Nikita Kalinin\nAbstract: The lower-triangular all-one s counting matrix is a key primitive in differential privacy\, and its fac torization norms determine theoretical utility guarantees for private mach ine learning training with correlated noise. For more than three decades\, the best known upper bound for these norms remained essentially unchanged \, and recent work asked whether an explicit factorization could provably improve it. In this talk I present an explicit\, efficiently computable co nstruction that improves the longstanding bound\, together with significan tly stronger lower bounds\, shrinking the remaining constant gap to a smal l margin. LOCATION:Office Bldg West / Ground floor / Foyer seminar room (I21.EG.128)\ , ISTA ORGANIZER:achaturv@ist.ac.at SUMMARY:Nikita Kalinin: TCS Seminar - Sharper Matrix Factorization Bounds f or Differentially Private Continual Counting URL:https://talks-calendar.ista.ac.at/events/6298 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010033Z UID:691214567bfbd513487778@ist.ac.at DTSTART:20260302T160000 DTEND:20260302T170000 DESCRIPTION:Speaker: Yujin Kim\nhosted by Laszlo Erdös & Jan Maas\nAbstrac t: Gaussian multiplicative chaos (GMC) is a well-studied random measure ap pearing as a universal object in the study of Gaussian or approximately Ga ussian log-correlated fields. On the other hand\, no general framework exi sts for the study of multiplicative chaos associated to non-Gaussian log-c orrelated fields. In this talk\, we examine a canonical model: the log-cor related random Fourier series\, or random wave model\, with i.i.d. random coefficients taken from a general class of distributions. The associated m ultiplicative chaos measure was shown to be non-degenerate when the invers e temperature is subcritical ($\\gamma < \\sqrt{2d}$) by Junnila. The resu lting chaos is easily seen to not be a GMC in general\, leaving open the q uestion of what properties are shared between this non-Gaussian chaos and GMC. We answer this question through the lens of absolute continuity\, sho wing that there exists a coupling between this chaos and a GMC such that t he two are almost surely mutually absolutely continuous. LOCATION:Central Bldg / O1 / Mondi 2a (I01.O1.008)\, ISTA ORGANIZER:birgit.oosthuizen-noczil@ist.ac.at SUMMARY:Yujin Kim: Absolute continuity of non-Gaussian and Gaussian multipl icative chaos measures URL:https://talks-calendar.ista.ac.at/events/6323 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010033Z UID:69a187fcbb1eb211020820@ist.ac.at DTSTART:20260302T170000 DTEND:20260302T180000 DESCRIPTION:Speaker: Tom Hutchcroft\nhosted by Laszlo Erdös & Jan Maas\nAb stract: It is conjectured that many models of statistical mechanics have a rich\, fractal-like behaviour at and near their points of phase transitio n\, with power-law scaling governed by critical exponents that are expecte d to depend on the dimension but not on the small-scale details of the mod el such as the choice of lattice. This is now reasonably well understood i n two dimensions and in high dimensions\, but remains poorly understood in intermediate dimensions (e.g. d=3). I will overview the conjectures aroun d this area and describe recent progress on related problems for models wi th long-range interactions. LOCATION:Central Bldg / O1 / Mondi 2a (I01.O1.008)\, ISTA ORGANIZER:boosthui@ist.ac.at SUMMARY:Tom Hutchcroft: Critical long-range percolation URL:https://talks-calendar.ista.ac.at/events/6324 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010033Z UID:1772532000@ist.ac.at DTSTART:20260303T110000 DTEND:20260303T120000 DESCRIPTION:Speaker: Lincoln Carr\nhosted by Maksym Serbyn\nAbstract: Abstr act: One-dimensional Quantum cellular automata (QCA) in quantum circuits provide an experimentally realizable quantum computing testbed for quantum entangled dynamics\, spanning both integrable and quantum many-body chaot ic extremes.  In this work\, we establish a quantum many-body Kolmogorov- Arnold-Moser (KAM) framework in 1D QCA\, characterizing the breakdown of i ntegrability through a state-dependent hierarchy of conservation laws. Sta rting from the integrable limit of Goldilocks rules that map exactly onto free-fermion dynamics\, we introduce controlled\, locality-preserving pert urbations via symmetric Strang splitting. We investigate the breakdown of integrability by tracking the deformation of the first 13 local conserved charges directly within the native discrete-time circuit dynamics.Our cent ral finding in the circuit picture is the emergence of a stability hierarc hy of charges  determined by the algebraic structure of the perturbation generator\, classified into three distinct tiers: (i) robust invariants wh ich remain exactly conserved independent of perturbation strength\; (ii) r esonant actions which drift immediately at first order\; and (iii) KAM-lik e candidates\, in particular . We identify  as weakly non-resonant: it ex hibits anomalous super-delayed deformation under general initial condition s but remains conserved when initialized in an eigenstate of a specific Ab elian charge subset.Complementing this study of quantum circuits in discre te time\, we demonstrate rigorously that the associated continuous-time QC A Hamiltonian --- constructed via projector embeddings --- defines a funda mentally distinct dynamical system\, conserving only an Abelian subclass o f the 13 first charges from Goldilocks QCA.  Within this QCA-like Hamilto nian model\, we characterize the broader phenomenology of the integrabilit y-to-chaos crossover. We observe a universal transition from Poisson to Wi gner-Dyson spectral statistics and analyze the power-law growth of out-of- time-ordered correlators. Furthermore\, using Hamiltonian-based charge aut ocorrelators\, we map the stability of  to a regime of “confined chaos\ ,” where algebraic symmetries shield specific Hilbert space sectors from rapid thermalization\, providing a continuous-time counter-part of the KA M stability observed in the discrete circuit.References: Marc Andrew Valde z\, Daniel Jaschke\, David L. Vargas and Lincoln D. Carr\, “Quantifying Complexity in Quantum Phase Transitions via Mutual Information Complex Net works\,” Phys. Rev. Lett.\, v. 119\, p. 225301 (2017)Bhuvanesh Sundar\, Marc Andrew Valdez\, Lincoln D. Carr\, and Kaden R. A. Hazzard\, “A comp lex network description of thermal quantum states in the Ising spin chain\ ,” Phys. Rev. A\, v. 97\, p. 052320 (2018)Bhuvanesh Sundar\, Mattia Wals chaers\, Valentina Parigi\, and Lincoln D Carr\, “Response of quantum sp in networks to attacks\,” J. Phys. Complexity\, v.2\, p. 035008 (2021)LE Hillberry\, MT Jones\, DL Vargas\, P Rall\, N Yunger Halpern\, N Bao\, S Notarnicola\, S Montangero\, LD Carr\, “Entangled quantum cellular autom ata\, physical complexity\, and Goldilocks rules\,” Quantum Science and Technology\, v. 6\, p. 045017 (2021)EB Jones\, LE Hillberry\, MT Jones\, M Fasihi\, P Roushan\, Z Jiang\, A Ho\, C Neill\, E Ostby\, P Graf\, E Kapi t\, and LD Carr\, “Small-world complex network generation on a digital q uantum processor\,” Nature Communications v. 13\, p. 4483 (2022)Mattia W alschaers\, Nicholas Treps\, Bhuvanesh Sundar\, Lincoln D Carr\, and Valen tina Parigi\, “Emergent complex quantum networks in continuous-variables non-Gaussian states\,” Quantum Science and Technology\, v. 8\, p. 03500 9 (2023)LE Hillberry\, M Fasihi\, L Piroli\, N Yunger Halpern\, T Prosen\, and LD Carr\, “Classical simulability\, thermodynamics\, and integrabil ity of Goldilocks quantum cellular automata\,” Quantum Science and Techn ology\, under review\, arXiv:2404.02994 (2024)P Patnaik\, LE Hilberry\, T Prosen\, and LD Carr\, “Entanglement Dynamics of Integrable and Chaotic Quantum Cellular Automata: Towards a Quantum Many-body Kolmogorov-Arnold-M oser Theory\,” In preparation (2026)  LOCATION:Office Bldg West / Ground floor / Heinzel Seminar Room (I21.EG.101 )\, ISTA ORGANIZER:Stephanie.Dolot@ist.ac.at SUMMARY:Lincoln Carr: Entanglement Dynamics of Integrable and Chaotic Quant um Cellular Automata: Towards a Quantum Many-body Kolmogorov-Arnold-Moser Theory URL:https://talks-calendar.ista.ac.at/events/6131 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010033Z UID:699c1168a3e99368223411@ist.ac.at DTSTART:20260305T113000 DTEND:20260305T123000 DESCRIPTION:Speaker: Joel Daniel Andersson\nAbstract: We study differential ly-private statistics in the fully dynamic continual observation model\, w here many updates can arrive at each time step\, and updates to a stream c an involve both insertions and deletions of an item. Earlier work (e.g.\, Jain et al.\, NeurIPS 2023 for counting distinct elements\; Raskhodnikova & Steiner\, PODS 2025 for triangle counting with edge updates) reduced the respective cardinality estimation problem to continual counting on the di fference stream associated with the true function values on the input stre am.In such reductions\, a change in the original stream can cause many cha nges in the difference stream.This poses a challenge for applying private continual counting algorithms to obtain optimal error bounds.Our work impr oves the accuracy of several such reductions by studying the induced neigh boring relation more closely.The improvement stems from tight analysis of known factorization mechanisms for the prefix-sum matrix in this setting. In particular\, we show how the square-root factorization (Henzinger et al .\, SODA 2023\; Fichtenberger et al.\, ICML 2023) can be employed to give concrete improvements in accuracy over past work based on the binary tree mechanism.We instantiate our framework for the problems of counting distin ct elements\, estimating degree histograms\, and estimating triangle count s (under a slightly relaxed privacy model)\, showing improved accuracy for a large range of parameters.Based on joint work with Palak Jain and Satch it Sivakumar (https://arxiv.org/abs/2601.02257). LOCATION:Moonstone Bldg / Ground floor / Seminar Room G (I24.EG.030g)\, IST A ORGANIZER:achaturv@ist.ac.at SUMMARY:Joel Daniel Andersson: Improved Accuracy for Private Continual Card inality Estimation in Fully Dynamic Streams via Matrix Factorization URL:https://talks-calendar.ista.ac.at/events/6318 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010033Z UID:665dbdca8cda4207092114@ist.ac.at DTSTART:20260305T130000 DTEND:20260305T150000 DESCRIPTION:Speaker: Elsa Maneval\nhosted by Tamas Hausel\nAbstract: I will first introduce the moduli spaces of Higgs bundles that appear in the Hau sel-Thaddeus topological mirror symmetry conjecture\, present the context\ , the different proofs and possible generalisations. In particular I will explain the p-adic integration approach of Groechenig\, Wyss and Ziegler. Finally\, I will present my result\, which is a generalisation beyond the coprime case of the key intermediate step of this approach\, which we call a non-archimedean topological mirror symmetry. LOCATION:Office Bldg West / Ground floor / Heinzel Seminar Room (I21.EG.101 )\, ISTA ORGANIZER:boosthui@ist.ac.at SUMMARY:Elsa Maneval: Mirror symmetry for Higgs bundles URL:https://talks-calendar.ista.ac.at/events/6270 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010033Z UID:1773154800@ist.ac.at DTSTART:20260310T160000 DTEND:20260310T170000 DESCRIPTION:Speaker: János Pach\nhosted by Matthew Kwan\nAbstract: The cro ssing number cr(G) of a graph G\, is defined as the smallest number of crossing points between the edges of G in the best drawing of G in the plane. There is another\, equally natural\, parameter: the pair-crossing number\, denoted by pair-cr(G). This is the smallest number of crossing p airs of edges in an optimal drawing. Obviously\, we have pair-cr(G)≤cr( G)\, for every graph G. But are these two numbers always equal?  LOCATION:Raiffeisen Lecture Hall\, Central Building\, ISTA ORGANIZER:Stephanie.Dolot@ist.ac.at SUMMARY:János Pach: The crossing number conundrum URL:https://talks-calendar.ista.ac.at/events/6332 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010033Z UID:1773158400@ist.ac.at DTSTART:20260310T170000 DTEND:20260310T180000 DESCRIPTION:Speaker: Matthew Jenssen\nhosted by Matthew Kwan\nAbstract: Abs tract:The classical sphere packing problem asks: what is the densest possi ble arrangement of identical\, non-overlapping spheres in Euclidean space? Over the past century\, sphere packings have been intensely studied by ma thematicians\, physicists and computer scientists alike. The interaction b etween these perspectives has been remarkably fruitful\, yielding new insi ghts into the nature of packings and many related problems. In this talk I will survey these viewpoints\, discuss recent advances\, and highlight co nnections to combinatorics along the way.  LOCATION:Raiffeisen Lecture Hall\, Central Building\, ISTA ORGANIZER:Stephanie.Dolot@ist.ac.at SUMMARY:Matthew Jenssen: Perspectives on Sphere Packing URL:https://talks-calendar.ista.ac.at/events/6310 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010033Z UID:6993268eef1f6760206996@ist.ac.at DTSTART:20260311T110000 DTEND:20260311T120000 DESCRIPTION:Speaker: Matthijs de Jong\nhosted by Johannes Fink\nAbstract: T he Casimir force follows from quantum fluctuations of the electromagnetic field and yields a nonlinear attractive force between closely spaced condu ctive objects. Its magnitude depends on the conductivity of the objects up to optical frequencies. Measuring the Casimir force between superconducto rs should allow to isolate frequency-specific contributions to the Casimir effect\, as frequencies below the superconducting gap energy are expected to contribute differently than those above it. There is significant inter est in this contribution as it is suspected to contribute to an unexplaine d discrepancy between predictions and measurements of the Casimir force be tween normal metals\, which questions the basic principles on which estima tes of the magnitude are based. We have observed the Casimir force between superconducting objects through the nonlinear dynamics it imparts to a su perconducting drum resonator in a microwave optomechanical system. There i s excellent agreement between the experiment and Casimir force magnitude f or this device across three orders of magnitude of displacement. Furthermo re\, the Casimir nonlinearity is intense enough that\, with a modified des ign\, this device type should operate in the single-phonon nonlinear regim e. Accessing this regime has been a long-standing goal that would greatly facilitate quantum operations of mechanical resonators. LOCATION:Office Bldg West / Ground floor / Heinzel Seminar Room (I21.EG.101 )\, ISTA ORGANIZER:swiddman@ist.ac.at SUMMARY:Matthijs de Jong: Measurement of the Casimir force between supercon ductors URL:https://talks-calendar.ista.ac.at/events/6294 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010033Z UID:665dbdca8de8d819167394@ist.ac.at DTSTART:20260312T130000 DTEND:20260312T150000 DESCRIPTION:Speaker: Xujia Chen\nhosted by Tamas Hausel\nAbstract: I will g ive an introduction of what the Fulton-MacPherson compactified configurati on spaces are\, and how people use them to study embedding spaces between manifolds (for example\, the space of knots\, or diffeomorphism groups). In the second part\, I will talk about some generalization of configuratio n spaces.  LOCATION:Office Bldg West / Ground floor / Heinzel Seminar Room (I21.EG.101 )\, ISTA ORGANIZER:boosthui@ist.ac.at SUMMARY:Xujia Chen: Configuration spaces\, their usage\, and a generalizati on URL:https://talks-calendar.ista.ac.at/events/6340 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010033Z UID:69a04ff97f19f809141205@ist.ac.at DTSTART:20260312T133000 DTEND:20260312T143000 DESCRIPTION:Speaker: Antoine El-Hayek\nAbstract: In population protocols\, n different agents\, which one can think of as tiny mobile computers with limited memory\, run an algorithm to try and solve a particular problem\, using pairwise interactions. Consider the relative majority problem: each agent is given an opinion among k many\, the agents have to compute the op inion that is the most represented. In this talk\, we will run an algorith m that solves the relative majority problem: I will ask each of you to pla y the role of an agent\, and we will run the algorithm collectively and ch aotically. Expect to move around\, interact with each other\, and not do a lot of sitting down. This will show how stable this surprising algorithm is to different parameters\, including human error. LOCATION:Moonstone Bldg / Ground floor / Seminar Room G (I24.EG.030g)\, IST A ORGANIZER:achaturv@ist.ac.at SUMMARY:Antoine El-Hayek: Interactive TCS Seminar URL:https://talks-calendar.ista.ac.at/events/6339 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010034Z UID:6687bf08e3e62490445508@ist.ac.at DTSTART:20260317T161500 DTEND:20260317T171500 DESCRIPTION:Speaker: Diwakar Naidu\nhosted by Robert Seiringer\nAbstract: I will talk about the momentum distribution of an interacting Fermi gas on a three dimensional torus in mean field regime in a trial state that repro duces the Gell-Mann-Brueckner prediction for the correlation energy for Co ulomb potential. We show that the momentum distribution is a step function corrected by the random phase approximation as predicted by Bohm-Pines fo r a class of potentials including the Coulomb potential. The key tool for deriving the distribution is a rigorous bosonization method. The expressio n for the momentum distribution contains the contributions of collective e xcitations above the Fermi-surface going beyond the precision of Hartree-F ock theory. This improves the result by Benedikter-Lill by being valid a l arger class of potentials and for momenta closer to the Fermi surface.  LOCATION:Office Bldg West / Ground floor / Heinzel Seminar Room (I21.EG.101 )\, ISTA ORGANIZER:boosthui@ist.ac.at SUMMARY:Diwakar Naidu: Momentum distribution of a Fermi gas with Coulomb in teraction in Random Phase approximation URL:https://talks-calendar.ista.ac.at/events/6289 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010034Z UID:68de4989513e0953257350@ist.ac.at DTSTART:20260318T123000 DTEND:20260318T141500 DESCRIPTION:Speaker: Guanchen Peng\nhosted by Onur Hosten\nAbstract: Altern ating the propagation direction of the Raman light (k-reversal) has been e ssential for implementing traditional large momentum transfer (LMT) for a Raman atom interferometer\, where a series of light pulses are used to per form both /2-pulse and -pulse. In this talk\, I will present our method of performing LMT without k-reversal [1]. We use microwave /2-pulse and Rama n -pulse to perform LMT\, which uses the same principle as shown in the or iginal Spin-Dependent-Kick interferometer [2]. However\, we applied an add itional microwave pulse in the middle of the interferometer sequence to r everse the spin states\, which allows closing of the interferometer arms b y the same Raman light -pulses without k-reversal. I will present a proof- of-principle demonstration of a 4hk atom interferometer and discuss its sc alability to 4Nhk. I will discuss the complicated feature due to the non-u nity fidelity of Raman pulses. I will also comment on the connection betwe en our scheme and the Bragg atom optics. [1] G. Peng \, B. Lanigan \, R. S hah \, J. Lim \, A. Kaushik \, J. P. Cotter \, E. A. Hinds \, and B. E. Sa uer\, Large momentum transfer Raman atom interferometer without k-reversal \, Phys. Rev. Res. 7\, L032045 (2025) [2] M. Jaffe\, V. Xu\, P. Haslinger\ , H. Mller\, and P. Hamilton\, Efficient adiabatic spin-dependent kicks in an atom interferometer\, Phys. Rev. Lett. 121\, 040402 (2018). LOCATION:Moonstone Bldg / Ground floor / Seminar Room G (I24.EG.030g)\, IST A ORGANIZER:swiddman@ist.ac.at SUMMARY:Guanchen Peng: Large momentum transfer Raman atom interferometer wi thout k-reversal AND Common Scientific Meeting URL:https://talks-calendar.ista.ac.at/events/6218 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010034Z UID:68776e696ce62156687372@ist.ac.at DTSTART:20260319T110000 DTEND:20260319T120000 DESCRIPTION:Speaker: Thomas Salez\nhosted by Jérémie Palacci\nAbstract: C olloidal motions near complex boundaries are ubiquitous in fundamental phy sics and biology\, as well as in industrial applications. This class of pr oblems invariably involves the intricate coupling between confined fluid f lows\, soft boundaries\, charges\, external forces and fluctuations. Using a combination of interferometric microscopy and advanced statistical infe rence\, we address such a coupling in two main situations. First\, we cons ider the Brownian motion of a rigid particle near a rigid wall. All the ke y statistical-physics observables are reconstructed with high precision\, allowing for nanoscale resolution of local mobilities and femtonewton infe rence of conservative and nonconservative forces. Furthermore\, we charact erize the displacement non-Gaussianities induced by the flow boundary cond ition at the wall\, and their drastic consequences on target-finding dynam ics. Then\, we investigate the Brownian motion of soft micrometric oil dro plets near rigid walls. The analysis reveals the existence of a novel\, tr ansient but large\, soft-Brownian force. The latter might be of importance for microbiological and nanophysical transport\, as well as for chemical reactions in crowded environments and hence the whole life machinery. LOCATION:Office Bldg West / Ground floor / Heinzel Seminar Room (I21.EG.101 )\, ISTA ORGANIZER:cpetz@ist.ac.at SUMMARY:Thomas Salez: Brownian motion near complex interfaces URL:https://talks-calendar.ista.ac.at/events/6356 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010034Z UID:665dbdca8ef85833342691@ist.ac.at DTSTART:20260319T131500 DTEND:20260319T150000 DESCRIPTION:Speaker: Quan Situ\nhosted by Xujia Chen & Tamás Hausel\nAbstr act: The center of a category is an important invariant. In 1990 Soergel s tudied the center of each block of BGG category O\, and established an alg ebra isomorphism to the singular cohomology ring of certain (partial) flag variety. In this talk\, we will consider an analogue of BGG category O fo r quantum groups at roots of unity\, which involves the so called hybrid ( or mixed) quantum group. We show that the center of each block is isomorph ic to the singular cohomology ring of certain (partial) affine flag variet y. The first half of this talk will be devoted to review Soergels result. In the second half\, we will introduce the quantum category O and discuss our result on its center. LOCATION:Office Bldg West / Ground floor / Heinzel Seminar Room (I21.EG.101 )\, ISTA ORGANIZER:boosthui@ist.ac.at SUMMARY:Quan Situ: Center of quantum category O and cohomology of affine fl ag varieties URL:https://talks-calendar.ista.ac.at/events/6329 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010034Z UID:69941a4daa95e421953637@ist.ac.at DTSTART:20260323T110000 DTEND:20260323T120000 DESCRIPTION:Speaker: Aaradhya Pandey\nhosted by Marco Mondelli\nAbstract: I n this talk\, I introduce a hypothesis-testing-based formulation of differ ential privacy in classical computation. The Gaussian Differential Privacy framework of Dong--Roth--Su (2022) established a central limit theorem fo r the composition of multiple private mechanisms. Building on this work\, I present a Poisson extension of their result and show that both the Gauss ian and Poisson limits are unified under a broader framework of infinitely divisible privacy. This perspective reveals structural connections betwee n differential privacy\, probability theory\, statistics\, and discrete ma thematics. I conclude by discussing computational differential privacy and its connections to cryptographic constructions such as pseudorandom gener ators\, as well as a step toward quantizing privacy in quantum computation \, outlining a framework for both computational and quantum differential p rivacy. LOCATION:Office Bldg West / Ground floor / Heinzel Seminar Room (I21.EG.101 )\, ISTA ORGANIZER:jdeanton@ist.ac.at SUMMARY:Aaradhya Pandey: Information\, Computation\, &\; Quantization: I nfinitely divisible privacy and beyond URL:https://talks-calendar.ista.ac.at/events/6299 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010034Z UID:6687bf08e3e68685081225@ist.ac.at DTSTART:20260324T161500 DTEND:20260324T171500 DESCRIPTION:Speaker: Michiel De Wilde\nhosted by Robert Seiringer\nAbstract : Allow an ideal Bose gas to have any boundary condition. What kind of con densates are possible in the thermodynamic limit? We show that a suitable sequence of boundary conditions for the Laplacian features the appearance of an arbitrary number of condensates\, described by arbitrary harmonic fu nctions. LOCATION:Office Bldg West / Ground floor / Heinzel Seminar Room (I21.EG.101 )\, ISTA ORGANIZER:boosthui@ist.ac.at SUMMARY:Michiel De Wilde: Arbitrary harmonic functions as Bose-Einstein con densates URL:https://talks-calendar.ista.ac.at/events/6359 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010034Z UID:69a9b2967650f821985802@ist.ac.at DTSTART:20260326T113000 DTEND:20260326T123000 DESCRIPTION:Speaker: Bardiya Aryanfard\nAbstract: In the continual observat ion model of differential privacy\, problems are generally considered easy if they admit an additive error polylogarithmic in the stream length T an d the universe size n. Conversely\, problems that require additive error p olynomial in n and T are considered difficult. Recently\, Raskhodikova and Steiner (PODS 25) proved polynomial lower bounds on the additive error of many graph problems under fully dynamic edge differential privacy. This r aises a natural question: are these problems difficult even in the inserti ons-only model\, or does their hardness arise strictly from the fully dyna mic setting?We show that for many problems\, the former is true. We prove polynomial lower bounds for a variety of these problems (e.g.\, maximum ma tching) in the insertions-only setting. We then extend our techniques to t he problem of estimating all symmetric norms simultaneously (SNE)\, provid ing the first polynomial lower bound for this problem.Based on joint work with Monika Henzinger\, David Saulpic\, and A. R. Sricharan (https://arxiv .org/abs/2512.15981\, to appear in PODS 26) LOCATION:Moonstone Bldg / Ground floor / Seminar Room C (I24.EG.030c)\, IST A ORGANIZER:achaturv@ist.ac.at SUMMARY:Bardiya Aryanfard: TCS Seminar - Improved Lower Bounds for Privacy under Continual Release URL:https://talks-calendar.ista.ac.at/events/6369 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010034Z UID:665dbdca90071525382795@ist.ac.at DTSTART:20260326T131500 DTEND:20260326T150000 DESCRIPTION:Speaker: Volodymyr Mazorchuk\nhosted by Tamas Hausel\nAbstract: In the first half  of the talk\, I will give a general introduction to t he so-called Kostant's problem for Lie algebra modules\, as formulated by Joseph in 1980.In the second half\, I will discuss a few recent results on this problem for  simple  highest weight modules and related properties of Kazhdan-Lusztig combinatorics. LOCATION:Office Bldg West / Ground floor / Heinzel Seminar Room (I21.EG.101 )\, ISTA ORGANIZER:boosthui@ist.ac.at SUMMARY:Volodymyr Mazorchuk: Kostant's problem for highest weight modules URL:https://talks-calendar.ista.ac.at/events/6259 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010034Z UID:69c13bfcda1b2375724544@ist.ac.at DTSTART:20260401T140000 DTEND:20260401T150000 DESCRIPTION:Speaker: Vishwesha Guttal\nhosted by Vasudha Kulkarni\, Sylvia Cremer\nAbstract: Biological systems are fundamentally shaped by stochasti city. In my talk\, I will demonstrate the key role of intrinsic noise\, wh ich are fluctuations arising from inherent probabilistic nature of biologi cal interactions and are amplified in finite systems. First\, I will demon strate\, using both theory and empirical data\, how noise can shape order in small to intermediate-sized fish schools. Next\, I will show how noise can inform us about the underlying ecological dynamics. Finally\, I will s how theoretically how the stochasticity of finite populations can exhibit counter-intuitive dynamics on both ecological and evolutionary time scales . LOCATION:Mondi Seminar Room 3\, Central Building\, ISTA ORGANIZER:vkulkarn@ist.ac.at SUMMARY:Vishwesha Guttal: The role of intrinsic noise in biological systems : from animal groups to populations to evolution URL:https://talks-calendar.ista.ac.at/events/6372 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010034Z UID:698aeafda7e08601921534@ist.ac.at DTSTART:20260401T150000 DTEND:20260401T163000 DESCRIPTION:Speaker: David Taylor\nhosted by Prof. Jack Bravo\nAbstract: CR ISPRCas9s clinical utility is constrained by strict PAM requirements and t he inability to package large nucleases into AAV vectors. We engineered a modular Cas9\, split into a nuclease scaffold and an exchangeable PAM-inte racting domain (PID). This architecture enables one scaffold to function w ith multiple PIDs\, allowing ultra-multiplexing and simple PID swapping to target all disease-relevant loci. Guided by cryo-EM\, we identified funct ional split sites\, validated activity with a GFP reporter assay\, and res tored fast cleavage kinetics using intein-mediated ligation. Exchanging PI Ds broadened PAM compatibility significantly\, with several split chimeras achieving robust editing across any site in human cells. This precision n uclease system offers a compact\, PAM-flexible platform that fits within a single AAV and establishes a path toward versatile\, clinical genome-edit ing therapies. LOCATION:Central Bldg / O1 / Mondi 2a (I01.O1.008)\, ISTA ORGANIZER:jbravo@ist.ac.at SUMMARY:David Taylor: "\;Reengineering CRISPR-Cas effectors"\; URL:https://talks-calendar.ista.ac.at/events/6321 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010034Z UID:69c0fcd2533c8436387966@ist.ac.at DTSTART:20260403T110000 DTEND:20260403T120000 DESCRIPTION:Speaker: Christian Santangelo\nhosted by Scott Waitukaitis\nAbs tract: The materials of biology\, from sharkskin to cartilage to wood\, re gularly out-perform their synthetic equivalents. Organisms can achieve thi s because their materials have precise geometric structures that endow the m with tailored mechanical properties that can often be changed in situ. I t has recently become possible to fabricate comparable structures through 3D printing\, but we still seem to understand little about how geometry an d mechanics are intertwined. This talk will discuss why this is a hard pro blem (NP-hard actually)\, and highlight new work by my group and collabora tors that are starting to unveil new connections between geometry and mech anics. This new understanding has allowed us to design materials that can change their mechanical properties\, changing from rigid to floppy due to the imposition of internal stresses\, and sheds light on the flexibility o f shells and other structures. LOCATION:Moonstone Bldg / Ground floor / Seminar Room F (I24.EG.030f)\, IST A ORGANIZER:cpetz@ist.ac.at SUMMARY:Christian Santangelo: How geometry and topology make materials rigi d or floppy URL:https://talks-calendar.ista.ac.at/events/6375 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010034Z UID:68776fd7287fd077847583@ist.ac.at DTSTART:20260409T110000 DTEND:20260409T120000 DESCRIPTION:Speaker: Martin van Hecke\nhosted by Scott Waitukaitis\nAbstrac t: Memory effects probe the complexity of disordered matter and its fundam ental constituents and interactions. While models based on independent ele ments capture generic memories\, interactions are predicted to produce man y interaction-induced memories which so far have been observed in artifici al systems only. Here we reveal that archetypical disordered materials - p olycrystalline alloys\, crumpled sheets\, and steel wool - store multiple memories that strengthen with repeated cycling - in stark contrast to pred ictions for non-interacting systems. Interacting-based models capture our observations and predict a cascade of interaction-induced memory motifs\, including the dominant one observed here. Our results reveal hitherto hidd en complexity in disordered media\, opening a fresh route towards the obse rvation\, modeling and utilization of interaction-induced memories\, inclu ding for in-materia computing. LOCATION:Mondi Seminar Room 2\, Central Building\, ISTA ORGANIZER:cpetz@ist.ac.at SUMMARY:Martin van Hecke: Interaction-Induced Memories Reveal the Complexit y of Disordered Matter URL:https://talks-calendar.ista.ac.at/events/6380 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010034Z UID:69b2997d0b482398218529@ist.ac.at DTSTART:20260409T113000 DTEND:20260409T123000 DESCRIPTION:Speaker: Frederik Mallmann-Trenn\nAbstract: The strong lottery ticket hypothesis (SLTH) posits that\, for any given target network\, a su fficiently large randomly initialized neural network contains a subnetwork whose inputoutput behavior can approximate that target. This viewpoint su ggests an alternative paradigm for model design: rather than adjusting par ameters through training\, we can search for effective subnetworks by prun ing. In this talk\, I will introduce the SLTH and discuss several pruning approaches. LOCATION:Sunstone Bldg / Ground floor / Big Seminar Room A / 27 seats (I23. EG.102)\, ISTA ORGANIZER:achaturv@ist.ac.at SUMMARY:Frederik Mallmann-Trenn: TCS Seminar - On the Strong Lottery Ticket Hypothesis URL:https://talks-calendar.ista.ac.at/events/6397 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010034Z UID:665dbdca92263894233087@ist.ac.at DTSTART:20260409T133000 DTEND:20260409T150000 DESCRIPTION:Speaker: Jochen Heinloth\nhosted by Xujia Chen & Tamas Hausel\n Abstract: The talk will be an extension of a preparational talk in the Fri day-Bourbaki seminar\, with only aim to give some background on the geomet ric Langlands correspondence.The question started out with an arithmetic q uestion and part of the recent progress has relied on a very fruitful exch ange of ideas between arithmetic and geometric perspectives\, that finally allowed Gaitsgory and Raskin to deduce results for the original correspon dence in the case of function fields from an abstract looking categorical result. It is quite beautiful that the abstract looking statement can be u sed to deduce a classical statement on automorphic functions.The different settings involved mean that if you either like arithmetic questions or co mplex geometry you might appreciate some aspects of this and I will try to explain some of the more elementary ideas that serve as starting point to translate between these languages. LOCATION:Raiffeisen Lecture Hall\, Central Building\, ISTA ORGANIZER:boosthui@ist.ac.at SUMMARY:Jochen Heinloth: Some background on the geometric Langlands corresp ondence URL:https://talks-calendar.ista.ac.at/events/6272 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010034Z UID:699c104cded21642660514@ist.ac.at DTSTART:20260415T110000 DTEND:20260415T120000 DESCRIPTION:Speaker: Filippo Conforto\nhosted by Andela Saric\nAbstract: Th e activity and organisation of DNA in the cell are highly regulated by sev eral proteins\, such as topoisomerases and Structural Maintenance of Chrom osomes (SMCs)\, which are involved in topological regulation by resolving crossings between DNA strands or creating loops within chromatin. While we have rich knowledge about the impact of these proteins on the cell's func tion\, the rheological\, i.e.\, flow properties\, which affect the capacit y of DNA to reorganise and respond to stimuli\, are still poorly understoo d.In this talk\, I will investigate the viscous and elastic properties of dense DNA solutions under the effect of SMCs and the formation of gels thr ough DNA ligation. Specifically\, I show how SMCs modulate in silico and i n vitro the rheological properties both through the extrusion of loops and the creation of transient crosslinks between DNA strands. Additionally\, I investigate how DNA can be used to create percolating networks of linked rings. These DNA networks\, called "Olympic Gels''\, differ from classic transiently linked gels by the presence of permanent topological links. I show that through progressive ligation it is possible to create materials with tuneable viscoelastic properties\, which can be controlled by choosin g the length of ring and linear DNA strands used in the gel formation. Thi s work contributes to a better understanding of how proteins naturally con tained in the cell affect the topology\, structure\, and rheology of entan gled DNA\, and will help guide the design of new biomaterials inspired by the properties of DNA. LOCATION:Sunstone Bldg / Ground floor / Big Seminar Room A / 27 seats (I23. EG.102)\, ISTA ORGANIZER:mmunozba@ist.ac.at SUMMARY:Filippo Conforto: Modulating the flow of entangled DNA with topolog ically active proteins URL:https://talks-calendar.ista.ac.at/events/6381 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010034Z UID:1776338100@ist.ac.at DTSTART:20260416T131500 DTEND:20260416T150000 DESCRIPTION:Speaker: Isabella Khan\nhosted by Xujia Chen\nAbstract: The Hee gaard Floer d-invariant is a numerical invariant of rational homology sphe res which is analogous to the Frøyshov h-invariant from Instanton theory. In this talk\, we use Zemke’s recent isomorphism between lattice Floer and Heegaard Floer homology to compute the d-invariant for all rational ho mology spheres which arise as negative definite plumbed manifolds\, verify ing a 20 year old conjecture of Némethi.  LOCATION:Office Bldg West / Ground floor / Heinzel Seminar Room (I21.EG.101 )\, ISTA ORGANIZER:Stephanie.Dolot@ist.ac.at SUMMARY:Isabella Khan: The Heegaard Floer d-invariant for rational homology spheres URL:https://talks-calendar.ista.ac.at/events/6403 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010034Z UID:69d4fd9cf30db116400989@ist.ac.at DTSTART:20260423T110000 DTEND:20260423T120000 DESCRIPTION:Speaker: Beate Lichtenberger\nhosted by Florian Schur\nAbstract : Skin fibroblasts are central organizers of tissue architecture\, providi ng the structural framework of theskin while actively regulating its devel opment\, homeostasis\, and repair. Far from being a uniform cellpopulation \, fibroblasts comprise diverse subtypes with distinct spatial identities\ , functional programs\,and interactions with epithelial\, immune\, and vas cular cells. In this talk\, I will discuss how fibroblastdiversity shapes skin structure and physiology\, and how altered fibroblast states drive pa thologicalprocesses such as fibrosis and cancer. These findings position f ibroblasts as dynamic regulators of tissuefunction in both health and dise ase. LOCATION:Moonstone Bldg / Ground floor / Seminar Room F (I24.EG.030f)\, IST A ORGANIZER:jgazsi@ist.ac.at SUMMARY:Beate Lichtenberger: Beyond Structural Support: Skin Fibroblasts as Dynamic Regulators of Tissue and Disease URL:https://talks-calendar.ista.ac.at/events/6404 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010034Z UID:665dbdca9443e835749719@ist.ac.at DTSTART:20260423T131500 DTEND:20260423T151500 DESCRIPTION:Speaker: David Hernandez\nhosted by Xujia Chen & Tamas Hausel\n Abstract: Shifted quantum groups emerged from the study of quantized Coulo mb branches (which are symplectic duals to quiver varieties). We show that the Grothendieck ring of the category O for the shifted quantum affine al gebras has the structure of a cluster algebra (jt work with Geiss and Lecl erc). This has several applications\, such as geometric character formulas for simple classes corresponding to cluster variables. LOCATION:Office Bldg West / Ground floor / Heinzel Seminar Room (I21.EG.101 )\, ISTA ORGANIZER:boosthui@ist.ac.at SUMMARY:David Hernandez: Shifted quantum groups\, cluster algebras and geom etric character formulas URL:https://talks-calendar.ista.ac.at/events/6363 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010034Z UID:6687bf08e3e87989250506@ist.ac.at DTSTART:20260428T161500 DTEND:20260428T171500 DESCRIPTION:Speaker: Jacob Shapiro\nhosted by Laszlo Erdös\nAbstract: The index of a pair of projections on a Hilbert space was introduced in 1973 b y Brown-Douglas-Filmore and connected to the integer quantum Hall effect b y Avron-Seiler-Simon in 1994. For two orthogonal projections P\,Q such tha t P-Q is compact\, index(P\,Q)=dimimPkerQ-dimimQkerP. It is manifestly an integer\, and enjoys norm and compactness stability\, much like the relate d Fredholm index. Such indices played a pivotal role in describing the qua ntization and stability properties in the quantum Hall effect\; ASS94 rela ted the Hall conductance to the index of a Fermi projection P and its Laug hlin-flux-inserted projection U*PU.What becomes of this story in the prese nce of interactions? To describe infinitely-many interacting electrons in infinite-volume\, the Hilbert space is replaced by a unital C-* algebra A (a CAR algebra)\, but there is no obvious notion of a Fredholm index. We i ntroduce a new notion\, the index of a pair of pure states (on A)\, prove its quantization\, invariance and stability properties\, and relate it to the (possibly fractional) Hall conductance. We further show that Kitaevs i nvertible states always have integer conductance. Joint with Bachmann and Tauber. LOCATION:Office Bldg West / Ground floor / Heinzel Seminar Room (I21.EG.101 )\, ISTA ORGANIZER:boosthui@ist.ac.at SUMMARY:Jacob Shapiro: The index of a pair of pure states and the quantum H all effect URL:https://talks-calendar.ista.ac.at/events/6368 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010034Z UID:68776eaf380dd057014767@ist.ac.at DTSTART:20260430T110000 DTEND:20260430T120000 DESCRIPTION:Speaker: Justin C. Burton\nhosted by Scott Waitukaitis\nAbstrac t: Airborne microbes critically impact our lives\, from the spread of dise ases to rainfall and food production. Yet the survival of microbes during aerosolization and atmospheric transport is not well understood. Although bacteria have been found in the atmosphere\, even larger organisms such as nematodes and spiders can drift in the air for many kilometers. In this t alk\, I will discuss two research projects where we investigate how the at mosphere plays a crucial role in micro- and meso-scale ecology. I will sho w how salt and humidity help bacteria survive during desiccation. In dried droplets on flat surfaces\, the spatial structure generated by the dried film can trap water to facilitate survival. 3D Bacterial suspensions dried under acoustic levitation survive even better. In a separate project\, I will discuss how jumping\, parasitic nematodes rely on electrostatic force s to infect their insect hosts. A model combining electrostatics\, aerodyn amics\, and Bayesian inference indicates that the electrostatic charge on jumping nematodes is ~ 0.1 pC\, which aligns with theoretical predictions for electrostatic induction. In fact\, we show that infection through jump ing may necessitate electrostatic forces as a successful evolutionary stra tegy. LOCATION:Office Bldg West / Ground floor / Heinzel Seminar Room (I21.EG.101 )\, ISTA ORGANIZER:cpetz@ist.ac.at SUMMARY:Justin C. Burton: Biology in the air: from hitchhiking microbes to jumping electrified nematodes URL:https://talks-calendar.ista.ac.at/events/6407 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010034Z UID:68776f9104d40763009008@ist.ac.at DTSTART:20260507T110000 DTEND:20260507T120000 DESCRIPTION:Speaker: Nachi Stern\nhosted by Carl Goodrich\nAbstract: From e lectrically responsive neuronal networks to immune repertoires\, biologica l systems can learn to perform complex tasks. In this seminar\, we explore physical learning\, a framework inspired by computational learning theory and biological systems\, where networks physically adapt to applied force s to adopt desired functions. Unlike traditional engineering approaches or artificial intelligence\, physical learning is facilitated by physically realizable learning rules\, requiring only local responses and no explicit information about the desired functionality. Our research shows that such local learning rules can be derived for broad classes of physical network s and that physical learning is indeed physically realizable\, without com puter aid\, through laboratory experiments. We take further inspiration fr om learning in the brain and demonstrate the success of physical learning beyond the quasi-equilibrium regime\, enabling physical systems to adapt c omplex dynamical functions. By leveraging the advances of statistical lear ning theory in physical machines\, we propose physical learning as a promi sing bridge between computational machine learning and biology\, with the potential to enable the development of power-efficient AI platforms\, and new classes of smart metamaterials that adapt in-situ to users needs. LOCATION:Mondi Seminar Room 2\, Central Building\, ISTA ORGANIZER:cpetz@ist.ac.at SUMMARY:Nachi Stern: Learning without neurons in physical systems URL:https://talks-calendar.ista.ac.at/events/6287 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010034Z UID:69c104cda01c7847075710@ist.ac.at DTSTART:20260512T140000 DTEND:20260512T150000 DESCRIPTION:Speaker: Sashi Weerawarana\nhosted by Florian Schur\nAbstract: All living beings must package and compact their DNA to protect genetic ma terial and regulate genome access. In my thesis work\, I investigate genom e organization in mitochondria\, bacteria\, and viruses. Mitochondria util ize the HMG-box protein TFAM to fulfill this vital role\, whereas bacteria and viruses employ histone proteins that adopt different binding modes. T he central focus of this talk is TFAM-mediated DNA compaction. Using a wid e array of biochemical methods and structural biology approaches\, I show that TFAM compacts DNA into homogenous higher-order complexes that exhibit continuous conformational dynamics. The talk also presents cryo EM data r evealing distinct strategies utilized by bacterial histones from Bdellovib rio bacteriovorus and Leptospira interrogans to compact DNA and highlights unique structural features of the Medusavirus medusae nucleosome. Togethe r\, this work reveals diverse mechanisms of genome compaction across organ elles and domains of life. LOCATION:Mondi Seminar Room 2\, Central Building\, ISTA ORGANIZER:jgazsi@ist.ac.at SUMMARY:Sashi Weerawarana: Genome organization in mitochondria\, bacteria\, and viruses URL:https://talks-calendar.ista.ac.at/events/6371 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010034Z UID:1779786000@ist.ac.at DTSTART:20260526T110000 DTEND:20260526T120000 DESCRIPTION:Speaker: Jie Ren\nhosted by Maksym Serbyn\nAbstract: Abstract: Understanding how complex systems transition between order and chaos is a central challenge of nonequilibrium physics. While weak perturbations of c lassical integrable systems give rise to a mixed phase space of coexisting regular and chaotic trajectories\, analogous behavior in interacting quan tum many-body systems has remained elusive. Here we develop and experiment ally implement a hybrid quantum–classical feedback protocol that autonom ously discovers and stabilizes long-lived regular trajectories in a superc onducting quantum processor. Each iteration combines short-time quantum ev olution with classical optimization that projects the dynamics back onto a low-entanglement variational manifold\, effectively distilling coherence from chaotic evolution. The stabilized trajectories reveal a quantum many- body mixed phase space emerging from nonlinear variational dynamics\, with out a direct analogue in classical or few-body quantum systems. Our result s establish a versatile framework for algorithmic discovery and control of coherent dynamics previously inaccessible to experiment.  LOCATION:Office Bldg West / Ground floor / Heinzel Seminar Room (I21.EG.101 )\, ISTA ORGANIZER:Stephanie.Dolot@ist.ac.at SUMMARY:Jie Ren: “Quantum many-body mixed phase space revealed by hybrid feedback control" URL:https://talks-calendar.ista.ac.at/events/6345 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010034Z UID:1779958800@ist.ac.at DTSTART:20260528T110000 DTEND:20260528T120000 DESCRIPTION:Speaker: Federica Surace\nhosted by Maksym Serbyn\nAbstract: TB A LOCATION:Central Bldg / O1 / Mondi 2a\, ISTA ORGANIZER:Stephanie.Dolot@ist.ac.at SUMMARY:Federica Surace: "Slow dynamics in quantum many-body systems" URL:https://talks-calendar.ista.ac.at/events/6217 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010034Z UID:68776ee57aa4b682558249@ist.ac.at DTSTART:20260528T110000 DTEND:20260528T120000 DESCRIPTION:Speaker: Mitja Drab\nhosted by Andela Saric\nAbstract: Biologic al membranes are active\, multicomponent systems whose shape emerges from a complex interplay between curvature-inducing inclusions\, in-plane order ing\, and cytoskeletal forces. In this talk\, I present a numerical framew ork for modeling closed membranes populated by curved anisotropic componen ts that interact via nematic alignment and couple to active forces. Our si mulations reveal a rich landscape of membrane morphologies arising from th e competition between intrinsic curvature\, nematic interactions\, and act ive stresses. We show how nematic alignment organizes curved inclusions in to defect structures that localize in regions of high curvature\, thereby guiding membrane remodeling and stabilizing complex shapes such as tubules \, necks\, and pearled structures . Active forces further drive the system out of equilibrium\, enabling transitions to morphologies that are inacce ssible in passive systems\, including flattened\, protrusive\, and dynamic ally fluctuating states. These results provide a unified physical picture of how curvature\, orientational order\, and active forces cooperate to co ntrol membrane shape\, with implications for processes ranging from endocy tosis and phagocytosis to cell spreading and motility. LOCATION:Office Bldg West / Ground floor / Heinzel Seminar Room (I21.EG.101 )\, ISTA ORGANIZER:cpetz@ist.ac.at SUMMARY:Mitja Drab: Numerical Modeling of Nematic Membranes with Active Cur ved Anisotropic Inclusions URL:https://talks-calendar.ista.ac.at/events/6382 END:VEVENT BEGIN:VEVENT DTSTAMP:20260416T010034Z UID:665dbdca9d01d401146589@ist.ac.at DTSTART:20260618T130000 DTEND:20260618T150000 DESCRIPTION:Speaker: Jianrong Li\nhosted by Tamas Hausel\nAbstract: Frenkel and Reshetikhin introduced q-characters for finite-dimensional representa tions of quantum affine algebras\, providing a fundamental tool in their r epresentation theory. Together with Tomasz Przezdziecki\, we defined bound ary q-characters for finite dimensional representations of quantum affine symmetric pairs of split and quasi-split types. In this talk\, I will pres ent a new joint work Tomasz Przezdziecki on evaluation modules for split q uantum affine symmetric pairs. By computing the action of generators in Lu and Wangs Drinfeld-type presentation on GelfandTsetlin bases\, we determi ne the spectrum of a large commutative subalgebra arising from this presen tation. This leads to an explicit formula for boundary analogues of q-char acters\, which we interpret combinatorially in terms of semistandard Young tableaux. Our results show that boundary q-characters share familiar feat ures with ordinary q-characters\, while also exhibiting new phenomena\, in cluding an additional symmetry. LOCATION:Office Bldg West / Ground floor / Heinzel Seminar Room (I21.EG.101 )\, ISTA ORGANIZER:boosthui@ist.ac.at SUMMARY:Jianrong Li: Boundary q-characters of finite-dimensional representa tions of quantum affine symmetric pairs URL:https://talks-calendar.ista.ac.at/events/6284 END:VEVENT END:VCALENDAR