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Since Feynman quantum mechanics is associated with path integrals. However, some aspects of quantum mechanics are best explained using higher dimensional structures, such as strings or branes. I will survey deformation quantization and quantization of integrable systems and their connections to topological strings and four dimensional gauge theories. Our characters will be Heisenberg spin chains, many-body systems, gauge instantons, and quantum hydrodynamics of intermediate long waves. 

Astrophysics and cosmology grew, symbiotically, alongside quantum mechanics, over the past hundred years. The developing fields of atomic, nuclear and particle physics found motivation and application to central problems in astrophysics. These included the elucidation of stellar and interstellar spectra, the powering of stars and supernovae, the origin of the chemical elements, the properties of neutron stars and the interpretation of cosmic rays.  This relationship continues and is expressed in some of the most pressing problems today, notably the nature and consequences of dark matter, the provenance of cosmic structure and baryon asymmetry, the properties of magnetars, the acceleration of the highest energy cosmic rays and the origin of life.

Achieving precise control over microbial community composition is critical for applications ranging from bioremediation to human health but remains challenging due to the complexity of microbial interactions and resource variability. This work presents a framework for the bottom-up engineering of microbial communities by leveraging resource dynamics and temporal niches in fluctuating environments.
This approach assembles and maintains microbial "dream teams" - small, defined communities with desired properties—using serial dilution experiments. By treating resource concentrations as dynamic "control knobs," it enables stable coexistence and precise tuning of species abundances. Theoretical models, informed by experimental data from natural and synthetic microcosms, incorporate ecological and metabolic parameters, including species-specific time lags and dilution factors, to identify resource combinations that maximize community stability and diversity.
I will also describe how to engineer a multi-cycle resource strategy to overcome resource limitations and dramatically increase microbial diversity. By systematically varying resource ratios across growth-dilution cycles, this strategy creates additional temporal niches that allow for the coexistence of a larger number of species than traditional methods. Numerical simulations demonstrate that multi-cycle strategies significantly enhance species diversity, approaching the theoretical upper bound of 2^n-1 species coexisting on n resources.

Starting in the mid-1980s with the quantum control and detection of individual atoms/ions, we now have access to a variety of controllable quantum systems. One particular platform which has emerged as a popular choice is superconducting electrical circuits operating at ultra-low temperatures. These are micro to nanoscale electrical circuits that can be engineered to show quantum mechanical phenomena like superposition and entanglement. In this talk, I will introduce the concept of a quantum electrical circuit and how one can use superconducting materials to build them. The flexibility in circuit design allows one to create near ideal custom Hamiltonians which can be used to implement textbook measurements and explore various phenomena in previously unexplored regimes. The same flexibility also enables the possibility of large-scale chips for quantum computing applications. I will discuss some examples to illustrate the versatility of this platform and also highlight the various challenges in building a practical quantum computer.

On a microscopic scale, our world is governed by quantum physics. Beyond the fundamental questions and 'mysteries' of quantum mechanics, the ability to control this microscopic realm opens up exciting opportunities for new applications and quantum technologies—potentially more powerful than their classical counterparts. As we celebrate 2025 as the International Year of Quantum Science and Technology, marking 100 years since the formulation of quantum mechanics by Heisenberg and Schrödinger, we also commemorate three decades of progress in quantum information and quantum computing. This talk will provide an overview of quantum information from both conceptual and historical perspectives. We will explore the implementation and applications of quantum computers and simulators, quantum networks, and quantum metrology. Our primary focus will be on quantum optical systems, such as atoms and ions manipulated by laser light—prototypical examples of engineered quantum many-body systems. These systems can be controlled at the level of individual quanta, enabling precise manipulation, engineering, and distribution of quantum entanglement. Topics will include trapped ions as universal quantum processors, as well as digital and analog simulations of strongly correlated quantum matter using Rydberg atoms in tweezer arrays. We will highlight current research examples, such as quantum simulations of lattice gauge theories, the characterization and verification of quantum devices through Hamiltonian and Liouvillian learning, and the development of quantum algorithms for optimizing entanglement in quantum sensors.

This talk will go over the history, principles, development, and applications of inelastic light scattering, widely known as the Raman effect, concluding with some remarks on Raman and Mandelstam, the two major figures in the discovery.

Ordered phases of matter have close connections to computation. Two prominent examples are spin glass order, with wide-ranging applications in machine learning and optimization, and topological order, closely related to quantum error correction. Here, we introduce the concept of topological quantum spin glass (TQSG) order which marries these two notions, exhibiting both the complex energy landscapes of spin glasses, and the quantum memory and long-range entanglement characteristic of topologically ordered systems. Our work introduces a topological analog of spin glasses that preserves quantum information and displays robust many-body entanglement even at finite temperatures, opening new avenues for both statistical mechanics and quantum computer science.

Microbial communities assemble and thrive in strongly fluctuating boom-and-bust environments by adopting distinct metabolic strategies to consume resources. While much attention has been given to understanding these strategies in isolated species, their ecological implications in complex communities remain poorly understood. Here, we combine theoretical and computational frameworks to investigate the assembly and ecological properties of microbial communities with diauxic (sequential) and co-utilization strategies.
We show that diauxic microbial communities, where species sequentially utilize resources, spontaneously develop complementary resource preferences during assembly. This complementarity arises because sequential utilization disproportionately relies on the top-choice resource for growth, leading to intuitive ecological partitioning. A geometric approach to analyzing these serially diluted communities further explains emergent patterns, such as the absence of species preferring suboptimal resources for growth.
Comparing sequential and co-utilization strategies, we find that sequential utilizers dominate in species-rich, high-competition communities, leveraging their resilience to fluctuating resource ratios. Their ecological advantage lies in growth rate distributions characterized by wider upper tails, despite lower averages, enabling efficient niche packing and structural stability. Conversely, co-utilizers thrive in low-diversity communities, benefiting from consistently higher average growth rates.
Our work provides a unified explanation for the coexistence of sequential and co-utilizing strategies in natural ecosystems and predicts patterns of community assembly shaped by metabolic strategies. These findings offer testable hypotheses for understanding the dynamics of microbial communities in natural and synthetic environments.