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Publication Kathryn Schwartz, Book Historian of the Modern Middle East(Cambridge University Press, 2025-03-13) Blair, Ann; Zeghal, MalikaThis article presents the contributions of Dr. Kathryn Schwartz (1984-2022), book historian of the modern Middle East. Her study of the origins and impact of the printing press in late Ottoman Egypt has challenged some long-standing assumptions in the historiography. She has also put into question the long-held belief that Ottomans banned printing. More broadly, her work has challenged Eurocentric approaches to this topic and has innovated by combining material and intellectual history.Publication Active and stable PtPd diesel oxidation catalysts under industry-defined test protocols(ChemSusChem, 2025-02-28) Lim, Kang Rui Garrick; Lim, Kang Rui Garrick; Shirman, Tanya; Toops, Todd J.; Alvarenga, Jack; Aizenberg, Michael; Aizenberg, JoannaNanoparticle-supported Pt and Pd catalysts are employed industrially to convert CO and hydrocarbon residue from incomplete diesel fuel combustion. However, these catalysts deactivate over time due to sintering, especially for Pt nanoparticles which readily generate volatile species under high operating temperatures. Here, we turned the detrimental vapor-mediated sintering of Pt into an advantage by using a physical mixture of Pt and Pd catalysts prepared using a raspberry-colloid-templating (RCT) method. The RCT method produced Pt/Al2O3 and Pd/Al2O3 catalysts with partially embedded NPs to inhibit surface-mediated sintering pathways. As validated using an industry-defined emission control test protocol, aging a physical mixture of Pt/Al2O3 and Pd/Al2O3 at high temperature produced an alloyed PtPd/Al2O3 catalyst that outperformed the fresh catalyst mixture and both individual catalysts for hydrocarbon conversion, while exhibiting high catalytic stability and resistance to sintering and to SO2 poisoning. X-ray photoelectron spectroscopy revealed that in the aged catalyst mixture, half of the Pd content existed in their more active metallic state, compared to the less active oxide forms in the fresh mixture and both individual catalysts, explaining the unusual activity enhancement. Our results represent a practical approach to producing active and stable PtPd/Al2O3 diesel oxidation catalysts for emission control applications.Publication Investment Feminism and Women's Health(2024) DiMarco, Marina; Higgins, Abigail; Richardson, Sarah; Bruch, Joseph Dov; Marsella, JamieThis essay introduces the term investment feminism to characterize the phenomenon in which financial actors position investment as a powerful lever for advancing gender equity. We offer investment feminism as an analytic tool that illuminates patterns and relations incompletely revealed by existing concepts such as commodity feminism and neoliberal feminism. We develop the concept of investment feminism through a close analysis of its role in the femtech industry, which markets technology and products to promote women's health. Drawing on industry reports, press coverage, and marketing materials, we describe how venture capital firms and femtech startups proffer financial investment as a high-impact means of feminist political action. We argue that while technology has the potential to yield services, tools, diagnostics, and therapies that benefit women, the technological solutions promoted by investment feminism within the women’s health space favor individual self-maintenance rather than structural change. We offer the concept of investment feminism as an analytic tool to support feminist scholars and activists in attending to the role of the financial sector and its ever-increasing influence on gender relations and feminist movements.Publication On the Computational Power of QAC0 with Barely Superlinear Ancillae(2024-10-09) Anshu, Anurag; Dong, Yangjing; Ou, Fenging; Yao, PenghuiQAC0 is the family of constant-depth polynomial-size quantum circuits consisting of arbitrary single qubit unitaries and multi-qubit Toffoli gates. It was introduced by Moore [arXiv: 9903046] as a quantum counterpart of AC0, along with the conjecture that QAC0 circuits can not compute PARITY. In this work we make progress on this longstanding conjecture: we show that any depth-d QAC0 circuit requires n1+3−d ancillae to compute a function with approximate degree Θ(n), which includes PARITY, MAJORITY and MODk. We further establish superlinear lower bounds on quantum state synthesis and quantum channel synthesis. This is the first superlinear lower bound on the super-linear sized QAC0. Regarding PARITY, we show that any further improvement on the size of ancillae to n1+exp(−o(d)) would imply that PARITY ∉ QAC0. These lower bounds are derived by giving low-degree approximations to QAC0 circuits. We show that a depth-d QAC0 circuit with a ancillae, when applied to low-degree operators, has a degree (n+a)1−3−d polynomial approximation in the spectral norm. This implies that the class QLC0, corresponding to linear size QAC0 circuits, has approximate degree o(n). This is a quantum generalization of the result that LC0 circuits have approximate degree o(n) by Bun, Robin, and Thaler [SODA 2019]. Our result also implies that QLC0≠NC1.Publication UniqueQMA vs QMA: oracle separation and eigenstate thermalization hypothesis(2024-10-31) Anshu, Anurag; Haferkamp, Jonas; Hwang, Yeongwoo; Nguyen, Quynh T.We study the long-standing open question of the power of unique witness in quantum protocols, which asks if UniqueQMA, a variant of QMA whose accepting witness space is 1-dimensional, is equal to QMA. We show a quantum oracle separation between UniqueQMA and QMA via an extension of the Aaronson-Kuperberg's QCMA vs QMA oracle separation. In particular, we show that any UniqueQMA protocol must make Ω(D−−√) queries to a subspace phase oracle of unknown dimension ≤D to "find" the subspace. This presents an obstacle to relativizing techniques in resolving this question (unlike its classical analogue - the Valiant-Vazirani theorem - which is essentially a black-box reduction) and suggests the need to study the structure of the ground space of local Hamiltonians in distilling a potential unique witness. Our techniques also yield a quantum oracle separation between QXC, the class characterizing quantum approximate counting, and QMA. Very few structural properties are known that place the complexity of local Hamiltonians in UniqueQMA. We expand this set of properties by showing that the ground energy of local Hamiltonians that satisfy the eigenstate thermalization hypothesis (ETH) can be estimated through a UniqueQMA protocol. Specifically, our protocol can be viewed as a quantum expander test in a low energy subspace of the Hamiltonian and verifies a unique entangled state in two copies of the subspace. This allows us to conclude that if UniqueQMA ≠ QMA, then QMA-hard Hamiltonians must violate ETH under adversarial perturbations (more accurately, under the quantum PCP conjecture if ETH only applies to extensive energy subspaces). Our results serve as evidence that chaotic local Hamiltonians, such as the SYK model, contain polynomial verifiable quantum states in their low energy regime and may be simpler than general local Hamiltonians if UniqueQMA ≠ QMA.Publication Learning Shallow Quantum Circuits(Association for Computing Machinery, 2024-06-11) Huang, Hsin-Yuan; Anshu, Anurag; Liu, Yunchao; Broughton, Michael; Kim, Isaac; Landau, Zeph; McClean, Jarrod R.Despite fundamental interests in learning quantum circuits, the existence of a computationally efficient algorithm for learning shallow quantum circuits remains an open question. Because shallow quantum circuits can generate distributions that are classically hard to sample from, existing learning algorithms do not apply. In this work, we present a polynomial-time classical algorithm for learning the description of any unknown n-qubit shallow quantum circuit U (with arbitrary unknown architecture) within a small diamond distance using single-qubit measurement data on the output states of U. We also provide a polynomial-time classical algorithm for learning the description of any unknown n-qubit state | ψ ⟩ = U | 0n ⟩ prepared by a shallow quantum circuit U (on a 2D lattice) within a small trace distance using single-qubit measurements on copies of | ψ ⟩. Our approach uses a quantum circuit representation based on local inversions and a technique to combine these inversions. This circuit representation yields an optimization landscape that can be efficiently navigated and enables efficient learning of quantum circuits that are classically hard to simulate.Publication Identification of more than 40 gravitationally magnified stars in a galaxy at redshift 0.725(Springer Science and Business Media LLC, 2025-01-06) Fudamoto, Yoshinobu; Sun, Fengwu; Diego, Jose M.; Dai, Liang; Oguri, Masamune; Zitrin, Adi; Zackrisson, Erik; Jauzac, Mathilde; Lagattuta, David J.; Egami, Eiichi; Iani, Edoardo; Windhorst, Rogier A.; Abe, Katsuya T.; Bauer, Franz Erik; Bian, Fuyan; Bhatawdekar, Rachana; Broadhurst, Thomas J.; Cai, Zheng; Chen, Chian-Chou; Chen, Wenlei; Cohen, Seth H.; Conselice, Christopher J.; Espada, Daniel; Foo, Nicholas; Frye, Brenda L.; Fujimoto, Seiji; Furtak, Lukas J.; Golubchik, Miriam; Hsiao, Tiger Yu-Yang; Jolly, Jean-Baptiste; Kawai, Hiroki; Kelly, Patrick L.; Koekemoer, Anton M.; Kohno, Kotaro; Kokorev, Vasily; Li, Mingyu; Li, Zihao; Lin, Xiaojing; Magdis, Georgios E.; Meena, Ashish K.; Niemiec, Anna; Nabizadeh, Armin; Richard, Johan; Steinhardt, Charles L.; Wu, Yunjing; Zhu, Yongda; Zou, Siwei; fudamoto, yoshinobuStrong gravitational magnifications enable to detect faint background sources, resolve their internal structures, and even identify individual stars in distant galaxies. Highly magnified individual stars allow various appli- cations, including studies of stellar populations in dis- tant galaxies and constraining dark matter structures in the lensing plane. However, these applications have been hampered by the small number of individual stars observed, as typically one or a few stars are identified from each distant galaxy. Here, we report the discovery of more than 40 microlensed stars in a single galaxy be- hind Abell 370 at redshift of 0.725 when the Universe was half of its current age (dubbed “the Dragon arc”), using James Webb Space Telescope (JWST) observations with the time-domain technique. These events are found near the expected lensing critical curves, suggesting that these are magnified stars that appear as transients from intr- acluster stellar microlenses. Through multi-wavelength photometry, we constrain stellar types and find that many of them are consistent with red giants/supergiants magnified by factors of hundreds. This finding reveals an unprecedented high occurrence of microlensing events in the Dragon arc, and proves that JWST’s time-domain observations open up the possibility of conducting statistical studies of high-redshift stars.Publication Opportunities in nanoscale probing of laser-driven phase transitions(Springer Science and Business Media LLC, 2024-08-28) Yannai, Michael; Haller, Matan; Ruimy, Ron; Gorlach, Alexey; Rivera, Nicholas; Basov, Dmitri N.; Kaminer, IdoPublication Quantum error correction below the surface code thresholdGoogle Quantum AI; Lee, JoonhoPublication Thermalization and criticality on an analogue–digital quantum simulator(Springer Science and Business Media LLC, 2025-2-5) Andersen, T. I.; Astrakhantsev, N.; Karamlou, A. H.; Berndtsson, J.; Motruk, J.; Szasz, A.; Gross, J. A.; Schuckert, A.; Westerhout, T.; Zhang, Y.; Forati, E.; Rossi, D.; Kobrin, B.; Paolo, A. Di; Klots, A. R.; Drozdov, I.; Kurilovich, V.; Petukhov, A.; Ioffe, L. B.; Elben, A.; Rath, A.; Vitale, V.; Vermersch, B.; Acharya, R.; Beni, L. A.; Anderson, K.; Ansmann, M.; Arute, F.; Arya, K.; Asfaw, A.; Atalaya, J.; Ballard, B.; Bardin, J. C.; Bengtsson, A.; Bilmes, A.; Bortoli, G.; Bourassa, A.; Bovaird, J.; Brill, L.; Broughton, M.; Browne, D. A.; Buchea, B.; Buckley, B. B.; Buell, D. A.; Burger, T.; Burkett, B.; Bushnell, N.; Cabrera, A.; Campero, J.; Chang, H.-S.; Chen, Z.; Chiaro, B.; Claes, J.; Cleland, A. Y.; Cogan, J.; Collins, R.; Conner, P.; Courtney, W.; Crook, A. L.; Das, S.; Debroy, D. M.; Lorenzo, L. De; Barba, A. Del Toro; Demura, S.; Donohoe, P.; Dunsworth, A.; Earle, C.; Eickbusch, A.; Elbag, A. M.; Elzouka, M.; Erickson, C.; Faoro, L.; Fatemi, R.; Ferreira, V. S.; Burgos, L. Flores; Fowler, A. G.; Foxen, B.; Ganjam, S.; Gasca, R.; Giang, W.; Gidney, C.; Gilboa, D.; Giustina, M.; Gosula, R.; Dau, A. Grajales; Graumann, D.; Greene, A.; Habegger, S.; Hamilton, M. C.; Hansen, M.; Harrigan, M. P.; Harrington, S. D.; Heslin, S.; Heu, P.; Hill, G.; Hoffmann, M. R.; Huang, H.-Y.; Huang, T.; Huff, A.; Huggins, W. J.; Isakov, S. V.; Jeffrey, E.; Jiang, Z.; Jones, C.; Jordan, S.; Joshi, C.; Juhas, P.; Kafri, D.; Kang, H.; Kechedzhi, K.; Khaire, T.; Khattar, T.; Khezri, M.; Kieferová, M.; Kim, S.; Kitaev, A.; Klimov, P.; Korotkov, A. N.; Kostritsa, F.; Kreikebaum, J. M.; Landhuis, D.; Langley, B. W.; Laptev, P.; Lau, K.-M.; Guevel, L. Le; Ledford, J.; Lee, J.; Lee, K. W.; Lensky, Y. D.; Lester, B. J.; Li, W. Y.; Lill, A. T.; Liu, W.; Livingston, W. P.; Locharla, A.; Lundahl, D.; Lunt, A.; Madhuk, S.; Maloney, A.; Mandrà, S.; Martin, L. S.; Martin, O.; Martin, S.; Maxfield, C.; McClean, J. R.; McEwen, M.; Meeks, S.; Miao, K. C.; Mieszala, A.; Molina, S.; Montazeri, S.; Morvan, A.; Movassagh, R.; Neill, C.; Nersisyan, A.; Newman, M.; Nguyen, A.; Nguyen, M.; Ni, C.-H.; Niu, M. Y.; Oliver, W. D.; Ottosson, K.; Pizzuto, A.; Potter, R.; Pritchard, O.; Pryadko, L. P.; Quintana, C.; Reagor, M. J.; Rhodes, D. M.; Roberts, G.; Rocque, C.; Rosenberg, E.; Rubin, N. C.; Saei, N.; Sankaragomathi, K.; Satzinger, K. J.; Schurkus, H. F.; Schuster, C.; Shearn, M. J.; Shorter, A.; Shutty, N.; Shvarts, V.; Sivak, V.; Skruzny, J.; Small, S.; Smith, W. Clarke; Springer, S.; Sterling, G.; Suchard, J.; Szalay, M.; Sztein, A.; Thor, D.; Torres, A.; Torunbalci, M. M.; Vaishnav, A.; Vdovichev, S.; Villalonga, B.; Heidweiller, C. Vollgraff; Waltman, S.; Wang, S. X.; White, T.; Wong, K.; Woo, B. W. K.; Xing, C.; Yao, Z. Jamie; Yeh, P.; Ying, B.; Yoo, J.; Yosri, N.; Young, G.; Zalcman, A.; Zhu, N.; Zobrist, N.; Neven, H.; Babbush, R.; Boixo, S.; Hilton, J.; Lucero, E.; Megrant, A.; Kelly, J.; Chen, Y.; Smelyanskiy, V.; Vidal, G.; Roushan, P.; Läuchli, A. M.; Abanin, D. A.; Mi, X.Abstract Understanding how interacting particles approach thermal equilibrium is a major challenge of quantum simulators1,2. Unlocking the full potential of such systems towards this goal requires flexible initial state preparation, precise time evolution and extensive probes for final state characterization. Here we present a quantum simulator comprising 69 superconducting qubits that supports both universal quantum gates and high-fidelity analogue evolution, with performance beyond the reach of classical simulation in cross-entropy benchmarking experiments. This hybrid platform features more versatile measurement capabilities compared with analogue-only simulators, which we leverage here to reveal a coarsening-induced breakdown of Kibble–Zurek scaling predictions3 in the XY model, as well as signatures of the classical Kosterlitz–Thouless phase transition4. Moreover, the digital gates enable precise energy control, allowing us to study the effects of the eigenstate thermalization hypothesis5–7 in targeted parts of the eigenspectrum. We also demonstrate digital preparation of pairwise-entangled dimer states, and image the transport of energy and vorticity during subsequent thermalization in analogue evolution. These results establish the efficacy of superconducting analogue–digital quantum processors for preparing states across many-body spectra and unveiling their thermalization dynamics.