# Quantum simulation costs for Suzuki-Trotter decomposition of quantum many-body lattice models

By: Nathan M. Myers, Ryan Scott, Kwon Park, Vito W. Scarola

Quantum computers offer the potential to efficiently simulate the dynamics of quantum systems, a task whose difficulty scales exponentially with system size on classical devices. To assess the potential for near-term quantum computers to simulate many-body systems we develop a model-independent formalism to straightforwardly compute bounds on the number of Trotter steps needed to accurately simulate the system's time evolution based on the fi... more

# The ANITA Anomalous Events as Signatures of a Beyond Standard Model Particle, and Supporting Observations from IceCube

By: Derek B. Fox, Steinn Sigurdsson, Sarah Shandera, Peter Mészáros, Kohta Murase, Miguel Mostafá, Stephane Coutu (Penn State University)

The ANITA collaboration have reported observation of two anomalous events that appear to be $\varepsilon_{\rm cr} \approx 0.6$ EeV cosmic ray showers emerging from the Earth with exit angles of $27^\circ$ and $35^\circ$, respectively. While EeV-scale upgoing showers have been anticipated as a result of astrophysical tau neutrinos converting to tau leptons during Earth passage, the observed exit angles are much steeper than expected in Stand... more

# Evidence of near-ambient superconductivity in a N-doped lutetium hydride

By: Nathan Dasenbrock-Gammon, Elliot Snider, Raymond McBride, Hiranya Pasan, Dylan Durkee, Nugzari Khalvashi-Sutter, Sasanka Munasinghe, Sachith E. Dissanayake, Keith V. Lawler, Ashkan Salamat & Ranga P. Dias

The absence of electrical resistance exhibited by superconducting materials would have enormous potential for applications if it existed at ambient temperature and pressure conditions. Despite decades of intense research efforts, such a state has yet to be realized. At ambient pressures, cuprates are the material class exhibiting superconductivity to the highest critical superconducting transition temperatures (Tc), up to about 133 K. Over th... more

# Folded floating-gate CMOS biosensor for the detection of charged biochemical molecules

By: Santosh Pandey

A folded floating-gate CMOS biosensor is realized for the detection of charged biochemical molecules. The biosensor comprises a field-effect transistor with a floating-gate, a control-gate, and a sensing area. Charged biochemical molecules placed on the sensing area induce a voltage on the floating-gate and a relative shift in the threshold characteristics. Compared to conventional devices, the floating-gate here is folded to span the entire ... more

# Evidence for suppression of growth of structure

By: Nhat-Minh Nguyen, Dragan Huterer, Yuewei Wen

We present evidence for a suppressed growth rate of large-scale structure during the dark-energy dominated era. Modeling the growth rate of perturbations with the growth index'' γ, we find that current cosmological data strongly prefer a higher growth index than the value γ=0.55 predicted by general relativity in a flat ΛCDM cosmology. Both the cosmic microwave background data from Planck and the large-scale structure data from weak lensing... more

# A primer on twistronics: A massless Dirac fermion's journey to moiré patterns and flat bands in twisted bilayer graphene

By: Deepanshu Aggarwal, Rohit Narula, Sankalpa Ghosh

The recent discovery of superconductivity in magic-angle twisted bilayer graphene has sparked a renewed interest in the strongly-correlated physics of sp2 carbons, in stark contrast to preliminary investigations which were dominated by the one-body physics of the massless Dirac fermions. We thus provide a self-contained, theoretical perspective of the journey of graphene from its single-particle physics-dominated regime to the strongly-correl... more

# Statistical strong lensing. I. Constraints on the inner structure of galaxies from samples of a thousand lenses

By: Alessandro Sonnenfeld

Context. The number of known strong gravitational lenses is expected to grow substantially in the next few years. The combination of large samples of lenses has the potential to provide strong constraints on the inner structure of galaxies. Aims: We investigate the extent to which we can calibrate stellar mass measurements and constrain the average dark matter density profile of galaxies by combining strong lensing data from thousands of lens... more

# Statistical strong lensing. II. Cosmology and galaxy structure with time-delay lenses

By: Alessandro Sonnenfeld

Context. Time-delay lensing is a powerful tool for measuring the Hubble constant H0. However, in order to obtain an accurate estimate of H0 from a sample of time-delay lenses, very good knowledge of the mass structure of the lens galaxies is needed. Strong lensing data on their own are not sufficient to break the degeneracy between H0 and the lens model parameters on a single object basis. Aims: The goal of this study is to determine whether ... more

# Statistical strong lensing. III. Inferences with complete samples of lenses

By: Alessandro Sonnenfeld

Context. Existing samples of strong lenses have been assembled by giving priority to sample size, but this is often at the cost of a complex selection function. However, with the advent of the next generation of wide-field photometric surveys, it might become possible to identify subsets of the lens population with well-defined selection criteria, trading sample size for completeness. Aims: There are two main advantages of working with a comp... more

# Statistical strong lensing. IV. Inferences with no individual source redshifts

By: Alessandro Sonnenfeld

Context. Strong lensing mass measurements require the knowledge of the redshift of both the lens and the source galaxy. Traditionally, spectroscopic redshifts are used for this purpose. Upcoming surveys, however, will lead to the discovery of ∼105 strong lenses, and it will be very difficult to obtain spectroscopic redshifts for most of them. Photometric redshift measurements will also be very challenging due to the blending between lens and ... more

# The dark matter halo masses of elliptical galaxies as a function of observationally robust quantities

By: Alessandro Sonnenfeld, Crescenzo Tortora, Henk Hoekstra, Marika Asgari, Maciej Bilicki, Catherine Heymans, Hendrik Hildebrandt, Konrad Kuijken, Nicola R. Napolitano, Nivya Roy, Edwin Valentijn, Angus H. Wright

Context. The assembly history of the stellar component of a massive elliptical galaxy is closely related to that of its dark matter halo. Measuring how the properties of galaxies correlate with their halo mass can therefore help to understand their evolution. Aims: We investigate how the dark matter halo mass of elliptical galaxies varies as a function of their properties, using weak gravitational lensing observations. To minimise the chances... more

# The effect of spiral arms on the Sérsic photometry of galaxies

By: Alessandro Sonnenfeld

Context. The Sérsic profile is a widely used model for describing the surface brightness distribution of galaxies. Spiral galaxies, however, are qualitatively different from a Sérsic model. Aims: The goal of this study is to assess how accurately the total flux and half-light radius of a galaxy with spiral arms can be recovered when fitted with a Sérsic profile. Methods: I selected a sample of bulge-dominated galaxies with spiral arms. Using ... more

# Strong lensing selection effects

By: Alessandro Sonnenfeld, Shun-Sheng Li, Giulia Despali, Anowar J. Shajib, Edward N. Taylor

Context. Strong lenses are a biased subset of the general population of galaxies. Aims. The goal of this work is to quantify how lens galaxies and lensed sources differ from their parent distribution, namely the strong lensing bias. Methods. We first studied how the strong lensing cross-section varies as a function of lens and source properties. Then, we simulated strong lensing surveys with data similar to that expected for Euclid and measur... more

# The Temperature of Hot Gas in the Universe

By: Eiichiro Komatsu; Yi-Kuan Chiang; Ryu Makiya; Brice Ménard

How hot is the Universe today? How hot was it before? We report on the result of the observational determination of the mean temperature of hot gas in the Universe. We find that the mean gas temperature has increased ten times over the last 8 billion years, to reach about 2 million Kelvin today. As cosmic structures form, matter density fluctuations collapse gravitationally and baryonic matter is shock-heated and thermalized. We therefore exp... more

# Cosmic Birefringence in 2022

By: Patricia Diego-Palazuelos; Johannes R. Eskilt; Eiichiro Komatsu

The observed pattern of linear polarization of the cosmic microwave background (CMB) photons is a sensitive probe of physics violating parity symmetry under inversion of spatial coordinates. A new parity-violating interaction might have rotated the plane of linear polarization by an angle β as the CMB photons have been traveling for more than 13 billion years. This effect is known as "cosmic birefringence." In this paper, we present new measu... more

# New Extraction of the Cosmic Birefringence from the Planck 2018 Polarization Data

By: Yuto Minami; Eiichiro Komatsu

We search for evidence of parity-violating physics in the Planck 2018 polarization data, and report on a new measurement of the cosmic birefringence angle, β. The previous measurements are limited by the systematic uncertainty in the absolute polarization angles of the Planck detectors. We mitigate this systematic uncertainty completely by simultaneously determining β and the angle miscalibration using the observed cross-correlation of the E-... more

# Quantum spin ice in three-dimensional Rydberg atom arrays

By: Jeet Shah, Gautam Nambiar, Alexey V. Gorshkov, Victor Galitski

Quantum spin liquids are exotic phases of matter whose low-energy physics is described as the deconfined phase of an emergent gauge theory. With recent theory proposals and an experiment showing preliminary signs of Z2 topological order [G. Semeghini et al., Science 374, 1242 (2021)], Rydberg atom arrays have emerged as a promising platform to realize a quantum spin liquid. In this work, we propose a way to realize a U(1) quantum spin liquid ... more

# A Generic Topological Criterion for Flat Bands in Two Dimensions

By: Alireza Parhizkar, Victor Galitski

Mutually distorted layers of graphene give rise to a moiré pattern and a variety of non-trivial phenomena. We show that the continuum limit of this class of models is equivalent to a (2+1)-dimensional field theory of Dirac fermions coupled to two classical gauge fields. We further show that the existence of a flat band implies an effective dimensional reduction in the field theory, where the time dimension is removed.'' The resulting two-di... more

# Spin waves and high-frequency response in layered superconductors with helical magnetic structure

By: A. E. Koshelev

We evaluate the spin-wave spectrum and dynamic susceptibility in a layered superconductors with helical interlayer magnetic structure. We especially focus on the structure in which the moments rotate 90∘ from layer to layer realized in the iron pnictide RbEuFe4As4. The spin-wave spectrum in superconductors is strongly renormalized due to the long-range electromagnetic interactions between the oscillating magnetic moments. This leads to a stro... more

# Interplay between superconductivity and magnetic fluctuations in iron pnictide RbEuFe4As4

By: A. E. Koshelev

We consider a clean layered magnetic superconductor in which a continuous magnetic transition takes place inside superconducting state and the exchange interaction between superconducting and magnetic subsystems is weak so that superconductivity is not destroyed at the magnetic transition. An example of such material is RbEuFe4As4. We investigate the suppression of the superconducting gap and superfluid density by correlated magnetic fluctuat... more

# Engineering prethermal symmetric Hamiltonians with polyfractal driving

By: Ivar Martin, Kartiek Agarwal

We construct a dynamical decoupling protocol for accurately generating local and global symmetries in general many-body systems. Multiple commuting and non-commuting symmetries can be created by means of a self-similar-in-time ("polyfractal") drive. The result is an effective Floquet Hamiltonian that remains local and avoids heating over exponentially long times. This approach can be used to realize a wide variety of quantum models, and non-e... more

# Measurements in the Variational Quantum Eigensolver: Fluid Fermionic Fragments and Ghost Pauli Products

By: Seonghoon Choi, Tzu-Ching Yen, Ignacio Loaiza, Artur F. Izmaylov

# On the order problem in construction of unitary operators for the Variational Quantum Eigensolver

By: Artur F. Izmaylov, Manuel Díaz-Tinoco, Robert A. Lang

One of the main challenges in the Variational Quantum Eigensolver (VQE) framework is construction of the unitary transformation. The dimensionality of the space for unitary rotations of N qubits is 4^N−1, which makes the choice of a polynomial subset of generators exponentially difficult process. Moreover, due to non-commutativity of generators, the order in which they are used strongly affects results. Choosing the optimal order in a particu... more

# Possible time-reversal-symmetry-breaking fermionic quadrupling condensate in twisted bilayer graphene

By: Ilaria Maccari, Johan Carlström, Egor Babaev

We study the effective model for superconducting magic-angle twisted bilayer graphene beyond mean-field approximation by using Monte Carlo simulations. We consider the parameter regime where the low-temperature phase is a superconductor that spontaneously breaks time-reversal symmetry. When fluctuations are taken into account, it is shown that a fluctuations-induced phase with a fermion quadrupling order appears, where a different condensate,... more

# Quantum chemistry on quantum annealers

By: Scott N. Genin, Ilya G. Ryabinkin, Artur F. Izmaylov

Quantum chemistry calculations for small molecules on quantum hardware have been demonstrated to date only on universal-gate quantum computers, not quantum annealers. The latter devices are limited to finding the lowest eigenstate of the Ising Hamiltonian whereas the electronic Hamiltonian could not be mapped to the Ising form without exponential growth of the Ising Hamiltonian with the size of the system [J. Phys. Chem. B 122, 3384 (2018)]. ... more

# Cartan subalgebra approach to efficient measurements of quantum observables

By: Tzu-Ching Yen and Artur F. Izmaylov

An arbitrary operator corresponding to a physical observable cannot be measured in a single measurement on currently available quantum hardware. To obtain the expectation value of the observable, one needs to partition its operator to measurable fragments. However, the observable and its fragments generally do not share any eigenstates, and thus the number of measurements needed to obtain the expectation value of the observable can grow rapid... more

# Strongly-Correlated Electron-Photon Systems

By: Jacqueline Bloch et al

An important goal of modern condensed matter physics involves the search for states of matter with new emergent properties and desirable functionalities. Although the tools for material design remain relatively limited, notable advances have been recently achieved by controlling interactions at hetero-interfaces , precise alignment of low-dimensional materials and the use of extreme pressures . Here, we highlight a new paradigm, based on con... more

# How to define quantum mean-field solvable Hamiltonians using Lie algebras

By: A.F. Izmaylov and T.C. Yen

Necessary and sufficient conditions for quantum Hamiltonians to be exactly solvable within mean-field (MF) theories have not been formulated so far. To resolve this problem, first, we define what MF theory is, independently of a Hamiltonian realization in a particular set of operators. Second, using a Lie-algebraic framework we formulate a criterion for a Hamiltonian to be MF solvable. The criterion is applicable for both distinguishable and ... more

# Unitary transformation of the electronic Hamiltonian with an exact quadratic truncation of the Baker-Campbell-Hausdorff expansion

By: R. A. Lang, I. G. Ryabinkin, A. F. Izmaylov

Application of current and near-term quantum hardware to the electronic structure problem is highly limited by qubit counts, coherence times, and gate fidelities. To address these restrictions within the variational quantum eigensolver (VQE) framework, many recent contributions have suggested dressing the electronic Hamiltonian to include a part of electron correlation, leaving the rest to be accounted by VQE state preparation. We present a n... more

# Analytic gradients in variational quantum algorithms: Algebraic extensions of the parameter-shift rule to general unitary transformations

By: Artur F. Izmaylov, Robert A. Lang, Tzu-Ching Yen

Optimization of unitary transformations in Variational Quantum Algorithms benefits highly from efficient evaluation of cost function gradients with respect to amplitudes of unitary generators. We propose several extensions of the parametric-shift-rule to formulating these gradients as linear combinations of expectation values for generators with general eigen-spectrum (i.e. with more than two eigenvalues). Our approaches are exact and do not ... more

# Reducing molecular electronic Hamiltonian simulation cost for Linear Combination of Unitaries approaches

By: Ignacio Loaiza, Alireza Marefat Khah, Nathan Wiebe, Artur F. Izmaylov

We consider different Linear Combination of Unitaries (LCU) decompositions for molecular electronic structure Hamiltonians. Using these LCU decompositions for Hamiltonian simulation on a quantum computer, the main figure of merit is the 1-norm of their coefficients, which is associated with the quantum circuit complexity. It is derived that the lowest possible LCU 1-norm for a given Hamiltonian is half of its spectral range. This lowest norm ... more

# Assessment of various Hamiltonian partitionings for the electronic structure problem on a quantum computer using the Trotter approximation

By: Luis A. Martínez-Martínez, Tzu-Ching Yen, Artur F. Izmaylov

Solving the electronic structure problem via unitary evolution of the electronic Hamiltonian is one of the promising applications of digital quantum computers. One of the practical strategies to implement the unitary evolution is via Trotterization, where a sequence of short-time evolutions of fast-forwardable (i.e. efficiently diagonalizable) Hamiltonian fragments is used. Given multiple choices of possible Hamiltonian decompositions to fast... more

# Dynamical Mean-Field Theory for Markovian Lattice Models

By: Orazio Scarlatella, Rosario Fazio, Aashish Clerk and Marco Schirò

Several experimental platforms, such as superconducting circuits or ultracold atomic in optical lattices, nowadays allow to probe many-body physics in unprecedented regimes, such as in non-equilibrium conditions resulting from controlled dissipation and driving, but theoretical techniques for describing those regimes are limited. In this work [1], we introduce an extension of the nonequilibrium dynamical mean-field theory (DMFT) for bosoni... more

# Superconductivity with broken time-reversal symmetry inside a superconducting s-wave state

By: Vadim Grinenko, Rajib Sarkar, K Kihou, CH Lee, I Morozov, S Aswartham, B Büchner, P Chekhonin, W Skrotzki, K Nenkov, R Hühne, K Nielsch, S-L Drechsler, VL Vadimov, MA Silaev, PA Volkov, I Eremin, H Luetkens, H-H Klauss

In general, magnetism and superconductivity are antagonistic to each other. However, there are several families of superconductors in which superconductivity coexists with magnetism, and a few examples are known where the superconductivity itself induces spontaneous magnetism. The best-known of these compounds are Sr2RuO4 and some non-centrosymmetric superconductors. Here, we report the finding of a narrow dome of an s+is′ superconducting pha... more

# Dynamics of photo-induced ferromagnetism in oxides with orbital degeneracy

By: Jonathan B. Curtis, Ankit Disa, Michael Fechner, Andrea Cavalleri, Prineha Narang

By using intense coherent electromagnetic radiation, it may be possible to manipulate the properties of quantum materials very quickly, or even induce new and potentially useful phases that are absent in equilibrium. For instance, ultrafast control of magnetic dynamics is crucial for a number of proposed spintronic devices and can also shed light on the possible dynamics of correlated phases out of equilibrium. Inspired by recent experiments ... more

# Boson Sampling for Generalized Bosons

By: En-Jui Kuo, Yijia Xu, Dominik Hangleiter, Andrey Grankin, and Mohammad Hafezi

We introduce the notion of "generalized bosons" whose exchange statistics resemble those of bosons, but the local bosonic commutator [ai,a†i]=1 is replaced by an arbitrary single-mode operator that is diagonal in the generalized Fock basis. Examples of generalized bosons include boson pairs and spins. We consider the analogue of the boson sampling task for these particles and observe that its output probabilities are still given by permanents... more

# Field theory approach to eigenstate thermalization in random quantum circuits

By: Yunxiang Liao

We use field-theoretic methods to explore the statistics of eigenfunctions of the Floquet operator for a large family of Floquet random quantum circuits. The correlation function of the quasienergy eigenstates is calculated and shown to exhibit random matrix circular unitary ensemble statistics, which is consistent with the analogue of Berry's conjecture for quantum circuits. This quantity determines all key metrics of quantum chaos, such as ... more

# From Quantum Science to Business: Hype vs. Reality

By: AQC team

This presentation reviews basics of quantum mechanics, quantum computing, and quantum sensing with an eye on practical applications, if any, of various quantum technologies. It discusses a realistic roadmap, time scales, and challenges facing this space and is intended for a business audience, C-level executives, and investors considering strategic decisions about engaging with nascent quantum technology (or not). P.S. Supporting video co... more

# Measurement-based time evolution for quantum simulation of fermionic systems

By: Woo-Ram Lee, Zhangjie Qin, Robert Raussendorf, Eran Sela, and V. W. Scarola

Quantum simulation using time evolution in phase-estimation-based quantum algorithms can yield unbiased solutions of classically intractable models. However, long runtimes open such algorithms to decoherence. We show how measurement-based quantum simulation uses effective time evolution via measurement to allow runtime advantages over conventional circuit-based algorithms that use real-time evolution with quantum gates. We construct a hybrid ... more

# Noise-tolerant quantum speedups in quantum annealing without fine-tuning

By: Eliot Kapit and Vadim Oganesyan

Quantum annealing is a powerful alternative model of quantum computing, which can succeed in the presence of environmental noise even without error correction. However, despite great effort, no conclusive demonstration of a quantum speedup (relative to state of the art classical algorithms) has been shown for these systems, and rigorous theoretical proofs of a quantum advantage (such as the adiabatic formulation of Grover's search problem) ge... more

# Engineering higher-temperature superconductivity

By: Andrey Grankin and all

This work reviews our recent theoretical ideas along with related experimental results related to engineering non-equilibrium protocols and electromagnetic environments to enhance superconductivity in solid-state materials. First, I'll discuss a generalization of the Kennes, Millis et al's protocol of using phonon squeezing to strongly enhance superconducting Tc, in particular close to the dynamical lattice instabilities caused by driving. Se... more

# Fractionalized superconductors and topological orders

By: Mehdi Kargarian

​​​​​​​Integer quantum Hall effect, Chern insulators, topological insulators, and  topological superconductors are famous examples of topological phases in noninteracting or weakly correlated electron systems. In these states  the ground state is nondegenerate and the excitations carry the original quantum  numbers. Fractional quantum Hall effect (FQHE) and spin liquids, on the other hand, arise in strongly correlated electron systems an... more

# Spin-plasma waves

By: Dmitry Efimkin and Mehdi Kargarian

The surface of a topological insulator hosts Dirac electronic states with the spin-momentum locking, which constrains spin orientation perpendicular to electron momentum. As a result, collective plasma excitations in the interacting Dirac liquid manifest themselves as coupled charge- and spin-waves. Here we demonstrate that the presence of the spin component enables effective coupling between plasma waves and spin waves at interfaces between ... more

# Equatorial magnetoplasma waves

By: Cooper Finnigan, Mehdi Kargarian, Dmitry K. Efimkin

Due to its rotation, Earth traps a few equatorial ocean and atmospheric waves, including Kelvin, Yanai, Rossby, and Poincare modes. It has been recently demonstrated that the mathematical origin of equatorial waves is intricately related to the nontrivial topology of hydrodynamic equations describing oceans or the atmosphere. In the present work, we consider plasma oscillations supported by a two-dimensional electron gas confined at the surfa... more

# Efficient Quantum Circuit Preparation of Resonating Valence Bond States

By: Byungmin Kang, Vito W Scarola, Kwon Park

When studying strongly correlated systems using quantum circuits, it is important to prepare good initial states from which the target many-body states can easily be accessed. Here, we discuss an efficient quantum circuit preparation of the resonating valence bond (RVB) state, which plays an essential role in understanding the high-Tc superconductivity and the spin liquid physics. It is known that the RVB state is given by the Gutzwiller proj... more

# Interplay of superconductivity and dissipation in quantum Hall edges

By: Noam Schiller, Barak A. Katzir, Ady Stern, Erez Berg, Netanel H. Lindner, Yuval Oreg

Systems harboring parafermion zero-modes hold promise as platforms for topological quantum computation. Recent experimental work (Gül et al., arXiv:2009.07836) provided evidence for proximity-induced superconductivity in fractional quantum Hall edges, a prerequisite in proposed realizations of parafermion zero-modes. The main evidence was the observation of a crossed Andreev reflection signal, in which electrons enter the superconductor from ... more

# Scar states in a system of interacting chiral fermions

By: I. Martin, K. A. Matveev

We study the nature of many-body eigenstates of a system of interacting chiral spinless fermions on a ring. We find a coexistence of fermionic and bosonic types of eigenstates in parts of the many-body spectrum. Some bosonic eigenstates, native to the strong interaction limit, persist at intermediate and weak couplings, enabling persistent density oscillations in the system, despite it being far from integrability.

# Exact wave-function dualities of quantum spin liquids

By: Shankar Balasubramanian (MIT), Ashvin Vishwanath (Harvard) et al

We study a general class of easy-axis spin models on a lattice of corner sharing even-sided polygons with all-to-all interactions within a plaquette. The low energy description corresponds to a quantum dimer model on a dual lattice of even coordination number with a multi dimer constraint. At an appropriately constructed frustration-free Rokhsar-Kivelson (RK) point, the ground state wavefunction can be exactly mapped onto a classical vertex m... more

# Interaction-driven breakdown of dynamical localization in a kicked quantum gas

By: David Weld (UCSB) et al

Quantum interference can terminate energy growth in a continually kicked system, via a single-particle ergodicity-breaking mechanism known as dynamical localization. The effect of many-body interactions on dynamically localized states, while important to a fundamental understanding of quantum decoherence, has remained unexplored despite a quarter-century of experimental studies. We report the experimental realization of a tunably-interacting ... more

# Casimir effect across a phase transition

By: Andrew Allocca (Cambridge, UK) et al

We propose the Casimir effect as a general method to observe Lifshitz transitions in electron systems. The concept is demonstrated with a planar spin-orbit coupled semiconductor in a magnetic field. We calculate the Casimir force between two such semiconductors and between the semiconductor and a metal as a function of the Zeeman splitting in the semiconductor. The Zeeman field causes a Fermi pocket in the semiconductor to form or collapse by... more

# Moiré Gravity and Cosmology

By: Alireza Parizhkar

The vacuum catastrophe is a fundamental puzzle, where the observed scales of the cosmological constant are many orders of magnitude smaller than the natural scales expected in the theory. This work proposes a new bi-world'' construction that may offer an insight into the cosmological constant problem. The model generally includes a $(3+1)$-dimensional manifold with two different geometries and matter fields residing on them. The diffeomorp... more

# Chiral Anomaly in Interacting Condensed Matter Systems

By: Alireza Parhizkar et al

The chiral anomaly is a fundamental quantum mechanical phenomenon which is of great importance to both particle physics and condensed matter physics alike. In the context of QED, it manifests as the breaking of chiral symmetry in the presence of electromagnetic fields. It is also known that anomalous chiral symmetry breaking can occur through interactions alone, as is the case for interacting one-dimensional systems. In this Letter, we invest... more

# Dynamical quantum ergodicity from energy level statistics

By: Amit Vikram, Victor Galitski

Ergodic theory provides a rigorous mathematical description of classical dynamical systems, including a formal definition of the ergodic hierarchy consisting of merely ergodic, weakly-, strongly-, and K-mixing systems. Closely related to this hierarchy is a less-known notion of cyclic approximate periodic transformations [see, e.g., I. Cornfield, S. Fomin, and Y. Sinai, Ergodic theory (Springer-Verlag New York, 1982)], which maps any "ergodic... more

# Strongly-Correlated Electron-Photon Systems

By: Bloch et al

A new paradigm for materials design emerges when a concerted interaction between strongly correlated materials, photons and phonons is established. Here we present some new avenues for the design and control of materials in and out of equilibrium by exploring the formation of strongly hybridized light-matter hybrids that lead the relation of fundamentally new materials functionalities.