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Photonic parity projection plays an important role in photonic quantum information processing. Nondestructive parity projections normally require high-fidelity controlled- $Z$ gates between photonic and matter qubits, which can be experimentally demanding. In this paper, we propose a nearly deterministic parity projection protocol on two photonic qubits which only requires stable matter-photon controlled-phase gates. We also demonstrate that our protocol can tolerate moderate Gaussian phase errors in the controlled-phase gates as well as Pauli errors on the matter qubits. The fact that our protocol does not require perfect controlled- $Z$ gates makes it more amenable to experimental implementation. Although we focus on photonic qubits, our protocol can be applied to any physical system or circuit with imperfect controlled- $Z$ gates. Our protocol also provides a new optimization space for parity projection operations on various physical platforms, which is potentially beneficial for achieving high-fidelity parity projection operations. Published by the American Physical Society2024 

Large-scale tensor network simulations are crucial for developing robust complexity-theoretic bounds on classical quantum simulation, enabling circuit cutting approaches, and optimizing circuit compilation, all of which aid efficient quantum computation on limited quantum resources. Modern exascale high-performance computing platforms offer significant potential for advancing tensor network quantum circuit simulation capabilities. We implement TN-Sim, a tensor network simulator backend within the NWQ-Sim software package that utilizes the Tensor Algebra for Many-body Methods (TAMM) framework to support both distributed HPC-scale computations and local simulations with ITensor. To optimize the scale up in computation across multiple nodes we implement a task based parallelization scheme to demonstrate parallelized gate contraction for wide quantum circuits with many gates per layer. Through the integration of the TAMM framework with Matrix Product State (MPS) tensor network approaches, we deliver a simulation environment that can scale from local systems to HPC clusters. We demonstrate an MPS tensor network simulator running on the state-of-the-art Perlmutter (NVIDIA) supercomputer and discuss the potential portability of this software to HPC clusters such as Frontier (AMD) and Aurora (Intel). We also discuss future improvements including support for different tensor network topologies and enhanced computational efficiency. TN-Sim code can be found on NWQSim: https://github.com/pnnl/NWQ-Sim/tree/tn sim 

Abstract Autophagy, as an intracellular degradation system, plays a critical role in plant immunity. However, the involvement of autophagy in the plant immune system and its function in plant nematode resistance are largely unknown. Here, we show that root-knot nematode (RKN;Meloidogyne incognita) infection induces autophagy in tomato (Solanum lycopersicum) and differentatgmutants exhibit high sensitivity to RKNs. The jasmonate (JA) signaling negative regulators JASMONATE-ASSOCIATED MYC2-LIKE 1 (JAM1), JAM2 and JAM3 interact with ATG8s via an ATG8-interacting motif (AIM), and JAM1 is degraded by autophagy during RKN infection. JAM1 impairs the formation of a transcriptional activation complex between ETHYLENE RESPONSE FACTOR 1 (ERF1) and MEDIATOR 25 (MED25) and interferes with transcriptional regulation of JA-mediated defense-related genes by ERF1. Furthermore, ERF1 acts in a positive feedback loop and regulates autophagy activity by transcriptionally activatingATGexpression in response to RKN infection. Therefore, autophagy promotes JA-mediated defense against RKNs via forming a positive feedback circuit in the degradation of JAMs and transcriptional activation by ERF1. 

Abstract Investigating the impact of galaxy properties on emergent Lyαemission is crucial for reionization studies, given the sensitivity of Lyαto neutral hydrogen. This study presents an analysis of the physical characteristics of 155 star-forming galaxies, 29 with Lyαdetected, and 126 with Lyαnot detected with LyαEW < 20 Å, atz= 1.9–3.5, drawn from the MOSFIRE Deep Evolution Field survey, that have overlapping observations from the Hobby–Eberly Telescope Dark Energy Experiment survey. To unravel the interstellar medium (ISM) conditions in our sample, we developed a custom nebular line modeling algorithm based on the MAPPINGS V photoionization model grid and theemceeframework. Combining nebular-based ISM properties with photometry-based global properties, constrained viaBagpipes, we explore distinctions in the stellar and gas properties between Lyα-detected and Lyα-nondetected galaxies. Our analysis reveals statistically significant differences between the two samples in terms of stellar mass and dust attenuation (A_V) at >2σsignificance, as determined via a Kolmogorov–Smirnov test. Moreover, there are weaker (≲1σsignificance) indications that the ionization parameter and metallicity differ between the two samples. Our results demonstrate that the escape fraction of Lyα( $f_{\mathrm{esc}}^{\mathrm{Ly}\alpha }$ ) is inversely correlated with stellar mass, star formation rate, and dust attenuation, while it is positively correlated with the ionization parameter, with significance levels exceeding 2σ. Our findings suggest that the interstellar environments of Lyα-detected galaxies, characterized by low mass, low dust, low gas-phase metallicity, and high ionization parameters, play a pivotal role in promoting the escape of Lyαradiation. 

Abstract We present cosmological-scale three-dimensional neutral hydrogen (Hi) tomographic maps atz= 2–3 over a total of 837 deg²in two blank fields that are developed with Lyαforest absorptions of 14,736 background Sloan Digital Sky Survey (SDSS) quasars atz= 2.08–3.67. Using the tomographic maps, we investigate the large-scale (≳10h⁻¹cMpc) average Hiradial profiles and two-direction profiles of the line-of-sight (LOS) and transverse directions around galaxies and active galactic nuclei (AGNs) atz= 2–3 identified by the Hobby–Eberly Telescope Dark Energy eXperiment survey and SDSS, respectively. The peak of the Hiradial profile around galaxies is lower than the one around AGNs, suggesting that the dark matter halos of galaxies are less massive on average than those of AGNs. The LOS profile of AGNs is narrower than the transverse profile, indicating the Kaiser effect. There exist weak absorption outskirts at ≳30h⁻¹cMpc beyond Histructures of galaxies and AGNs found in the LOS profiles that can be explained by the Higas at ≳30h⁻¹cMpc falling toward the source position. Our findings indicate that the Hiradial profile of AGNs has transitions from proximity zones (≲a fewh⁻¹cMpc) to the Histructures (∼1–30h⁻¹cMpc) and the weak absorption outskirts (≳30h⁻¹cMpc). Although there is no significant dependence of AGN types (type 1 vs. type 2) on the Hiprofiles, the peaks of the radial profiles anticorrelate with AGN luminosities, suggesting that AGNs’ ionization effects are stronger than the gas mass differences. 

Abstract We used data from the Hobby–Eberly Telescope Dark Energy Experiment (HETDEX) to study the incidence of AGN in continuum-selected galaxies at z ∼ 3. From optical and infrared imaging in the 24 deg 2 Spitzer HETDEX Exploratory Large Area survey, we constructed a sample of photometric-redshift selected z ∼ 3 galaxies. We extracted HETDEX spectra at the position of 716 of these sources and used machine-learning methods to identify those which exhibited AGN-like features. The dimensionality of the spectra was reduced using an autoencoder, and the latent space was visualized through t-distributed stochastic neighbor embedding. Gaussian mixture models were employed to cluster the encoded data and a labeled data set was used to label each cluster as either AGN, stars, high-redshift galaxies, or low-redshift galaxies. Our photometric redshift (photo z ) sample was labeled with an estimated 92% overall accuracy, an AGN accuracy of 83%, and an AGN contamination of 5%. The number of identified AGN was used to measure an AGN fraction for different magnitude bins. The ultraviolet (UV) absolute magnitude where the AGN fraction reaches 50% is M UV = −23.8. When combined with results in the literature, our measurements of AGN fraction imply that the bright end of the galaxy luminosity function exhibits a power law rather than exponential decline, with a relatively shallow faint-end slope for the z ∼ 3 AGN luminosity function.