The 迷信quantum kicked rotor is a paradigmatic model system in quantum physics. As a driven quantum system, it features dynamical localization, specifically Anderson localization in momentum space. However, the interacting many-body kicked rotor is believed to break localization. Here, we present evidence for many-body dynamical localization for the Lieb-Liniger version of the many-body quantum kicked rotor. After some initial evolution, the momentum distribution of interacting quantum-degenerate bosonic atoms in one-dimensional geometry, kicked hundreds of times by means of a pulsed sinusoidal potential, stops spreading. Our results shed light on the boundary between the classical, chaotic world and the realm of quantum physics.
生物学Biology
Early germline sequestration in a basidiomycete fungusighl
An inertial confinement fusion experiment, carried out at the National Ignition Facility, has achieved ignition by generating fusion energy exceeding the laser energy that drove the experiment. Prior to the experiment, a generative machine learning model that combines radiation hydrodynamics simulations, deep learning, experimental data, and Bayesian statistics was used to predict, with a probability greater than 70%, that ignition was the most likely outcome for this shot.
化学Chemistry
Artificial farnesol epoxidase enables a concise synthesis of meroterpenoids
In sexual organisms, inheritance of new mutations is highly dependent on the timing of germline definition. Here, we used the fairy ring–forming fungus Marasmius oreades to challenge the general assumption of a late germline separation in the Fungi. We collected mushrooms from different parts of rings over a 7-year period and identified new mutations in different tissues by whole-genome sequencing. We found evidence that fertile and sterile tissues had accumulated different mutations, suggesting that the germ line, destined for spore production, is already defined in the mycelium in this species. Moreover, the germ line carried fewer mutations than sterile tissues, indicating a lower mutation rate. Our findings suggest that early germline sequestration is more widespread than previously considered across multicellular life.
质料迷信Material Sciences
Diffraction of helium and hydrogen atoms through single-layer graphene
Efficient asy妹妹etric epoxidation reactions have been developed for both the head end and tail end double bonds of farnesol, greatly facilitating the synthesis of terpenoid natural products. However, the lack of methods for direct asy妹妹etric epoxidation of the relatively inert internal alkene of farnesol has posed major challenges in the synthesis of many terpenoids. In this study, we describe the engineering of an epoxidase capable of selectively epoxidizing the internal alkene of farnesol with high regioselectivity and enantioselectivity. The resulting epoxidized intermediate has been successfully applied to simplify the synthesis of a variety of meroterpenoids, reducing the total number of synthetic steps by more than half in most cases.
Diffraction of atoms from surfaces provides detailed insights into structures, interactions, and dynamical processes. However, the method is currently limited to measurements in reflection—diffraction through materials has only been demonstrated for subatomic particles and is an outstanding challenge for atoms. In this work, we diffract helium and hydrogen atoms at kilo–electron volt energies through single-layer graphene at normal incidence. Despite the atoms’ high kinetic energy as well as coupling to the electronic system of graphene, we observe coherent scattering. This preservation of coherence was the result of the limited momentum transfer between the projectile and the lattice, resulting from interaction times on the femtosecond scale.
家养智能Artificial Intelligence
Predicting fusion ignition at the National Ignition Facility with physics-informed deep learning
