MiniZero: Comparative Analysis of AlphaZero and MuZero on Go, Othello, and Atari Games

This paper presents MiniZero, a zero-knowledge learning framework that supports four state-of-the-art algorithms, including AlphaZero, MuZero, Gumbel AlphaZero, and Gumbel MuZero. While these algorithms have demonstrated super-human performance in many games, it remains unclear which among them is most suitable or efficient for specific tasks. Through MiniZero, we systematically evaluate the performance of each algorithm in two board games, 9x9 Go and 8x8 Othello, as well as 57 Atari games. For two board games, using more simulations generally results in higher performance. However, the choice of AlphaZero and MuZero may differ based on game properties. For Atari games, both MuZero and Gumbel MuZero are worth considering. Since each game has unique characteristics, different algorithms and simulations yield varying results. In addition, we introduce an approach, called progressive simulation, which progressively increases the simulation budget during training to allocate computation more efficiently. Our empirical results demonstrate that progressive simulation achieves significantly superior performance in two board games. By making our framework and trained models publicly available, this paper contributes a benchmark for future research on zero-knowledge learning algorithms, assisting researchers in algorithm selection and comparison against these zero-knowledge learning baselines. Our code and data are available at https://rlg.iis.sinica.edu.tw/papers/minizero.Comment: Submitted to IEEE Transactions on Games, under revie

Kinetics, Energetics, and Size Dependence of the Transformation from Pt to Ordered PtSn Intermetallic Nanoparticles

The outstanding catalytic activity and chemical selectivity of intermetallic compounds make them excellent candidates for heterogeneous catalysis. However, the kinetics of their formation at the nanoscale is poorly understood or characterized, and precise control of their size, shape as well as composition during synthesis remains challenging. Here, using well-defined Pt nanoparticles (5 nm and 14 nm) encapsulated in mesoporous silica, we study the transformation kinetics from monometallic Pt to intermetallic PtSn at different temperatures by a series of time-evolution X-ray diffraction studies. Observations indicate an initial transformation stage mediated by Pt surface-controlled intermixing kinetics, followed by a second stage with distinct transformation kinetics corresponding to a Ginstling-Brounstein (G-B) type bulk diffusion mode. Moreover, the activation barrier for both surface intermixing and diffusion stages are obtained through the development of appropriate kinetic models for analysis of experimental data. Our density-functional-theory (DFT) calculations provide further insights into the atomistic-level processes and associated energetics underlying surface-controlled intermixing

Study on the Antioxidant Activity Hetao Wheat Germ Polypeptides

In this experiment, the peptides were obtained by enzymatic digestion of wheat germ proteins from river sets using neutral protease, trypsin and pepsin. In vitro antioxidant capacity of samples was determined and their polypeptides distribution was determined using polyacrylamide gel electrophoresis (SDS-PAGE). The results showed that germ protein and polypeptides concentrations were positively correlated with antioxidant capacity.The antioxidant capacity of the peptides obtained by enzymatic digestion of neutral protease at different concentrations was significantly higher than that obtained by enzymatic digestion of pepsin and trypsin (P<0.05), and their reducing capacity, 2,2-biazo-bis(3-ethyl-benzothiazole- 6-sulfonic acid) diammonium salt (ABTS+), 1,1-diphenyl-2-picrylhydrazyl (DPPH) clearance was up to (1.17±0.004) 1.0 mg/mL, (84.82%±0.87%) 1.5 mg/mL and (55.01%±0.01%) 1.0 mg/mL, respectivety, and their ABTS+ and DPPH radical scavenging rates were significantly higher than those of germ proteins (p<0.05). In addition, for the hydrolysis capacity of different proteases differs, pepsin had the greatest hydrolysis capacity while neutral protease had the least. The antioxidant capacity of germ protein polypeptides correlated with their molecular weight, but it is not necessarily the case that the smaller the molecular weight of a protein peptide had the better antioxidant effect. The results of these experiments provide a theoretical basis for further research on the antioxidant polypeptides of wheat germ in the Hetao

PT{\cal PT} Symmetry and PT{\cal PT}-Enhanced Quantum Sensing in a Spin-Boson System

Open systems, governed by non-Hermitian Hamiltonians, evolve fundamentally differently from their Hermitian counterparts and facilitate many unusual applications. Although non-Hermitian but parity-time (${\cal PT}$) symmetric dynamics has been realized in a variety of classical or semiclassical systems, its fully quantum-mechanical demonstration is still lacking. Here we ingeniously engineer a highly controllable anti-Hermitian spin-boson model in a circuit quantum-electrodynamical structure composed of a decaying artificial atom (pseudospin) interacting with a bosonic mode stored in a microwave resonator. Besides observing abrupt changes in the spin-boson entanglement evolution and bifurcation transition in quantum Rabi splitting, we demonstrate super-sensitive quantum sensing by mapping the observable of interest to a hitherto unobserved ${\cal PT}$-manifested entanglement evolution. These results pave the way for exploring non-Hermitian entanglement dynamics and ${\cal PT}$-enhanced quantum sensing empowered by nonclassical correlations.Comment: 25 pages, 19 figure