论文标题
量子蒙特卡洛计算中的随机结节表面
Stochastic nodal surfaces in quantum Monte Carlo calculations
论文作者
论文摘要
将费米子基态问题视为受约束的随机优化问题，开发了Fermionic Quantum Monte Carlo的形式主义，并未引用试验波函数。交换对称性是通过与新型Walker繁殖相对应的绿色功能中出现的非本地术语强制执行的。通过鼓励形成随机结节表面形成的扩散处理的补充，我们发现可以在不引入明显的偏见的情况下使用步行者取消的近距离扩展，从而减少了稳定计算所需的步行者数量。概念证明的实施被证明为简单的谐波和原子系统提供了稳定的费米基地面状态。
Treating the fermionic ground state problem as a constrained stochastic optimization problem, a formalism for fermionic quantum Monte Carlo is developed that makes no reference to a trial wavefunction. Exchange symmetry is enforced by nonlocal terms appearing in the Green's function corresponding to a new kind of walker propagation. Complemented by a treatment of diffusion that encourages the formation of a stochastic nodal surface, we find that an approximate long-range extension of walker cancellations can be employed without introducing significant bias, reducing the number of walkers required for a stable calculation. A proof-of-concept implementation is shown to give a stable fermionic ground state for simple harmonic and atomic systems.
