Spin

Local and Global Spin

tdg.observable.spin.spin(ensemble)

The local spin density. Configurations, then sites, then spin direction. That makes it easy to do something with ensemble.s[...,1]. The spin direction matches the index of tdg.PauliMatrix[1:] so that 0 is in the x direction, for example.

tdg.observable.spin.Spin(ensemble)

The total spin, summed over sites. Configurations slowest, then spin direction. The spin direction matches the index of tdg.PauliMatrix[1:] so that 0 is in the x direction, for example.

Spin-spin two-point functions

tdg.observable.ss.ss(ensemble)

The (spatial) convolution of \(s^i * s^j\), which plays an important role in spin-spin fluctuation correlators.

Configurations slowest, then (linearized) sites, then i, then j.

tdg.observable.ss.spin_spin_fluctuations(ensemble)

A derived quantity, \(\left\langle (s^i*s^j)_r \right\rangle - \left(\left\langle s^i \right\rangle * \left\langle s^j \right\rangle\right)_r\).

Bootstraps first, then relative coordinate \(r\), then i, then j.