resolve（）函数如何在factanal（）函数中产生因子相关评分？

Question

在R中使用factanal（）函数会产生因子相关性：

> set.seed(500)
> tmp = cbind(rnorm(200,2,1.5),rnorm(200,2,1.5),rnorm(200,2,1.5),rnorm(200,2,1.5),rnorm(200,2,1.5),rnorm(200,2,1.5))
> print(factanal(tmp, 3, rotation="promax"))

Call:
factanal(x = tmp, factors = 3, rotation = "promax")

Uniquenesses:
[1] 0.796 0.889 0.966 0.935 0.740 0.005

Loadings:
     Factor1 Factor2 Factor3
[1,]                  0.441 
[2,]          0.311  -0.114 
[3,]                  0.139 
[4,]                  0.258 
[5,]          0.495         
[6,]  0.999                 

               Factor1 Factor2 Factor3
SS loadings      1.010   0.353   0.300
Proportion Var   0.168   0.059   0.050
Cumulative Var   0.168   0.227   0.277

Factor Correlations:
        Factor1 Factor2 Factor3
Factor1   1.000  -0.128   0.117
Factor2  -0.128   1.000   0.118
Factor3   0.117   0.118   1.000

The degrees of freedom for the model is 0 and the fit was 8e-04 

经过一番挖掘，我发现以下代码产生了因子相关性：

tmat <- solve(tmp$rotmat)
 R <- tmat %*% t(tmat)

有人可以向我解释一下使用旋转矩阵的Solve（）函数如何产生因子相关性得分吗？为何与直接相关的因子得分相比，这会导致不同的因子相关？