  A simple approach to estimation of the ground state energy of quantum
antiferromagnets is developed, based on the approximation that quantum
fluctuations around different bonds are independent. The ground state energy
estimates are as good as spin wave theory or slightly better. A canonical
transformation of the spin operators to generate bond quantum fluctuations is
devised and applied to the classical ground state of the $S=\frac{1}{2}$
Heisenberg model on the square lattice. This simple picture of quantum spin
fluctuations might be useful in more complex models. The resulting nearest
neighbor and next-nearest neighbor correlations can be used in an alternative
derivation of spin waves in the Heisenberg model, giving an accurate dispersion
as well as raising and lowering operators.
