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

Independent Bond Fluctuation Approximation to the Ground State of Quantum Antiferromagnets