--- trunk/tengDissertation/Introduction.tex 2006/04/21 05:45:14 2725 +++ trunk/tengDissertation/Introduction.tex 2006/04/21 15:37:53 2726 @@ -831,7 +831,7 @@ $\varphi_1(t)$ and $\varphi_2(t$ respectively , we hav error of splitting method in terms of commutator of the operators(\ref{introEquation:exponentialOperator}) associated with the sub-flow. For operators $hX$ and $hY$ which are associate to -$\varphi_1(t)$ and $\varphi_2(t$ respectively , we have +$\varphi_1(t)$ and $\varphi_2(t)$ respectively , we have \begin{equation} \exp (hX + hY) = \exp (hZ) \end{equation} @@ -846,12 +846,12 @@ can obtain \] Applying Baker-Campbell-Hausdorff formula to Sprang splitting, we can obtain -\begin{eqnarray*} +\begin{equation} \exp (h X/2)\exp (h Y)\exp (h X/2) & = & \exp (h X + h Y + h^2 [X,Y]/4 + h^2 [Y,X]/4 \\ & & \mbox{} + h^2 [X,X]/8 + h^2 [Y,Y]/8 \\ & & \mbox{} + h^3 [Y,[Y,X]]/12 - h^3 [X,[X,Y]]/24 & & \mbox{} + \ldots ) -\end{eqnarray*} +\end{equation} Since \[ [X,Y] + [Y,X] = 0\] and \[ [X,X] = 0\], the dominant local error of Spring splitting is proportional to $h^3$. The same procedure can be applied to general splitting, of the form @@ -1238,7 +1238,7 @@ Q^T Q = 1$, \label{introEquation:orthogonalConstraint} where $I_{ii}$ is the diagonal element of the inertia tensor. This constrained Hamiltonian equation subjects to a holonomic constraint, \begin{equation} -Q^T Q = 1$, \label{introEquation:orthogonalConstraint} +Q^T Q = 1, \label{introEquation:orthogonalConstraint} \end{equation} which is used to ensure rotation matrix's orthogonality. Differentiating \ref{introEquation:orthogonalConstraint} and using