One Reflection Suffice

Abstract: Orthogonal weight matrices are used in many areas of deep learning. Much previous work attempt to alleviate the additional computational resources it requires to constrain weight matrices to be orthogonal. One popular approach utilizes many Householder reflections. The only practical drawback is that many reflections cause low GPU utilization. We mitigate this final drawback by proving that one reflection is sufficient, if the reflection is computed by an auxiliary neural network.