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arXiv · 1510.03776

Towards Trainable Media: Using Waves for Neural Network-Style Training

Michiel Hermans·Thomas Van Vaerenbergh
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Abstract

In this paper we study the concept of using the interaction between waves and a trainable medium in order to construct a matrix-vector multiplier. In particular we study such a device in the context of the backpropagation algorithm, which is commonly used for training neural networks. Here, the weights of the connections between neurons are trained by multiplying a `forward' signal with a backwards propagating `error' signal. We show that this concept can be extended to trainable media, where the gradient for the local wave number is given by multiplying signal waves and error waves. We provide a numerical example of such a system with waves traveling freely in a trainable medium, and we discuss a potential way to build such a device in an integrated photonics chip.

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Michiel Hermans, Thomas Van Vaerenbergh. 2015-09-30. Towards Trainable Media: Using Waves for Neural Network-Style Training. https://arxiv.org/abs/1510.03776

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