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• Instead of trying to explicitly extract the coordinates of a
datapoint on the manifold, map the datapoint  to an
energy valley in a high-dimensional space.
• The learned energy function in the high-dimensional
space restricts the available configurations to a low-
dimensional manifold.
– We do not need to know the manifold dimensionality
in advance and it can vary along the manifold.
– We do not need to know the number of manifolds.
– Different manifolds can share common structure.
• But we cannot create the right energy valleys by direct
interactions between pixels.
– So learn a multilayer non-linear mapping between the
data and a high-dimensional latent space in which we
can construct the right valleys.