Shuhul24

But the documentation says that it measure the fidelity between the "circuits". I don't quite get what does it mean to measure the fidelity between circuits instead of quantum states....

Is there any manner that I can measure the quantum relative entropy between two states? Or can I measure trace distance between two quantum states. Also, I believe, the fidelity...

What about trace distance? Can that be evaluated?

But according to the formula of relative entropy I need to evaluate logarithm of a density matrix. How is that possible?

So how can I evaluate trace of a density matrix? `cirq.partial_trace` is something I don't think would work.

I think `tf.linalg.logm` aren't being applied on `tf.RaggedTensor`. Even after using `.to_tensor()` it says the tensor is not a square matrix. How to work around this?

Is it because `tfq.layers.State` returns a non-square density matrix?

I am actually using the output of `tfq.layers.State` which I believe is density matrix of the output quantum state.

The input into the logm is the output of `tfq.layers.State` which is a `tf.RaggedTensor` of shape `TensorShape[1, None]`, which after applying `.to_tensor()` method converts it into a tensor of shape...

Yes exactly.