I am reading the recently published paper from DeepMind, "Neural Scene Representation and Rendering" and especially its "Supplementary Materials".
Following is the page 1 and it's pretty hard for me to derive the upper-bound $F(\theta, \phi)$ equal to $-L(\theta) + \sum KL_{divergence}$
I think there might be more implicit steps to get to the conclusion but can't find something nicely fit deriviation passage.
Any help or advice would be appreciated.
