2019/07/31 by Claudius Hubig, Hubig, Claudius
Physics and Astronomy · #FOS: Physical sciences #Strongly Correlated Electrons (cond-mat.str-el) #cond-mat.str-el
paper · pdf · doi:10.48550/arxiv.1907.13422
11 pages, 1 figure; include reference to recently found adjoint of SVD
arxiv created 2019/09/26 · arxiv updated 2019/09/27
Following the recent preprints arXiv:1903.09650 and arXiv:1906.04654 we comment on the feasibility of implementation of autodifferentiation in standard tensor network toolkits by briefly walking through the steps to do so. The total implementation effort comes down to fewer than 1000 lines of additional code. We furthermore summarise the current status when the method is applied to cases where the underlying scalars are complex, not real and the final result is a real-valued scalar. It is straightforward to generalise most operations (addition, tensor products and also the QR decomposition) to this case and after the initial submission of these notes, also the adjoint of the complex SVD has been found.