Lazy matrices talk from the IWR school 2017

As mentioned in a previous post on this matter last month, from 2nd to 6th October, the IWR hosted the school Mathematical Methods for Quantum Chemistry, which I co-organised together with my supervisors Andreas Dreuw and Guido Kanschat as well as the head of my graduate school Michael Winckler.

From my personal point of view the school turned out to be a major success, where I had the chance to meet a lot of interesting people and got a bucket of ideas to try out in the future. The feedback we got from the participants was positive as well and so I am very happy that all the effort in the past half a year really turned to be worth the while for all of us.

Even though all relevant documents from the school, including the slides from the lectures and most contributed talks, are finally published at the school's website, I nevertheless want to include a pointer to the slides of my lazy matrices talk from this blog for reference.

The topic and structure of the talk is very similar to the talks of the previous months. I motivate the use of contraction-based methods from the realisation, that storing intermediate computational results in memory can be less optimal than recomputing them in a clever way when needed. Then I present lazy matrices as a solution to the issue that the code needed for performing calculations in the sense of contraction-based methods can become very complicated. Afterwards I hint how we use lazy matrices in the context of the quantum chemistry program molsturm and how molsturm itself really facilitates the implementation of new quantum-chemical methods. For this I show in slide 20 a comparison of parts of a working Coupled-Cluster doubles (CCD) code based on molsturm with the relevant part of the equation for the CCD residual.

Lazy matrices for contraction-based algorithms (IWR school talk)