deletions | additions       diff --git a/introduction.tex b/introduction.tex  index 3e34089..3857f3f 100644  --- a/introduction.tex  +++ b/introduction.tex 
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TODO: Define the problem: What IS design of correlated materials? Describe the intersection of materials design with correlated materials. Also describe the need for large computable databases.  [Chuck: cite examples where LDA+U doesn't quite construct the correct convex hull -- maybe Gutzwiller could do better.]  % Materials design also necessarily involves handling and organizing large bodies of data since the process of check => machine learning.  To be precise, we can phrase the question of materials design concretely as follows: given a chemical system, determine the crystal structures and electronic properties of all stable compounds formed by the constituent elements. For example, if the chemical system of interest is Li-Fe-P-O, determine all binaries, ternaries and quaternaries and compute their properties (turns out LiFePO$_4$ is a promising battery material). This problem involves coordinating many moving pieces, including structural prediction, determination of thermodynamic stability against competing phases and computation of electronic properties. In this article, we seek to summarize outstanding challenges in the area, especially as it pertains to correlated materials, and propose strategies to solve them.