Here is the paper: <a href="https://papers.nips.cc/paper/6596-dimensionality-reduction-of-massive-sparse-datasets-using-coresets.pdf" rel="nofollow">https://papers.nips.cc/paper/6596-dimensionality-reduction-o...</a>
This is neat. I bet if you use a hypercircle technique then you could project wikipedia articles into a GiST or BallTree or similar n dimensional tree structure. Then search can be done by projecting a query into the hypercircle and returning results close by.