Eternal plea: for those of us who want to see what the paper's about before downloading it, it's better to link to the abstract at http://arxiv.org/abs/1810.05

Eternal plea: for those of us who want to see what the paper's about before downloading it, it's better to link to the abstract at http://arxiv.org/abs/1810.05338 http://arxiv.org/abs/1810.05338 .