How researchers identified a heart condition using telephone metadata and search engines alone

Telephone metadata surveillance likely reveals a lot more information about people and ensnares more Americans than spy agencies and the Obama administration have let on, a new study finds.  In fact, depending how such surveillance is carried out, analyzing telephone metadata could allow agencies to infer Americans' medical diagnoses and firearm purchases, the study found.  The research, published on Monday in the journal  Proceedings of the National Academy of Sciences , calls in