The multiverse is one of science fiction's most beloved conceits—travel far enough, or enter the right wormhole, and you can meet your alter ego in another universe. But granting parallel universes even exist, will we ever be able to reach them? Leading physicists weigh in with their own idiosyncratic thoughts—which are, as usual, highly entertaining.

Deaths in conflict have fallen (slightly), emissions have not risen for a third year and fewer people are dying from disease 

There's no fundamental shift in US policy, but Kerry's remarks suggest that the US is opposed to Israel as a Jewish state as part of a two-state solution, says Phyllis Bennis of

In the first of many discussions on the implications of a Trump presidency, we analyze how the city should respond to what many believe will be a Justice Department openly hostile to