When time is observed to be merely a derivative function of state change, then the whole notion of “time travel” becomes mere fiction.
Its interesting how a science article *only* five years old can become so obsolete so soon. (or later if yer going backwards)
'Time Travel' into the future is a proven fact - as every GPS device factors 'time travel' in. The satellite clocks up in orbit go 'a tad faster'(technical term) than here on earth and have to be constantly adjusted, otherwise aunt Milly would drive into a lake instead of showing up at your house on Christmas. (no jokes, please)
However, as to going Backwards, worm hole or not, that's still a problem. There's the Grandfather Paradox that can't yet be 'solved'.
And not that it matters but I'll still take Hawking over some guys who read comic books, watch Space Ghost reruns and dress in funny costumes. aka, The Mars Society
BTW, Hawking's Black Hole 'mistake' was on the 'Information Paradox'. He admitted he was 'wrong'. [Yes, there's a lot of Paradox's in physics]