The story was a nice forerunner to Silverberg’s “Hawksbill Station.”
Tom departed from the late twentieth century because of its unpleasant political climate, but the description of Barlow’s orginal time reads more as if Anderson got a peek at 2016 Donald Trump.
For many years, I thought this novel was part of Poul’s Time Patrol series, until Bob Hasse mentioned this as one of his favorites that is not in the series. The beginning reminded me of Heinlein’s Glory Road, and the rest is reminiscent of Asimov’s The End of Eternity, both of which captivated me in the summer of 1968. Poul’s book holds up well in that company.
The time-travel connection is slight in this long story, but it is relevant to Joelle. As I read though, I wondered whether the story could have been much more had the time-travel element been taken more to heart.
The title avatar of Anderson’s book is present as one of the portal exploration team members right from the start of the goings-on, but the name avatar isn’t used until the conclusion of the book—and the meaning of the word is the one that predates our modern digital view.