Andrew Harlan, Technician in the everwhen of Eternity, falls in love and starts a chain of events that could lead to the end of everything.

The director of Hilltop Research Station extinguishes various fires while hosting a donor dinner in the Cretaceous and planning predatory behavior of his own to keep the donor funds flowing, all while ensuring that the mysterious beings known only as the Unchanging remain in the dark about a quagmire of time travel violations.

In 1916, young Henry Yewbeam’s lily-livered cousin tricks him into staring at the Time Twister marble, sending Henry ninety years into the future, where the cousin is still alive at over a hundred years and just as lily-livered as ever. The other children of time, some of whom are endowed with magic powers from an ancestor, are neatly divided into nice kids and horrid kids. There is never a doubt about which is which, although there are plenty of doubts about whether a rational model of time travel underlies the two (or possibly three) time travel instances. Please see the book’s tags for a short discussion of the issues.

In early 1960, Perry Mason author Earl (not Erle) Stanley Gardner and his wife host John W. Campbell, Robert Heinlein, Clifford Simak, Edward Teller, Ronald Reagan, Douglas MacArthur and Jackie Kennedy to discuss a shared dream in which a time-traveling alien requires them to pick one person to eliminate from history as a prerequisite to a final revision of mankind’s history.

Of the 43 children born 1 October 1989 with no gestation period, the eccentric and sometimes cruel billionaire Reginald Hargreeves brought up seven of them and turned them into the super-powered group called the Umbrella Academy when they developed powers. Nearly thirty years later, after Hargreeves dies, the five surviving members of the group gather at their family home. Oh, and: Number Six died some time ago and only Number Four can see him; Number Five disappeared about seventeen years ago, but he’s back (and in his 13-year-old body) after living 45 years in a post-apocalyptic future that’s scheduled to start in eight days.

Five’s plan for the Umbrella siblings to escape the apocalypse by going into the past ends up scattering them throughout different years of Dallas in the 1960s. They manage okay on their own until shortly after 11/22/63, when secondary effects from changes to the timeline cause a nuclear holocaust that can be averted only by recently arrived Five jumping back to 11/15/63 to exert his unique charm into getting the gang to work together.

Alas, Sean Carroll doesn’t pull any punches in his realistic assessment of the kinds of time travel that are or may be possible under the laws of physics as we know them in our universe. Or, as Professor Carroll himself puts it: “. . . podcasting isn’t for the squeamish.” In my layman’s understand of his most excellent explication, time travel aficionados have two physical phenomena on which to hang their Hat Things:

1. Time Dilation: Under the laws of Einstein’s special relativity, a fast traveler who leaves the Earth, zooming around for a while at near light speed before returning, will experience less passage of time than those who stay in the more-or-less fixed reference frame of Earth. How cool is that? Yes, you can travel as far into the future as you like, so long as you have a means of zooming up to a high enough speed and returning. (And according to general relativity, time dilation also occurs inside a high gravitational field, although I didn’t notice a discussion of this sort of time dilation in the podcast.)
2. Closed Timelike Curves: The second hope for time travelers are certain distributions of matter that (according to Einstein’s equations of general relativity) result in directed paths through spacetime in which a traveler along the path is always moving forward through time—and yet completing a full circuit of the path returns the traveler to the starting point in both space and time. That’s the good news. The bad news is that such paths, called closed timelike curves, might only be possible in the presense of infinitely long rotating cylinders or other physical conditions that may be impossible to engineer.

Up in the ITTDB Citadel, many of us found ourselves in a disquieted state at this point in Professor Carroll’s podcast (roughly the two-hour mark). Some went to bed early in a kind of daze; others decided it was time for a long walk through the lonely ice paths that surround the Citdel. But for those with the fortitude to keep their ears glued to the pod, there was a great reward. Carroll had already waded through the swift, waist-high currents of causality, predeterminism, free will, the A Theory of Time, the B Theory of time, and more. But now he was ready to dive into deep, uncharted waters. Yes, now he was ready to leave known physics behind, to talk about branching time that went beyond the Everettian Many Worlds of Schrödinger’s equation, and to consider what kind of a world would be needed to allow stories such as Back to the Future and Looper to consistently hold together. With this in mind, he devices a four-pronged theory that concludes with what he calls Narrative Time. For me, narrative time shares some features with the time model of Asimov’s The End of Eternity (a model that we call Hypertime in our story-tagging system), but it goes far beyond that.

Suffice it to say that when all the Librarians up in the Citadel woke from their sleeps and returned from their treks, we had a celebration that was strident enough to raise Lazurus Long himself from the dead (if he is dead, that is).

After a catastrophic start to Season 2, Q steps in to pluck Picard’s crew and the Borg Queen from certain death only to insert them into a dystopian timeline that Q himself had created via a small change in 2024.

After stopping the JFK-induced apocalypse in Season 2, the six Umbrella siblings return to 2019 where they no longer exist and their still-living father has founded The Sparrow Academy in their stead.