After more than 40 years that included five long-running TV series (even an animated version) and a string of movies, the writers of the latest Star Trek blockbuster in theaters decided to move to a new universe—one that has created fresh opportunities for stories and the chance to modernize and update the franchise. In the movie last summer Kirk, Spock and the rest of the gang were back. But a critical change—a time-jumping, revenge-seeking mad­man who caused the death of Kirk’s father and then destroyed the planet Vulcan—shattered the well-trod timeline of events that longtime fans have come to know so well.

Many Star Trek fans, old and new, like the new, parallel universe, which is intriguingly darker and gives beloved characters and the too-good-to-be-interesting Starfleet a helpful kick-start for future movies. One thing that struck me, however, was how similar the two universes actually were, aside from the cataclysms that brought forth the new timeline. They had the same starring roles (albeit with new, younger actors) and revolved around the same key worlds, the same Federation of Planets, and so on.

In science, as opposed to science fiction, parallel universes aren’t necessarily so parallel. Beyond simple changes in character development, alternative universes may have wholly different laws of physics. Nevertheless, a number of them could prove to be congenial to life, which so far seems to be so rare in our own reality. According to prevailing cosmological theory, our universe spawned from a microscopic region of a primordial vacuum in a burst of exponential expansion called inflation; the vacuum may produce other universes as well. In numerous other universes, theorists long held, the laws of physics may not permit the formation of matter or galaxies as we know them—leaving our home unique.

But recent studies by Alejandro Jenkins and Gilad Perez, authors of our cover story, “Looking for Life in the Multiverse,” show that some other universes may not be so inhospitable after all. “We have found examples of alternative values of the fundamental constants, and thus of alternative sets of physical laws, that might still lead to very interesting words and perhaps to life,” they write. In other words, scientists get a “disaster” for life if their models vary just one “constant” of nature, but if they vary more than one they can find values that are compatible with the formation of complex structures and perhaps intelligent life. What would these universes be like?

Many of us are captivated by the search for other beings in the vast cosmos beyond Earth. So it is ironic that we sometimes place such a paltry value on life that already exists on our own planet. Seven horrific tropical diseases, mostly caused by parasitic worms, ruin the lives and health of a billion impoverished people around the world by making them chronically sick, yet these ailments get less attention and money than HIV/AIDS, malaria and tuberculosis. In his feature article, Peter Jay Hotez presents “A Plan to Defeat Neglected Tropical Diseases.” Surely there is a way to provide the necessary drugs—which can cost just 50 cents per person—so that all people can thrive.