Astronomers built the James Webb Space Telescope to pick up faint light from the first billion years after the Big Bang, a chaotic era when vast swaths of hydrogen and helium gas gathered into the chains of galaxies we see today. Even in the telescope’s first images, astronomers could see a whole zoo of mysterious smears of light. One batch of objects proved especially difficult to interpret.

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In 1973, John Archibald Wheeler described the relationship between space and matter in two sentences: “Space acts on matter, telling it how to move. In turn, matter reacts back on space, telling it how to curve.” Wheeler’s words serve as a pithy encapsulation of general relativity, Albert Einstein’s theory of gravity. Wheeler’s sentences also lay out a challenge that theorists face today: When…

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