Here is what J. Robert Oppenheimer (Simon J. Williams ’09) says when he hears the death toll at Hiroshima: “Some numbers are so big, multiplying by two doesn’t make a difference.”

That line gets right at the heart of ‘The Space Between,’ a new play at the Loeb Mainstage, conceived and directed by Catherine “Calla” Videt ’08. This incredibly ambitious production is the first student-written play to appear on the Mainstage in 15 years. While Videt’s subject might be theoretical physics, what she’s really interested in are moments where the science is inadequate to explain its own implications; equations may have built the bomb, but they can’t handle the fallout.

Drawing on history, mythology, and a dizzying array of artistic work—everything from Beckett to The Books and Bruno Schulz—Videt has constructed a deep meditation on the bridges people build to one another. It’s a big topic; in the first act, one character teaches a class called “Widely Applied Physics.” When you go to see this show—which you definitely need to do—think of it as Widely Applied Theater.

The central character is Richard Feynman (Jesse W. Barron ’09), a physicist who played a supporting role in the Manhattan Project. Lured to the Nevada desert by Oppenheimer, Feynman divides his time between his work and his wife, who is dying of tuberculosis. Her real name was Arline Greenbaum, but here it’s Eurydice, and Catrin M. Lloyd-Bollard ’08 is appropriately enigmatic and cipher-like in the semi-mythological role.

The show develops out of this central relationship in many directions at once, which makes its grace all the more surprising. Feynman’s memories of Eurydice are brought movingly to life by Matt I. Bohrer ’10, who plays the physicist’s younger self. As Oppenheimer & Co. come closer to perfecting the “destroyer of worlds,” the biblical Adam (David F. “Ricky” Kuperman ’11) and Eve (Sarah T. Christian ’11) arrive to reflect on the Earth’s beginnings. There is also a trapeze.

With an evocative, surreal set by Grace C. Laubacher ’09 and an incredibly complex program of sounds by Josh R. Stein ’09, the show flows and breathes like nothing else I’ve seen at Harvard. It’s sort of a technical miracle, actually. I was told the cast rehearsed six hours a day to make this kind of seamlessness possible. Who knows if that’s fact or exaggeration? It was worth the effort, in any case.

It can be hard to tell where one story ends and another begins, but that’s the point. Videt has a kind of wide-eyed sensibility that sees the world harmonizing with itself at every turn, and the intuitive logic that grounds her thinking is what makes “The Space Between” go. Early on in the first act, two characters discuss quarks, elementary particles born without mass; just like Adam and Eve, one says, “born without sin.”

Oddly enough, the two characters having the conversation are also named Adam (Rory N. Kulz ’08) and Eve (Julia L. Renaud ’09), both students under the tutelage of the older Feynman. They meet in class, they fall in love, they have a baby. Adam, a painter who hasn’t figured out how to grow up, makes a joke about naming the kid Cain. Theirs is the show’s most affecting relationship.

Working in the vague zones where reality, fantasy, and myth overlap, Videt sometimes has trouble writing real people, but with Kulz and Renaud the emotions are tangible and down-to-earth. Things get cheesy sometimes—“This is what it means to love an artist!” is one of Eve’s less successful lines—but Videt is usually better at bodies than words. There is a moment, during an argument, when Renaud throws herself back on a bed before slowly curling in on herself. The gesture, which mixes irritation, helplessness, and deep fatigue, rings true. We’ve all been there.

Of course, the show also spends a lot of time going to places we haven’t been. In the second act, Feynman follows his departed Eurydice to the underworld, where the loudspeaker that greets him turns out to be very funny: “Welcome to Hell! Where the local time is . . . irrelevant.” Tied to nothing but Videt’s own imagination, Feynman’s performance of the Orpheus myth doesn’t work so well—it’s the one time the word “pretentious” skidded across my brain.

It’s not until Oppenheimer and history return to view that Hell makes sense, with a line slyly borrowed and modified from Bertolt Brecht’s “Life of Galileo”: “August 6, 1945: Heaven abolished.”The show doesn’t so much end as dissolve, which is meant as praise. Too often artists use History to de-fang the past—think “Schindler’s List”—but Videt finds resonance in events which remain indeterminate, unknown, and unredeemed. The closing sequence is a magical, literally incandescent experience.

It’s appropriate that the show should open on pre-frosh weekend. With its sincerity and intellectual openness, the show reminded me of those late night dorm conversations that everyone goes through freshman year, when the world seems on the verge of giving up all its secrets. Unlike a stoned freshman, however, Calla Videt knows what she’s talking about. She has real ideas about how people and history work together, and while they’re sometimes fuzzy, they can’t be easily dismissed; I’ve decided to see “The Space Between” again.

—Staff writer Richard S. Beck can be reached at tchi@fas.harvard.edu.