Heaven's mailing address. A former Harvard physicist recently suggested heaven might have a physical location: just beyond the observable edge of the universe, some 273 billion trillion miles away. As you'd expect, the claim ignited a ton of criticism from astronomers who stress that the cosmic horizon isn't a wall, but simply the limit of what light has had time to show us. The debate is about where science ends, where metaphysics begins, and whether the two should ever overlap.
