My throat clenched. A laser. Not one of those vicious construction ones, but still strong enough to bubble metal where it struck the corridor wall. That impossibly level screech disturbed me even more than the laser, though. A person’s shout should go up and down. It should quaver, not remain steady as a tuning fork. My briefing said that this universe was exactly the same as our own, only billions of years younger. Where our universe had grown up, built a career, and pushed its kids through college, this universe was still learning to burp. Other than the rotating rings of Wemm Station, the only solid matter in this universe was a hailstorm of hydrogen, pounding out from the primordial Big Bang in a flux of magnetic fields and gravitational ripples. But that abhuman shriek made me wond

