Free Superposition by David Walton

head.”
    â€œYou know you can’t do that.” Terry looked at his watch. We were just waiting, talking idly, but of course he was still billing by the quarter hour.
    â€œI know,” I said. “I understand, believe me. But you have to understand me, too. I hate just sitting by and watching while other people determine my fate. It makes me feel like hitting something.”
    The guard opened the door, and Jean Massey came in, breathing hard. “Sorry I’m late,” she said. “It was murder finding parking.” She gave an embarrassed chuckle and glanced at me nervously. “In a manner of speaking.”
    Jean was our expert witness. Obviously, I couldn’t do it, and we needed someone who could explain the science of the case to the jury. I had given Terry a list of colleagues from the NJSC who could effectively speak about quantum concepts, and Jean was the only one who had said yes. She wasn’t ideal, since she was a friend, and thus could be considered less than objective, but she was willing, and she knew what she was talking about, and that counted for a lot.
    We had gone over her testimony before, but Terry still had a tendency to forget key components of the science, or else refer to it using language that made no sense, betraying his lack of basic understanding. That wasn’t necessarily a bad thing—the jurors would be in the same boat, and seeing that he didn’t understand it either would help them connect with him and his questions. But he had to understand it well enough to get the questions right.
    â€œSo, tell me about these resonators again,” Terry said. “I’m having trouble remembering why two spinning doodads smaller than a clipped fingernail are so important.”
    The question seemed to spark Jeannie’s enthusiasm. “One word,” she said. “Superposition. Let’s try explaining it another way. Do you have a coin?”
    Terry rummaged around in his pockets. “Somewhere around here, I think.” Ever since the United States had pulled coins out of circulation, leaving the dollar bill as the lowest legal denomination, metal coins were getting harder to find. Ask my daughters what a nickel or a dime was and they probably wouldn’t know. Finally, Terry came up with an old, blackened penny. “I keep it for luck,” he said.
    Jean flipped the coin up with her thumb, let it fall on the tabletop, and slapped it flat. With her hand still covering it, she asked, “Which side is up?”
    â€œI don’t know,” Terry said, playing along.
    â€œSo, at this point, it could be in either of two states, heads or tails, right?”
    â€œNo,” Terry said. “It’s only in one state. I just don’t know which one it is.”
    Jean grinned. “A true lawyer talking. And as far as the coin is concerned, I’d have to agree with you. But in the quantum world—if this were an electron with two possible spin states, say, instead of a coin—it no longer holds. The electron is actually in both states at the same time. It’s not until you look at it”—she lifted her hand, revealing the head of Abraham Lincoln, barely visible through the grime—“that it resolves into a single state.”
    â€œThat’s just silly,” Terry said. “If you can’t see it, how do you know it’s not already in one of those states, just like the coin?”
    Jean and I traded a look. “Here we go,” I said.
    Jean took a deep breath. “Okay. New example. Imagine there’s a tennis ball bouncing back and forth between these two walls. It never slows down or falls; it just keeps bouncing back and forth endlessly.”
    â€œOkay,” Terry said.
    â€œWe turn off the lights, and you pull out your camera and take a flash picture. What do you see?”
    â€œA green dot, in the air, somewhere between the walls.”
    â€œIs it any more likely to