Face of Murder

Zoe knew well enough that the math department at Georgetown had a good stock of professionals, and if they couldn’t figure it out, that meant that this was some serious kind of equation. “It looks like quantum math.”

“That’s what a few of the professors said. But they don’t recognize it as anything that any of them have seen before, or been working on.”

Zoe continued staring at the equation, her mind racing along and through all the complex signs and numbers and letters, trying to find at least an entrance into the pattern. “What other leads do we have?”

Shelley sifted through a few more pages. “I was just getting there when you came in. Let me see… the student’s roommates and friends have all been questioned, as well as his family and teaching staff. He was in an area of the campus which isn’t covered by cameras, right in a dead spot.”

“Convenient,” Zoe sighed. She wished that just once, they would get hold of a case that had been committed in full sight of witnesses or caught on camera. Of course, they didn’t usually call in the FBI for the ones that were easy to solve.

“As for the professor, looks like there were only cameras at the entrance to the parking lot. So many people come in and out of there all day, and we don’t have eyes on one of the pedestrian exits at all. Nothing suspicious caught on camera.”

“No leads at all,” Zoe noted, propping her chin on one hand as she went over the equation for the seventeenth time already. Slower, faster, it wasn’t making much difference. This was like nothing she had ever come across. Far beyond the level that she had studied during her own time in college.

She switched to the other one, the professor. It seemed just the same. What was this?

“What do you want to do first?” Shelley asked, completing her own study of the files.

“Just a second.” Zoe had not even taken the time to check the second victim’s particulars yet, but there was time for that. She took out her notebook and pen and started writing, making quick and sharp indentations on the page as she began to sketch out an initial working. Greek letters, lines, brackets, downward-pointing triangles—all symbols in quantum math had an equivalent meaning that would reveal a number. M divided by t” minus t’, one divided by s’ then added to one divided by s”, and so on and so forth, all to find the value of B¹ which could later be inserted back into another line of the equation to work out the value of another figure.

The workings started easily enough. If the value of M was equal to the value of r’, then the first two lines made perfect sense; but then the third line disrupted it all, and appeared to give a totally different value for M. Fine; she worked it through another way. Perhaps M was, in fact, double the value of r’, which still made enough sense there, and made the third line work—but by the sixth line, the value of M had to be shown to reach zero, and there again it all made no sense.

When Zoe looked up again, she had no idea how much time had passed. At some point, Shelley had sat down opposite her, and was thumbing through something on the screen of her cell.

“This does not make any sense,” Zoe announced.

Shelley looked up, lifting a carefully shaped eyebrow. “You can’t work them out?”

Zoe’s lips flattened into a thin line before she could make herself admit it. “I cannot work them out yet,” she said. “Maybe we are missing some kind of clue. This is definitely all of it? There was not something written on their backs, or arms, or elsewhere?”

“I know as much as you know,” Shelley said. “I’ve been reading up on the professor. Nothing stands out from his academic history, or from what I can see of his personal life that has made it online.”

“Check the photos again,” Zoe suggested, handing her a bundle and picking up some for herself. She pored over the shots, her eyes taking in the angles of bones, the degree at which a leg had bent in death, the length of the rips in their shirts versus the visible strength of the material and its stitching. Nowhere could she see any connection. Not in their heights, weight, their ages—and no hint of any other ink slashed across their skin.

The worrying thing, of course, was that mathematical patterns became easier to predict the more data you had. Two numbers could seem unconnected, any number of possibilities between them, too many to decide on a definite course. Three numbers, well, that would allow one to make more of a case, begin a formula. But that would require another death.

And they certainly didn’t want another death.

“I’ve got nothing,” Shelley said, shaking her head.

“Swap,” Zoe suggested, handing her bundle over and taking Shelley’s in return. “The only thing of note is the angle of the impact on the first victim’s head. The attacker was a little shorter, probably five nine.”