Disclaimer in part 1. Thanks again to my betas and reviewers!

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Chapter 3

Friday, March 18, 2005

As he entered the math building, Don pulled off his sunglasses and folded them into his jacket pocket. He wasn't looking forward to this meeting, even though he knew it was something he had to do. Charlie needed to hear this from him, even though it was bound to be difficult.

He followed the familiar route up the stairs and down the hallway, stepping around a group of undergraduates who were sitting on the worn tile floor near the faculty mailboxes, animatedly discussing the week's problem set. They reminded him of his study groups from UCLA. He'd enjoyed them not only for the higher grades they resulted in, but the pleasure he got from bouncing ideas back and forth with his classmates. He loved the way in which all of them put together managed to solve the problems in what would have taken them hours or days longer had they worked individually. It was one of the best parts about his job: the way that he could sometimes feel his team working like a single unit, each person's role slotting into place and producing a whole greater than the sum of its parts.

The door to Charlie's office was partially open, letting the sound of the tapping of chalk on a blackboard spill out into the hall. Don paused for a moment in the doorway, watching his brother work. Charlie's brow was furrowed, and he was softly muttering to himself. There was none of that group effort here that he had observed down the hallway. He knew his brother collaborated with other mathematicians and scientists from time to time on various projects, but for the most part he worked alone. And it wasn't just the fact that his brain leapt ahead in ways most people would have been hard put to keep up with. It was something about the nature of the work that lent itself better to solitary pursuit. No teamwork, no feeling yourself part of a larger whole. Don shook his head. It was another one of the ways that the two of them were very different.

He knocked on the open door. "Charlie?"

The tapping of the chalk continued for a few seconds. Then Charlie's head turned, while his hand kept writing. "Don! What are you doing here?"

"I came to see you. Do you have a minute?"

"If you'll give me one second -- " he added a few symbols to the board -- "you will have my full -- " he picked up the eraser and wiped out a good third of the board -- "and undivided--" the string of characters he had been working on expanded across the freshly cleaned space and ended with a series of Greek letters that reminded Don of Fraternity Row down the block -- "attention." Charlie examined the results of his work and nodded, apparently satisfied. "Actually, I'm glad you came by. I was about to give you a call."

"Why, what's up?" Don leaned back against the door frame, folding his arms over his chest.

"I've been doing a little reading about that landslide in San Morento, and I think I found a way to show that it was not caused by human activity. Now, I know that I'm not consulting on the case, but I think you'll still find this very interesting. See, here --"

"Charlie, that's actually what I came to talk to you about."

Before he could expound on that statement, Charlie went on in an excited rush. "Good, because I've already been doing some thinking. Now, I don't have the data from the geotechnical reports, but you said you had a copy, and I'd like to use those numbers to check my work here."

"What do you mean, to check your work? What are you doing?"

"It's called extreme value theory. It's a way to examine events that would normally be classified as outliers and thrown out of the analysis, but nevertheless are important, maybe even more important than the rest of the data. Natural disasters and the stock market are two types of systems can be analyzed using EVT more accurately than traditional methods."

Don sighed. He'd learned long ago that it was best not to try and interfere with the runaway train of Charlie's thoughts unless absolutely necessary. It was only in the last year that he'd realized if he did more than interject the occasional "uh-huh" or "yeah" to keep his brother moving along, he might actually learn something. And since Charlie had been helping him out with a few cases, he'd learned quite a bit. So even though he was dreading the moment when he would have to tell his brother that none of this mattered, he played along for the time being. "How does this extreme value theory work?"

"Well, I've only started to look at it," which probably meant he'd only read one book and half a dozen scientific articles in the time it would take most people to read the Sunday paper, "but the basic idea is that real-life events do not follow a normal distribution as closely as you might think." He drew a bell curve on the chalkboard. "This is a normal distribution. Most events fall around the center, with fewer as you go out towards the tails. Think of plotting the height of everyone on campus, or the daily returns on the stock market. While it generally follows this pattern, when you use real-life data, there are more outliers at both ends--" he redrew the curve so it resembled a short bell with a very wide mouth -- "than you would expect."

"So a normal distribution is only an approximation. How is that 'extreme'?"

"Good question." Charlie started adding points to his graph, talking as he went, and Don had to bite back a smile. For someone who'd been painfully shy most of his life, Charlie was the most outgoing person in the world when he was teaching someone. When Don had first suggested Charlie present his results to the other agents on Don's team, the mathematician had looked petrified until Don suggested he think of it as teaching a class. The approach hadn't gone over well with everyone, particularly the agents who wanted to get to the point as quickly as possible and didn't see the value in the details of the methodology. But it had built up Charlie's confidence, and Don was coming to see that that was as important as the tangible results he had produced.

"It's these points out here," the younger man was saying as he circled a few dots at one end of the bell curve, "that we might be interested in. Specifically, in predicting their existence, even if they haven't occurred yet. For example, on January 27, 1986, the night before a scheduled launch of the Space Shuttle, the temperature at Cape Canaveral reached a low of 50 degrees. That was 15 degrees colder than for any previous launch. Even though no data points existed to show the effects of that particular temperature on the materials that composed the shuttle, EVT could have predicted the failure of some of those materials, and the launch could have been postponed."

"Challenger." That was an event burned into Don's memory. He remembered exactly where he was sitting, in the student union coffeeshop trying to flirt with Becky Anderson, when the announcement came over the television of the tragedy high in the skies over the Atlantic. He remembered the shocked look on her face that mirrored his as they were hit with the mind-numbing realization that even though things like this weren't supposed to happen, they just had. "You mean that could have been prevented?"

Charlie shrugged. "Hindsight is 20/20. The point is, even though the temperature had never gotten that cold before, even though there was no data point to compare it to, the inference could have been drawn. Same thing in San Marento. According to the geologic record, there's no sign of a landslide ever happening in that exact location. But extreme value theory tells us that just because a slide has never happened there doesn't mean that it can't, under the right conditions. And with the data from the geotechnical report, I should be able to show that." He crossed the room to his desk and shuffled through a pile of papers. "All I've had to work with is the topographic map for the area, from which I can calculate the slope at a medium scale, and some general data from the USGS about soil saturation throughout the San Gabriels, and the National Weather Service data from the rain gauges in the area. But if I had the exact figures from the report that the developer for Crescenta Court submitted to the city, I could show it more precisely."

"Yeah, Charlie, about that." Don ran a hand through his hair. "That's what I came down here to tell you."

"Is there a problem with getting the reports? I mean, I know I'm not officially consulting, but -- "

"It's not that. It's that it's not necessary. Look, your extreme value theory is interesting, and it might apply in the right situation, but this isn't it."

"What do you mean?" Charlie asked in a low tone.

'Here it comes,' Don thought. He reached back and shut the door behind him. "I came to tell you that we made an arrest. Brett Rangadar is in custody for willful destruction of property and three counts of manslaughter. They found more evidence at his apartment linking him to the site. I'm sorry, but I can't say any more than that."

Charlie dropped the papers on his desk, not noticing as they slid off the pile and right onto the floor. "You arrested him? But he didn't do anything."

"Look, I know you don't want to think that someone you know is capable of something like this, but the evidence points very clearly to him. He's made incriminating statements in his e-mail, he's got material that matches stuff found on the site…" Don trailed off as his brother took a step towards him, his eyes flashing. "Charlie?"

"Don, he didn't do it. It was a natural disaster." He pointed at the scrawl on the blackboard. "It's something that could have been predicted, or at least anticipated. Have you talked to the developer, or the geologist who did the report?"

"No, not yet, but we will be following up with them later. We've been focusing on the most likely avenue in the case."

"The most obvious, you mean. The neat, tidy, eco-terrorist avenue." He bent down and picked up the maps that had fallen to the floor, slapping them down onto the desk and turning his back.

"Charlie, what has gotten into you? I know you wanted to help this guy out because he's one of Larry's students, but you're going to have to face the facts here."

"I am facing the facts." He whirled around. "They're right there on the board, Don. The facts say it was a natural event. Your railroading of a suspect is not based on the facts."

"Okay, now you're being ridiculous. There's -- there's no railroading going on, there's only following the trail of evidence, which points in one direction. What you've shown me is interesting, and it could be useful on other occasions, just not this one. I'm sorry, but that's the way it is."

Charlie stared at him for a moment. Don fancied he could actually see the gears turning inside his brother's head, as he considered and rejected various responses. Finally his gaze shifted to the clock on the wall behind Don. "I'm sorry, but I have a class in fifteen minutes. We'll have to finish this discussion later."

The cool tone of voice worried him. "Charlie, I'm sorry it turned out this way, but I thought you'd probably rather hear it in person."

He had already turned back to his desk. "You're probably right, Don. We'll have to talk about it later."

Don tried again. "No hard feelings, right?"

"I said I have to get to class." The tone of voice was one Don recognized. It was the same one he used with agents who were taking up his time with something unimportant when there was actual work to be done. It stung.

"Fine. I'll see you later."

Charlie waved a hand dismissively, and Don turned on his heel. He shut the door behind him with a little more force than was necessary, startling the students who were still huddled on the floor at the other end of the hallway. He made for the back stairwell, suddenly feeling the need to get out of the building as soon as possible.

He couldn't figure out why this case was bothering Charlie so much. Sure, he wanted to help out a colleague, but he was taking it a little too personally. He made a mental note to ask Dad if there was anything he should know about, any minefields he had unknowingly wandered into. He'd managed to put his foot in his mouth more than a few times without knowing it, based on the years that he and Charlie hadn't exactly been close. Maybe that lay behind his brother's stubbornness. Maybe once they tightened the case around Rangadar, Charlie would come around.