Title: Collapse of the Wave Function
Fandom: due South
Pairing: teenage Benton Fraser/Mark Smithbauer
Rating: R
Length: 1200 words
Summary: Principles from physics do not generally carry over to human relationships.
Notes: I've been wanting to write a flashfic instead of plugging away at my long-term projects, so this was fun. Thanks to desireearmfeldt for beta reading!


In his ongoing effort to teach himself more about advanced physics, Benton had been reading about quantum mechanics, among other things Heisenberg's uncertainty principle and the wave function. Knowledge of location, knowledge of velocity: you could have either when the wave function collapsed, but not both, or at least not to any degree of precision. At its most extreme, this led to the thought-experiment of Schrödinger's cat, which lay in its closed box, in some arcane state of being simultaneously dead and alive. You couldn't know which, until you opened it.

Benton couldn't actually imagine a live cat that would not complain viciously at being shut up in a box, but it was the principle that mattered, and it seemed to him that the principle might also apply, in certain circumstances, to human relationships. Miserably, he wished he hadn't looked in the box.

The "box" in question was standing in front of him, not quite meeting his eyes.

"So, you think you'll be back for the holidays?" Benton said with forced cheer.

Mark shrugged, kicking at some loose gravel in the road. "Maybe. But I'll have to work hard. Might not have time."

Which Benton thought was utter hogwash. Of course his parents would insist that he come home--they were only fifteen, after all, and boarding schools had to have holiday breaks. But Mark apparently didn't want to allow even the possibility that they might meet at Christmastime.

"All right." Benton shoved his hands in his pockets, so that he wouldn't fidget. He ached to ask Mark for his address, so he could write to him. It wasn't like he thought Mark would be an ideal correspondent: he'd probably just send scrawled postcards, but Benton wouldn't mind that. He'd have treasured those postcards. But he knew that Mark wouldn't give it to him, knew that even the asking would lead to embarrassment. He felt his cheeks heating up.

"I have to go," Mark said abruptly. He waved awkwardly, and left, striding down the road towards his parents' house. Benton watched him go.

Three days ago, Mark would've given him a hug: a rough, one-armed, sideways hug, but still a hug.

Benton looked towards his grandparents' cabin, then walked in another direction, through the soggy muskeg toward the hill to the east of their cabin. He couldn't stand to go home yet. In his mind, the scene played again.

They had been down by the river, he and Mark, in the shed where the Smithbauers kept their fishing equipment and canoe and various odds and ends that nobody used any more. Mark had triumphantly produced a bottle of some undefined alcoholic liquid, and insisted they get drunk. Benton had looked at it dubiously, wondering what the probability was that there was methanol mixed in, then he'd fatalistically taken a sip. He wasn't good at saying no to Mark.

It hadn't been the first time they'd drunk together, but the other couple of times had been beer. The stuff in the bottle, whatever it was, had kicked in quicker than Benton had thought, and he'd felt his head gently beginning to spin. Every movement seemed exaggerated, and yet his mind had felt clear. He'd stared at Mark's hands on the bottle, blunt and strong, and at his throat as he leaned his head back for a sip. Pale and smooth and soft-looking, his muscles working as he swallowed.

It would be unthinkable to touch him there. Some parts of the body you could touch, in some ways and in some situations. A pat on the back, a punch on the arm: those were almost always acceptable. You could even roll around on the floor, if you were wrestling, or brush your hands gently against someone else's, if it happened by chance.

But to reach out and stroke his finger softly down Mark's neck--never, that would never be something that he could do. It seemed as impossible as flying.

He wanted to, though, so much that it was an ache inside him. And he wondered if Mark might, perhaps, let him. He didn't think so, not really. But there was that niggling little feeling, the one that came whenever Mark held on a little too long when he put his arm around his back after shinny practise, or met his eyes in a certain way, or any of a myriad other little things.

But he couldn't know. Maybe those things were just in his head, just something he wanted to see. He could never know.

Unless he opened that box.

Perhaps it had been the alcohol, although he hadn't really been that drunk, as far as he could tell. Or perhaps it had just been that he was sick of holding back, and Mark would be leaving in a few days anyway and he thought he didn't have much to lose. It was now or never.

And so, like Pandora, Benton had reached out his hand for the forbidden thing. Mark's neck had been so soft under his fingers.

Mark had jumped, stared at him. Benton had snatched his fingers back, stared back like a caribou caught in the headlights.

"I'm not--" Mark had licked his lips. "You know I'm not, right?"

Benton had swallowed, nodded, although to what, he wasn't sure. He could smell the alcohol on Mark's breath.

And next...Benton shied away from it in his mind. He reached the top of the low hill, looked out over the delta and the town spread out before him, and sat down on a rock, one he liked to sit on when he was up here. It was a good place for thinking.

He'd thought Mark was saying no, but it turned out he wasn't. Not to touching, anyway. Benton flushed all over when he remembered the way Mark had touched him, the way he'd touched in return. The taste and feel of Mark's mouth. He closed his eyes and hid his face in his hands, feeling his cheeks grow hot.

And the thing was, Benton wasn't even sure it was what he wanted. He'd had, well, an orgasm, it was true, but it had been so awkward and strange. Was that what sex was supposed to be like? Maybe you got used to it. It was such a very physical thing: wet, and sticky, and it exposed parts of you that were usually so very private. It was just...not what he expected, although he didn't know what it was he had expected.

And now Mark wouldn't look him in the eye, and Benton was pretty sure they weren't going to keep in touch. He'd thought Mark would either want it or he wouldn't--not this in-between thing where he first seemed to want it and then he acted like Benton carried the plague or something.

He'd thought that when he opened that box, he'd know, one way or another, how Mark felt. But humans weren't like quantum mechanical systems, after all. Apparently they were quite capable of being two contradictory things at once.