Chapter 5, in which Wilson does some research...
Wilson spent the rest of the day with patients, rounds and paperwork, but in some spare time between appointments he'd done some research into parallel universes and alternate dimensions and the results were both shocking and (Wilson almost hated to admit it) plausible. He'd stumbled upon an old article on Stanford University's philosophy pages and after a couple of minutes skim reading he was positively astonished. In early 1957, a man named Hugh Everett had completed his PhD studies at Princeton University. Wilson had realised that he could see the very building Everett had been in from his office window. Everett's doctoral thesis was about relative-state formulation of quantum mechanics, and although this meant nothing to him, seeing as he was an oncologist, something half-way down the page caught his eye. It seemed there could be several interpretations of Everett's theories and the most popular was the "many-worlds" scenario, in which every possible outcome of anything can exist at once. Schrodinger's cat was a famous example of this principle in action. Wilson wondered if this was what had happened to him; somewhere, way back in the past, either he, or House, or someone close to them had made a decision which drastically impacted their lives. Wilson cast his mind back to when he'd first met House, wondering if it was something around then, but his musings were cut off by a sharp knock and then House's head poking around the door.
"Everything okay?" he asked, plonking himself down in the chair opposite Wilson. Wilson still couldn't get over the fact that House had been in the Marines and was missing a limb because of it.
Wilson sighed. "Yeah, I've only been dropped into a parallel universe where nothing's the same and no one knows except you, me and Cameron. An average day, really."
"All right, no need to be sarcastic."
"There's always need with you."
House gave a small smile. "So what's the big news? Your research turned up something good, right?"
"How did you-?"
"I know you, you're not just going to sit there and take this, you're almost as curious as me, just nicer when you go after information. It must be something important, otherwise you'd be slumped about half a centimetre further down in your chair."
"You should meet your other self- he might actually get along well with somone for once."
"Bitter and miserable, is he?"
"Yeah. You always were a little... off, but then after your leg, and Stacy leaving... it just got worse. I'm pretty much your only friend and you have big trust issues, especially when it comes to medical decisions involving you."
House's ears had visibly pricked up at the mention of Stacy.
"Stacy... as in lawyer Stacy? My wife? She exists in your world?"
"Yeah, you lived together for five years, until you had the infarction. She authorised the debridement surgery against your will, but it really was the only option, as you'd said no to amputation."
"Wait, where was I when this was all going on?"
"The pain was so bad after the clot was extracted from your thigh that they put you in a coma. Your heart had already stopped from the flood of toxins and electrolytes going back into your blood stream, so it was the safest thing to do."
"Shit." House looked shocked. "You say 'they'. Weren't you around?"
"No, I was at a conference, but Dr Cuddy was the attending on your case. She's Dean of Medicine in my world and was even then. Is she here?"
"Yeah. She's been Dean for about ten years. Personally invited me to apply for this post; I knew her peripherally in college and I think she had the hots for me. But that's all water under the bridge now. I suppose the infarction was the final nail in the coffin of mine and Stacy's relationship?"
"Yes, it was. There was a lot of guilt and resentment, and I think, in the end it was for the best."
"It's weird thinking about this stuff... I honestly can't imagine what I'd do without her."
Now it was Wilson's turn to be shocked. Was House actually being sentimental? Was he openly expressing love and affection for someon other than himself? One decision. One choice. That was the only difference between this House and the one he knew.
House frowned, as though he could hear Wilson's thoughts. "You never told me the fruits of your labours."
"That's true. Believe me, you will be surprised to hear this. It's very close to home." Wilson proceeded to relate all that he'd found out about Hugh Everett and his doctoral thesis. When he'd finished, House seemed impressed.
"It certainly seems conceivable. No idea how you actually go from one decision universe to another, though."
"Me neither, but I noticed something today. All my patients are the same as in my world. They are my current cases, diagnoses, everything."
"Which means," House said. "The only major difference is me and my situation. And seeing as you are in both worlds, in the same role, it must be a decision made long ago, probably before we even met."
"That does make sense," Wilson said. He had an idea formulating in the back of his mind, but it hadn't come to full fruition yet. He would ask House about it later.
"While I'm here," House said. "Fancy coming over for dinner tonight?"
A/N: Read the article that Wilson read here: plato (.) stanford (.) edu/entries/qm-everett/
Also, here's something to freak you out: I came up with the name Everett's Principle completely randomly; it was an utter coincidence that Everett was a real guy, with a real theory, and that that theory happened to be the subject of this story. Yes, I was slightly worried about whether I have psychic powers after researching it.