Saturday, January 13, 2007

Quantum Physics and Jell-o Houses

This is a very strange and somewhat silly short story I wrote after reading too many books on Quantum Physics. I started to grasp the basics, but some things where just seemingly beyond me, so I wrote this in an attempt to explain it to myself.

Quantum Physics is a fascinating subject, even if you’re not into science. Some of the ideas are mindblowing. Well…I’ll let you read on:

“So essentially, quantum particles can exist as a wave a particle or both at the same time.”

I shifted in my chair, glancing at the crude drawing of a guy scratching his head that was etched into my desk. I know how you feel, dude, honestly I do. I raised my hand.

“Yes?” Said the professor, pointing to me…which was odd as I was the only other person in the room.

“I don’t get it.” I said. Congrats Pauli, you’ve just won this year’s “Stating The Obvious” Prize. “How can something be two things at once?”

“Well, that’s the question.” Said the professor with a smile. “The easiest way to think of it is that the wave function of a quantum particle is really more of a…probability. Particles exist as waves until we attempt to observe them, causing the wave form to collapse, and the wave then ‘solidifies’into it’s particle state.”

“So you’re saying we alter them just by looking at them?”

“Exactly!” Said the professor, thinking the penny had dropped…boy was he in for a disappointment. “Basically, Quantum Physics states that things can exist as multiple things, be in multiple places at once…it’s only when we actually attempt to observe them that they become one solid ‘thing’.”

It’s a problem with the way we think. I thought. Our science is based on reductionism. We look at a complex system and break it down into it’s components to see how it works…only then we discover that the components themselves can be broken down. Only when we reach the quantum level, we realize things don’t act like they should. It’s like taking a car apart and looking at all the parts laid out, it makes perfect sense…only when you get out the microscope, its like seeing the parts are really made of bacon and pixie dust. On a quantum level it makes sense…it just doesn’t appear to fit in with everything we already know.

“But that’s impossible.” I said, with the conviction of a man who doesn’t have a clue what he’s talking about. “How can looking at something change it?”

“Ah.” Said the professor. “One of the good questions.”

He started to draw on the blackboard.

“The problem most people have is assuming that we’re separate from the world. We’ve separated the “darkness behind the eyes” from the world at large. It’s “Me” in one corner and “Everything else”…uhh, everywhere else. This isn’t true.”

“It isn’t?”

“Absolutely not. When you get down to the quantum level, there are no definite borders between anything. Right now, you’re part of the chair you’re sitting on, part of the air around you, and in turn part of me and everything else that exists.”

I shifted uncomfortably in my chair…The idea that it was somehow part of me was hard to comprehend. The professor, seeing my confusion, continued:

“Think of it this way, if you cool a crystal down to absolute zero, it becomes totally clear. Light waves would pass through it completely unobstructed. However, warm it up a little and you’d get minor imperfections and opaque spaces in the crystal. From the point of view of the light, the crystal would appear to be empty space, and the imperfections matter in that space…yet both are one and the same thing.”

I raised my hand again. “When did we get to crystals?” I said, leafing through my notes. “I don’t remember them being in the lesson plan.”

“Ok.” Said the professor, the first signs of frustration showing on his face. “Forget the crystal, I was speaking metaphorically, trying to give you an object lesson.”

Ah, I thought. I get it. It’s called “Lies to Children”. You give an example that has nothing to do with the subject at hand, but it’s a lie you can understand. Then through that example, you can get at least an idea of what’s going on with the real subject.

“Right, speaking totally metaphorically,” he said, driving that point home, “imagine a fish in a tank. Water makes up a fish’s universe. However, and this is the point, they don’t know it exists. A fish doesn’t even know it’s wet. But the fish is connected to the water, and the water connected to everything else. Its existence causes a change in the water that affects everything else in it.”

“So when we’re talking about quantum physics, we’re talking about the same thing. We’re all connected by it, but aren’t aware of it?”

“Yes.” Said the professor. “Only the entire universe is our tank”

“It seems…a little far fetched.” I said.

“I agree. Said the professor…but it’s true, and we can prove it.”

“How?” I asked.

“Well, there’s a type of particle made up of two different parts, what these are aren’t important, and I don’t want to confuse you even further…but the point is, each part spins in the opposite direction to the other. One spins clockwise, the other anti-clockwise.”

“And?” I asked, vaguely wondering how particles knew which direction was which.

“Well, here’s the mind-blowing part.” He paused for dramatic effect. “Even when these parts are split up, they will continue to spin in sync. If one changes its direction of spin, the other will change its spin to compensate instantly…regardless of distance. If one half was in your hand, and the other was three galaxies away, they’d match eachother’s spin instantly.”

“Wow.” I said. It was all I can think of to say.

“That’s not all.” Said the professor, smiling. “Really think about it. We know this happens, we can prove it in the lab…but even if these particles where able to communicate in some way, over the distances we’re talking about, that communication would have to break the speed of light, something we know under Newtonian physics to be impossible. It proves reality isn’t local. We’re connected to all things at all times, and effect each other just by existing”

This is insane. I thought. Particles that break the known laws of physics, particles that can be in two places at once, particles that aren’t even particles until you look at them. Something that exists only as a possibility, until you look at it, then it becomes something, like it knows you’re looking. It’s creepy. It’s like looking into a microscope and seeing something looking back.

“But Professor,” I began, “I still don’t get it. Even things I’m definitely connected to can’t be altered just by me looking…and if what you’re saying is true, we’re not talking about a single particle off in space somewhere, we’re talking about everything. Aren’t you basically saying that my foot could be a small nightstand until someone looks at it? That right now my house is just a probability of a house, and could instead be a small lump of Jello until I get home?”

The professor sighed and sat on the corner of his desk. He took an apple from his top drawer and took a bite. He thought for a few moments.

“What you need is a definite example, something you can understand.”

“I’d appreciate it.” I said. “I’m feeling a little dumb here.”

“Don’t be.” Said the professor with a smile as he swallowed a bite of apple. “Even the brightest minds are still arguing over what quanta is all about. People are still arguing about Schrödinger’s Cat.”

Ah, Schrödinger’s cat, one of the few thought experiments I half understand. Basically, you have a cat in a box. In that box you have a phial of poison attached to a Geiger counter. If the counter detects the decay of a radioactive isotope, the poison is released. Schrödinger said that if you put a piece of radioactive material in the box that had a 50/50 chance of decaying during the experiment, because the chances of the ‘trap’ being sprung are 50/50, that under quantum physics, both states can exist at the same time. At any point during the experiment, the radioactive atom has both decayed and not decayed.

So until you open the box and see for yourself “collapsing the waveform” of the particle and forcing it to be one form or another…the cat can be both alive and dead at the same time.

The professor continued, shaking me from my thoughts about the poor cat:

“Ok, here’s one you’ll be able to grasp. This isn’t exactly quantum physics, but it illustrates the point.”

I nodded, hoping I’d finally get it.

“Eventually, the whole universe with grind to a complete stop. All the energy will have been spent and dissipated, and we’ll be left with a few lifeless hunks of rock floating in space. Frozen and immobile. Time will stop.”

“What?” I asked. “Time can’t stop!”

“Of course it can.” Said the professor. “You’re forgetting that we created time, not the other way around.”

“Huh?” I said. It was all I could think of to say.

“Think if it this way. Seconds, Minutes, Hours…technically they don’t exist. We created them to measure time, they’re not time itself. They’re intervals, a space in which for something to happen. Time is really all about perception. Ever noticed how when you’re dreading something time seems to speed up, or slow down?”

“Like when you where a kid and Christmas Eve seemed to last for a few weeks.”

“Exactly!” Said the professor. “Time is just a space for something to happen. If absolutely nothing ever happens, or ever will happen, not even an electron orbiting an atom…time becomes completely and totally meaningless. It stops.”

“Well…yeah.” I said. “But time doesn’t really stop. I mean, if I could travel through time to this future and hang around, I’d perceive time moving forward, even if nothing was moving.”

“And there you’ve made my point for me!” Said the professor.

“I have?” I asked, confused.

“Yes, think about what you’ve just said. Nothing is happening, nothing ever will happen We have a clearly defined state. For all intents and purposes time has stopped. Because no-one is observing it, it will remain in that state forever…”

“Ah!” I said, the penny dropping. “But by me going there and being present, just through me observing that state, I’ve changed it.”

“Absolutely!” Said the professor, beaming. “We had a closed system, and even without you touching anything, you’ve altered it by your very presence. You heart would beat, you’d breathe, you’d think…all events that need time to happen in, so by your presence, in a way, you’ve ‘created’ time and changed the system. We had the universe in one state, frozen, changeless for all eternity, and by you looking at it you’ve changed it…and conversely, once you left, it would change back.”

“I see.” I replied, happily making more notes in my workbook.

“And that,” said the professor, “is the nature of quantum physics. Nothing is really ‘fixed’, reality is subjective, the act of observing these phenomena changes them, and pretty much everything exists only as a probability until it’s observed.”

“So technically, under Quantum Physics, if a tree falls in the woods, it actually doesn’t make a sound if no-one is around to hear it?”

“Possibly.” Said the professor with a smile as he finished his apple. “More likely it makes a sound and doesn’t at the same time.”

“And if I listen to see, me listening would affect the outcome.”

“You’ve got it!”

Note : All the science in the above is true, including the magical spinning particles. Only the stopping of time thought experiment is my own invention, which I thought of to try and explain the concept to myself.

My favorite quote about Quantum Physics is from someone who’s name I can’t remember. To my best recollection, it goes “If Quantum Physics doesn’t scare the crap out of you, you haven’t understood it properly.”


rayray said...

I have just scratched a hole into my head after reading your blog.
Now my brain has flopped out onto the floor.

MC Etcher said...

There are so many inconsistancies when it comes to quantum mechanics that it seems pretty clear that we have no idea how the universe truly works - the current theories seem like just so much doubletalk.