Alright, so relative to what I'm learning about and relative to a presentation I'm developing with a friend, I thought I'd give an introduction to and a mind-blowing example of a basis of Quantum Mechanics. This, as the title suggests, is called the Heisenberg Uncertainty Principle. And this is also where physics leaves the realm of something called Classical physics and enters the realm of Quantum and Theoretical physics. Beyond Atomic (and some of Particle) physics, everything becomes theoretical or approximate. A large majority of theoretical and quantum physics is not based on physical instances, but rather based on probabilities; well, if you are a Copenhagen-ist. The Copenhagen theory is that all particles have a wavelength associated with them, and that upon observation that wavelength collapses (in fact that wavelength isn't real. It's just an interpretation of the probability that a particle will have any one particular value in any one instance). Observation doesn't just mean looking at something, it means that when the particle interacts physically with another particle that has been "observed" in some fashion, it collapses the wavefunction (the wavelength).
Take this test:
1) Without moving, look in front of you.
--Congratulations! You passed the first part! What you are doing when you look forward is the photons (which technically have not been observed yet) interact with the particles in front of you (that also technically have not been observed yet) and then you are "observing" them. You may already be confused. You may be asking Why can an unobserved particle, upon interacting with another unobserved particle, be observed and collapse both wavefunctions? The answer is initially easy, but very hard to wrap your mind around when you really think about it. Wavefunctions can "entangle" with each other, meaning that even though the photon in the previous explanation may not be touching the particle when the photon is observed, but the wavefunction of the photon is "entangled" with the wavefunction of the particle. So the collapse of the photon leads to the collapse of the particle (otherwise the particle would just appear nonexistant). This is called a Von Neumann chain, which is the idea that observing something that has entangled with another unobserved particle can, upon observation, collapse both wavefunctions.There is one really cool implication about this, which pertains to how far back a Von Neumann chain can go. Considering the speed of photons (travelling at the speed of light), it doesn't take long for a normal Von Neumann (hereby referred to as a VN) chain to collapse, as the photons involved travel relatively quickly. However, there is no limit to how long a VN chain can go on. It is possible (but not probable) that there are enough unobserved elements in a system to have a VN chain several minutes in delay (meaning that the first unobserved particle-unobserved particle interchange happened a few minutes ago, but only now is just observed). If you think about it, the particle wasn't collapsed a few minutes ago. But when you observe the tail end of the VN chain, that particle is instantly observed and "created". Think about it, aren't you creating history? If the particle didn't exist in a certain state let's say 3 minutes ago, and you observed it now, which makes the particle (through the VN chain) collapse back to 3 minutes ago, didn't your observance create its existence? Technically yes.
2) Without moving, don't look behind you.
--Easy right? Well think about this now. Is there a "behind you"? Is there that "scary monster" behind you that will "Sneak up on you and eat your soul if you don't send this email to 20 more people."? Well something has to be observed to exist right (under Copenhagen theory)? And if you are not observing what is behind you, how do you know it is there?
Spoiler:
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It's actually there. Don't worry.
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The photons that are entangling with all the particles behind you are hitting the back of your head. Remember how I stated what observation was? Still applies here. So yes, everything behind you does exist.
All of this is just based on probability. Weird, huh? Heisenberg (and Von Neumann) are really fascinating sometimes. And sometimes you just have to wonder whether they said all this just to mess with people's minds...
Anyway, thank you for reading/hopefully enjoying. You know what to do! Comments, questions, etc, all go in that little comment function below the post or you can send them straight to my Facebook!
Thanks!
--J
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