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Quantum Weirdness

Schrodinger’s Cat. Quantum Weirdness. and the Death of Realism. An Epic Poem. Dear Cecil: Cecil, you're my final hope Of finding out the true Straight Dope For I have been reading of Schroedinger's cat But none of my cats are at all like that. This unusual animal (so it is said)

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Quantum Weirdness

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  1. Schrodinger’s Cat Quantum Weirdness and the Death of Realism

  2. An Epic Poem... Dear Cecil: Cecil, you're my final hope Of finding out the true Straight Dope For I have been reading of Schroedinger's cat But none of my cats are at all like that. This unusual animal (so it is said) Is simultaneously live and dead! What I don't understand is just why he Can't be one or other, unquestionably. My future now hangs in between eigenstates. In one I'm enlightened, the other I ain't. If you understand, Cecil, then show me the way And rescue my psyche from quantum decay. But if this queer thing has perplexed even you, Then I will and won't see you in Schroedinger's zoo. --Randy F., Chicago

  3. An Epic Reply... Dear Randy: Schroedinger, Erwin! Professor of physics! Wrote daring equations! Confounded his critics! (Not bad, eh? Don't worry. This part of the verse Starts off pretty good, but it gets a lot worse.) When saw that the theory that Newton'd invented By Einstein's discov'ries had been badly dented. What now? wailed his colleagues. Said Erwin, "Don't panic, No grease monkey I, but a quantum mechanic. Consider electrons. Now, these teeny articles Are sometimes like waves, and then sometimes like particles. If that's not confusing, the nuclear dance Of electrons and suchlike is governed by chance! No sweat, though--my theory permits us to judge Where some of 'em is and the rest of 'em was." Not everyone bought this. It threatened to wreck The comforting linkage of cause and effect.

  4. E'en Einstein had doubts, and so Schroedinger tried To tell him what quantum mechanics implied. Said Win to Al, "Brother, suppose we've a cat, And inside a tube we have put that cat at-- Along with a solitaire deck and some Fritos, A bottle of Night Train, a couple mosquitoes (Or something else rhyming) and, oh, if you got 'em, One vial prussic acid, one decaying ottom Or atom--whatever--but when it emits, A trigger device blasts the vial into bits Which snuffs our poor kitty. The odds of this crime Are 50 to 50 per hour each time.

  5. The cylinder's sealed. The hour's passed away. Is Our pussy still purring--or pushing up daisies? Now, you'd say the cat either lives or it don't But quantum mechanics is stubborn and won't. Statistically speaking, the cat (goes the joke), Is half a cat breathing and half a cat croaked. To some this may seem a ridiculous split, But quantum mechanics must answer, "Tough @#&! We may not know much, but one thing's fo' sho': There's things in the cosmos that we cannot know. Shine light on electrons--you'll cause them to swerve. The act of observing disturbs the observed-- Which ruins your test. But then if there's no testing To see if a particle's moving or resting

  6. Why try to conjecture? Pure useless endeavor! We know probability--certainty, never.' The effect of this notion? I very much fear 'Twill make doubtful all things that were formerly clear. Till soon the cat doctors will say in reports, "We've just flipped a coin and we've learned he's a corpse."' So saith Herr Erwin. Quoth Albert, "You're nuts. God doesn't play dice with the universe, putz. I'll prove it!" he said, and the Lord knows he tried-- In vain--until fin'ly he more or less died. Win spoke at the funeral: "Listen, dear friends, Sweet Al was my buddy. I must make amends. Though he doubted my theory, I'll say of this saint: Ten-to-one he's in heaven--but five bucks says he ain't." --CECIL ADAMS

  7. Is the World What it Seems? • The classical world (prior to 1900) consisted of: • waves • particles • forces • Let’s tour this familiar terrain...

  8. A place for everything and everything in its ... • Light - an enduring mystery revealed! (go to applet on slit-interference) • Atoms - small but “true”! • May the force(s) be with you! The physical universe - understandable in terms of waves, particles and forces!

  9. Just when Physicists thought they had it made! • Lord Kelvin’s Two Dark Clouds! • The Michelson-Morley expt • BlackBody Radiation hey - now that you mention it...

  10. other strange findings... • photoelectric effect • atomic spectra • Compton scattering

  11. The Great Heresy! • A wave “is a particle” • A particle “is a wave” The Schroedinger Equation and Heisenberg’s Matrix Mechanics... ...a fundamental blurring of the universe

  12. It looks like Heisenberg - I think, I’m pretty sure, I’m not certain... • The UncertaintyPrinciple

  13. The Copenhagen Interpretation... • QM is a complete theory that tells us that the world, at the quantum level, is governed by statistical law. It rules out “classical” or “naïve” realist views of nature. As an example, consider the following applet demonstrating the Hydrogen atom.

  14. The EPR Effect, Bell’s Theorem and Quantum Weirdness • GOD does not play dice! • Hidden Variable Theories and Bell’s Theorem • The Death of classical (perhaps even critical?) realism • Anti-realism and other interpretations of QM

  15. And the Winner Is ... • The majority (by far) of physicists subscribe to the Copenhagen interpretation(s) of QM. This is the dominant paradigm for physics and it is difficult (butnot impossible) for other views to be put forward.

  16. Ironic isn’t it... • In Kuhnian terms, with the entrenchment of a paradigm, foundational questions are pushed aside and most physicists spend their time elaborating the paradigm. The irony is that QM is the most successful theory ever devised and, as it is daily confirmed, it further entrenches the paradigm that assures us that there is no deep reality. It will only be questioned when anomolies begin to emerge and so far none have! When pushed, most physicists adopt an intrumentalist position - QM is just a tool for predicting - not explaining.

  17. Some Questions ... • QM - regardless of the interpretation that you choose - radically alters our conception of what "physical reality" entails. If you adopt the stance that Theology also speaks about reality (including the physical) does QM pose any challenges for Theology? • if the world is indeterministic (or has that built in at some level) does this constrain "god" - does this "push" in the direction of Process Theology?

  18. Some Questions ... • Could "god" operate within the indeterminism of QM? (Instead of many worlds - perhaps "god selects" which wavefunction will be promoted etc)

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