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Einstein and Schrodinger's Quest for a Unified Theory led to a Titanic Clash

StartsWithABang writes When it comes to the very nature of quantum mechanics — about the inherent uncertainty and indeterminism to reality — it's one of the most difficult things to accept. Perhaps, you imagine, there's some underlying cause, some hidden reality beneath what's visible that actually is deterministic. After all, a cat can't simultaneously be dead and alive until someone looks can it? That's one of the problems that both Einstein and Schrödinger wrestled with during their lives. An investigation of that story, their work on that front, and their friendship that ensued as both pursued that same end is thoroughly investigated here by physicist Paul Halpern.

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  1. The fucking cat by WillKemp · · Score: 4, Informative

    No, of course the cat can't be simultaneously alive and dead - that's Schrödinger's point.

    I wish people would stop crapping on about that fucking cat when they have no idea what it means.

    1. Re:The fucking cat by iris-n · · Score: 4, Informative

      I wish people would stop speculating about the fucking cat and just read what Schrödinger wrote. Come on, it's four paragraphs.

      What Schrödinger is doing is pointing out how ridiculous it is to accept the "quantum blurring" because "it only affects microscopical particles anyway and they're just weird". The problem is that one cannot consistently keep the blurring confined to the atomic domain. As Schrödinger points out very clearly, if we accept that the atomic nucleus is "blurred", then this blurring can be easily amplified to the macroscopic domain and make the cat be simultaneously dead and alive. Since we don't observe cats to be blurred, we cannot accept atomic nucleus to be blurred.

      That's what Schrödinger states one line after introducing the fucking cat. Since I know nobody is gonna click the link and RFTA I'm going to quote:

      It is typical of these cases that an indeterminacy originally restricted to the atomic domain becomes transformed into macroscopic indeterminacy, which can then be resolved by direct observation. That prevents us from so naively accepting as valid a "blurred model" for representing reality.

      --
      entropy happens
    2. Re:The fucking cat by david_thornley · · Score: 4, Informative

      We can't observe "quantum blurring" either. If we do the two-slit experiment with electrons, and measure which electron goes through which hole, they'll act just like particles. It's only if we don't observe electrons as particles that we can get interference patterns. We can't directly observe a particle being in an indeterminate state, but we can measure its state by translating it into something way above the photon level, like a photon detector or a cat. (Under ideal conditions, you've got about a 50% chance of detecting a burst of about 100 photons. This is as close to direct perception on the quantum level as you can get.)

      --
      "When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes
    3. Re:The fucking cat by DMUTPeregrine · · Score: 3, Informative

      Actually, it was that if the Copenhagen interpretation of quantum theory was correct then that would be the absurd conclusion.

      So the Copenhagen interpretation is wrong, as is any other interpretation that necessarily comes to the same absurd conclusion.

      The interpretations that don't make such a conclusion are unaffected by the thought experiment.

      --
      Not a sentence!
  2. Well that was quick. by Anonymous Coward · · Score: 3, Informative

    More hipster site spam from a serial hipster spam poster. Don't even need to read the summary, since it's all clickbait shoddily cooked up from other people's work anyway.

  3. Stupid post modded up yet again by Anonymous Coward · · Score: 5, Informative
    A variation of this post gets copy-pasted to every single article with anything related to quantum mechanics, and inevitably seems to get modded up despite the fact it always gets shown to be completely wrong every time. Typical psuedo-science tactic of repeating things enough times hoping some of the time someone will forget or be too slow replying with the counter-points.

    5. And thus it is detected ALL THE TIME BY EVERYTHING AROUND IT, long before you put it through a diffraction grating, or whatever test you dream up.

    Stop using the pop-sci version of things where it is about being "detected" or not, and it comes down to whether it interacts with things in specific ways. Turns out the fact it has a magnetic field, or even that the wavefunction has infinite extent, doesn't cause it to be "detected" and there are plenty of ways interactions that can happen without "detection," whether with things like the slits in a double slit experiment, or more explicitly involving magnetic fields like the Aharonov–Bohm effect.

    It's not, I know its not, but without my glasses, I can no longer see the individual birds, only a cluster big enough to fire the nerve in my retina.

    That description would be apt, except for the fact that some interactions will then cause all of the birds at other locations to instantly disappear, or to change into other states. If readers are curious, they can look for much longer rebuttals of this in response to many of your other posts, but it makes it look like you've only read about quantum mechanics from news outlets, and not an actual text book or class notes.

    They can only be created and observed that way, so they must only exist that way.

    Oh, maybe your the same AC that has been saying photons can only be created or seen by discrete processes of changing electron levels in atoms. That is flat out wrong, as there are several processes the photons can be created or detected by, some of which are continuous (e.g. scattering and bremsstrahlung).

    I think the sun and planets go around the earth, I make an equation to explain the weird loop-the-loops that planets do.

    Of course you can make an equation with "loop-the-loops" or epicycles, but the only way to get it to match observations would be an infinite series that ends up matching the actual paths they make around the sun. Just like any function can be broken down into components by Fourier transform or many other transforms, whether or not it makes sense to a given situation, but you still make the same predictions in the end with the full series.

    But go ahead, keep reposting your BS, over the last couple years you've managed to get +5 before someone notices sometimes, or even get a few by without any replies if you post them to a story late enough.

  4. This gets modded +5? by Anonymous Coward · · Score: 3, Informative

    Yes, you remember the half of the story that most people forget, but that is useless without the whole story.

    The point of the Schrodiner's cat experiment was to be a reductio ad absurdum argument, except it turned out that quantum mechanics is quite absurd by comparison to most physics interacted with on a day-to-day basis. That doesn't mean the cat is not both dead and alive. It turns out that quantum mechanics does allow for macroscopic superposition of states that are suitably isolated

    So yes, the cat can be both dead and alive, as long as quantum mechanics is still believed to an accurate prediction of how things work.

  5. Re:Not Hard To Imagine by Roger+W+Moore · · Score: 3, Informative

    Science seems to blinkered in the belief that time has only one direction.

    Really? I'd suggest you try taking a Special Relativity course where you'll learn that relativistic effects are caused by the rotation of the space-time axes between inertial frames e.g. the reason for length contraction is because the object's time direction points partly along the observers length direction.

    There's some big thinkers out there who don't make this assumption of one-directional time in the electrical engineering discipline. In doing so, they can apply this thinking to electrons, which they've found can pop in and out of existence.

    Wow it's almost like they are physicists from ~60 or so years ago. I can only hope their knowledge of electronics is more up to date or do they still insist on using valves? We've known for a long time that electron-positron pairs can pop out of the vacuum. This gives rise to measurable effects such as vacuum polarization which changes the strength of the EM force with energy and Casimir effect. In fact Feynman actually showed that a positron (anti-electron) was equivalent to an electron with the direction of time reversed so you can indeed treat a virtual electron-positron loop as something oscillating back and forth in time.

  6. Re:Determinism is overrated by Anonymous Coward · · Score: 2, Informative

    What? The classical halting problem is based on a deterministic machine. For any given state, you can calculate the future state, at any specific time, by just running the machine it is built on. You might not be able to predict what the machine does in the infinite future, and you might not be able to determine what will happen with less complexity than just running the machine, but that doesn't contradict determinism. A deterministic universe doesn't require that someone from within be able to collect all of the necessary information and to perform enough computation to predict their experiment's future with certainty.