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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.
...because this headline seems to have been cut sh
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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.
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.
If you accept this universe is simply mathematical function, weirdnes goes away. Function, that is itself probably intersection of multiple functions, some of them being evaluated backwards of what we percieve as "time", therefore creating weird effects in our perceived direction of time. Actually, laws of physics in not all that interesting to me (beyond some level), because physics is going after "particles" and "forces" that happen to be in this function, describing this universe. There is infinite number of other configuration. Function y = sin(x) exists just like our universe, so does set of integer numbers or PI.
If "universe" is locally predictable in one direction (which becomes "axis of time"), then self-replicating features (life) can emerge. In the case of our universe, there is atomic/molecular level complex and yet locally perfectly predictable, that enabled (under "perfect circumstances"?) life forms. atomic/molecular level isolates low level quantum weirdness. After all, life doesn't care if this function is predictable at ALL levels, molecular level is enough, and it happens to be good for many other reasons. There is so many random things needed for universe to sustain life, that probably insignificantly small portion of functions has any self-replicating (living) features, let alone intelligent.
Why should I be surprised by weirdness of quantum world then? It never needed to be predictable in our direction of time.
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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.
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.
Here is what is now thought when science is done. An observation is made. If we take Galileo as an example, he observed bones in animals. Then We make a mathematical model. In that case it was the relationship between mass the bone volume that was needed to support the mass. Then we make testable predictions based on that model, Galileo made the prediction that Giants do not exist, which is true, and could not have existed, which is one of the things that made the Church mad.
Relativity and Quantum mechanics both depend heavily on the mathematical model to make predictions on things that are not part of our everyday experience. This is different from classical physics where the mathematical models were based on things that most people observe. Classical physics is a ball falling and bouncing off the floor or light refracting through a prism. Quantum mechanics is a ball tunneling through the floor or light refracting around a galaxy. What I find interesting is that people take Relativity at face value and have a problem with Quantum Mechanics. It is true that we see a limit in velocity in the macroscopic world, but that has to do with friction, not relativity. There is nothing in our experience that says we cannot go as fast as we have the energy to accelerate. Certainly our mass does not increase if we are traveling at 80 miles and hour in a car instead of 30 miles an hour.
OTOH, our experience does tell us that second and third hand information is unreliable, and we are often better off making direct observations if possible. Are we just going to let some stranger bury our cat on the statement the cat fell off the roof and died? No, we want to see the cat, and until we do we hope the cat is alive, but there is chance the cat is dead. Is it both? No, it is uncertain, which is the key thing that people do not learn about science. Uncertainty.
In Quantum Mechanics this is called a wave function, and the cat is in a superposition of wave functions that represent all possible states. The wave function collapses when we make an observation.
Here is another interesting thing. Quantum Mechanics came about to a problem with infinity. Relativity never solved it's problem with infinity, at least not completely, and when combined with Quantum Mechanics develops more infinities. This is what does not make sense.
"She's a scientist and a lesbian. She's not going to let it slide." Orphan Black
1. if detecting a particle *determines* its state vs *observes* it state, (the main point of conflict) then:
2. There is no perfect isolation, a vacuum is not perfect, and does not shield magnetic fields or other effects.
3. Interactions with other stuff *IS* detection. That other stuff does get influenced depending on the state of the particle. The magnetic field does influence the world around it.
4. Your photon has a magnetic field, and that influences the matter around it, depending on its wave function.
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.
6. Thus your Quantum uncertainty theory can never work, the particle/photon/whatever's state MUST be determined BEFORE *you* detect it by its interactions with other matter.
Interesting argument, but I'm not sure that I agree on point 3. We've got a number of very subtle experiments that have tried to tease out exactly where the observer effect starts and ends. Bell's Theorem and EPR prove that no hidden variables exist, so these properties are not things that are stored and just discovered when we check - the behavior that's observed can only be explained if they "decide" what to be when we make a measurement.
Also, consider things like the quantum eraser, and delayed-choice quantum eraser - it seems like the universe is keeping track of what we are looking for and how, such that we can "detect" a particle, destroying the wave-nature and interference pattern, but then "erase" our knowledge of the detection, and see the wave-nature restored.
Finally, with your point about the bricks, you seem to be saying that maybe half-particles exist but we can't detect them because of limitations of our instruments - but discrete, quantum-mechanical behavior extends to far more than just particle counts and even positions. The Stern-Gerlach apparatus being a clear counterexample to your point. The behavior observed there doesn't depend on dealing with any particular number of particles - it just shows that particle spin is entirely quantized, since the particles passing through are deflected entirely one direction or another. We could readily detect particles which were deflected partially, according to continuous, classical behavior - if they existed.
Ultimately, you've got a good argument if all your suppositions are true, but we've got experiments that prove quantum uncertainty as well as anything has ever been proven. In the words of Feynman: "It doesn't matter how beautiful your theory is, it doesn't matter how smart you are. If it doesn't agree with experiment, it's wrong."