I have to tell you, there is one aspect of quantum physics I just don’t get. I think it is best summed up in the story of Schroedinger’s cat. That things don’t exist unless I ‘measure’ them (?).
I mean, I leave a room. And when I come back, everything is where I left it. I find it very hard to believe things don’t exist unless I perceive them. Actually, it sounds a little bit like the story of Santa Claus, no? Though I am sure that is just a coincidence. In any event, I am not a scientist. So I would not be the best judge of these things.
One thing that puzzles me, though, if this is true. What happens when I sleep? I am not actively perceiving things in my room as I am sleeping. So does the same rule apply? Think about it. Because if the same rule applies, it would be rather silly, like the story of Shroedinger’s cat is intended to be. Am I wrong?
The Shroedinger’s Cat thought experiment is meant to highlight a conundrum in quantum physics (or rather, our understanding of reality given the truth of quantum physics). Namely that it makes no sense that we know of to insist that something as massive as a cat can be in a superposition of two exclusive states, alive vs. dead. The question is where do the boundaries apply between classical and quantum views of reality.
Physicists do not insist that a “measurement” requires a living conscious observer. The scientific community is still struggling to define just what does make the difference but it’s currently thought to be a quantum state passing some threshold of interaction with its environment.
The point of Schrodinger’s Cat is to emphasize that, in Quantum Physics, ALL possibilities exist until a choice/action is actually made. The fact that you are asleep is irrelevant. Granted, his brilliant equation can calculate the probability of an occurrence, but that doesn’t change the fact that ALL possibilities exist until an occurrence.
I don’t know if someone like Chronos has linked this Saturday Morning Breakfast Cereal comic yet, but it’s a really elegant and funny explanation for layfolk (like me) of what’s meant by quantum superposition and probability in the quantum realm in general.
I didn’t know what I didn’t know about quantum superpositions until my second semester of P. Chem, with the Schrödinger Wave Equation for the Hydrogen Atom. In short, trust the math, not your intuition.
My understanding of Quantum Mechanics and Philosophy is rudimentary, so my observations here maybe totally out of whack. I
Western thought processes are heavily influenced by Plato and Aristotle who put down the foundations of western logic. It is baked into language, reasoning and even beliefs and kids learn it very early in life. And there is this concept of absolute or objective truth/reality that is observer independent. So Quantum Mechanics, which weaves the observer to the observation becomes somewhat confusing.
Eastern (Indian to be specific) thought processes acknowledges the observer as integral to reality and emphasizes the existence of “many” truths. So Quantum mechanics “feels” intuitive and jives with the concept of observer created reality.
As an illustration, most Europeans find the joke “When a tree falls in the forest …” to be funny or a logical contradiction of sorts. Most Indian guys just don’t get the joke.
I think the logic extends to religion as well where the existence of One God proves the falseness of all other Gods.
Not saying that the Eastern Philosophers had QM in mind or were more advanced, just that the thought process helps with understanding QM.
This is one of the grand questions in Physics. Quantum Mechanics clearly works at the atomic level. It doesn’t seem to apply at the cat level. Which is one of the major points of Schrödinger’s thought experiment. (It’s pointing out a problem with some QM models. Not establishing a fact.)
There’s a lot of stuff that happens at the atomic level that doesn’t happen at our level. E.g., everything is reversible atomically. If an event can happen, the reverse can happen. Easily. Basically automatically. But try putting a burned newspaper back together, never mind waiting around for it to restore itself on its own.
There’s “safety” in numbers here. Things are very probabilistic at the quantum level. A zillion events with even decent odds of happening aren’t all go to happen, esp. with a required time frame. Hence “something” happens incredibly rapidly right away to the cat and the matter is settled.
This is one of the issues with quantum computers. They have to kept in just the right state long enough for the computation to complete. This is really, really hard. And this is for a few dozen qubits. Scaling up to more qubits and for longer periods of time is a incredibly hard job.
A room just isn’t up to it by a phenomenally large order of magnitude. Nor is a cat.
Quantum mechanics does work at the cat level. It’s just that, if you take the laws of quantum mechanics and apply them to a cat, you get results very close to identical to what you’d get from applying classical laws the the cat.
I hadn’t actually seen that SMBC link before, but it’s spot-on.
And that post by am77494 is exactly the sort of thing that the SMBC link is trying to combat. Quantum mechanics is no more like “Eastern thought processes” than it is Aristotelian. Just because both are weird and hard to understand doesn’t mean they’re both the same thing.
Totally agree. Also agree with Feynman who said "“If you think you understand quantum mechanics, you don’t understand quantum mechanics.”
Allow me to illustrate what I was saying earlier :
Say there is this statement : *S = An electron is a particle. *The greek system of logic, inherent in the western thought process, makes you either prove it right or wrong.
The Eastern logic process, also inherent in the eastern thought process, makes you consider 4 options at the minimum (Cite)
1> S is true
2> Not that S is true
3> S is true and not true
4> Not that (S is true and not true)
So when I took my QM 101 in college, and learnt about an electron having both the properties of a wave and a particle, the concept did not sound non-intuitive to me. Similarly when we solved the position wave function for a particle in a 1-D box, it was intuitive that the wave extended outside the box (quantum tunneling).
Again the point I am making is not that QM is like “Eastern Thought” but that eastern thought makes understanding QM easier at least at the 101 level.
Also a class I took on innovation remarked that the Greek system of logic is not very useful in the fields of “creative thinking” or “parallel thinking”. It is explained in detail here : Parallel Thinking – De Bono Group
Schrödinger’s cat is an example of a problem raised by the Copenhagen interpretation of quantum mechanics. The Copenhagen interpretation is the most widely used, but there are serious problems with it that have never been resolved.
However, there are many alternative interpretations of quantum mechanics, and no consensus among physicists about them, despite many decades of intense debate.
For a good book about this, see What is Real? The Unfinished Quest for the Meaning of Quantum Physics by Adam Becker
Things exist without you measuring them, and have whatever state they have independently of you measuring them. But on one hand you don’t know what state they have until you do measure them, and on the other your measuring can change the state so that the state you measure is correct at the time of measuring but it’s not the same that the system was in before you measured. Quantum physics is probabilistic but not solipsistic.
The second part happens also in classical physics when you have a situation that’s barely stable. Think of a ball balanced atop a point: the ball is stable and has whatever size it does, but as soon as you try to use a contact method to measure that size it’s gonna fall off.
You’re using “Eastern thought” to mean “am77494’s mind”. You also previously made the assumption that every Westerner has the same sense of humor and that the joke about the tree falling in the forest makes sense in every Western language. Please don’t, either one.
The question of whether a tree falling in forest makes a sound if there is nobody to hear it, is NOT a joke, and the language doesn’t matter.
It’s a serious philosophical question posed by George Berkeley in the 18th century, as to whether perceptions exist outside the consciousness of the perceiver. He put forward the theory of ‘subjective idealism’.
Berkeley originally wrote in his Treatise Concerning the Principles of Human Knowledge (1710):
Any boundary is arbitrary. The wave function of the universe behaves presumably in accordance with the ‘laws’ of quantum mechanics. There can be no purely classical subset of any part of the universe, it is a calculating convenience, if not a philosophy.
Eastern philosophy might have some connection to how mind and consciousness work. But that’s not something it has in common with quantum mechanics, because quantum mechanics has no connection whatsoever to mind or consciousness.
And it’s not at all difficult to assign a single unambiguous true-or-false value to the statement “an electron is a particle”, provided that you’ve defined the term “particle”. If you’ve defined “particle” to mean “things like electrons”, then it’s clearly, unambiguously 100% true. If you’ve defined “particle” to mean “thing that acts classically”, then it’s clearly, unambiguously 100% false. And if you haven’t yet defined the word “particle”, then why are you even asking the question?
It does in some interpretations of QM. The Copenhagen interpretation, which is the only one most people know, says that an ‘observer’ causes the collapse of the wave function. So how do you define ‘observer’? Some say this does not imply a conscious observer, some say it does.
One step further is the ‘consciousness causes collapse’ interpretation accepted by von Neumann and Wigner. Also relevant here is the Wigner’s friend extension to the Schrödinger’s cat paradox.
Eugene Wigner, who was one of the greatest physicists of the 20th century, a Nobel Prize winner, and one of the chief formulators of quantum mechanics, said “It is not possible to formulate the laws of quantum mechanics in a fully consistent way without reference to consciousness.”
Yes, those who know how the Copenhagen interpretation works say it does not imply a conscious observer, and those who do not know how the Copenhagen interpretation say that it does.
In fact, it is not possible to formulate the laws of quantum mechanics in a fully consistent way with reference to consciousness.
Chronos - I am not a QM or Philosophy expert, and this is meant as an observation / discussion.
See when you say “an electron ***is a ***particle”, that “is a” part comes with the western philosophical understanding that it is the fundamental nature of the electron and it always was so and will continue to be so.
For example if I look in a box and say : “There is an electron in that box”, its a common Western philosophy inference that the electron was there the moment before I looked. Which we know is not true from the QM perspective.
There are still serious problems with the Copenhagen interpretation, and different ways of viewing it. There is certainly no consensus among physicists on how to interpret it, or even whether Copenhagen is the best interpretation to start with.
