Question about QM. Cat in the box.

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Do you believe in Quantum Mechanics as a hard science?

Yes
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No
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29%
 
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Borommakot
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Question about QM. Cat in the box.

Post by Borommakot »

I heard this somewhere.


An event doesnt actually happen until we observe it.

Somebody told me this theory of QM and it could be bs or not.

If one were to put an isotope with a 50% chance of decaying(iffy science, but that part is'nt very important)in a box, along with a sensor that, if the isotope decays, the sensor releases a poison gas into the box. If we put a cat in the box and close it up, that cat could die, or maybe it wouldn't. But we wouldn't know. My scientist friend said that the cat is "neither alive nor dead, until the box is opened and we observe the cat.

So basically, if a tree falls in a forest with no one around to hear it, does it still make sound?

Is this true? Does QM think like this?
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DHodges
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Post by DHodges »

Your friend was referring to the Schrödinger's cat thought experiment. There are different interpretations as to what it means.
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Ryan Rudolph
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Post by Ryan Rudolph »

To Borommakot,
My scientist friend said that the cat is "neither alive nor dead, until the box is opened and we observe the cat.
Here is my take. So because the box is closed, and there is a 50/50 chance that the cat is either dead or alive, outsiders cannot be absolutely certain what the status of the cat is until they open the box, but the way I see it is that there is a truth of the matter as to whether or not the cat is in fact alive or dead even if the outsiders are not directly aware of it at the time.
Is this true? Does QM think like this?
The problem with QM is that their instruments cannot understand the processes happening at the micro-level of atomic organization that they delve into.

In the outward world, we can observe predicable laws and patterns such as causality, duality and so on, so there is a sense of order.

However, when quantum scientists start trying to probe around with their limited instruments into an infinite plane of micro-atomic activity, there calculations never seem to quite match up with what is happening. They face a world of deterministic unpredictability, a paradox. Guys like Einstein and Bohr drove themselves nuts trying to get around the nonsensical nature of the quantum world, and this is why Einstein rejected many of Bohm’s ideas because they contradicted many of his classical ideas like deterministic locality.

Bohm introduced the hidden variables theory and the idea of nonlocality, which blew classical QM right out of the water. The mathematical number crunchers despised Bohm because he was questioning the very foundation that allowed them to blindly perform calculations all day long, and get paid loads of money to do it.

Quantum physicists typically try to get around the dissonance between their calculations and their theories by making all sorts of bizarre assumptions about the quantum world, but Bohm constantly questioned these assumptions.

David Bohm was one of the few Quantum Physicists that truly understood their folly, and he was ostracized from much of the QM community because of his relentless questioning and penetration. Moreover, he had seen that his fellow scientists were more concerned with welding complicated formulas and mathematics then actually trying to understand what is happening by observing micro-atomic relationships.

In the end, Bohm’s hidden variable theory lead to him to develop the idea of an infinite level of organization where this reality is connected to an infinite number of deeper realities, and all realities relate and connect to each other simultaneously and nonlocally.

Bohm stressed that a scientist should allow his imagination to be primary as a means to visualize things, which develops over time based on his observations. Bohm suggested that a scientist should always add to what he already suspects is true by observing and thinking about what doesn’t seem quite right. Moreover mathematics to Bohm was just a necessary evil. Although he was a strong mathematics student, he was more concerned with developing his ideas than devoting all his energy into mathematical proofs. Many times, he had his students correct the mistakes in his mathematical proofs because he couldn’t be bothered to do it himself.
Last edited by Ryan Rudolph on Fri Feb 23, 2007 1:40 am, edited 1 time in total.
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Cory Duchesne
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Post by Cory Duchesne »

This article may be of interest to some.
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Post by excelsior »

I am preparing to become a computer engineer and in my studies I have made some progress in understanding QM. It is a strongly founded science that basically says that energy is quantified (as in particle's level of energy, waves' energy etc). A lot of philosophical questions were drawn from its misunderstood experiments. Let's take Heisenberg principle, for example. It says that the more acurate we measure a particle's speed, the less we know about it's position. Therefor, the scientist influences the experiment. The philosophical conclusion was that Laplace hypothesis( that if we know all particles' exact positions and velocities at a certain moment we can predict both past and future) is invalid. Actually Heisenberg's principle is based on the fact that in order to observe a particle(electron) you emit photons(light components) to it therefor influencing the observed object's parameters.
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Ryan Rudolph
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Post by Ryan Rudolph »

Here is a video of Bohm in his older years, although he is a man I have great respect for, he still had a level of delusion. If you listen to what he is proposing carefully, he's calling for his quantum theory of wholeness to help people out of their fragmented delusions.

He blames much of humanities delusion on their mechanistic view of reality, so he calls for his theory of wholeness as a solution.

This was a huge source of conflict for Bohm and Jiddu Krishnamurti. Although K acknowledged the usefulness of theories in science to aid in technological progress and so on, he didn’t see their practicality in helping humanity out of delusion, and this is why his entire teaching is psychology-based.

In Bohm’s biography it suggests that in the early years, Krishnamurti admits to having dialogues with Bohm that were more intense and exploratory than anything he experienced with anyone else, and he admits that Bohm aided him in the refinement his own teachings because of how relentlessly inquisitive Bohm was.

But near the end of their lives, K was frustrated at Bohm’s inability to give up the worth of his theory, and the potential it had to help humanity. K continued to be harder and harder on Bohm as the years went on, but his efforts had no affect. Finally he annouced publicly in front of many of their closest friends that Bohm hasn’t gone through the transformation all at, and that if Bohm couldn’t change, what hope had anybody else had!

This sent Bohm into a severe depression, and he never actually recovered from it, he kept going into relapses right up into his later years before his death. K knew how weak Bohm had become so he ceased contact completely, and they never explored to that same intensity ever again.

Another problem with Bohm is that his mother has suffered from severe manic depression, and Bohm had inherited that genetic link, so he didn’t have a chance.

However, for the extent of Bohm’s imperfections, he did well, and even though he knew how thought deceives, he couldn’t pull himself out of many of his delusions.
Last edited by Ryan Rudolph on Fri Feb 23, 2007 3:24 am, edited 1 time in total.
Elizabeth Isabelle
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Post by Elizabeth Isabelle »

Ryan Rudolph wrote:To Borommakot,
My scientist friend said that the cat is "neither alive nor dead, until the box is opened and we observe the cat.
Here is my take. So because the box is closed, and there is a 50/50 chance that the cat is either dead or alive, outsiders cannot be absolutely certain what the status of the cat is until they open the box, but the way I see it is that there is a truth of the matter as to whether or not the cat is in fact alive or dead even if the outsiders are not directly aware of it at the time.
I agree. If the cat is not breathing, its heart is not beating, and it is cold (as defined by its objective body temperature beingcloser to ambient temperature rather than living cat temperature) and stiff, it is dead whether anyone outside the box is aware of this or not.

Your scientist friend may be playing with definitions of "officially" dead or alive. In a hospital, a patient is not dead until a doctor says so. In forensics, a death can be retroactivly declared and is often done so to estimate a time of murder. If someone stuffs a person into a trash compactor usually only used for cardboard boxes, turns it on and walks away, death would be said to have occurred at that time - not three days later when the cops open the compactor at the employment building of the missing person in response to complaints of a bad smell.
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Cory Duchesne
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Post by Cory Duchesne »

Ryan Rudolph wrote: But near the end of their lives, K was frustrated at Bohm’s inability to give up the worth of his theory, and the potential it had to help humanity. K continued to be harder and harder on Bohm as the years went on, but his efforts had no affect. Finally he annouced publicly in front of many of their closest friends that Bohm hasn’t gone through the transformation all at, and that if Bohm couldn’t change, what hope had anybody else had!
It sounds like you still think pretty highly of JK.

As for his utterances on his death bed, don't you think that was just the vanity of his own fanciful theories refusing to admit defeat?
He blames much of humanities delusion on their mechanistic view of reality, so he calls for his theory of wholeness as a solution.
I think the problem is mecahanistic outlooks existing in the same mind that also has superstitious outlooks. Not to mention the minds entrenchment in sensuality.

Mechanistic knowledge, superstition, and sensuality - a recipe for disaster.
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Ryan Rudolph
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Post by Ryan Rudolph »

Cory wrote:
As for his utterances on his death bed, don't you think that was just the vanity of his own fanciful theories refusing to admit defeat?
I agree, Both men had their imperfections although one’s deathbed utterances are usually quite feeble, which can be observed by referring to many different thinkers. I’ll probably utter something along the lines of “OH GOD, MOMMA NO, DON’T TAKE ME YET!!”

Seriously though, In regards to Bohm and K, no human has ever been the pure absolute truth, it is impossibility, but thinkers have been close to it, and based on the evidence, I would say K was closer than Bohm, although each had many flaws.

I suspect that K did experience the depths of emptiness, but the mystical experiences probably did him in, he probably intrepreted them in a way to give himself a sense of cosmic significance and importance. K's weakness was his ego.
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Post by Borommakot »

[excelsior said:]It says that the more acurate we measure a particle's speed, the less we know about it's position. Therefor, the scientist influences the experiment.[/quote]

From the little I know about science, I have a problem with this theory. It takes a quantum of energy to move one electron to the next highest energy level, correct? Say we wanted to measure the position and speed of an electron. We would shoot a quantum of energy at the different spots the electron might be, until we hit it. Then we would know where that electron was, if we repeated that expirement multiple times and identified a time-based pattern, such as:every one nano-second, the electron is exactly HERE. My science is iffy there but you get the picture. That would give us the amount of time it takes for the electron to go all the way around the atom which, compared to the size of the atom, would give us the speed. We could at least find out wether or not the speed is constant around an atom with that method. I'm pretty sure I'm missing something, but as I said before, I have a small knowledge base in science.
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Post by excelsior »

Borommakot,
the electron is exactly HERE.
There are several problems with this affirmation. I suggest you should start with this in order to understand what I was saying:
http://en.wikipedia.org/wiki/Uncertainty_Principle
If you are really interested in QM as a science, not as philosophical speculations, you may private me if you have questions or need better resources for studying it.

As for the others that were talking about Schroedinger's Cat experiment, the interpretation you give for the scientific conclusion is wrong because you actually do not understand it, you treat it as philosophical affirmation that needs to be commented upon. I think you should take it stricto senso: It only means what it says, nothing more, nothing less.
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Post by Tharan »

Here is my take on Schrodinger's Cat: The universe on the scale of a cat would not be affected by the dancing of a single photon or quanta. An elaborate chain of events (a device) linking the two would be equally subject to interference from it's own structure and outside its own structure as it would the dancing states of the target particle. And there would be no way to tell that the particle in question was the actual object that triggered the linking device to kill the cat. Heisenberg made sure of that.
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Post by plotinus »

In the Schrödinger Cat Experiment, in order to prevent the wave function from collapsing, the interior of the box must be completely sealed off from all outside influences. The one influence which cannot be blocked is gravitational influence. Gravity would cause the collapse of the wave function almost instantaneously.

It is extremely difficult to prepare a group even of a few atoms so that they will be in a mixed state for a short time. As the system to be prepared grows more complex, the difficulties mount exponentially.

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Last edited by plotinus on Sat Mar 10, 2007 2:38 pm, edited 2 times in total.
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Post by Kevin Solway »

plotinus wrote:The one influence which cannot be blocked is gravitational influence.
Actually, there are countless things that can't be blocked out. I don't think things like temperature changes could be blocked out entirely, and certainly not nuclear explosions, or people who have the means to get into the box.
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Post by Shahrazad »

Gravity would cause the collapse of the wave function almost instantaneously.
I disagree, because gravity is not an observer and is not conscious.

Consciousness is what causes the collapse of the wave function.

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Post by Diebert van Rhijn »

Shahrazad wrote: Consciousness is what causes the collapse of the wave function.
And why wouldn't the collapse been able to cause the consciousness?

One just ends up "mathematically confirming the syntax of ones mother tongue". In other words: the answer is already confined by the questions asked. This is the more universal principle and shows just the limit of empiricism, while it doesn't reveal terribly much about consciousness or the sub-particle's foundations for that matter.

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Diebert van Rhijn
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Post by Diebert van Rhijn »

Sharazad wrote: Consciousness is what causes the collapse of the wave function.
Diebert van Rhijn wrote: And why wouldn't the collapse been able to cause the consciousness?
Only after I wrote my question I remembered that some research is actually claiming that: quantum wave function "self-collapse" possibly essential for consciousness, and occur in cytoskeletal microtubules and other structures within each of the brain's neurons.

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Shahrazad
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Post by Shahrazad »

This is the more universal principle and shows just the limit of empiricism, while it doesn't reveal terribly much about consciousness or the sub-particle's foundations for that matter.
Well, obviously consciousness is still a big mystery to us, particularly the hard problem.
Only after I wrote my question I remembered that some research is actually claiming that: quantum wave function "self-collapse" possibly essential for consciousness, and occur in cytoskeletal microtubules and other structures within each of the brain's neurons.
Yeah, pretty neat stuff.

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