Why is Quantum thoery so confusing that no body actually understand it ?

[glengarry]

but if everytime we do a measurement/observation we get an accurate result that exactly conforms to the calculations

The formalism of QM says precisely nothing about any given experiment that is performed once. It is only when a given experiment is performed an infinite number of times that the quantum mechanical "prediction" is said to have been finally realized.

This also means that if a given experiment is performed any finite number of times (no matter how large this number is), then there is not any kind of purely "quantum theoretical" statement that can be made about it.

It is for the reason that infinite experimental trials must be performed within the formal theory of QM that it can never, strictly speaking, have any kind of applicability to the universe of "real world" experimentation.

 

[GeorgCantor]

That...sounds like a prejudice.

Only up to a point. I believe that qm, qft and GR are describing reality as it is, i.e. they are a truer description of reality than our gross sensory inputs are leading us to believe. Those 3 theories are almost forcing us to reconsider the meaning attached to the word "universe" and possibly replace it with "reality". But you are free to label this assumption of mine a 'predjudice'. It seems modern physics isn't describing a universe but a reality that seems to look like a 'dance' of energy to the tune of the laws of physics. What we uncomfortably choose to label 'Particles' in my view, are simply blobs of energy that have acquired the ability to gain mass(rest or relativistic). Everything we interact with is based on an exchange of energy through electromagnetic repulsion. Assuming that everything may essentially be a form of energy, i see no contradictions with beginnings, zeno-like paradoxes, epr's, length contractions, time delations, singularities, quantum tunnelings, etc. There is no good definition nor good understanding of what energy really is, and yet the glimpses we were able to take at reality through quantum physics, are in my opinion incredible. I think we are fooled to believe in a fixed inmutable universe of objects in space and time by our place in it and how we are structured. It is modern physics that is giving us the opportunity to reach for some underlying truths, though not everybody may like them. Yes, it is assumption and to a point predjuice, but at least it's the most convincing one there is, imo. While science may or may not be a good tool to understand reality as it is, IMO it has more merit than all other approaches taken together.

A lot of people think it would be a complete waste of time to study the consequences of the assumption that QM describes reality, since it doesn't change the predictions of the theory. I think they're a little naive. Even if the assumption is wrong, we could learn a new way to think about QM that might even turn out to be useful when doing calculations.

Yes and this new way to think about QM might be based around the idea that reality simply isn't quite the way it seems. It's a good starting point for making progress on the foundational issues in physics and seems to come down to the old question - What is matter really?

 

[glengarry]

Yes and this new way to think about QM might be based around the idea that reality simply isn't quite the way it seems.

The idea that reality isn't constituted by its phenomenal manifestations is far from a new idea. That is, it didn't take a bunch of white guys in 1920's continental Europe to come to the realization that any fundamental description of nature must necessarily be something other than the way that our eyes (or any other sense organ) apprehends it.

It's a good starting point for making progress on the foundational issues in physics and seems to come down to the old question - What is matter really?

Well, I started this thread quite a while ago in order to do my best to describe a mathematical "picture" that I think can go a long way towards answering this question. I'm just waiting for someone else to show interest in my ideas before I post again to that thread.

 

[xcvxcvvc]

I don't know anything about quantum theory, but i liked that youtube video. Could someone tell me if the "no one knows what is going on and it seems impossible" conclusion at the end of this video is correct?

 

[GeorgCantor]

I don't know anything about quantum theory, but i liked that youtube video. Could someone tell me if the "no one knows what is going on and it seems impossible" conclusion at the end of this video is correct?

I don't think many would agree that an observer collapses the wavefunction(i.e. we are creating our own reality), but there is something weird and subtle about this experiment. The Delayed Choice Experiment(and the one with the eraser and un-collapse) and the double slit(and the one done with fullerene molecules) all seem to suggest that quantum 'particles' act in a way to preserve conjugate variables. Essentially this is saying that the observed particles are 'hiding'(masking) the information that we are trying to extract, so as to not violate the uncertainty principle. This is a very weird conclusion and one that is not easy to come to grips with, as it seems to suggest that the observer's knowledge of the quantum system can affect how the system behaves. I agree with the statement from the video that "the particles act as if they were aware that they were being watched". And if our knowledge or even the prospect of knowing, can somehow affect assumed outside real-world quantum systems, this can have profound implications for the role we have in reality.

It gets more interesting when you ask 2 questions:

1. What is knowledge and is it such an essential ingredient of reality?

2. Is the observer really separate from the system being measured?