Does the uncertainty principle break symmetry?

kahoomann
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The classic physics problem example of symmetry breaking is a pencil sitting directly on its tip (pointed down), but it's possible for the pencil to balance on its tip if we reduce the thermal
fluctuations to zero by cooling it to close zero degree.
Quantum fluctuations require/mean that after some time no matter that it was ‘perfectly’ balanced it is going to fall over. So the question is that would the pencil, a classical object, fall over due to quantum fluctuations in a thought experiment pioneered by Einstein?
 
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If by "HUP" you also includes quantum fluctuation, then of course it can induce some symmetry breaking. Isn't that the whole principle behind quantum phase transition? But this isn't an identical scenario with a pencil sitting on its tip. Besides the realistic problem of setting up the experiment, one should also consider that if the effect is THAT pronounced as to tip over a pencil, then it should also manifest itself in other experiments that are even more sensitive, such as the nanoscale balance that was reported a while back, and all those sub-micron gravitational measurement that came out of the University of Washington. Yet, unless I missed something, they detected no such effects.

Zz.
 
The tip of the pencil - even though appearing very sharp to you - is still orders of magnitude wider than necessary to overcome quantum fluctuations. They are extremely small.
 
peter0302 said:
The tip of the pencil - even though appearing very sharp to you - is still orders of magnitude wider than necessary to overcome quantum fluctuations. They are extremely small.

I don't think the quantum fluctuations are constant in time. Once in a while, there will be a big fluctuation cause the pencil to fall
 
kahoomann said:
I don't think the quantum fluctuations are constant in time. Once in a while, there will be a big fluctuation cause the pencil to fall

Then you need to show experimental evidence of the presence of this "big fluctuation", and why it is not detected in all the other, more sensitive, experiments. Without such evidence, you are making unfounded speculation.

Zz.
 
Yes, and once in awhile all the atoms in the pencil will randomly decide to move upward and the pencil will levitate.

Except for the fact that the odds are one in a number with a whole lot more zeroes than you'll see in the lifetime of the universe.
 
Insights auto threads is broken atm, so I'm manually creating these for new Insight articles. Towards the end of the first lecture for the Qiskit Global Summer School 2025, Foundations of Quantum Mechanics, Olivia Lanes (Global Lead, Content and Education IBM) stated... Source: https://www.physicsforums.com/insights/quantum-entanglement-is-a-kinematic-fact-not-a-dynamical-effect/ by @RUTA
If we release an electron around a positively charged sphere, the initial state of electron is a linear combination of Hydrogen-like states. According to quantum mechanics, evolution of time would not change this initial state because the potential is time independent. However, classically we expect the electron to collide with the sphere. So, it seems that the quantum and classics predict different behaviours!
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