I Why is the minimum energy equal to the energy uncertainty?

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The discussion revolves around the relationship between minimum energy and energy uncertainty, specifically referencing a video that claims ΔE≥½hf implies E0=½hf. Participants clarify that the statement indicates the ground state energy E0 must be at least equal to hf/2, not that minimum energy equals energy uncertainty. The confusion stems from interpreting the implications of the energy uncertainty principle. Ultimately, the minimum energy is defined by the ground state energy, which is constrained by the uncertainty principle. Understanding this distinction is crucial for grasping quantum mechanics concepts.
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Why is the minimum energy equal to the energy uncertainty?
I was watching this video on Youtube, however, I don't get the step at 14:50 where he says that ΔE≥½hf means that E0=½hf.

Could someone explain why the minimum energy is equal to the energy uncertainty?

 
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"Watch this obviously confusing video and then explain it to me" is a big, big ask.
asdf said:
Could someone explain why the minimum energy is equal to the energy uncertainty?
It's not.
 
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Amended: "Watch this obviously confusing 37 minute video..."
 
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asdf said:
I don't get the step at 14:50 where he says that ΔE≥½hf means that E0=½hf.
It's just saying that, since the energy of any state whatever must be greater than or equal to ##hf / 2##, the energy of the lowest energy state, the ground state energy ##E_0##, is equal to ##hf / 2##.

asdf said:
Could someone explain why the minimum energy is equal to the energy uncertainty?
That's not what the above is saying.
 
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For the quantum state ##|l,m\rangle= |2,0\rangle## the z-component of angular momentum is zero and ##|L^2|=6 \hbar^2##. According to uncertainty it is impossible to determine the values of ##L_x, L_y, L_z## simultaneously. However, we know that ##L_x## and ## L_y##, like ##L_z##, get the values ##(-2,-1,0,1,2) \hbar##. In other words, for the state ##|2,0\rangle## we have ##\vec{L}=(L_x, L_y,0)## with ##L_x## and ## L_y## one of the values ##(-2,-1,0,1,2) \hbar##. But none of these...

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