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HNQ
5:40 AM
2
Q: Is this measure employed in the Faddeev-Popov procedure related to the Haar measure?

user1620696In the Faddeev-Popov procedure one defines the Faddeev-Popov determinant through the formula $$\int {\mathcal{D}\alpha \ } \delta\big[G(A^\alpha)\big]\Delta[A]=1,\tag{1}$$ where $G(A^\alpha)$ is the gauge-fixing condition and $A^\alpha$ is the gauge field $A$ transformed by a finite gauge transfo...

 
 
8 hours later…
HNQ
1:57 PM
3
Q: Commutator and Taylor series in quantum mechanics

tinghaoliuI have learned about the commutators, and read this: $$[A, f(B)] = f'[A,B]+\frac{1}{2}f''([A,B]B+B[A,B])+\frac{1}{3!}f'''([A,B]B^2+B[A,B]+B^2[A,B])+...$$ then Simplified to $$[A, f(B)] = [A,B](f'+f''B+\frac{1}{2}f'''B^2+...)=[A,B]\frac{df}{dB}$$ I do understand the first two equations, only don't...

 
 
3 hours later…
HNQ
4:51 PM
2
Q: How to transform these coordinates by substitution in classical mechanics?

NirvanicUniverseThe goal is to transform the following coordinates: $$x(t)= R(\Phi-\sin\Phi)$$ and $$z(t)=R(2 +\cos\Phi)$$ with the substitution: $u=\cos\left(\Phi/2\right)$ in order to get: $$x(t)=2R(\arccos(u)-u\sqrt{1-u^2})$$ and $$z(t)=R(1+2u^2)$$ How do I go about solving this problem? I already tried using...

 
HNQ
5:16 PM
6
Q: Why do the steel balls climb up?

Shibu NagendranI made a classical experiment to demonstrate centrifugal force. The experimental setup is made to stand vertically and spun along the vertical axis. The balls that initially rest at the bottom, on spinning, move up to the chamber. Can someone please explain in layman terms as to why this happens?...

 

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