Are Lie Brackets and Their Derivatives Equivalent in Vector Field Calculations?

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The discussion addresses the equivalence of Lie brackets and their derivatives in vector field calculations. The first question involves proving the relationship between the Lie derivatives, specifically \mathcal{L}_{u}\mathcal{L}_{v}W - \mathcal{L}_{v}\mathcal{L}_{u}W = \mathcal{L}_{[u,v]} and whether the simplification leads to the correct expression. The second question focuses on calculating the Lie bracket [X,Y] for given vector fields X and Y, and whether a specific expression is equivalent to this calculation. The participant ultimately resolves their confusion regarding the vector field W in the first question and acknowledges missing it in their initial analysis. The discussion highlights the complexities of Lie derivatives and brackets in vector field theory.
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Hi i have two questions:
1) When asked to prove \mathcal{L}_{u}\mathcal{L}_{v}W - \mathcal{L}_{v}\mathcal{L}_{u}W = \mathcal{L}_{[u,v]}.

I achieved [u,v]w = \mathcal{L}_{[u,v]}. This was found by appliying a scalar field <b> to the LHS and simplifying and expanding using + and scalar linearitys to get [u,v]w but I am not sure if these are equivalent.

2) When asked to calculate the Lie bracket [X,Y] where X=5x^{2}\frac{\partial}{\partial t}-4t\frac{\partial}{\partial x} and Y= y\frac{\partial}{\partial t} + t\frac{\partial}{\partial y} is this equivalent to:
\left((5x^{2}\frac{\partial}{\partial t} -4t\frac{\partial}{\partial x})\frac{\partial (y\frac{\partial}{\partial t} + t\frac{\partial}{\partial y})}{\partial x^{a}}-(y\frac{\partial}{\partial t} + t\frac{\partial}{\partial y})\frac{\partial (5x^{2}\frac{\partial}{\partial t}-4t\frac{\partial}{\partial x})}{\partial x}\right)\frac{\partial}{\partial x^{b}}

and if so can it be expanded any further I am not so sure but i don't fully understand \frac{\partial}{\partial x^{a}} derivatives.
 
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never mind figured it out
 
I'm sure you're missing out the vector field W in the RHS of 1).
 
yeah i figured them out and yeah missed it off, thx
 

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