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Qmechanic
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Suppose we have a vector $A^\mu$. This vector has 4 components (0 through 3). If we consider the Lorentz's transformation of each component, we could simplify them into matrix notation, ${A^\prime}^\mu=L^\mu_{\nu} A^\nu$${A^\prime}^\mu=L^\mu{}_{\nu} A^\nu$, where:

$$L_{\nu}^\mu= \left( \begin {matrix}\gamma & -v\gamma & 0 & 0\\ -v\gamma & \gamma & 0 & 0\\ 0&0&1&0\\ 0&0&0&1\\ \end{matrix}\right)$$$$L^\mu{}_{\nu}= \left( \begin {matrix}\gamma & -v\gamma & 0 & 0\\ -v\gamma & \gamma & 0 & 0\\ 0&0&1&0\\ 0&0&0&1\\ \end{matrix}\right)$$

where $\gamma=(1-\frac{v^2}{c^2})^{-\frac{1}{2}}$

Knowing that $A_{\mu}= \eta_{\mu\nu} A^\nu$ and

$$\eta_{\mu\nu}= \left( \begin{matrix} -1&0&0&0\\ 0&1&0&0\\ 0&0&1&0\\ 0&0&0&1\\ \end{matrix}\right)$$

we could say that $A_\mu^\prime= M_{\mu}^\nu A_{\nu}$. According to my calculations:

$$M_{\mu}^\nu= \left( \begin{matrix} -\gamma&v\gamma&0&0\\ v\gamma&\gamma&0&0\\ 0&0&1&0\\ 0&0&0&1\\ \end{matrix}\right)$$

But according to Leonard Susskind's lectures: $M=\eta L\eta$

which doesn't agree with my calculations.

Suppose we have a vector $A^\mu$. This vector has 4 components (0 through 3). If we consider the Lorentz's transformation of each component, we could simplify them into matrix notation, ${A^\prime}^\mu=L^\mu_{\nu} A^\nu$, where:

$$L_{\nu}^\mu= \left( \begin {matrix}\gamma & -v\gamma & 0 & 0\\ -v\gamma & \gamma & 0 & 0\\ 0&0&1&0\\ 0&0&0&1\\ \end{matrix}\right)$$

where $\gamma=(1-\frac{v^2}{c^2})^{-\frac{1}{2}}$

Knowing that $A_{\mu}= \eta_{\mu\nu} A^\nu$ and

$$\eta_{\mu\nu}= \left( \begin{matrix} -1&0&0&0\\ 0&1&0&0\\ 0&0&1&0\\ 0&0&0&1\\ \end{matrix}\right)$$

we could say that $A_\mu^\prime= M_{\mu}^\nu A_{\nu}$. According to my calculations:

$$M_{\mu}^\nu= \left( \begin{matrix} -\gamma&v\gamma&0&0\\ v\gamma&\gamma&0&0\\ 0&0&1&0\\ 0&0&0&1\\ \end{matrix}\right)$$

But according to Leonard Susskind's lectures: $M=\eta L\eta$

which doesn't agree with my calculations.

Suppose we have a vector $A^\mu$. This vector has 4 components (0 through 3). If we consider the Lorentz's transformation of each component, we could simplify them into matrix notation, ${A^\prime}^\mu=L^\mu{}_{\nu} A^\nu$, where:

$$L^\mu{}_{\nu}= \left( \begin {matrix}\gamma & -v\gamma & 0 & 0\\ -v\gamma & \gamma & 0 & 0\\ 0&0&1&0\\ 0&0&0&1\\ \end{matrix}\right)$$

where $\gamma=(1-\frac{v^2}{c^2})^{-\frac{1}{2}}$

Knowing that $A_{\mu}= \eta_{\mu\nu} A^\nu$ and

$$\eta_{\mu\nu}= \left( \begin{matrix} -1&0&0&0\\ 0&1&0&0\\ 0&0&1&0\\ 0&0&0&1\\ \end{matrix}\right)$$

we could say that $A_\mu^\prime= M_{\mu}^\nu A_{\nu}$. According to my calculations:

$$M_{\mu}^\nu= \left( \begin{matrix} -\gamma&v\gamma&0&0\\ v\gamma&\gamma&0&0\\ 0&0&1&0\\ 0&0&0&1\\ \end{matrix}\right)$$

But according to Leonard Susskind's lectures: $M=\eta L\eta$

which doesn't agree with my calculations.

cleaned up LaTeX and added brackets on matrices
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By Symmetry
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Suppose we have a vector $A^\mu$. This vector has 4 components (0 through 3). If we consider the Lorentz's transformation of each component, we could simplify them into matrix notation, $(A^\mu)^1=L^\mu_{\nu} A^\nu$${A^\prime}^\mu=L^\mu_{\nu} A^\nu$, (the exponent 1 on $A^\mu$ is just indicating that it's primed) where:

$L_{\nu}^\mu= $$ $$ \begin {matrix}\gamma & -v\gamma & 0 & 0\\ -v\gamma & \gamma & 0 & 0\\ 0&0&1&0\\ 0&0&0&1\\ \end{matrix}$$$L_{\nu}^\mu= \left( \begin {matrix}\gamma & -v\gamma & 0 & 0\\ -v\gamma & \gamma & 0 & 0\\ 0&0&1&0\\ 0&0&0&1\\ \end{matrix}\right)$$

($\gamma=$${(1-\frac{v^2}{c^2})^\frac{-1}{2}}$) where $\gamma=(1-\frac{v^2}{c^2})^{-\frac{1}{2}}$

Knowing that $A_{\mu}= \eta_{\mu\nu} A^\nu$ and

$\eta_{\mu\nu}= $$ \begin{matrix} -1&0&0&0\\ 0&1&0&0\\ 0&0&1&0\\ 0&0&0&1\\ \end{matrix}$$$\eta_{\mu\nu}= \left( \begin{matrix} -1&0&0&0\\ 0&1&0&0\\ 0&0&1&0\\ 0&0&0&1\\ \end{matrix}\right)$$

we could say that $(A_{\mu})^1= M_{\mu}^\nu A_{\nu}$$A_\mu^\prime= M_{\mu}^\nu A_{\nu}$. According to my calculations:

$M_{\mu}^\nu= $$ \begin{matrix} -\gamma&v\gamma&0&0\\ v\gamma&\gamma&0&0\\ 0&0&1&0\\ 0&0&0&1\\ \end{matrix}$$$M_{\mu}^\nu= \left( \begin{matrix} -\gamma&v\gamma&0&0\\ v\gamma&\gamma&0&0\\ 0&0&1&0\\ 0&0&0&1\\ \end{matrix}\right)$$

But according to Leonard Susskind's lectures: $M=\eta L\eta$

which doesn't agree with my calculations.

I'm sorry for my awfull notation and missing matrices' brackets (I'm still getting familiar with MathJax), I hope you can understand it and I'd be bery gratefull to anyone who can explain to me what I have done wrong.

Suppose we have a vector $A^\mu$. This vector has 4 components (0 through 3). If we consider the Lorentz's transformation of each component, we could simplify them into matrix notation, $(A^\mu)^1=L^\mu_{\nu} A^\nu$, (the exponent 1 on $A^\mu$ is just indicating that it's primed) where:

$L_{\nu}^\mu= $$ $$ \begin {matrix}\gamma & -v\gamma & 0 & 0\\ -v\gamma & \gamma & 0 & 0\\ 0&0&1&0\\ 0&0&0&1\\ \end{matrix}$

($\gamma=$${(1-\frac{v^2}{c^2})^\frac{-1}{2}}$)

Knowing that $A_{\mu}= \eta_{\mu\nu} A^\nu$ and

$\eta_{\mu\nu}= $$ \begin{matrix} -1&0&0&0\\ 0&1&0&0\\ 0&0&1&0\\ 0&0&0&1\\ \end{matrix}$

we could say that $(A_{\mu})^1= M_{\mu}^\nu A_{\nu}$. According to my calculations:

$M_{\mu}^\nu= $$ \begin{matrix} -\gamma&v\gamma&0&0\\ v\gamma&\gamma&0&0\\ 0&0&1&0\\ 0&0&0&1\\ \end{matrix}$

But according to Leonard Susskind's lectures: $M=\eta L\eta$

which doesn't agree with my calculations.

I'm sorry for my awfull notation and missing matrices' brackets (I'm still getting familiar with MathJax), I hope you can understand it and I'd be bery gratefull to anyone who can explain to me what I have done wrong.

Suppose we have a vector $A^\mu$. This vector has 4 components (0 through 3). If we consider the Lorentz's transformation of each component, we could simplify them into matrix notation, ${A^\prime}^\mu=L^\mu_{\nu} A^\nu$, where:

$$L_{\nu}^\mu= \left( \begin {matrix}\gamma & -v\gamma & 0 & 0\\ -v\gamma & \gamma & 0 & 0\\ 0&0&1&0\\ 0&0&0&1\\ \end{matrix}\right)$$

where $\gamma=(1-\frac{v^2}{c^2})^{-\frac{1}{2}}$

Knowing that $A_{\mu}= \eta_{\mu\nu} A^\nu$ and

$$\eta_{\mu\nu}= \left( \begin{matrix} -1&0&0&0\\ 0&1&0&0\\ 0&0&1&0\\ 0&0&0&1\\ \end{matrix}\right)$$

we could say that $A_\mu^\prime= M_{\mu}^\nu A_{\nu}$. According to my calculations:

$$M_{\mu}^\nu= \left( \begin{matrix} -\gamma&v\gamma&0&0\\ v\gamma&\gamma&0&0\\ 0&0&1&0\\ 0&0&0&1\\ \end{matrix}\right)$$

But according to Leonard Susskind's lectures: $M=\eta L\eta$

which doesn't agree with my calculations.

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Special Relativity - Matrix Notation

Suppose we have a vector $A^\mu$. This vector has 4 components (0 through 3). If we consider the Lorentz's transformation of each component, we could simplify them into matrix notation, $(A^\mu)^1=L^\mu_{\nu} A^\nu$, (the exponent 1 on $A^\mu$ is just indicating that it's primed) where:

$L_{\nu}^\mu= $$ $$ \begin {matrix}\gamma & -v\gamma & 0 & 0\\ -v\gamma & \gamma & 0 & 0\\ 0&0&1&0\\ 0&0&0&1\\ \end{matrix}$

($\gamma=$${(1-\frac{v^2}{c^2})^\frac{-1}{2}}$)

Knowing that $A_{\mu}= \eta_{\mu\nu} A^\nu$ and

$\eta_{\mu\nu}= $$ \begin{matrix} -1&0&0&0\\ 0&1&0&0\\ 0&0&1&0\\ 0&0&0&1\\ \end{matrix}$

we could say that $(A_{\mu})^1= M_{\mu}^\nu A_{\nu}$. According to my calculations:

$M_{\mu}^\nu= $$ \begin{matrix} -\gamma&v\gamma&0&0\\ v\gamma&\gamma&0&0\\ 0&0&1&0\\ 0&0&0&1\\ \end{matrix}$

But according to Leonard Susskind's lectures: $M=\eta L\eta$

which doesn't agree with my calculations.

I'm sorry for my awfull notation and missing matrices' brackets (I'm still getting familiar with MathJax), I hope you can understand it and I'd be bery gratefull to anyone who can explain to me what I have done wrong.