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OP's questions are quite broad. Here we will focus on OP's first question, but hopefully the reader gets some idea how this can be generalized.

  1. Consider the super inner product space $$V~:=~\mathbb{C}^{2,2|1}~=~V_0\oplus V_1, \qquad V_0~:=~\mathbb{C}^{2,2|0}, \qquad V_1~:=~\mathbb{C}^{0|1}, $$$$\begin{align}V~:=~&\mathbb{C}^{2,2|1}~=~V_0\oplus V_1, \cr V_0~:=~&\mathbb{C}^{2,2|0}, \cr V_1~:=~&\mathbb{C}^{0|1},\end{align} $$ which has 2+2=4 bosonic and 1 fermionic dimensions, and which is endowed with the standard metric $$ \eta ~=~ {\rm diag}(1,1,-1,-1|1) ~\in~ {\rm End}(\mathbb{C}^{2,2|1}).$$

  2. Supermatrices
    $$ m~=~\begin{pmatrix} m_{00} & m_{01} \cr m_{10} & m_{11} \end{pmatrix}, $$ corresponding to the super matrix algebra $$A~:=~{\rm End}(V)~=~A_0 \oplus A_1, \qquad A_0~:=~{\rm End}(V_0)\oplus {\rm End}(V_1), \qquad A_1~:=~{\cal L}(V_0;V_1)\oplus {\cal L}(V_1;V_0), $$$$\begin{align}A~:=~&{\rm End}(V)~=~A_0 \oplus A_1, \cr A_0~:=~&{\rm End}(V_0)\oplus {\rm End}(V_1), \cr A_1~:=~&{\cal L}(V_0;V_1)\oplus {\cal L}(V_1;V_0), \end{align} $$ of endomorphisms can be decomposed in two diagonal bosonic blocks $$m_{00}\in{\rm End}(V_0)\qquad\text{and}\qquad m_{11}\in{\rm End}(V_1),$$ and two off-diagonal fermionic blocks $m_{01}$ and $m_{10}$. The fermionic sector $A_1$ contains linear maps between $V_0$ and $V_1$.

  3. The super Lie group $$ U(2,2|1) ~~:=~~ \{U\in {\rm End}(\mathbb{C}^{2,2|1}) \mid U^{\dagger}\eta U = \eta \}$$ has corresponding super Lie algebra $$ u(2,2|1) ~~:=~~ \{m\in {\rm End}(\mathbb{C}^{2,2|1}) \mid m^{\dagger} =-\eta m \eta^{-1} \}.$$ (Warning: The super-Hermitian conjugation "$\dagger$" involves appropriate sign-factors.) The bosonic part of the super Lie algebra is $$A_0\cap u(2,2|1) ~\cong~ u(2,2) \oplus u(1)_R$$ $$~\cong~ su(2,2) \oplus u(1) \oplus u(1)_R ~\cong~ so(4,2) \oplus u(1) \oplus u(1)_R.$$$$\begin{align} A_0\cap u(2,2|1) ~\cong~& u(2,2) \oplus u(1)_R \cr ~\cong~& su(2,2) \oplus u(1) \oplus u(1)_R \cr ~\cong~& so(4,2) \oplus u(1) \oplus u(1)_R.\end{align}$$ Here subscript $R$ stands for the $R$-charge in the fermionic sector. The bosonic part of the super Lie group is $$ A_0 \cap U(2,2|1) ~\cong~ U(2,2) \times U(1)_R$$ $$~\cong~\frac{ SU(2,2)\times U(1)}{\mathbb{Z}_4} \times U(1)_R ~\cong~\frac{ SPIN(4,2)\times U(1)}{\mathbb{Z}_4} \times U(1)_R, $$$$\begin{align} A_0 \cap U(2,2|1) ~\cong~& U(2,2) \times U(1)_R \cr ~\cong~&\frac{ SU(2,2)\times U(1)}{\mathbb{Z}_4} \times U(1)_R \cr ~\cong~&\frac{ SPIN(4,2)\times U(1)}{\mathbb{Z}_4} \times U(1)_R, \end{align}$$ cf. e.g. this Phys.SE post and this Math.SE post.

  4. Now let us return to OP's first question. The super Lie group $$ SU(2,2|1) ~~:=~~ \{U\in U(2,2|1) \mid {\rm sdet} (U) =1\}$$ has corresponding super Lie algebra $$ su(2,2|1) ~~:=~~ \{m\in u(2,2|1) \mid {\rm str} (m) =0 \}.$$ The bosonic part of the super Lie algebra becomes $$A_0\cap su(2,2|1) ~\cong~ su(2,2) \oplus u(1)_R ~\cong~ so(4,2) \oplus u(1)_R.$$ This is the answer to OP's first question at the Lie algebra level.

  5. Concerning conformal groups without SUSY, see e.g. this Phys.SE post. In 3+1D the connected component that contains the identity element is $$ {\rm Conf}_0(3,1)~\cong~ SO^+(4,2)/\mathbb{Z}_2~\cong~SU(2,2)/[\mathbb{Z}_2\times \mathbb{Z}_2]. $$ For superconformal groups, see e.g. Wikipedia and nLab.

OP's questions are quite broad. Here we will focus on OP's first question, but hopefully the reader gets some idea how this can be generalized.

  1. Consider the super inner product space $$V~:=~\mathbb{C}^{2,2|1}~=~V_0\oplus V_1, \qquad V_0~:=~\mathbb{C}^{2,2|0}, \qquad V_1~:=~\mathbb{C}^{0|1}, $$ which has 2+2=4 bosonic and 1 fermionic dimensions, and which is endowed with the standard metric $$ \eta ~=~ {\rm diag}(1,1,-1,-1|1) ~\in~ {\rm End}(\mathbb{C}^{2,2|1}).$$

  2. Supermatrices
    $$ m~=~\begin{pmatrix} m_{00} & m_{01} \cr m_{10} & m_{11} \end{pmatrix}, $$ corresponding to the super matrix algebra $$A~:=~{\rm End}(V)~=~A_0 \oplus A_1, \qquad A_0~:=~{\rm End}(V_0)\oplus {\rm End}(V_1), \qquad A_1~:=~{\cal L}(V_0;V_1)\oplus {\cal L}(V_1;V_0), $$ of endomorphisms can be decomposed in two diagonal bosonic blocks $$m_{00}\in{\rm End}(V_0)\qquad\text{and}\qquad m_{11}\in{\rm End}(V_1),$$ and two off-diagonal fermionic blocks $m_{01}$ and $m_{10}$. The fermionic sector $A_1$ contains linear maps between $V_0$ and $V_1$.

  3. The super Lie group $$ U(2,2|1) ~~:=~~ \{U\in {\rm End}(\mathbb{C}^{2,2|1}) \mid U^{\dagger}\eta U = \eta \}$$ has corresponding super Lie algebra $$ u(2,2|1) ~~:=~~ \{m\in {\rm End}(\mathbb{C}^{2,2|1}) \mid m^{\dagger} =-\eta m \eta^{-1} \}.$$ (Warning: The super-Hermitian conjugation "$\dagger$" involves appropriate sign-factors.) The bosonic part of the super Lie algebra is $$A_0\cap u(2,2|1) ~\cong~ u(2,2) \oplus u(1)_R$$ $$~\cong~ su(2,2) \oplus u(1) \oplus u(1)_R ~\cong~ so(4,2) \oplus u(1) \oplus u(1)_R.$$ Here subscript $R$ stands for the $R$-charge in the fermionic sector. The bosonic part of the super Lie group is $$ A_0 \cap U(2,2|1) ~\cong~ U(2,2) \times U(1)_R$$ $$~\cong~\frac{ SU(2,2)\times U(1)}{\mathbb{Z}_4} \times U(1)_R ~\cong~\frac{ SPIN(4,2)\times U(1)}{\mathbb{Z}_4} \times U(1)_R, $$ cf. e.g. this Phys.SE post and this Math.SE post.

  4. Now let us return to OP's first question. The super Lie group $$ SU(2,2|1) ~~:=~~ \{U\in U(2,2|1) \mid {\rm sdet} (U) =1\}$$ has corresponding super Lie algebra $$ su(2,2|1) ~~:=~~ \{m\in u(2,2|1) \mid {\rm str} (m) =0 \}.$$ The bosonic part of the super Lie algebra becomes $$A_0\cap su(2,2|1) ~\cong~ su(2,2) \oplus u(1)_R ~\cong~ so(4,2) \oplus u(1)_R.$$ This is the answer to OP's first question at the Lie algebra level.

  5. Concerning conformal groups without SUSY, see e.g. this Phys.SE post. In 3+1D the connected component that contains the identity element is $$ {\rm Conf}_0(3,1)~\cong~ SO^+(4,2)/\mathbb{Z}_2~\cong~SU(2,2)/[\mathbb{Z}_2\times \mathbb{Z}_2]. $$ For superconformal groups, see e.g. Wikipedia and nLab.

OP's questions are quite broad. Here we will focus on OP's first question, but hopefully the reader gets some idea how this can be generalized.

  1. Consider the super inner product space $$\begin{align}V~:=~&\mathbb{C}^{2,2|1}~=~V_0\oplus V_1, \cr V_0~:=~&\mathbb{C}^{2,2|0}, \cr V_1~:=~&\mathbb{C}^{0|1},\end{align} $$ which has 2+2=4 bosonic and 1 fermionic dimensions, and which is endowed with the standard metric $$ \eta ~=~ {\rm diag}(1,1,-1,-1|1) ~\in~ {\rm End}(\mathbb{C}^{2,2|1}).$$

  2. Supermatrices
    $$ m~=~\begin{pmatrix} m_{00} & m_{01} \cr m_{10} & m_{11} \end{pmatrix}, $$ corresponding to the super matrix algebra $$\begin{align}A~:=~&{\rm End}(V)~=~A_0 \oplus A_1, \cr A_0~:=~&{\rm End}(V_0)\oplus {\rm End}(V_1), \cr A_1~:=~&{\cal L}(V_0;V_1)\oplus {\cal L}(V_1;V_0), \end{align} $$ of endomorphisms can be decomposed in two diagonal bosonic blocks $$m_{00}\in{\rm End}(V_0)\qquad\text{and}\qquad m_{11}\in{\rm End}(V_1),$$ and two off-diagonal fermionic blocks $m_{01}$ and $m_{10}$. The fermionic sector $A_1$ contains linear maps between $V_0$ and $V_1$.

  3. The super Lie group $$ U(2,2|1) ~~:=~~ \{U\in {\rm End}(\mathbb{C}^{2,2|1}) \mid U^{\dagger}\eta U = \eta \}$$ has corresponding super Lie algebra $$ u(2,2|1) ~~:=~~ \{m\in {\rm End}(\mathbb{C}^{2,2|1}) \mid m^{\dagger} =-\eta m \eta^{-1} \}.$$ (Warning: The super-Hermitian conjugation "$\dagger$" involves appropriate sign-factors.) The bosonic part of the super Lie algebra is $$\begin{align} A_0\cap u(2,2|1) ~\cong~& u(2,2) \oplus u(1)_R \cr ~\cong~& su(2,2) \oplus u(1) \oplus u(1)_R \cr ~\cong~& so(4,2) \oplus u(1) \oplus u(1)_R.\end{align}$$ Here subscript $R$ stands for the $R$-charge in the fermionic sector. The bosonic part of the super Lie group is $$\begin{align} A_0 \cap U(2,2|1) ~\cong~& U(2,2) \times U(1)_R \cr ~\cong~&\frac{ SU(2,2)\times U(1)}{\mathbb{Z}_4} \times U(1)_R \cr ~\cong~&\frac{ SPIN(4,2)\times U(1)}{\mathbb{Z}_4} \times U(1)_R, \end{align}$$ cf. e.g. this Phys.SE post and this Math.SE post.

  4. Now let us return to OP's first question. The super Lie group $$ SU(2,2|1) ~~:=~~ \{U\in U(2,2|1) \mid {\rm sdet} (U) =1\}$$ has corresponding super Lie algebra $$ su(2,2|1) ~~:=~~ \{m\in u(2,2|1) \mid {\rm str} (m) =0 \}.$$ The bosonic part of the super Lie algebra becomes $$A_0\cap su(2,2|1) ~\cong~ su(2,2) \oplus u(1)_R ~\cong~ so(4,2) \oplus u(1)_R.$$ This is the answer to OP's first question at the Lie algebra level.

  5. Concerning conformal groups without SUSY, see e.g. this Phys.SE post. In 3+1D the connected component that contains the identity element is $$ {\rm Conf}_0(3,1)~\cong~ SO^+(4,2)/\mathbb{Z}_2~\cong~SU(2,2)/[\mathbb{Z}_2\times \mathbb{Z}_2]. $$ For superconformal groups, see e.g. Wikipedia and nLab.

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Qmechanic
  • 212.8k
  • 48
  • 589
  • 2.3k

OP's questions are quite broad. Here we will focus on OP's first question, but hopefully the reader gets some idea how this can be generalized.

  1. Consider the super inner product space $$V~:=~\mathbb{C}^{2,2|1}~=~V_0\oplus V_1, \qquad V_0~:=~\mathbb{C}^{2,2|0}, \qquad V_1~:=~\mathbb{C}^{0|1}, $$ which has 2+2=4 bosonic and 1 fermionic dimensions, and which is endowed with the standard metric $$ \eta ~=~ {\rm diag}(1,1,-1,-1|1) ~\in~ {\rm End}(\mathbb{C}^{2,2|1}).$$

  2. Supermatrices
    $$ m~=~\begin{pmatrix} m_{00} & m_{01} \cr m_{10} & m_{11} \end{pmatrix}, $$ corresponding to the super matrix algebra $$A~:=~{\rm End}(V)~=~A_0 \oplus A_1, \qquad A_0~:=~{\rm End}(V_0)\oplus {\rm End}(V_1), \qquad A_1~:=~{\cal L}(V_0;V_1)\oplus {\cal L}(V_1;V_0), $$ of endomorphisms can be decomposed in two diagonal bosonic blocks $$m_{00}\in{\rm End}(V_0)\qquad\text{and}\qquad m_{11}\in{\rm End}(V_1),$$ and two off-diagonal fermionic blocks $m_{01}$ and $m_{10}$. The fermionic sector $A_1$ contains linear maps between $V_0$ and $V_1$.

  3. The super Lie group $$ U(2,2|1) ~~:=~~ \{U\in {\rm End}(\mathbb{C}^{2,2|1}) \mid U^{\dagger}\eta U = {\bf 1} \}$$$$ U(2,2|1) ~~:=~~ \{U\in {\rm End}(\mathbb{C}^{2,2|1}) \mid U^{\dagger}\eta U = \eta \}$$ has corresponding super Lie algebra $$ u(2,2|1) ~~:=~~ \{m\in {\rm End}(\mathbb{C}^{2,2|1}) \mid m^{\dagger} =-\eta m \eta^{-1} \}.$$ (Warning: The super-Hermitian conjugation "$\dagger$" involves appropriate sign-factors.) The bosonic part of the super Lie algebra is $$A_0\cap u(2,2|1) ~\cong~ u(2,2) \oplus u(1)_R$$ $$~\cong~ su(2,2) \oplus u(1) \oplus u(1)_R ~\cong~ so(4,2) \oplus u(1) \oplus u(1)_R.$$ Here subscript $R$ stands for the $R$-charge in the fermionic sector. The bosonic part of the super Lie group is $$ A_0 \cap U(2,2|1) ~\cong~ U(2,2) \times U(1)_R$$ $$~\cong~\frac{ SU(2,2)\times U(1)}{\mathbb{Z}_4} \times U(1)_R ~\cong~\frac{ SPIN(4,2)\times U(1)}{\mathbb{Z}_4} \times U(1)_R, $$ cf. e.g. this Phys.SE post and this Math.SE post.

  4. Now let us return to OP's first question. The super Lie group $$ SU(2,2|1) ~~:=~~ \{U\in U(2,2|1) \mid {\rm sdet} (U) =1\}$$ has corresponding super Lie algebra $$ su(2,2|1) ~~:=~~ \{m\in u(2,2|1) \mid {\rm str} (m) =0 \}.$$ The bosonic part of the super Lie algebra becomes $$A_0\cap su(2,2|1) ~\cong~ su(2,2) \oplus u(1)_R ~\cong~ so(4,2) \oplus u(1)_R.$$ This is the answer to OP's first question at the Lie algebra level.

  5. Concerning conformal groups without SUSY, see e.g. this Phys.SE post. In 3+1D the connected component that contains the identity element is $$ {\rm Conf}_0(3,1)~\cong~ SO^+(4,2)/\mathbb{Z}_2~\cong~SU(2,2)/[\mathbb{Z}_2\times \mathbb{Z}_2]. $$ For superconformal groups, see e.g. Wikipedia and nLab.

OP's questions are quite broad. Here we will focus on OP's first question, but hopefully the reader gets some idea how this can be generalized.

  1. Consider the super inner product space $$V~:=~\mathbb{C}^{2,2|1}~=~V_0\oplus V_1, \qquad V_0~:=~\mathbb{C}^{2,2|0}, \qquad V_1~:=~\mathbb{C}^{0|1}, $$ which has 2+2=4 bosonic and 1 fermionic dimensions, and which is endowed with the standard metric $$ \eta ~=~ {\rm diag}(1,1,-1,-1|1) ~\in~ {\rm End}(\mathbb{C}^{2,2|1}).$$

  2. Supermatrices
    $$ m~=~\begin{pmatrix} m_{00} & m_{01} \cr m_{10} & m_{11} \end{pmatrix}, $$ corresponding to the super matrix algebra $$A~:=~{\rm End}(V)~=~A_0 \oplus A_1, \qquad A_0~:=~{\rm End}(V_0)\oplus {\rm End}(V_1), \qquad A_1~:=~{\cal L}(V_0;V_1)\oplus {\cal L}(V_1;V_0), $$ of endomorphisms can be decomposed in two diagonal bosonic blocks $$m_{00}\in{\rm End}(V_0)\qquad\text{and}\qquad m_{11}\in{\rm End}(V_1),$$ and two off-diagonal fermionic blocks $m_{01}$ and $m_{10}$. The fermionic sector $A_1$ contains linear maps between $V_0$ and $V_1$.

  3. The super Lie group $$ U(2,2|1) ~~:=~~ \{U\in {\rm End}(\mathbb{C}^{2,2|1}) \mid U^{\dagger}\eta U = {\bf 1} \}$$ has corresponding super Lie algebra $$ u(2,2|1) ~~:=~~ \{m\in {\rm End}(\mathbb{C}^{2,2|1}) \mid m^{\dagger} =-\eta m \eta^{-1} \}.$$ (Warning: The super-Hermitian conjugation "$\dagger$" involves appropriate sign-factors.) The bosonic part of the super Lie algebra is $$A_0\cap u(2,2|1) ~\cong~ u(2,2) \oplus u(1)_R$$ $$~\cong~ su(2,2) \oplus u(1) \oplus u(1)_R ~\cong~ so(4,2) \oplus u(1) \oplus u(1)_R.$$ Here subscript $R$ stands for the $R$-charge in the fermionic sector. The bosonic part of the super Lie group is $$ A_0 \cap U(2,2|1) ~\cong~ U(2,2) \times U(1)_R$$ $$~\cong~\frac{ SU(2,2)\times U(1)}{\mathbb{Z}_4} \times U(1)_R ~\cong~\frac{ SPIN(4,2)\times U(1)}{\mathbb{Z}_4} \times U(1)_R, $$ cf. e.g. this Phys.SE post and this Math.SE post.

  4. Now let us return to OP's first question. The super Lie group $$ SU(2,2|1) ~~:=~~ \{U\in U(2,2|1) \mid {\rm sdet} (U) =1\}$$ has corresponding super Lie algebra $$ su(2,2|1) ~~:=~~ \{m\in u(2,2|1) \mid {\rm str} (m) =0 \}.$$ The bosonic part of the super Lie algebra becomes $$A_0\cap su(2,2|1) ~\cong~ su(2,2) \oplus u(1)_R ~\cong~ so(4,2) \oplus u(1)_R.$$ This is the answer to OP's first question at the Lie algebra level.

  5. Concerning conformal groups without SUSY, see e.g. this Phys.SE post. In 3+1D the connected component that contains the identity element is $$ {\rm Conf}_0(3,1)~\cong~ SO^+(4,2)/\mathbb{Z}_2~\cong~SU(2,2)/[\mathbb{Z}_2\times \mathbb{Z}_2]. $$ For superconformal groups, see e.g. Wikipedia and nLab.

OP's questions are quite broad. Here we will focus on OP's first question, but hopefully the reader gets some idea how this can be generalized.

  1. Consider the super inner product space $$V~:=~\mathbb{C}^{2,2|1}~=~V_0\oplus V_1, \qquad V_0~:=~\mathbb{C}^{2,2|0}, \qquad V_1~:=~\mathbb{C}^{0|1}, $$ which has 2+2=4 bosonic and 1 fermionic dimensions, and which is endowed with the standard metric $$ \eta ~=~ {\rm diag}(1,1,-1,-1|1) ~\in~ {\rm End}(\mathbb{C}^{2,2|1}).$$

  2. Supermatrices
    $$ m~=~\begin{pmatrix} m_{00} & m_{01} \cr m_{10} & m_{11} \end{pmatrix}, $$ corresponding to the super matrix algebra $$A~:=~{\rm End}(V)~=~A_0 \oplus A_1, \qquad A_0~:=~{\rm End}(V_0)\oplus {\rm End}(V_1), \qquad A_1~:=~{\cal L}(V_0;V_1)\oplus {\cal L}(V_1;V_0), $$ of endomorphisms can be decomposed in two diagonal bosonic blocks $$m_{00}\in{\rm End}(V_0)\qquad\text{and}\qquad m_{11}\in{\rm End}(V_1),$$ and two off-diagonal fermionic blocks $m_{01}$ and $m_{10}$. The fermionic sector $A_1$ contains linear maps between $V_0$ and $V_1$.

  3. The super Lie group $$ U(2,2|1) ~~:=~~ \{U\in {\rm End}(\mathbb{C}^{2,2|1}) \mid U^{\dagger}\eta U = \eta \}$$ has corresponding super Lie algebra $$ u(2,2|1) ~~:=~~ \{m\in {\rm End}(\mathbb{C}^{2,2|1}) \mid m^{\dagger} =-\eta m \eta^{-1} \}.$$ (Warning: The super-Hermitian conjugation "$\dagger$" involves appropriate sign-factors.) The bosonic part of the super Lie algebra is $$A_0\cap u(2,2|1) ~\cong~ u(2,2) \oplus u(1)_R$$ $$~\cong~ su(2,2) \oplus u(1) \oplus u(1)_R ~\cong~ so(4,2) \oplus u(1) \oplus u(1)_R.$$ Here subscript $R$ stands for the $R$-charge in the fermionic sector. The bosonic part of the super Lie group is $$ A_0 \cap U(2,2|1) ~\cong~ U(2,2) \times U(1)_R$$ $$~\cong~\frac{ SU(2,2)\times U(1)}{\mathbb{Z}_4} \times U(1)_R ~\cong~\frac{ SPIN(4,2)\times U(1)}{\mathbb{Z}_4} \times U(1)_R, $$ cf. e.g. this Phys.SE post and this Math.SE post.

  4. Now let us return to OP's first question. The super Lie group $$ SU(2,2|1) ~~:=~~ \{U\in U(2,2|1) \mid {\rm sdet} (U) =1\}$$ has corresponding super Lie algebra $$ su(2,2|1) ~~:=~~ \{m\in u(2,2|1) \mid {\rm str} (m) =0 \}.$$ The bosonic part of the super Lie algebra becomes $$A_0\cap su(2,2|1) ~\cong~ su(2,2) \oplus u(1)_R ~\cong~ so(4,2) \oplus u(1)_R.$$ This is the answer to OP's first question at the Lie algebra level.

  5. Concerning conformal groups without SUSY, see e.g. this Phys.SE post. In 3+1D the connected component that contains the identity element is $$ {\rm Conf}_0(3,1)~\cong~ SO^+(4,2)/\mathbb{Z}_2~\cong~SU(2,2)/[\mathbb{Z}_2\times \mathbb{Z}_2]. $$ For superconformal groups, see e.g. Wikipedia and nLab.

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Qmechanic
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OP's questions are quite broad. Here we will focus on OP's first question, but hopefully the reader gets some idea how this can be generalized.

  1. Consider the super inner product space $$V~:=~\mathbb{C}^{2,2|1}~=~V_0\oplus V_1, \qquad V_0~:=~\mathbb{C}^{2,2|0}, \qquad V_1~:=~\mathbb{C}^{0|1}, $$ which has 2+2=4 bosonic and 1 fermionic dimensions, and which is endowed with the standard metric $$ \eta ~=~ {\rm diag}(1,1,-1,-1|1) ~\in~ {\rm End}(\mathbb{C}^{2,2|1}).$$

  2. Supermatrices
    $$ m~=~\begin{pmatrix} m_{00} & m_{01} \cr m_{10} & m_{11} \end{pmatrix}, $$ corresponding to the super matrix algebra $$A~:=~{\rm End}(V)~=~A_0 \oplus A_1, \qquad A_0~:=~{\rm End}(V_0)\oplus {\rm End}(V_1), \qquad A_1~:=~{\cal L}(V_0;V_1)\oplus {\cal L}(V_1;V_0), $$ of endomorphisms can be decomposed in two diagonal bosonic blocks $$m_{00}\in{\rm End}(V_0)\qquad\text{and}\qquad m_{11}\in{\rm End}(V_1),$$ and two off-diagonal fermionic blocks $m_{01}$ and $m_{10}$. The fermionic sector $A_1$ contains linear maps between $V_0$ and $V_1$.

  3. The super Lie group $$ U(2,2|1) ~~:=~~ \{U\in {\rm End}(\mathbb{C}^{2,2|1}) \mid U^{\dagger}\eta U = {\bf 1} \}$$ has corresponding super Lie algebra $$ u(2,2|1) ~~:=~~ \{m\in {\rm End}(\mathbb{C}^{2,2|1}) \mid m^{\dagger} =-\eta m \eta^{-1} \}.$$ The(Warning: The super-Hermitian conjugation "$\dagger$" involves appropriate sign-factors.) The bosonic part of the super Lie algebra is $$A_0\cap u(2,2|1) ~\cong~ u(2,2) \oplus u(1)_R$$ $$~\cong~ su(2,2) \oplus u(1) \oplus u(1)_R ~\cong~ so(4,2) \oplus u(1) \oplus u(1)_R.$$ Here subscript $R$ stands for the $R$-charge in the fermionic sector. The bosonic part of the super Lie group is $$ A_0 \cap U(2,2|1) ~\cong~ U(2,2) \times U(1)_R$$ $$~\cong~\frac{ SU(2,2)\times U(1)}{\mathbb{Z}_4} \times U(1)_R ~\cong~\frac{ SPIN(4,2)\times U(1)}{\mathbb{Z}_4} \times U(1)_R, $$ cf. e.g. this Phys.SE post and this Math.SE post.

  4. Now let us return to OP's first question. The super Lie group $$ SU(2,2|1) ~~:=~~ \{U\in U(2,2|1) \mid {\rm sdet} (U) =1\}$$ has corresponding super Lie algebra $$ su(2,2|1) ~~:=~~ \{m\in u(2,2|1) \mid {\rm str} (m) =0 \}.$$ The bosonic part of the super Lie algebra becomes $$A_0\cap su(2,2|1) ~\cong~ su(2,2) \oplus u(1) ~\cong~ so(4,2) \oplus u(1).$$$$A_0\cap su(2,2|1) ~\cong~ su(2,2) \oplus u(1)_R ~\cong~ so(4,2) \oplus u(1)_R.$$ This is the answer to OP's first question at the Lie algebra level. The $u(1)$ charge is a linear combination of bosonic and fermionic $u(1)$ charges in order to make the supertrace vanish.

  5. Concerning conformal groups without SUSY, see e.g. this Phys.SE post. For In 3+1D the connected component that contains the identity element is $$ {\rm Conf}_0(3,1)~\cong~ SO^+(4,2)/\mathbb{Z}_2~\cong~SU(2,2)/[\mathbb{Z}_2\times \mathbb{Z}_2]. $$ For superconformal groups, see e.g. Wikipedia and nLab.

OP's questions are quite broad. Here we will focus on OP's first question, but hopefully the reader gets some idea how this can be generalized.

  1. Consider the super inner product space $$V~:=~\mathbb{C}^{2,2|1}~=~V_0\oplus V_1, \qquad V_0~:=~\mathbb{C}^{2,2|0}, \qquad V_1~:=~\mathbb{C}^{0|1}, $$ which has 2+2=4 bosonic and 1 fermionic dimensions, and which is endowed with the standard metric $$ \eta ~=~ {\rm diag}(1,1,-1,-1|1) ~\in~ {\rm End}(\mathbb{C}^{2,2|1}).$$

  2. Supermatrices
    $$ m~=~\begin{pmatrix} m_{00} & m_{01} \cr m_{10} & m_{11} \end{pmatrix}, $$ corresponding to the super matrix algebra $$A~:=~{\rm End}(V)~=~A_0 \oplus A_1, \qquad A_0~:=~{\rm End}(V_0)\oplus {\rm End}(V_1), \qquad A_1~:=~{\cal L}(V_0;V_1)\oplus {\cal L}(V_1;V_0), $$ of endomorphisms can be decomposed in two diagonal bosonic blocks $$m_{00}\in{\rm End}(V_0)\qquad\text{and}\qquad m_{11}\in{\rm End}(V_1),$$ and two off-diagonal fermionic blocks $m_{01}$ and $m_{10}$.

  3. The super Lie group $$ U(2,2|1) ~~:=~~ \{U\in {\rm End}(\mathbb{C}^{2,2|1}) \mid U^{\dagger}\eta U = {\bf 1} \}$$ has corresponding super Lie algebra $$ u(2,2|1) ~~:=~~ \{m\in {\rm End}(\mathbb{C}^{2,2|1}) \mid m^{\dagger} =-\eta m \eta^{-1} \}.$$ The bosonic part of the super Lie algebra is $$A_0\cap u(2,2|1) ~\cong~ u(2,2) \oplus u(1)_R$$ $$~\cong~ su(2,2) \oplus u(1) \oplus u(1)_R ~\cong~ so(4,2) \oplus u(1) \oplus u(1)_R.$$ Here subscript $R$ stands for the $R$-charge in the fermionic sector. The bosonic part of the super Lie group is $$ A_0 \cap U(2,2|1) ~\cong~ U(2,2) \times U(1)_R$$ $$~\cong~\frac{ SU(2,2)\times U(1)}{\mathbb{Z}_4} \times U(1)_R ~\cong~\frac{ SPIN(4,2)\times U(1)}{\mathbb{Z}_4} \times U(1)_R, $$ cf. e.g. this Phys.SE post and this Math.SE post.

  4. Now let us return to OP's first question. The super Lie group $$ SU(2,2|1) ~~:=~~ \{U\in U(2,2|1) \mid {\rm sdet} (U) =1\}$$ has corresponding super Lie algebra $$ su(2,2|1) ~~:=~~ \{m\in u(2,2|1) \mid {\rm str} (m) =0 \}.$$ The bosonic part of the super Lie algebra becomes $$A_0\cap su(2,2|1) ~\cong~ su(2,2) \oplus u(1) ~\cong~ so(4,2) \oplus u(1).$$ This is the answer to OP's first question at the Lie algebra level. The $u(1)$ charge is a linear combination of bosonic and fermionic $u(1)$ charges in order to make the supertrace vanish.

  5. Concerning conformal groups, see e.g. this Phys.SE post. For superconformal groups, see e.g. Wikipedia and nLab.

OP's questions are quite broad. Here we will focus on OP's first question, but hopefully the reader gets some idea how this can be generalized.

  1. Consider the super inner product space $$V~:=~\mathbb{C}^{2,2|1}~=~V_0\oplus V_1, \qquad V_0~:=~\mathbb{C}^{2,2|0}, \qquad V_1~:=~\mathbb{C}^{0|1}, $$ which has 2+2=4 bosonic and 1 fermionic dimensions, and which is endowed with the standard metric $$ \eta ~=~ {\rm diag}(1,1,-1,-1|1) ~\in~ {\rm End}(\mathbb{C}^{2,2|1}).$$

  2. Supermatrices
    $$ m~=~\begin{pmatrix} m_{00} & m_{01} \cr m_{10} & m_{11} \end{pmatrix}, $$ corresponding to the super matrix algebra $$A~:=~{\rm End}(V)~=~A_0 \oplus A_1, \qquad A_0~:=~{\rm End}(V_0)\oplus {\rm End}(V_1), \qquad A_1~:=~{\cal L}(V_0;V_1)\oplus {\cal L}(V_1;V_0), $$ of endomorphisms can be decomposed in two diagonal bosonic blocks $$m_{00}\in{\rm End}(V_0)\qquad\text{and}\qquad m_{11}\in{\rm End}(V_1),$$ and two off-diagonal fermionic blocks $m_{01}$ and $m_{10}$. The fermionic sector $A_1$ contains linear maps between $V_0$ and $V_1$.

  3. The super Lie group $$ U(2,2|1) ~~:=~~ \{U\in {\rm End}(\mathbb{C}^{2,2|1}) \mid U^{\dagger}\eta U = {\bf 1} \}$$ has corresponding super Lie algebra $$ u(2,2|1) ~~:=~~ \{m\in {\rm End}(\mathbb{C}^{2,2|1}) \mid m^{\dagger} =-\eta m \eta^{-1} \}.$$ (Warning: The super-Hermitian conjugation "$\dagger$" involves appropriate sign-factors.) The bosonic part of the super Lie algebra is $$A_0\cap u(2,2|1) ~\cong~ u(2,2) \oplus u(1)_R$$ $$~\cong~ su(2,2) \oplus u(1) \oplus u(1)_R ~\cong~ so(4,2) \oplus u(1) \oplus u(1)_R.$$ Here subscript $R$ stands for the $R$-charge in the fermionic sector. The bosonic part of the super Lie group is $$ A_0 \cap U(2,2|1) ~\cong~ U(2,2) \times U(1)_R$$ $$~\cong~\frac{ SU(2,2)\times U(1)}{\mathbb{Z}_4} \times U(1)_R ~\cong~\frac{ SPIN(4,2)\times U(1)}{\mathbb{Z}_4} \times U(1)_R, $$ cf. e.g. this Phys.SE post and this Math.SE post.

  4. Now let us return to OP's first question. The super Lie group $$ SU(2,2|1) ~~:=~~ \{U\in U(2,2|1) \mid {\rm sdet} (U) =1\}$$ has corresponding super Lie algebra $$ su(2,2|1) ~~:=~~ \{m\in u(2,2|1) \mid {\rm str} (m) =0 \}.$$ The bosonic part of the super Lie algebra becomes $$A_0\cap su(2,2|1) ~\cong~ su(2,2) \oplus u(1)_R ~\cong~ so(4,2) \oplus u(1)_R.$$ This is the answer to OP's first question at the Lie algebra level.

  5. Concerning conformal groups without SUSY, see e.g. this Phys.SE post. In 3+1D the connected component that contains the identity element is $$ {\rm Conf}_0(3,1)~\cong~ SO^+(4,2)/\mathbb{Z}_2~\cong~SU(2,2)/[\mathbb{Z}_2\times \mathbb{Z}_2]. $$ For superconformal groups, see e.g. Wikipedia and nLab.

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