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\begin{document}
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{\LARGE\bf Cheat Sheet $\beta$}\hfill
\parbox[b]{5.2in}{\tiny
  \null\hfill verification at {\tt 2014-06/CheatSheetBeta-Verification.nb},
    {\tt 2014-05/GoodFormulas/Demo.nb}
  \newline\null\hfill \sheeturl; initiated 24/3/13;
    continues \href{http://drorbn.net/AcademicPensieve/2014-06/}{2014-06};
    continued \href{http://drorbn.net/AcademicPensieve/2015-04/}{2015-04};
    modified \today, \ampmtime
}

\vskip -10pt
\rule{\textwidth}{1pt}
\textbf{$\sigma$ calculus.}
\hfill $\sigma_1\ast\sigma_2=\sigma_1\cup\sigma_2$,
\quad $tm^{uv}_w=({T_u,T_v\to T_w})$,
\quad $hm^{xy}_z\colon\sigma\mapsto(\sigma\remove\{x,y\})\cup(z\to\sigma_x\sigma_y),$
\quad $tha^{ux}=I,$
\quad $R^\pm_{ux}\mapsto T_u^{\pm 1}$

\vskip 1mm
\textbf{$\beta$-calculus.} \hfill Constraints.
$\bullet$ Sum of column $x$ is $\sigma_x-1$.
\quad $\bullet$ At $T_\ast=1$, $\omega=1$ and $A=0$.

\vskip 1mm  $\displaystyle
  \begin{array}{c|c}\omega_1&H_1\\\hline T_1&A_1\end{array}
  \ast
  \begin{array}{c|c}\omega_2&H_2\\\hline T_2&A_2\end{array}
  \underset{\beta}{=}
  \begin{array}{c|cc}
    \omega_1\omega_2 & H_1 & H_2 \\
    \hline
    T_1 & A_1 & 0 \\
    T_2 & 0 & A_2
  \end{array}
$
\hfill $\displaystyle
  \begin{CD}
    \begin{array}{c|c}
      \omega & H \\
      \hline
      u & \alpha \\
      v & \beta \\
      T & \Xi
    \end{array}
    @>tm^{uv}_w>\beta>
    \left(\!\begin{array}{c|c}
      \omega & H \\
      \hline
      w & \alpha+\beta \\
      T & \Xi
    \end{array}\!\right)_{T_u,T_v\to T_w}
  \end{CD}
$
\hfill $\displaystyle
  \begin{CD}
    \begin{array}{c|ccc}
      \omega & x & y & H \\
      \hline
      T & \alpha & \beta & \Xi
    \end{array}
    @>{hm^{xy}_z}>\beta>
    \begin{array}{c|cc}
      \omega & z & H \\
      \hline
      T & \alpha+\sigma_x\beta & \Xi
    \end{array}
  \end{CD}
$

\hfill$\displaystyle
  \begin{CD}
    \begin{array}{c|cc}
      \omega & x & H \\
      \hline
      u & \alpha & \theta \\
      T & \phi & \Xi
    \end{array}
    @>{tha^{ux}}>\beta\atop\nu\coloneqq 1+\alpha>
%    \begin{array}{c|cc}
%      \omega\epsilon & x & H \\
%      \hline
%      u & \alpha(1+\langle\gamma\rangle/\epsilon)
%        & \beta(1+\langle\gamma\rangle/\epsilon) \\
%      T & \gamma/\epsilon & \delta-\gamma\beta/\epsilon
%    \end{array} =
    \begin{array}{c|cc}
      \nu\omega & x & H \\
      \hline
      u & \sigma_x\alpha/\nu & \sigma_x\theta/\nu \\
      T & \phi/\nu & \Xi-\phi\theta/\nu
    \end{array}
  \end{CD}
$
\hfill $\displaystyle
  \rho^\pm_{ux} \underset{\beta}{=}
  \begin{array}{c|c}
    1 & x \\
    \hline
    u & T_u^{\pm 1}-1
  \end{array}
$\hfill\null

\rule{\textwidth}{1pt}

\textbf{Gassner calculus $\Gamma$.}
\hfill Preserves $C_1\coloneqq[\text{col sum}=1]$ ($\Leftrightarrow$OC) and $\green\checkmark$ $C_2\coloneqq[\forall a,b,\, (T_a-1)\mid(A_{ab}-\delta_{ab}\sigma_b)]$

\hfill $\displaystyle
  \begin{CD}
    \left(\!\begin{array}{c|cc}
      \nu\omega & c & S \\
      \hline
      c & \beta+\alpha\delta/\nu & \theta+\alpha\epsilon/\nu \\
      S & \psi+\delta\phi/\nu & \Xi+\epsilon\phi/\nu
    \end{array}\!\right)_{T_a,T_b\to T_c}
    \hspace{-7mm}
    @<{m^{ba}_{c}}<\nu\coloneqq 1-\gamma<
    \begin{array}{c|ccc}
      \omega & a & b & S \\
      \hline
      a & \alpha & \beta & \theta \\
      b & \gamma & \delta & \epsilon \\
      S & \phi & \psi & \Xi
    \end{array}
    @>{m^{ab}_{c}}>\mu\coloneqq 1-\beta>
    \left(\!\begin{array}{c|cc}
      \mu\omega & c & S \\
      \hline
      c & \gamma+\alpha\delta/\mu & \epsilon+\delta\theta/\mu \\
      S & \phi+\alpha\psi/\mu & \Xi+\psi\theta/\mu
    \end{array}\!\right)_{T_a,T_b\to T_c}
    \hspace{-8mm}
  \end{CD}
$
\hfill$R^{\pm}_{ab} \underset{\gamma}{=} \begin{array}{c|cc}
  1 & a & b \\
  \hline
  a & 1 & 1-T_a^{\pm 1} \\
  b & 0 & T_a^{\pm 1}
\end{array}$

$\displaystyle
  \begin{CD}
    \begin{array}{c|cc}
      \omega & a & S \\
      \hline
      a & \alpha & \theta \\
      S & \phi & \Xi
    \end{array}
    @>q\Delta^a_{bc}>{\mu\coloneqq T_a-1\atop\nu\coloneqq \alpha-\sigma_a}>
    \left(\begin{array}{c|ccc}
      \omega & b & c & S \\
      \hline
      b &
        (\sigma_a-\alpha T_a-\nu T_c)/\mu &
        (T_b-1)T_c\nu/\mu &
        (T_b-1)T_c\theta/\mu \\
      c &
        (T_c-1)\nu/\mu &
        (\alpha-\sigma_a T_a-\nu T_c)/\mu &
        (T_c-1)\theta/\mu \\
      S & \phi & \phi & \Xi
    \end{array}\right)_{T_a\mapsto T_bT_c}
  \end{CD}
$
\hfill\parbox{2.1in}{Satisfies:
$\green\checkmark$ $R^+_{13}\act q\Delta^1_{12}=R^+_{23}\#R^+_{13}$.
\newline$\green\checkmark$ $R^-_{13}\act q\Delta^1_{12}=R^-_{13}\#R^-_{23}$.
\newline$\green\checkmark$ $q\Delta^a_{a_1a_2}\act q\Delta^b_{b_1b_2}\act m^{a_1b_1}_{c_1}\act m^{a_2b_2}_{c_2}$ \newline\null\quad$=m^{ab}_c\act q\Delta^c_{c_1c_2}$.
}

$\displaystyle
  \begin{CD}
    \begin{array}{c|cc}
      \omega & a & S \\
      \hline
      a & \alpha & \theta \\
      S & \phi & \Xi
    \end{array}
    @>dS^a>>
    \left(\begin{array}{c|cc}
      \alpha\omega/\sigma_a & a & S \\
      \hline
      a & 1/\alpha & \theta/\alpha \\
      S & -\phi/\alpha & (\alpha\Xi-\phi\theta)/\alpha
    \end{array}\right)_{T_a\to T_a^{-1}}
  \end{CD}
$\hfill\parbox{4in}{Satisfies:
$\green\checkmark$ $R^\pm_{12}\act dS^{1\text{ or }2}=R^\mp_{12}$.
\hfill$\green\checkmark$ $dm^{ab}_c\act dS^c=dS^a\act dS^b\act dm^{ba}_c$.
\newline$\green\checkmark$ $dS^a\act dS^a=I$.
\hfill$\green\checkmark$ $q\Delta^a_{bc}\act dS^b\act dS^c=dS^a\act q\Delta^a_{cb}$.
\newline$\green\checkmark$ Assuming $C_2$, $d\eta^a\act d\epsilon_a=q\Delta^a_{bc}\act dS^c\act dm^{bc}_a$ (also 3 variants).
}

The map (tangle $T$ $\mapsto$ matrix $A$) is anti-multiplicative.
\hfill The MVA mod units:
$L\mapsto(\omega,A) \mapsto \omega\det'(A-I)/(1-T')$\ ${\green\checkmark}$

\vskip -2mm
\rule{\textwidth}{0.5pt}
\vskip -1mm

{\bf Burau.} On $b\in uB_n$, $Bu\colon\sigma_i^{\pm 1}\mapsto U_i^{\pm 1}$.
\hfill{\bf Unitarity.} With $U=Bu(b)$, $\bar{U}\Omega_nU^T=\Omega_n$.

{\bf Thm.} $\Gamma(b)=\begin{array}{c|ccc} 1&s_{b(1)}&s_{b(2)}&\cdots\\ \hline s_1&&&\\ s_2 &&\hspace{-3mm}Bu(b)^T\hspace{-3mm}&\\ \vdots&&& \end{array}$.
\hfill $U_i=\begin{pmatrix} I_i&&& \\ &1-t&t& \\ &1&0& \\ &&&I_{n-i-1}\end{pmatrix}$,
  $U_i^{-1}=\begin{pmatrix} I_i&&& \\ &0&1& \\ &\bar{t}&1-\bar{t}& \\ &&&I_{n-i-1}\end{pmatrix}$,
  $\Omega_n=\begin{pmatrix} 1&0&\cdots&0 \\ 1-t&1&\cdots&0 \\ \vdots&\vdots&\ddots&\vdots \\ 1-t&1-t&\cdots&1 \end{pmatrix}$

\vskip 0mm
\rule{\textwidth}{1pt}

Some matrices:
$\begin{pmatrix} 1-t_i & 1 \\ t_i & 0 \end{pmatrix}$,
$\left(
  \begin{array}{ccc}
    \frac{1}{1-t_1} & 0 & 0 \\
    1 & \frac{1}{1-t_2} & 0 \\
    1 & 1 & \frac{1}{1-t_3} \\
  \end{array}
\right)$,
$\begin{pmatrix} 1-t_j & 1 \\ t_i & 0 \end{pmatrix}$,
$\left(
\begin{array}{ccc}
 -\frac{t_1-1}{t_1} & 0 & 0 \\
 \frac{\left(t_1-1\right) \left(t_2-1\right)}{t_2} & -\frac{t_2-1}{t_2} & 0 \\
 \frac{\left(t_1-1\right) \left(t_3-1\right)}{t_3} & \frac{\left(t_2-1\right)
   \left(t_3-1\right)}{t_3} & -\frac{t_3-1}{t_3} \\
\end{array}
\right)$

\vfill

{\bf To do.}
$\bullet$ Full verification program.
$\bullet$ R1?
$\bullet$ Precise relation with Burau/Gassner.
$\bullet$ Concordance.
$\bullet$ Unitarity.
$\bullet$ Planarity.
$\bullet$ A depth-mirror property for u-objects.
$\bullet$ Mutations?
$\bullet$ Link relations?
$\bullet$ Behaviour of A/MVA under mirror/strand reversal?

\newpage

\textbf{$\beta$-better calculus.}
\hfill Constraints.
$\bullet$ Sum of column $x$ is $(\sigma_x-1)w$.
\quad $\bullet$ $\omega^{k-1}\mid\Lambda^kA$.
\quad $\bullet$ At $T_\ast=1$, $\omega=1$ and $A=0$.

\vskip 1mm  $\displaystyle
  \begin{array}{c|c}\omega_1&H_1\\\hline T_1&A_1\end{array}
  \ast
  \begin{array}{c|c}\omega_2&H_2\\\hline T_2&A_2\end{array}
  \underset{\beta_b}{=}
  \begin{array}{c|cc}
    \omega_1\omega_2 & H_1 & H_2 \\
    \hline
    T_1 & \omega_2A_1 & 0 \\
    T_2 & 0 & \omega_1A_2
  \end{array}
$
\hfill $\displaystyle
  \begin{CD}
    \begin{array}{c|c}
      \omega & H \\
      \hline
      u & \alpha \\
      v & \beta \\
      T & \gamma
    \end{array}
    @>tm^{uv}_w>\beta_b>
    \left(\begin{array}{c|c}
      \omega & H \\
      \hline
      w & \alpha+\beta \\
      T & \gamma
    \end{array}\right)_{T_u,T_v\to T_w}
  \end{CD}
$
\hfill $\displaystyle \rho^\pm_{ux}
  \underset{\beta_b}{=}
  \begin{array}{c|cc}
    1 & x \\
    \hline
    u & T_u^{\pm 1}-1
  \end{array}
$

\vskip 1mm $\displaystyle
  \begin{CD}
    \begin{array}{c|ccc}
      \omega & x & y & H \\
      \hline
      T & \alpha & \beta & \gamma
    \end{array}
    @>{hm^{xy}_z}>\beta_b>
    \begin{array}{c|cc}
      \omega & z & H \\
      \hline
      T & \alpha+\sigma_x\beta & \gamma
    \end{array}
  \end{CD}
$
\hfill $\displaystyle
  \begin{CD}
    \begin{array}{c|cc}
      \omega & x & H \\
      \hline
      u & \alpha & \beta \\
      T & \gamma & \delta
    \end{array}
    @>{tha^{ux}}>\beta_b>
    \begin{array}{c|cc}
      \omega+\alpha & x & H \\
      \hline
      u & \sigma_x\alpha & \sigma_x\beta \\
      T & \gamma & \delta+\frac{\alpha\delta-\gamma\beta}{\omega}
    \end{array}
    =: \begin{array}{c|c}
      \cdot & - \\
      \hline
      \mid & \begin{pmatrix}\sigma_x&0\\0&1\end{pmatrix}\cdot A^{ux}
    \end{array}
  \end{CD}
$

\[
  \begin{CD}
    \begin{array}{c|ccc}
      \omega & a & b & S \\
      \hline
      a & \alpha & \beta & \theta \\
      b & \gamma & \delta & \epsilon \\
      S & \phi & \psi & \Xi
    \end{array}
    @>{m^{ab}_{c}}>\beta_b\ {\green\checkmark}>
    \left(\begin{array}{c|cc}
      \omega+\beta & c & S \\
      \hline
      c & \gamma+\sigma_a\delta+\sigma_b(\alpha+\sigma_a\beta)
          +\frac{\beta\gamma-\alpha\delta}{\omega}
        & \epsilon+\sigma_b\theta+\frac{\beta\epsilon-\delta\theta}{\omega} \\
      S & \phi+\sigma_a\psi+\frac{\beta\phi-\alpha\psi}{\omega}
        & \Xi+\frac{\beta\Xi-\psi\theta}{\omega}
    \end{array}\right)_{T_a,T_b\to T_c}
  \end{CD}
\]

The MVA (mod units):\hfill
$
  n\text{-component }L\mapsto(\sigma,\omega,A)
  \mapsto\omega^{2-n}\det'(A-\omega\diag((\sigma_i-1))/(1-T')
$
\hfill${\green\checkmark}$

\vskip -2mm
\rule{\textwidth}{0.5pt}

Note. $A^{ux}=\begin{pmatrix}
  \alpha & \beta \\
  \gamma & \delta+\frac{\alpha\delta-\gamma\beta}{\omega}
\end{pmatrix}
= \begin{pmatrix}
  \alpha & \beta \\
  \gamma & \frac{(\omega+\alpha)\delta-\gamma\beta}{\omega}
\end{pmatrix}
= \frac{1}{\omega}\left[
  (\omega+\alpha)\begin{pmatrix}
    \alpha & \beta \\ \gamma & \delta
  \end{pmatrix}
  - \begin{pmatrix}\alpha\\\gamma\end{pmatrix}
    \begin{pmatrix}\alpha&\beta\end{pmatrix}
  \right]
  =\frac{1}{\omega}\left[(\omega+a_{ux})A-a_{\ast x}a_{u\ast}\right].
$

\vskip 1mm
{\bf Claim.} $\omega^{k-1}\mid \Lambda^kA$ and $\omega^k\mid \Lambda^{k+1}A$ implies $(\omega+\alpha)^{k-1}\mid \Lambda^kA^{ux}$, with $\alpha=a_{ux}$.

{\bf Proof.} With $\bar{u}\in T^k$ and $\bar{x}\in H^k$, $\omega^k$ divides
$\left|\!\begin{array}{cc} \omega & 0 \\ 0 & a_{\bar{u}\bar{x}}\end{array}\!\right|$
and
$\left|\!\begin{array}{cc} a_{ux} & a_{u\bar{x}} \\ a_{\bar{u}x} & a_{\bar{u}\bar{x}} \end{array}\!\right|$
and hence their sum,
$\left|\!\begin{array}{cc} \omega+\alpha & a_{u\bar{x}} \\ a_{\bar{u}x} & a_{\bar{u}\bar{x}} \end{array}\!\right|=$\linebreak[5]
$(\omega+\alpha)\left|\!\begin{array}{cc} 1 & 0 \\ 0 & a_{\bar{u}\bar{x}}-\frac{1}{\omega+\alpha}a_{\bar{u}x}a_{u\bar{x}} \end{array}\!\right|$
$=\frac{1}{(\omega+\alpha)^{k-1}}\left|(\omega+\alpha)a_{\bar{u}\bar{x}}-a_{\bar{u}x}a_{u\bar{x}}\right|$.
So
$\frac{1}{(\omega+\alpha)^{k-1}} \left|\frac{1}{\omega}\left[(\omega+\alpha)a_{\bar{u}\bar{x}}-a_{\bar{u}x}a_{u\bar{x}}\right]\right|$
is integral. \quad$\Box$

That is, with $A_{\bar{u};\bar{x}}$ denoting minors, if $\omega^{k-1}\mu_{\bar{u};\bar{x}}=A_{\bar{u};\bar{x}}$ and $\omega^k\mu_{u\bar{u};x\bar{x}}=A_{u\bar{u};x\bar{x}}$, then $(\omega+\alpha)^{k-1} (\mu_{\bar{u};\bar{x}}+\mu_{u\bar{u};x\bar{x}}) = A^{ux}_{\bar{u};\bar{x}}$.

\vskip -8pt
\rule{\textwidth}{1pt}

\textbf{$\Lambda$-calculus.} $\Lambda(T;H)=R(T)\otimes\left(\Lambda(T)\otimes\Lambda(H)\right)_=$, with $R(T)$ Laurent polynomials in $\{T_u\}_{u\in T}$.
\hfill$\lambda_1\ast\lambda_2 = \lambda_1(\wedge\otimes\wedge)\lambda_2$

$tm^{uv}_w:\ u,v\to w,\,T_u,T_v\to T_w$
\hfill$hm^{xy}_z:\ x\to z,\, y\to\sigma_xz$
\hfill$tha^{ux}:\lambda\mapsto(1+i_u\otimes i_x)\lambda\act(u\to\sigma_xu)$
\hfill$\rho^\pm_{ux}=1+(T_u^{\pm 1}-1)ux$

\rule{\textwidth}{1pt}

{\bf Relations.} $\bullet$ $\rho^+_{ux}\rho^-_{vy}\act tm^{uv}_w\act
hm^{xy}_z=t\epsilon_w h\epsilon_z$.
\quad$\bullet$
$
  \rho^{s_1}_{ux}\rho^{s_2}_{vy}\rho^{s_2}_{wz}
    \act tm^{vw}_v\act hm^{xy}_x\act tha^{ux}
  = \rho^{s_2}_{vx}\rho^{s_2}_{wz}\rho^{s_1}_{uy}
    \act tm^{vw}_v\act hm^{xy}_x.
$

\end{document}

\endinput

