diff --git a/main.tex b/main.tex index 5e0cd804394cfe3287a93289a47f6c392c78c011..de1ce3a745c1e352e9e7d42ca09b4d5393cd22e6 100644 --- a/main.tex +++ b/main.tex @@ -169,17 +169,11 @@ surfaces and $\PP^2$. which has the same tilt slope as $v$: $\nu_{\alpha,\beta}(u) = \nu_{\alpha,\beta}(v)$. \noindent - Furthermore the following Bogomolov-Gieseker inequalities are satisfied: + Furthermore the following inequalities are satisfied: \begin{itemize} \item $\Delta(u) \geq 0$ \item $\Delta(v-u) \geq 0$ - \item $\Delta(u) + \Delta(v-u) \leq \Delta(v)$ - \end{itemize} - \noindent - And finally these two conditions are satisfied: - \begin{itemize} - \item $\chern_1^{\beta}(u) \geq 0$ - \item $\chern_1^{\beta}(v-u) \geq 0$ + \item $0 \leq \chern_1^{\beta}(u) \leq \chern_1^{\beta}(v)$ \end{itemize} Note $u$ does not need to be a Chern character of an actual sub-object of some @@ -498,7 +492,7 @@ Fixing attention on the only possible case (2), illustrated in Fig \ref{fig:correct-hyperbol-intersection}. $P$ is on the left of $V_{\pm u}$ (first part of consequence 2), so $u$ must have positive rank (consequence 1) -to ensure that $\chern_1^{\beta{P}} \geq 0$ (since the pseudo-wall passed over +to ensure that $\chern_1^{\beta(P)} \geq 0$ (since the pseudo-wall passed over $P$). Furthermore, $P$ being on the left of $V_u$ implies $\chern_1^{\beta{P}}(u) \geq 0$, @@ -845,85 +839,6 @@ This condition amounts to: d &\geq \beta_{-}q + \frac{1}{2} \beta_{-}^2r \end{align} -\subsubsection{ - \texorpdfstring{ - $\Delta(u,v-u) \geq 0$ - }{ - Δ(u,v-u) ≤ 0 - } -} -\label{subsect-d-bound-bgmlv1} - -Writing the condition in terms of the twisted chern characters -for $u$ and $v$ at $\beta$ -($(r,\chern_1^{\beta}(u),\chern_2^{\beta}(u))$ -and $(R-r,\chern_1^{\beta}(v-u),\chern_2^{\beta}(v-u))$) yields: - -\begin{equation} -\label{eqn:bgmlv1-pt1} - (R-r)\chern_2^{\beta}(u) - \leq - \chern_1^{\beta}(u)\chern_1^{\beta}(v-u) - - r\chern_2^{\beta}(v-u) -\end{equation} - -Which rearranges to (using additivity of $\chern_2^{\beta}$): - -\begin{equation} -\label{eqn:bgmlv1-pt2} - (R-2r)\chern_2^{\beta}(u) - \leq - \chern_1^{\beta}(u)\chern_1^{\beta}(v-u) - - r\chern_2^{\beta}(v) -\end{equation} - -With $u$ satisfying the condition given by equation \ref{eqn-cintermsofm}, -we note that $\chern_1^{\beta}(u),\chern_1^{\beta}(v-u) \geq 0$. - -In the special case with $P=(\beta_{-},0)$, -we have $\chern_2^{\beta_{-}}(v)=0$, and we can assume -equation $\chern_2^{\beta_{-}}(u)>0$ (eqn \ref{eqn:radius-cond-betamin}) -in the context of our problem. - -Finally, $r>0$ as per the statement of the problem, so the right-hand-side -of equation \ref{eqn:bgmlv1-pt1} is always greater than, or equal, to zero. -And so, when $P\coloneqq(\beta_{-},0)$, this condition $\Delta(u,v-u) \geq 0$ is -always satisfied when $2r \geq R$, provided that the other conditions of the -problem statement (\ref{subsect:problem-statement-2}) hold. - -However, when $2r<R$, this condition does add potentially independent condition -of the others: - -\begin{equation} -\label{eqn:bgmlv1-pt3} - \chern_2^{\beta}(u) - \leq - \frac{ - \chern_1^{\beta}(u)\chern_1^{\beta}(v-u) - - r\chern_2^{\beta}(v) - } - {R-2r}, - \qquad - 2r<R -\end{equation} - -Expressed in terms of $d$ and $q$: -\begin{equation} -\label{eqn:bgmlv1-pt4} - d - \leq - \beta_{-}q - +\frac{1}{2}{\beta_{-}}^2r - + - \frac{ - q(\chern_1^{\beta}(v)-q) - - r\chern_2^{\beta}(v) - } - {R-2r}, - \qquad - 2r<R -\end{equation} - \subsubsection{ \texorpdfstring{ $\Delta(E) \geq 0$ @@ -1203,17 +1118,6 @@ vertical wall (TODO as discussed in ref). \phantom{+}& % to keep terms aligned &\qquad\text{when\:} r > 0 \label{eqn:radiuscond_d_bound_betamin} -\\ - d &\leq& - \frac{1}{2}{\beta}^2r - &+ \beta q - +& - \frac{ - q(\chern_1^{\beta}(v)-q) - } - {R-2r}, - &\qquad\text{when\:} 0 < r < \frac{R}{2} - \label{eqn:bgmlv1_d_bound_betamin} \\ d &\leq& \sage{bgmlv2_d_upperbound_linear_term} @@ -1279,18 +1183,6 @@ def plot_d_bound( ): # Equations to plot imminently representing the bounds on d: - eq1 = ( - ( - beta^2*r/2 - + beta*q - + q*(chb1v - q)/(R-2*r) - ) - .subs(chb1v == v_example.twist(beta_min(v_example)).ch[1]) - .subs(beta = beta_min(v_example)) - .subs(q == q_example) - .subs(R == v_example.ch[0]) - ) - eq2 = ( bgmlv2_d_upperbound .subs(R == v_example.ch[0]) @@ -1337,13 +1229,6 @@ def plot_d_bound( linestyle = "dotted", legend_label=r"lower bound: $\mathrm{ch}_2^{\beta_{-}}(u)>0$" ) - + plot( - eq1, - (r,0,v_example.ch[0]/2), - color='red', - linestyle = "dashed", - legend_label=r"upper bound: $\Delta(u,v) \geq 0$" - ) ) example_bounds_on_d_plot.ymin(ymin) example_bounds_on_d_plot.ymax(ymax)