Reformat last slide with tabular

main.tex

@@ -12,6 +12,8 @@
 \usepackage{ulem}
 \usepackage{xcolor}
 \usepackage{tcolorbox}
+\usepackage{tabularx}
+\usepackage{array}
 
 \usetheme{edmaths}
 \renewcommand\mathfamilydefault{\rmdefault}
@@ -24,6 +26,7 @@
 
 \newcommand\RR{\mathbb{R}}
 \newcommand\CC{\mathbb{C}}
+\newcommand\ZZ{\mathbb{Z}}
 \newcommand\centralcharge{\mathcal{Z}}
 \newcommand\coh{\operatorname{Coh}}
 \newcommand\rank{\operatorname{rk}}
@@ -291,15 +294,19 @@
 \end{frame}
 
 \begin{frame}{Notable Stability Conditions on Plane}
-	\begin{columns}[t,onlytextwidth] % align columns
-		\begin{column}{.49\linewidth}
-			When $\beta = \mu(E)$ \\
+	\begin{tabular}{ m{10cm}|m{10cm} }
+		$\beta = \mu(E)$
+		&
+		$\alpha$ fixed, $\beta \to - \infty$
+	\\ \hline
+		{
 			$\nu_{\alpha, \beta}(E) = + \infty$ so can only be destabilized by
 			$F \hookrightarrow E$ with $\nu_{\alpha, \beta}(F) = + \infty$ too
 			($\beta = \mu(F)$)
-		\end{column}%
-		\hfill%
-		\begin{column}{.49\linewidth}
+		}
+		&
+		{
+			$n \in \ZZ$
 			\begin{align*}
 				\nu_{\alpha, -n}(E) &=
 				\frac{
@@ -317,7 +324,8 @@
 					}
 				}
 			\end{align*}
-			
+			$\rightarrow$ Tends to Gieseker Stability
+			\vfill
 			\begin{tcolorbox}[title=Gieseker Stability]
 				E stable when red. Hilb. poly.
 				\[
@@ -329,8 +337,8 @@
 				(equiv. to lexic. comparison between poly. coeffs)
 				}
 			\end{tcolorbox}
-		\end{column}
-	\end{columns}
+		}
+	\end{tabular}
 \end{frame}
 
 \section{Walls}