reductive algebraic group $G$.\
$~$ We now begin with giving bounds for the field of definition of the instability parabolic for various $Sl(2)$-modules.

[\[Sl(2)\]]{} Let $K$ be any field (not neccessarily algebraically closed) if char $p>0$. Let $G=Sl(2,K)$. Let $\rho:Sl(2,K) \rightarrow
 S^N(V)$ be the standard symmetric power representation. Let $N=N_0 + N_1p + N_2p^2 + \cdots + N_tp^t$ be the p-adic expansion of $N$. Then for any non-semistable $K$-rational vector $v \in S^N(V)$, the instability parabolic $P(v)$ of $v$ is defined over $K^{1/p^t}$.

By uniquenes of instability parabolic and Galois descent explained before, we can assume that $K$ is seperably closed. Let $X,Y$ denote the basis for $V$ over $K$. Thus $S^N(V)$ can be identified with the vector space of all degree $N$ homogeneous polynomials in $X$ and $Y$. Let $f=\underset {i+j=N}{\sum} a_{ij}X^iY^j, a_{ij} \in K$ be an unstable vector in $S^n(V)$ for the action of $G$.\
Claim 1: $f$ has a zero of multiplicity greater than $N/2$ on $\mathbb{P}^1_{\bar K}$.\
Proof of claim: Let $\lambda(t)$ be the instability 1-PS of $f$ defined over $\bar K$. Every 1-PS of $Sl(2)$ is conjugate over $\bar K$ to the 1-PS $$\mu(t)= \begin{pmatrix}
         t & 0 \\
         0 & t^{-1}
        \end{pmatrix}$$ Choose $g 