Bruck conjecture for solutions of first-order partial differential equations in Cm
Sujoy Majumder, Nabadwip Sarkar, Debabrata Pramanik
TL;DR
The paper addresses the Brück conjecture for solutions of first-order PDEs in several complex variables by recasting the problem in a multi-variable Nevanlinna framework. It proves rigidity results: if $f$ satisfies $\partial_{z_i}(f)-a=e^{\alpha(z)}(f-a)$ for all $i$ and the pair $f,\partial_{z_i}(f)$ share $a$ CM, then $\alpha$ must be constant, yielding $f(z)=c_1 e^{A(z_1+\cdots+z_m)}+a-\frac{a}{A}$ (and in the $a=0$ case, $f(z)=c_1 e^{A(z_1+\cdots+z_m)}$). The work also establishes a Borel–Carathéodory-type bound in $\mathbb{C}^m$ and analyzes the order and hyper-order of $f$ to relate growth with derivative behavior. Together, these results extend Brück-type uniqueness from one complex variable to higher dimensions under mild growth and sharing hypotheses, contributing to Nevanlinna theory in several complex variables and providing a rigidity phenomenon for entire PDE solutions.
Abstract
In this paper, we study the Brück conjecture \cite{Bruck-1996} by interpreting it through solutions of first-order partial differential equations in several complex variables. Our results show that the Brück conjecture \cite{Bruck-1996} in $\mathbb{C}^m$ holds under certain additional conditions. In pursuit of this objective, we also establish a Borel-Caratheodory theorem in $\mathbb{C}^m$ and derive several fundamental results on the order and hyper-order of entire functions in higher dimensions.
