Ecosystem for Closed Timelike Curves: An Energy Conditions Perspective

Abstract

In this article, we explore the relationship between the existence of closed timelike curves and energy conditions that occur in the Kerr-Newman spacetime. To quantify the dependence, we define a correlation index between energy conditions and closed timelike curves. Based on the inputs from Hawking's chronology protection conjecture, we analyze two popular variants of Kerr-Newman spacetime: Non-commutative and Rastall Kerr-Newman spacetimes. These two models provide complementary scenarios that aid in analyzing Hawking's statements regarding the correlation of closed timelike curves and energy conditions from a local and a global perspective. We report the results outlining the possible role played by violations of energy conditions in eliminating the closed timelike curves in two contrasting situations, namely in spacetimes with and without curvature singularities.