In this paper, we provide a self-contained investigation of the Weyl double
copy in the Newman-Penrose formalism. We examine the Weyl double copy
constraints for the general asymptotically flat solution in the Newman-Unit
gauge. We find that two transparent solutions of the asymptotic Weyl double
copy constraints lead to truncated solutions for both linearized and Einstein
gravity theory where the solutions are in the manifest form of Petrov type N or
type D in the Newman-Unit gauge.

Introduction

In this paper, we explore the concept of the Weyl double copy in the Newman-Penrose formalism. We specifically investigate the Weyl double copy constraints for the general asymptotically flat solution in the Newman-Unit gauge. By examining these constraints, we are able to derive truncated solutions for both linearized and Einstein gravity theory.

Background

The Weyl double copy is a mathematical technique that allows for the construction of new solutions in gravitational theories by relating them to corresponding solutions in gauge theories. This concept has been of great interest in recent theoretical physics research as it offers new insights and connections between different areas of study.

The Newman-Penrose formalism, on the other hand, provides a powerful framework for understanding gravitational fields through a set of complex null tetrad variables. By applying this formalism, we can analyze and express gravitational solutions in a more comprehensible manner.

Research Methodology

We begin our investigation by considering the general asymptotically flat solution within the Newman-Unit gauge. By imposing the Weyl double copy constraints, we explore various possibilities for constructing solutions that satisfy these constraints.

We utilize mathematical techniques and equations within the Newman-Penrose framework to derive solutions that correspond to truncated forms of both linearized and Einstein gravity theories. Our focus is on solutions that manifest in the form of Petrov type N or type D within the Newman-Unit gauge.

Findings

Our analysis reveals two distinct transparent solutions that satisfy the asymptotic Weyl double copy constraints. These solutions correspond to truncated forms of both linearized and Einstein gravity theories. Importantly, these solutions exhibit a manifest form of Petrov type N or type D when expressed within the Newman-Unit gauge.

Roadmap for Future Research

While this study provides valuable insights into the Weyl double copy in the Newman-Penrose formalism, there are several avenues for further investigation:

  • Exploration of additional gauge choices: The investigation could be extended to explore the Weyl double copy constraints within alternative gauge choices, potentially revealing new solutions and connections.
  • Generalization to other gravitational theories: It would be interesting to apply the Weyl double copy technique to other gravitational theories beyond linearized and Einstein gravity, such as modified gravity theories.
  • Quantum gravity implications: Investigating the implications of the Weyl double copy in the context of quantum gravity theories may provide novel insights into the relation between gravity and other fundamental forces.

Conclusion

This study has demonstrated the power of the Weyl double copy in the Newman-Penrose formalism for deriving truncated solutions in both linearized and Einstein gravity theories. The manifest Petrov types N and D within the Newman-Unit gauge offer a tangible connection between gravitational and gauge theories. Further research opportunities exist in exploring different gauge choices, generalizing to other gravitational theories, and investigating quantum gravity implications.

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