Two-body Dirac equation in DSR: results for fermion-antifermion pairs

TL;DR

This paper develops a modified two-body Dirac equation within doubly special relativity (DSR), analyzing fermion-antifermion pairs and revealing DSR-induced shifts in binding energies, especially at large distances and high energies.

Contribution

It introduces the first DSR-modified two-body Dirac equation and explores its implications for fermion-antifermion systems, including energy-dependent fine-structure constant and binding energy shifts.

Findings

DSR modifications become significant at large distances.

Binding energy levels are shifted due to DSR effects.

The effective fine-structure constant varies with energy as ff(E)/lpha \u2248 1 - E/(4E_p).

Abstract

This study investigates a modified two-body Dirac equation in (2+1)-dimensional spacetime, inspired by Amelino-Camelia's doubly special relativity (DSR). We begin by deriving a covariant two-body Dirac equation that, in the absence of DSR modifications, reduces to a Bessel-type wave equation. Incorporating corrections from the chosen DSR model modifies this wave equation, yielding solutions consistent with established results in the low-energy regime. We demonstrate that the effects of DSR modifications become particularly pronounced at large relative distances. For a coupled fermion-antifermion pair, we derive the modified binding energy solutions. By accounting for first-order Planck-scale corrections, we show that the fine-structure constant \alpha behaves as an energy-dependent running parameter, given by \(\alpha_{eff(E)}/\alpha \approx 1 - \frac{E}{4E_p}\), where E_p is the Planck energy. Binding energy levels are computed using a first-order approximation of the DSR modifications, and the results are applied to positronium-like systems. Our model reveals that DSR modifications induce shifts in the binding energy levels. To the best of our knowledge, DSR-modified two-body equations have not been previously studied. This model is the first of its kind, opening new avenues for further research in this area.