Remarks on Duffin-Kemmer-Petiau theory and gauge invariance

TL;DR

This paper clarifies issues in Duffin-Kemmer-Petiau (DKP) theory related to gauge invariance and electromagnetic coupling, showing that apparent problems vanish when physical components are properly analyzed.

Contribution

The paper demonstrates that the perceived anomalies in DKP theory are resolved through correct analysis of its physical components, clarifying gauge invariance issues.

Findings

Anomalous term in DKP Hamiltonian is not problematic when physical components are considered.

Differences between DKP and Klein-Gordon interaction terms are due to misinterpretation.

Proper gauge analysis shows DKP theory maintains gauge invariance.

Abstract

Two problems relative to the electromagnetic coupling of Duffin-Kemmer-Petiau (DKP) theory are discussed: the presence of an anomalous term in the Hamiltonian form of the theory and the apparent difference between the Interaction terms in DKP and Klein-Gordon (KG) Lagrangians. For this, we first discuss the behavior of DKP field and its physical components under gauge transformations. From this analysis, we can show that these problems simply do not exist if one correctly analyses the physical components of DKP field.