  In this paper, we conduct a comprehensive exploration of the relativistic
quantum dynamics of spin-0 scalar particles, as described by the
Duffin-Kemmer-Petiau (DKP) equation, within the framework of a magnetic
space-time. Our focus is on the Bonnor-Melvin-Lambda (BML) solution, a
four-dimensional magnetic universe characterized by a magnetic field that
varies with axial distance. To initiate this investigation, we derive the
radial equation using a suitable wave function ansatz and subsequently employ
special functions to solve it. Furthermore, we extend our analysis to include
Duffin-Kemmer-Petiau oscillator fields within the same BML space-time
background. We derive the corresponding radial equation and solve it using
special functions. Significantly, our results show that the geometry's topology
and the cosmological constant (both are related with the magnetic field
strength) influences the eigenvalue solution of spin-0 DKP fields and
DKP-oscillator fields, leading to substantial modifications in the overall
outcomes
