2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/182974We consider string theory on the Lorentzian Melvin geometry, which is obtained by analytically continuing the two-parameter Euclidean Melvin background. Because this model provides a solvable conformal field theory that describes time-dependent twisted string dynamics, we study the string one-loop partition function and the D-brane spectrum. We found that both the wrapping D2-brane and the codimension-one D-string emit winding strings, and this behavior can be traced to the modified open string Hamiltonian on these probe D-branes.13 pages, v2,v3,v4: changes and references added, v5: final version in PTPHigh Energy Physics - Theorytext