collaborators

7 papers

gr-qc2026

Boson Stars surrounded by Polish Doughnuts in Scalar-Tensor Theory

Kristian Gjorgjieski, Maxim Rose, Burkhard Kleihaus +2

We investigate thick accretion disks (Polish Doughnuts) around rotating self-interacting boson stars in general relativity and scalar-tensor theories, focusing on spontaneously sca…

gr-qc2026

Polarized Equatorial Emission around Kerr Black Holes with Synchronized Scalar Hair. I. Direct images

Valentin O. Deliyski, Galin N. Gyulchev, Daniela D. Doneva +2

We investigate the polarization properties of the direct images of a geometrically and optically thin accretion disk around fully self-consistent models of rotating Kerr black hole…

gr-qc2026

Images of the Thin Accretion Disk Around Kerr Black Holes coupled to time periodic scalar fields

Galin N. Gyulchev, Daniela D. Doneva, Valentin O. Deliyski +2

We investigate the orbital structure and observable appearance of rotating Kerr black holes endowed with synchronized scalar hair described by two time-periodic scalar fields with…

gr-qc2025

Shadows of rotating traversable wormholes surrounded by plasma

Tsanimir Angelov, Rasim Bekir, Galin Gyulchev +2

We study the influence of the plasma environment on the shadows of stationary axisymmetric wormholes. We consider a sample of several wormhole solutions and plasma distributions fo…

gr-qc2025

Matter Accumulations and Accretion Tori around Wormholes

Kristian Gjorgjieski, Jutta Kunz, Petya Nedkova

We study circular orbits and accretion structures around symmetric wormholes. As exemplary solutions we choose three different wormhole spacetimes, namely rotating traversable worm…

gr-qc2025

Circular Orbits and Photon Orbits at Wormhole Throats

Kristian Gjorgjieski, Jutta Kunz, Petya Nedkova

In this work we study timelike circular orbits and photon orbits at the throat of stationary and axisymmetric wormholes. Our minimal requirements on the spacetime are the existence…