• Inertial Frame Dragging and Relative Rotation of ZAMOs in Axistationary Asymptotically Flat Spacetimes 

      Bræck, Simen (Universe;, Peer reviewed; Journal article, 2023)
      In axistationary, asymptotically flat spacetimes, zero angular momentum observers (ZAMOs) define an absolute standard of non-rotation locally, as can be verified by the absence of any Sagnac effect for these observers. ...
    • A physical interpretation of Hubble’s law and the cosmological redshift from the perspective of a static observer 

      Bræck, Simen; Elgarøy, Øystein (General Relativity and Gravitation;44 (10), Journal article; Peer reviewed, 2012-07-18)
      We derive explicit and exact expressions for the physical velocity of a free particle comoving with the Hubble flow as measured by a static observer, and for the frequency shift of light emitted by a comoving source and ...
    • Relativistic dynamics for hydrogenlike systems 

      Kjellsson, Tor; Selstø, Sølve; Bræck, Simen; Lindroth, Eva (Peer reviewed; Journal article, 2015)
      The interaction between super intense laser pulses and hydrogenlike systems is investigated. We aim to study cases where the field drives the electron up to velocities of v~0.5c, where relativistic effects are believed to ...
    • The Cosmic Causal Mass 

      Bræck, Simen; Grøn, Øyvind; Farup, Ivar (Journal article; Peer reviewed, 2017)
      In order to provide a better understanding of rotating universe models, and in particular the Gödel universe, we discuss the relationship between cosmic rotation and perfect inertial dragging. In this connection, the concept ...