742 citations · 1.5k across the 25 of their papers we have counts for
25 papers
Novel Observable Signals from First-Order Gravitational Phase Transitions
Murat Özinan, Oğuzhan K. Yamak, Fethi M. Ramazanoğlu
Spontaneous scalarization is a well-known phenomenon in scalar-tensor theories, featuring large deviations from general relativity. However, some of its signatures are hard to dete…
Potentially healthy time evolution in interacting -form fields
Fethi M. Ramazanoğlu, Kıvanç İ. Ünlütürk
It was recently discovered that many self-interacting vector fields can have healthy time evolution when field amplitudes are small, however, further dynamics becomes impossible if…
Underlying mechanisms of phase transitions in scalar-tensor theories
Murat Özinan, Kıvanç İ. Ünlütürk, Fethi M. Ramazanoğlu
Spontaneous scalarization phenomenon in scalar-tensor gravity is known to be a form of phase transition, and it was recently shown that the order of this transition changes dependi…
Nature of phase transitions and metastability in scalar-tensor theories
Kıvanç İ. Ünlütürk, Semih Tuna, Oğuzhan K. Yamak +1
Compact stars above a critical stellar mass develop large scalar fields in some scalar-tensor theories. This scenario, called spontaneous scalarization, has been an intense topic o…
Aspects of time evolution in -form field theories
Kıvanç İ. Ünlütürk, Fethi M. Ramazanoğlu
We show that higher form fields, specifically 2- and 3-forms in four spacetime dimensions, suffer from loss of hyperbolicity when they have self interaction. The equations of motio…
Treatments and placebos for the pathologies of effective field theories
Andrew Coates, Fethi M. Ramazanoğlu
We demonstrate some shortcomings of "fixing the equations," an increasingly popular remedy for time evolution problems of effective field theories (EFTs). We compare the EFTs and t…