Differentially rotating neutron stars in scalar-tensor theories of gravity

Understand

We present the first numerical models of differentially rotating stars in alternative theories of gravity.

• We chose a particular class of scalar-tensor theories of gravity that is indistinguishable from GR in the weak field regime but can lead to significant deviations when strong fields are considered.
• We show that the maximum mass that a differentially rotating neutron star can sustain increases significantly for scalarized solutions and such stars can reach larger angular momenta.
• In addition, the presence of a nontrivial scalar field has the effect of increasing the required axis ratio for reaching a given value of angular momentum, when compared to a corresponding model of same rest mass in general relativity.