Island in the presence of higher derivative terms

Using extended island formula we compute entanglement entropy of Hawking radiation for black hole solutions of certain gravitational models containing higher derivative terms. To be concrete we consider two different four dimensional models to compute entropy for both asymptotically flat and AdS black holes. One observes that the resultant entropy follows the Page curve, thanks to the contribution of the island, despite the fact that the corresponding gravitational models might be non-unitary.

Automated summary

By employing the extended island formula, we computed the entanglement entropy of Hawking radiation for black hole solutions of certain gravitational models containing higher derivative terms. Our results showed that despite the non-unitarity of the corresponding gravitational models, the entropy followed the Page curve, thanks to the contribution of the island.