Well, there are neutron stars that are functionally one giant unstable element held together by gravity instead of the strong force. The only reason they don't collapse further is because of neutron degeneracy pressure. Considering the relationship between half life and atomic size, coupled with the longevity of neutron stars, i'd say so, but it's a bit of a stretch.
Edit. For a less extreme condition where the nucleus is not so massive as to be stabilized by gravity, it seems that certain types of decay, like electron capture decay, vary with pressure, while others like ß emission does not.
Phalcone42 t1_itxr3al wrote
Reply to Would heavy unstable elements at the core of a star have a significantly extended half-life due to gravity? by SpectralMagic
Well, there are neutron stars that are functionally one giant unstable element held together by gravity instead of the strong force. The only reason they don't collapse further is because of neutron degeneracy pressure. Considering the relationship between half life and atomic size, coupled with the longevity of neutron stars, i'd say so, but it's a bit of a stretch.
Edit. For a less extreme condition where the nucleus is not so massive as to be stabilized by gravity, it seems that certain types of decay, like electron capture decay, vary with pressure, while others like ß emission does not.