<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mi mathvariant="double-struck">T</mml:mi></mml:mrow></mml:math> Operator Bounds on Angle-Integrated Absorption and Thermal Radiation for Arbitrary Objects

We derive fundamental per-channel bounds on angle-integrated absorption and thermal radiation for arbitrarily structured bodies---for any given material susceptibility and bounding region---that simultaneously encode both the per-volume limit on polarization set by passivity and geometric constraints on radiative efficiencies set by finite object sizes through the scattering \mathbb{T}operator. We then analyze these bounds in two practical...