We propose the resource theory of a special antiunitary asymmetry in quantum theory. The notion of antiunitary asymmetry, in particular,
PT-asymmetry is different from the usual resource theory for asymmetry about unitary representation of a symmetry group, as the
PT operator is an antiunitary operator with
P being any self-inverse unitary and
T being the time-reversal operations. Here, we introduce the
PT-symmetric states,
PT-covariant operations and
PT-asymmetry measures. For single qubit system, we find duality relations between the
PT-asymmetry measures and the coherence. Moreover, for two-qubit states we prove the duality relations between the
PT-asymmetry measures and entanglement measure such as the concurrence. This gives a resource theoretic interpretation to the concurrence which is lacking till today. Thus, the
PT-asymmetry measure and entanglement can be viewed as two sides of an underlying resource. Finally, the
PT-symmetric dynamics is discussed and some open questions are addressed.