Mathematicians often express the identity operator using notation like \hat{1} = \int dx |x\rangle \langle x|, which represents the resolution of identity in quantum mechanics. The discussion also mentions the use of projectors in a rigged Hilbert space, denoted as \hat{1} = \int dx \ \hat{P}_{x}. A rigged Hilbert space is described as a set of four spaces, including \Omega, \mathcal{H}, \tilde{\mathcal{H}}, and \tilde{\Omega}. The conversation includes playful banter, indicating a lighthearted exchange among participants. Ultimately, the focus remains on the mathematical notation and concepts relevant to quantum mechanics.