标题： 威格纳粒子的天体分解 显示英文标题

标题： Celestial decomposition of Wigner's particles

摘要： 我们提供了威格纳粒子的详细分解，这些粒子被定义为庞加莱群的不可约酉表示，以该群的洛伦兹子群的酉表示形式表示。 正如我们之前指出的，这种分解仅涉及属于主连续系列的洛伦兹表示，并进一步支持了在天体全息理论背景下讨论的散射振幅与共形关联函数之间的联系。 我们提供了任意质量以及（半）整数自旋粒子的分解的非常明确的公式，以及任何时空维度的情况。 我们强调，这种分解是唯一的，并且对应希尔伯特空间上具有特定内积。 我们还确认，单位平移仅在主连续系列内的洛伦兹表示之间混合，这是必需的。 指出了对天体全息理论计划的含义。 显示英文摘要

摘要： We provide a detailed decomposition of Wigner's particles, defined as unitary irreducible representations of the Poincar\'e group, in terms of unitary representations of its Lorentz subgroup. As pointed out before us, this decomposition only involves Lorentz representations belonging to the principal continuous series, and further underpins the connection between scattering amplitudes and conformal correlation functions discussed in the context of celestial holography. We provide very explicit formulae for the decomposition of particles of arbitrary mass and (half-)integer spin and for any spacetime dimension. We emphasise that this decomposition is unique and comes with a specific inner product on the corresponding Hilbert space. We also confirm that unitary translations mix Lorentz representations within the principal continuous series only, as required. Implications to the celestial holography program are indicated.