Holography in the Penrose limit of AdS space

We discuss the Penrose limit of pure AdS space, which is flat Minkowski space. Even though there is no holographic principle, we construct a “holographic screen” on which information on the corresponding CFT is encoded. The screen is obtained as a gauge-fixing condition upon restricting the Hilbert space to the states that are annihilated by the generator of scale transformations. This constraint leads to Dirac brackets which turn the Poincaré algebra into the algebra of the conformal group on the “holographic screen”.