The Universal Spectral Function and Observer-Curated Realities: How Perception Filters the Geometry of the Cosmos

In Sixta Theory, reality is not a single, fixed structure but a filtered harmonic projection curated by each observer. This paper introduces the Universal Spectral Function F[Φ,Θ,χ], a total harmonic field encoding all possible configurations of space-time, and describes how individual observers extract a filtered version of this universal geometry through trust vector alignment. We present the formal structure of observer-curated reality and explore the implications for measurement, agreement, and the nature of perceived space-time.