Modern “evidence of existence” tests physics, not in one silo, but across a working stackthat combines the particle Standard Model, General Relativity, and the ΛCDMcosmological wrapper. Within their intended domains, these components areextraordinarily successful: the particle Standard Model delivers precision predictions fornon-gravitational microphysics; GR describes a dynamical spacetime and is stronglysupported by gravitational-wave observations; and ΛCDM provides an effectiveparameterized fit to multiple cosmological datasets. Yet the same evidence set highlightsenduring structural gaps: gravity is not contained inside the particle Standard Model;cosmology relies on dominant “dark” components not identified within known particleinventories; and the physical status of “vacuum/space” remains treated largely as anabstract stage with rules rather than as an explicitly conditionable medium. This paperframes these strengths and gaps in a way that directly invites a competing unificationposture: SP3 (Space-Phase) theory, which posits that space itself is a physical,conditionable medium with stiffness gradients, coherence limits, and memory(hysteresis/path dependence). Under SP3, many phenomena commonly described asseparate entities or separate sectors (fields, particles, dark components, propagationeffects) are approached as manifestations of a single medium operating under differentconditioning regimes. The comparison is not posed as a matter of philosophicalpreference, but as an engineering-style question: can SP3 match what the standard stackalready matches, while producing discriminating, falsifiable predictions—especially inregimes where ΛCDM depends on unknown components or where “vacuum” behavior isleft conceptually unresolved?