A Present-Moment Singularity in an Eternal Universe: Chronovibration, Time Symmetry, and the Rejection of Linear Time in the Aether Physics Model

This article develops a present-moment Singularity for the Aether Physics Model (APM) within the Quantum Measurement Units (QMU) formalism and applies it to cosmology. In APM, time is not a linear coordinate but a bidirectional chronovibration at the Compton frequency Fq, so all physical processes unfold in an eternal present rather than along a physical timeline. The fundamental statements of the theory are expressed as dimensionless ledger closures at the Aether scale, rather than as mixed-unit differential equations. The central result is that the Aether-scale mass mₐ, the primary force scale Gforce, the quantum length C, the chronovibrational frequency Fq, the distributed electrostatic charge e², the maximum Aether magnetic charge eₐ², and the Aether fine-structure parameter a are locked together by Singularity ledgers such as\1 = mₐ C Fq²Gforce, 1 = e²8 a\, {eₐ²}. identities define a present-moment Singularity: a non-physical algebraic core in which the allowed gravitational and electromagnetic scales of the Quantum Aether are fixed once and for all. Dark matter is then interpreted as a modulation of Aether geometry compatible with these closures, rather than as a new particle species, and its mass scale is constrained by a further Singularity condition involving m₃₌/mₐ, mₐ/mₑ, and eₐ²/e². The paper contrasts this eternal-universe, ledger-based cosmology with Big Bang models that rely on an inaccessible physical past. Observational data such as cosmic microwave background (CMB) anisotropies, high-redshift galaxy populations, and the Hubble tension are reinterpreted as present-moment measurements of Aether structure, rather than as relics of an initial singularity. In this view, the key question is not ``what happened long ago? '' but ``what Aether geometry and ledger structure are being measured now? '' Finally, the article outlines qualitative, QMU-formulated predictions for CMB polarization, gravitational-wave ringdowns, and laboratory torsion experiments. In each case, departures from ideal ledger closure are encoded as small dimensionless deviations of the form = X/Y - 1, where X and Y are QMU combinations associated with the Aether unit. These deviations provide concrete opportunities for testing whether the universe is best described by a historical Big Bang singularity or by an algebraic Singularity that is continuously realized in the present. The goal is not to discard existing observational work, but to reframe it in an eternal-universe picture grounded in Aether geometry, chronovibration, and QMU ledgers.