This paper proposes a two part reinterpretation of cosmological redshift and spectral line broadening, based on classical wave behavior rather than spacetime expansion.First: Redshift arises from the medium itself. Light does not travel through a vacuum. Intergalactic space is filled with tenuous plasma that interacts more readily with higher frequencies. As light travels across vast distances, high frequency components are scattered or absorbed more often than lower ones. What reaches us is biased toward longer wavelengths. This is survivorship, not metric expansion.Second: Coherence loss is a direct result of geometry in three dimensions. As wavefronts expand, their surface area grows, and each observer samples a smaller portion of the full wave. If the emitter has any instability in frequency, timing, or angle, this leads to phase variation across the observed wave. The result is line broadening and signal smearing. These effects do not require stretching of space or time. They are a natural outcome of how expanding waves behave in a structured field.Together, these effects explain the two most persistent cosmological signatures, redshift and time dilation, without invoking expansion at all. Light doesn’t just stretch. It is filtered and smeared.