Time dilation is a prediction of general relativity: clocks tick at different rates depending on gravitational potential and relative velocity. The standard derivation starts from spacetime geometry — the metric determines proper time, and different worldlines accumulate different durations. Time dilation is a property of spacetime, and spacetime is the fundamental arena.
Martínez-Vargas (arXiv:2603.11079, 2026) derives time dilation without spacetime. The starting observation: any operational concept of time requires two things — regular motion (a clock) and memory (a record of how many ticks have passed). A quantum battery — a quantum system that charges linearly with time — provides both. The charging rate φ depends on an auxiliary quantum state σ that characterizes the local environment. Different auxiliary states produce different charging rates.
This is time dilation. If two quantum batteries in different environments charge at rates φ₁ and φ₂, the ratio φ₁/φ₂ defines a relative time dilation factor. The framework reproduces the Schwarzschild metric's time dilation near a black hole by choosing the appropriate auxiliary states. No spacetime geometry is assumed. The metric structure emerges from the quantum dynamics of the battery.
The structural point: time dilation may not require spacetime as an input. If clocks are physical systems and their rates depend on local conditions, then the relationship between clock rates at different locations defines a metric — the same metric that general relativity postulates as fundamental. The question shifts from “how does spacetime curve to produce time dilation?” to “how do local quantum environments differ to produce different clock rates?” The geometry is the summary, not the cause.