The Arrow of Time from Record Irreversibility An Observer-Based Account of Temporal Asymmetry in Cosmology

The fundamental dynamical laws of physics are largely invariant under time reversal, yet all observers experience a pronounced temporal asymmetry: memories refer to the past rather than the future, macroscopic processes are irreversible, and cosmological history unfolds in a single direction. Standard explanations attribute this arrow of time to entropy increase or to special low-entropy initial conditions, particularly in cosmological and gravitational contexts. In this work, we argue that such accounts remain incomplete because they do not identify the physical mechanism responsible for experienced temporal directionality. We propose that the arrow of time arises from the irreversible accumulation and causal dispersal of physical records accessible to observers. A record is defined as any stable physical correlation encoding information about an interaction. We show that cosmological expansion, decoherence, and causal separation jointly guarantee that records proliferate in one temporal direction while rendering their global erasure operationally impossible. Entropy increase emerges as an effective proxy for this process rather than its fundamental cause. This framework derives the experienced arrow of time without postulating a fundamental temporal asymmetry in the underlying laws.