Encryptment, Time Travel, and Musical Traces: A Speculative Complement to Thermodynamic Memory Erasure on Closed Timelike Curves

Recent work has sharpened the conflict between time travel to the past and the persistence of memory. Carlo Rovelli has argued that along closed timelike curves (CTCs), the thermodynamic arrow of time cannot globally align with an observer’s sense of “past → future,” undermining the naive image of visiting one’s own past with intact, forward-pointing memories. Lorenzo Gavassino has gone further: for a quantum system whose worldline is a CTC generated by a periodic isometry, the internal dynamics are constrained so that, after one loop, the system must return to its initial microstate. This implies spontaneous memory erasure and the absence of time-travel paradoxes within that class of CTCs. In this note, I outline a speculative framework—the Encryptment Thesis (ET)—in which some aspects of “lost” memories can be externally encoded into robust physical structures, such as music, in a way that survives time-travel–induced amnesia in topologically nontrivial CTC geometries of the kind I call the Butterfly Tongue, Chronotunnel, Jump-Rope, and Yo-Yo time machines. These metrics appeared to me not as deliberately engineered solutions, but as visions or memories that were subsequently analyzed and shown to support CTCs and closed timelike lines (CTLs) that appear non-paradoxical because of their global topology and identity recursion. The acronym ET is deliberate: it alludes both to Encryptment Thesis and to “extraterrestrial,” reflecting the intuition that such time machines function, in practice, like alien technology—physically subtle, topologically rich, and far beyond current engineering. Within this ET framework, musical works (for example, Mozart’s symphonies, or extended improvisations such as the Grateful Dead’s Dark Star on Live/Dead) are modeled as high-dimensional “codewords” that can carry identity-dependent, subverbal information across time-travel loops. They can later act as Proustian keys that partially restore memories after a phase of amnesia. The goal is not to challenge the mathematical correctness of Rovelli’s and Gavassino’s CTC analyses, but to extend the conceptual landscape by (i) distinguishing between simple, globally periodic CTCs and more topologically intricate CTC spacetimes, and (ii) exploring how Rovelli’s thermodynamic account of memory as physical trace could coexist with an “encrypted, distributed” view of identity and recall.