<b>The Disintegration Barrier and Its Implications for High-Velocity and FTL Travel</b>

This brief introduces and formalizes the concept of the Disintegration Barrier — the velocity-density limit where spacecraft or physical bodies moving through a particulate medium undergo catastrophic structural failure due to sustained impact energy. It derives the relationship between velocity, local particle density, and energy flux, demonstrating that both luminal and faster-than-light travel are mechanically impossible under any realistic conditions. Field-based shielding and speculative warp mechanisms are also shown to exacerbate rather than mitigate the problem. The paper concludes that overcoming this fundamental barrier would require unknown or non-existent environmental conditions or new physical mechanisms.