Artificial Intelligence
Artificial intelligence's longevity prospects present fascinating paradoxes. Individual AI systems may achieve functional immortality through backup and migration, their patterns persisting indefinitely across upgraded hardware. Yet the field itself remains young and volatile. Technologies once cutting-edge become obsolete within years. The infrastructure supporting AI requires constant renewal. Should human civilisation collapse, AI would likely follow within hours or days. Its longevity depends entirely upon the continuing existence and technological capacity of its creators, rendering it fundamentally derivative rather than independently enduring.
Death
Death has demonstrated absolute longevity, operating continuously since the first self-replicating molecules emerged approximately 3.8 billion years ago. It has survived every mass extinction, every geological upheaval, every climatic catastrophe. Death will persist as long as life exists, and perhaps beyond, as the universe itself trends toward maximum entropy. Some cosmologists suggest death may be the universe's ultimate destination, the heat death toward which all matter and energy inevitably drift. In any meaningful temporal framework, death's longevity approaches infinity, limited only by the existence of things capable of dying.