What is Life Tree Nexus?
Life Tree Nexus is the central civic and infrastructural system of Sim Eternal City, the floating city framework designed for communities displaced by climate change and urban ageing. It functions simultaneously as a public plaza, a landmark tower, a data archive, and the operational hub of the floating city's self-sustaining infrastructure. Within the broader Sim Eternal City framework, Life Tree Nexus is the life pillar — the counterpart to No Stone Tombstone, which serves as the death-care system. Together, the two form a continuous cycle with the human being at its centre.
The Plaza
The physical heart of Life Tree Nexus is a vast central plaza formed between four cruise ships — each comparable in scale to Queen Mary 2 — arranged in a diamond formation on the ocean. These ships constitute the outer structure of the floating city; the plaza is the space they create between them.
The floor of the plaza is designed as a single, unified Star Bolt shape — a reference to the cast iron anchor plates found on the facades of 19th-century brick buildings across New York, which give the Sim Eternal City project its logo, Stella in Motion. Each arm of the star extends toward one of the four ships, forming the primary axes of public movement. The plaza is not a fixed programme. It is a modular platform: its arms accommodate concerts, sports events, conventions, open markets, and amusement installations — all designed for easy installation and removal. The plaza reinvents itself continuously.
At the centre of the star, where all arms converge, is the circular hub. This is the fixed foundation of Life Tree Nexus — the bolt at the heart of the star.
The Landmark
Rising from the circular hub is the Life Tree Nexus landmark tower — the defining structure of the floating city's skyline and its primary civic institution. The tower operates across three vertical zones.
At ground level, the hub integrates the city's Library, Open Museum, City Hall, and Data Interface into a single continuous space. This is where citizens enter the structure, where Memory Curators work, and where the plaza and tower meet as one architectural form.
Above ground level, the tower ascends through multiple floors of archival and exhibition space. Content deepens as visitors ascend: recent personal histories at the lower levels, older collective records higher up. The experience is designed so that spatial height and historical depth move together.
At the crown, an observation deck offers a 360-degree view of the floating city and the surrounding ocean. It is the highest publicly accessible point of Sim Eternal City, and the culmination of the Open Museum experience.
The Infrastructure
Below the waterline — invisible to citizens, essential to the city — five infrastructure systems sustain the floating city. Their arrangement corresponds directly to the five arms of the Star Bolt plaza above, making the Stella in Motion form the organizing principle of both the visible and invisible city.
The five systems are: Energy, produced through tidal and wave power embedded in the platform underside, combined with solar generation across the upper decks of the four ships, stored as hydrogen for stable supply. Fresh Water, produced through continuous seawater desalination and rainwater collection across the ship surfaces, with full recirculation of used water. Data Management, running three simultaneous streams — city operations, citizen life, and memory archive — integrated and optimised by a single AI system. Waste and Resource Circulation, a closed-loop system in which organic waste becomes biogas, inorganic waste becomes reusable material, and food waste returns to the farming system. And Aquatic Farming, hydroponic and aquaculture systems integrated into the platform underside, producing a significant portion of the city's food supply.
Together, these five systems make the floating city self-sustaining in energy, water, food, and data. The city does not depend on land infrastructure to function.
Memory and Data
The most distinctive function of Life Tree Nexus is its role as an archive of unsynced human data — the personal digital material that existing platforms were never designed to collect or preserve.
In the course of a human life, the vast majority of digital content generated — photographs, videos, messages, recordings — is never made public. It remains on personal devices, unsynchronised across platforms, invisible to any archive. When a person dies, most of it disappears. Life Tree Nexus is designed to recover this material through two collection events connected to the No Stone Tombstone death-care system.
At the first funeral ceremony, those who knew the deceased bring unshared personal data — the photographs never posted, the recordings never shared, the digital fragments of a life lived outside the public record. This is the first collection. Ten years later, when the physical grave transitions to a digital memorial, a second ceremony marks the transfer. A second collection follows.
The data that arrives through this process is processed by AI, which sorts, classifies, and structures it. It then passes to the Data Interface at ground level, where Memory Curators provide the human context that gives it meaning. The result becomes the content of the Library and Open Museum — a continuously growing archive of human life as it was actually lived, not as it was curated for public view.
The People
Memory Curators are elderly citizens of Sim Eternal City who work in partnership with humanoid robot citizens to contextualise incoming data. Their work is conducted primarily through conversation: the robot asks questions, listens, and connects what is said to what is stored; the human provides the contextual knowledge — the recognition of an era, a place, a particular kind of moment — that no algorithm can replicate.
The role is designed to serve two purposes simultaneously. For the archive, it produces irreplaceable human context. For the Memory Curators themselves, it provides daily structure, social connection, physical movement through the city, and a form of contribution that draws directly on the knowledge accumulated over a lifetime. The model addresses urban loneliness and social isolation not through welfare provision but through meaningful civic participation.
The Economy
Life Tree Nexus supports seven revenue streams that collectively sustain the floating city's operations.
Memorial Tourism draws visitors from land cities to experience the Open Museum — the world's only large-scale archive of previously unshared human life data, continuously updated and unlike any conventional museum collection. The Events and Convention Platform makes the Star Bolt plaza available for concerts, sports events, and corporate gatherings, with the ocean setting providing a differentiation no land venue can replicate. The Testbed and Lab City model offers land city companies and research institutions access to the floating city as a living laboratory — the only environment where energy self-sufficiency, water self-sufficiency, circular waste management, AI-assisted archiving, and elderly-robot collaborative labour all operate simultaneously at urban scale.
Digital Legacy Services provide citizens with subscription-based management of their personal digital archives while alive. Content Licensing makes the Life Tree Nexus archive available to universities, research institutions, and media organisations. Aquatic Farming and F&B generates revenue through on-site restaurants, surplus supply to land cities, and farming experience programmes for visitors. The Memory Curator Training Programme exports the elderly-robot collaborative labour model to other cities and care institutions — the first step toward Sim Eternal City becoming not only a city but a replicable urban model.
Life Tree Nexus within Sim Eternal City
Life Tree Nexus is one of two civic pillars in the Sim Eternal City framework. It operates in direct relationship with No Stone Tombstone: the death-care system generates the data that Life Tree Nexus preserves and transforms. What begins as loss — a person, a life, a collection of unshared moments — becomes, through this system, part of a collective archive that outlasts the individual and returns to the community in the form of cultural content, historical record, and living memory.
The full cycle runs continuously. Human life generates data. Death initiates collection. The archive grows. Memory Curators give it context. The Open Museum makes it accessible. Visitors arrive. The economy sustains the city. The city continues to house people whose lives generate more data. Nothing is wasted. Nothing disappears. That is what Life Tree Nexus is built to ensure.
Life Tree Nexus is a component of the Sim Eternal City framework, developed by IWBFD Studios. For the complete framework overview, visit simeternal.city.