An honest tech tree for civilization · 20 bottleneck technologies
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20 hard problems, grouped by the fields working on them. Scroll the list — nothing is cut.Grouped for browsing; ordering within each domain is editorial, not a ranking.
Intelligence & Machines
5AGI
AI can already help with many kinds of thinking, but it still makes confident mistakes and struggles to carry a big job through on its own.Frontier models saturate most static benchmarks, yet reliable long-horizon autonomy, calibrated reasoning and a shared definition of general intelligence all remain open - so any single 'percent to AGI' is a guess dressed as a number.
Brain Connectomics
Researchers have mapped a whole fly brain and a tiny piece of mouse brain. The hard part is scaling that detail across an entire mammal without losing or inventing connections.A whole adult fly is mapped at synapse resolution and a mouse cortical fragment now contains more than half a billion detected synapses; the whole mouse remains an estimated three orders of magnitude larger.
DNA Data Storage
DNA can hold computer files in an extraordinarily small sample. The missing step is a useful machine that writes a large archive quickly, finds one file and costs less than today's cold storage.Synthetic DNA has recovered a 200 MB random-access archive without bit errors and automated a complete write-to-read cycle for five bytes, but no public benchmark joins useful payload, throughput, retrieval and cost.
Fault-Tolerant Quantum
Today's quantum computers are too error-prone to trust. Fixing that means going from a handful of good qubits to millions.Error-corrected qubits have crossed below threshold; the open question is scaling from one logical qubit to the millions a useful machine needs.
General Robotics
Robots can walk, run and keep their balance beautifully now. The hard part left is hands and judgment: doing varied tasks all day, safely, without a human quietly steering.Legged locomotion is essentially solved, but dexterous manipulation and open-world autonomy are not, so today's factory and home robots run narrow, supervised, and heavily teleoperated.
Earth & Space
5Cheap Space Launch
Rockets can now land and fly again, which made space far cheaper - but the truly cheap ticket needs a whole rocket you can reuse in days, and nobody has that yet.Reusable first stages have cut the price of orbit by more than 90% since the Shuttle, but the sub-$100/kg goal depends on rapid full reuse that Starship has not yet demonstrated.
Closed-Loop Life Support
The space station recycles almost all its water, but a self-sustaining habitat still has to close air, food and waste loops at the same time.Water recycling is near exploration grade in orbit, but oxygen, food, waste and maintenance have never been closed together beyond Earth.
Direct Air Capture
Machines can already pull carbon from the sky. The challenge is doing it cheaply - and a million times bigger.Plants that pull CO2 straight from the air are running; the open question is cost per tonne and scaling from thousands to billions of tonnes.
Exoplanet Biosignatures
We know more than 6,000 planets beyond our Solar System, but zero confirmed living ones. The next leap needs a telescope that can separate an Earth-like planet from a star ten billion times brighter.Atmospheric spectroscopy is now routine for some large exoplanets, but no world beyond Earth has yielded a confirmed biosignature; the observatory intended to survey nearby potentially habitable worlds remains in development.
Planetary Defense
We have moved one harmless asteroid. The bigger gap is seeing a dangerous one early enough: more than half of the estimated regional-size population is still unknown.Humanity has demonstrated one asteroid-deflection technique, but the survey needed to find regional-scale threats is only halfway to its statutory goal.
Energy
4Clean Hydrogen
Clean hydrogen could fuel steel, ships, and fertilizer. First it has to get cheap - and get built at scale.Electrolysis works; the open question is whether clean hydrogen can reach a few dollars a kilogram and scale to industrial volumes.
Electrochemical Ammonia
Small cells can now make ammonia from nitrogen reliably for days, but they are still far too slow and energy-hungry to replace an ammonia plant.Verified lithium-mediated cells now combine high selectivity with continuous operation, but no system has simultaneously demonstrated industrial current density, energy efficiency, scale and lifetime.
Enhanced geothermal
Hot rock is everywhere underground. The race is to build the plumbing to reach it - cheaply, safely, and at the scale of a real power plant.The physics of engineered reservoirs is proven; the open question is whether they can be drilled cheaply, run for years, and financed at utility scale.
Nuclear Fusion
We have made a tiny star flash in a laboratory; now we have to turn that flash into a dependable power station.Fusion has crossed scientific breakeven, but an economical power plant still requires a much harder engineering breakeven.
Biology & Health
4100-Day Vaccines
COVID took 326 days. The target for the next pandemic is 100 - a vaccine before the outbreak spirals.COVID compressed vaccine development from years to months; the goal is a repeatable 100 days from a new pathogen to authorized shots.
Healthy Longevity
We can slow parts of aging in animals; proving that people gain many healthy years will take long, careful trials that are only just starting.Multiple interventions now reproducibly slow aging in mice, but no treatment has yet shown a large, durable extension of healthy lifespan in humans.
Speech BCI
Electrodes read the brain's signals for speech. The race is to make them fast, accurate, and durable enough for daily life.Implanted electrodes can already turn neural activity into words on a screen; the open questions are speed, vocabulary, and whether it lasts for years.
Xenotransplant
Thousands die waiting for organs. Gene-edited pig kidneys and hearts could close the gap - if they last.Gene-edited pig organs have kept people alive for months; the open question is whether they can replace human donors for years, not weeks.
Materials
2Near-Zero Cement
Making cement pumps out huge amounts of CO2. New recipes and capture can slash it - if they stay cheap enough to use everywhere.Cement is about 8% of global CO2; low-clinker chemistries and carbon capture can cut it deeply, but not yet at commodity cost and scale.
Room-temp Superconductors
Materials squeezed to crushing pressures lose resistance when nearly warm, but nothing verified works in an ordinary room - and the loudest recent claims turned out to be wrong.Superconductivity near room temperature has only been credibly observed under megabar pressures; every ambient-pressure room-temperature claim has failed replication or been retracted.
The whole tree · figure 1 of 2 · the approachfigure 1 of 2
Distance from the centre is the answerThe closer to the middle, the closer to real
Rings are maturity stages; sectors are fields. The bullseye is deployment, and it is honestly empty. Select a problem to light its direct dependencies.Everything heads toward the middle. Nothing has landed yet — tap a problem to see what it needs and what it opens.
The whole tree · figure 2 of 2 · the interchangefigure 2 of 2
Five lines, one unbuilt terminusFive lines, all heading for the same station
Each field is a transit line running through maturity zones. Dashed transfers are dependencies; every final stretch into Deployed is unbuilt track.Read it like a subway map. Every colour is a field; the part where it actually arrives has not been built yet.