howclose.to

An honest tech tree for civilization · 14 bottleneck technologies

howclose.to

How close are we? — tracked by milestone, metric and setback. Never a fake percentage.

EST. 2026 · UPDATED JULY 2026

The example · Nuclear Fusion · Can we bottle a star?How close are we to fusion power?

19201920Eddington proposes stellar fusion1934Fusion achieved in a lab1958The tokamak is born1968T-3 stuns the field1983JET switches on1991First controlled fusion power1997JET record: Q = 0.672006ITER agreement signed2021Private fusion waveDEC 2022 — HERENIF achieves ignition2027SPARC targets Q > 10~2035ARC — first electricityTODAY · 2026UNLOCKS →Endless clean powerFresh water anywhereReal climate repair
The example · Nuclear Fusion · Can we bottle a star?How close are we to fusion power?Open the Nuclear Fusion file → howclose.to/problems/nuclear-fusion

The recordThe scoreboard

14 tracked

Every number is an editorial judgment with a named next test.No hype. Every bar tells you the next real-world test.

Nuclear Fusion
Energy · Engineering · accelerating
40%TO Engineering breakevenMake the whole power station pay back its energy
AGI
Intelligence · Engineering · accelerating
62%TO Broad cognitive competenceLearn many different kinds of work
General Robotics
Labor · Lab demo · accelerating
30%TO Dexterous manipulationHandle unfamiliar objects and tools
Cheap Space Launch
Space · Scaling · accelerating
35%TO Rapid full reuseReuse the whole rocket, fast
Healthy Longevity
Biology · Lab demo · steady
30%TO Validated aging biomarkersMeasure aging before decades pass
Room-temp Superconductors
Materials · Lab demo · stalled
65%TO Superconductivity above 0°C at any pressureBeat the freezing point of water, even inside a vise
Clean Hydrogen
Energy · Scaling · accelerating
40%TO Ten-gigawatt installed baseBuild the first 10 GW
Direct Air Capture
Climate · Scaling · accelerating
55%TO Hundred-Thousand-Tonne PlantMove beyond small plants
Enhanced geothermal
Energy · Engineering · accelerating
75%TO Repeatable fast drillingDrill many wells quickly
Fault-Tolerant Quantum
Compute · Lab demo · accelerating
35%TO Integrated Universal Logical OperationsCompute while correcting
Near-Zero Cement
Materials · Scaling · steady
35%TO Drop-In Alternative BinderReplace the kiln chemistry
100-Day Vaccines
Biology · Engineering · steady
55%TO Response-Ready Prototype LibraryPrepare before the outbreak
Speech BCI
Biology · Engineering · accelerating
60%TO Real-time expressive voiceRestore a natural voice
Xenotransplant
Biology · Engineering · accelerating
74%TO Sustain one dialysis-free yearLast a full year
FEATURED · NUCLEAR FUSION
Milestone path1958First tokamakThe Soviet T-1 begins the tokamak line ofmagnetic-confinement experiments.1997JET reaches Q=0.67JET sets a long-standing magnetic-fusion gainrecord.WE ARE HEREDec 2022NIF ignitionA laser-driven target releases 3.15 MJ from2.05 MJ delivered to the capsule.~2027SPARC eng. breakeven attemptSPARC targets plasma gain Q>10 in a compacthigh-field tokamak.2030sARC first grid powerA proposed pilot plant aims to turn sustainedfusion into electricity.
FIG. 0 The road to fusion power — filled stops are history, open stops are scheduled attempts.
Scientific ignitionGet more energy out of the fuel than we shine in '22Engineering breakevenMake the whole power station pay back its energy 40%Grid economicsMake fusion cheap enough for the grid 12%
Read the fusion analysis →
FIGURE 1 · THE DEPENDENCY GRAPHWHAT UNLOCKS WHAT

What unlocks whatEvery breakthrough opens a door

A research map of the bottleneck technologies that move civilization forward.See the breakthroughs that have to happen before the future gets easier.

Technology dependency treeA left-to-right figure showing which technology breakthroughs depend on others.AGIEngineering · 62%Cheap Space LaunchScaling · 35%Enhanced geothermalEngineering · 75%Fault-Tolerant QuantumLab demo · 35%Room-temp SuperconductorsLab demo · 65%XenotransplantEngineering · 74%Clean HydrogenScaling · 40%Direct Air CaptureScaling · 55%General RoboticsLab demo · 30%Healthy LongevityLab demo · 30%Nuclear FusionEngineering · 40%100-Day VaccinesEngineering · 55%Speech BCIEngineering · 60%Accelerated science everywhereUnlocksCheap satellite mega-constellationsUnlocksFirm clean power almost anywhereUnlocksPredictive quantum chemistryUnlocksLossless power gridsUnlocksAn expandable organ supplyUnlocksNear-Zero CementScaling · 35%Low-emissions fertilizerUnlocksNeutralize residual emissionsUnlocksSafer dangerous workUnlocksCompressed morbidityUnlocksEndless clean powerUnlocksOutbreak containment before global spreadUnlocksRestored conversation after paralysisUnlocksLower-carbon urbanizationUnlocks
● In progress · ○ Awaiting breakthrough · — — Dependency