pass 2's no-LLM fallback previously used broken/placeholder formulas: power_density passed an actuator's own intensive W/kg straight through without scaling by vehicle mass, range_fuel multiplied energy_density by a flat unitless constant, and cost_efficiency was a categorical guess. Replaces all three with formulas grounded in each entity's own declared attributes. Actuator and storage mass are sized to what's actually necessary -- enough power to sustain a platform's target_velocity against resistance (or real thrust/accel requirements where already declared, for aircraft/rocket combos), enough energy to reach the domain's own declared range ceiling -- solved as a closed-form 2x2 linear system rather than an invented mass-fraction table. Platform mass uses the geometric mean of its declared range instead of the bare floor, since a category as broad as Road Vehicle (50kg-36,000kg) is closer to log-uniformly distributed than uniformly distributed. cost_efficiency is now real operating cost (energy price x resistance) plus amortized upfront cost (materials cost by medium x lifetime distance), replacing the old flat per-energy-form guess. Also fixes two bugs found while validating the above against real-world reference values: entities whose power source isn't their own carried mass (Human Muscle, Solar Sail) degenerated to zero power; and combos blocked by a domain-specific constraint kept combinations.status stuck at "valid" forever, which silently miscounted them as passing in two repository queries (count_combinations_by_status, get_pipeline_summary) even though the per-domain result row was correctly marked blocked. Adds target_velocity to platforms that had no declared performance requirement at all, and raises OllamaLLMProvider's HTTP timeout (120s to 300s) to match observed real review-call latency. Validated against 4 real-world reference combos (commuter car, bicycle, delivery drone) and a full 2,970-combination domain run (0 pass-2 failures); all 100 existing tests still pass. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Applied Combinatorics
Innovation via Attribute Mixing
This is an experimental repo which uses lists of physical attributes and recombines them to form new objects. These objects are then reviewed for comprehensibility and viability.
Example:
Let's identify some methods of getting from here to there:
- Car
- Airplane
- Train
- Bicycle
- Walking with your legs
- Wheelchair
- Scooter
- Spaceship
- Teleportation or beaming technology
To build object 'car' you must select a power source. Power sources include:
- Gas/Internal Combustion Engine
- Lithium Ion Batteries
- Hydrogen Combustion Engine
- Human pedalling
- Modular Nuclear Reactor
- Coal/steam locomotion
- the Sun via Solar Sail
- Cannonfire Recoil
- Pushed by a friend
Putting together lists 1 and 2 we can create 81 mostly novel forms of transportation, such as trains powered by solar sails or walking powered by tiny cannon recoil. Obviously some of these concepts are not as viable as others. While being pushed by a friend might work for those in a wheelchair, it is too slow for those in a car. Speed is therefore a target metric. Let's list some target metrics:
- Speed
- Cost efficiency
- Availability
- Safety
- Range (by fuel)
- Range (by platform degredation or maintenance)
Using these metrics this experiment intends to sift vaguely reasonable concepts from nonsense. Its shortlist may include concepts that sound bizarre but may be technically plausible. Bicycles, motorcycles, and e-bikes all had their turn. Why not hydrogen-bikes?
Setup
Docker (recommended)
docker compose up web
Then open http://localhost:5000.
Seed the database with the transport example:
docker compose run cli seed transport
Local development
pip install -e ".[dev,web]"
python -m physcom init
python -m physcom seed transport
python -m physcom_web
Then open http://localhost:5000.
Run tests:
python -m pytest tests/ -q
LLM integration (optional)
By default the pipeline uses stub estimation. To enable Gemini:
pip install -e ".[gemini]"
export LLM_PROVIDER=gemini
export GEMINI_API_KEY=your_key_here
# export GEMINI_MODEL=gemini-2.0-flash # optional, this is the default
physcom run urban_commuting --passes 1,2,3,4
Copy .env.example to .env and fill in your key for persistent configuration.
a few notes: the thin atmosphere and the sun are obvious dependencies to the solar sail power source. Dependencies would include things such as scale of force (nuclear reactor vs pedalling obviously has an important force differential) and geographic requirements (walking requires ground and gravity). The project should include on every entity a list of dependencies. The viability tester will need to pull in all of these dependencies to ensure they do not contradict.
Additionally, metrics are expected to be extremely close to full points or none at all. The speed of a person pushing a car is effectively zero in its domain whereas a rocket powered car would easily reach the limits of speed in the domain. The resulting multiplication between metrics to get the viability score will be heavily logarithmic. This is expected and is intended to be a filter to eliminate technically plausible but completely pointless in practice concepts. Metric weights are therefore dependent on domain, which will also need to be defined.
First pass viability is physics such as force output, possibly generalized by LLM, last passes can include LLM and human review of social factors.
Attributes themselves are real (quality proven) and are thusly not garbage in the 'garbage in garbage out' risk - that risk is measured in how much nonsense the dimensional explosion generates that makes it past heuristic filters.