Genesis

Matter, computed before your eyes.
A free physics simulator for Windows, Linux and macOS: build atoms and molecules, fuse two nuclei, go all the way down to quarks.

Download for Windows · Download for Linux · Download for macOS · Website · Lire en français

Nothing in Genesis is scripted. A Python physics engine moves time forward and applies the laws of physics; every event happens at the moment the law decides, and comes with the calculation behind it. The numbers come from reference data: NIST, NUBASE2020, AME2020, PDG, CODATA, REACLIB.

Four areas to explore

The atom

Pick any of the 118 elements, then add or remove protons, neutrons and electrons. The atom responds: an excited electron falls back and emits a photon, an unstable nucleus decays at the moment drawn from its half-life.

• The electron cloud in 3D, shell by shell
• A tunable laser: the photon is absorbed, passes through, or knocks an electron out
• The decay chain from uranium to lead, with time you can speed up
• The nucleus seen as a vibrating drop

Nuclear fusion

Choose any two nuclei and the collision energy. The engine computes the approach, the electric repulsion, quantum tunnelling, then what is left: a fusion, a bounce or a fission.

• The collision at its true scale, then up close at contact
• The fields and forces at work at every instant
• A detailed report: products, energy released, probabilities

The molecular laboratory

Place atoms on the bench or start from a ready-made molecule. The semi-empirical GFN1-xTB model computes the electronic state, energy and forces as the structure relaxes or moves.

• Molecular structures, including water, benzene and gold clusters
• Polarization halos, deformation density and molecular orbitals in 3D
• Localized electron pairs and two-centre or multicentre bonds
• Temperature, dynamics, normal modes and isotope selection
• Detailed energy terms and comparisons with reference measurements
• A 2D assembler: draw a molecule, have it checked by the calculation, then simulate it in 3D
• A reactor piston: the pressure measured on the wall, or imposed from 100 to 20,000 atm

The subatomic world

Fire an electron at a nucleon and watch what happens, assemble your own hadrons from quarks, and look inside the proton at different resolutions.

• Collisions told step by step
• A workshop to build hadrons and check whether they hold together
• The Standard Model table, every line computed or measured
• The sea of partons that appears as you look closer

Download — version 0.5.0

File	Use
Genesis-0.5.0.exe	Windows installer: adds Genesis to the Start menu and the desktop
Genesis-0.5.0-portable.zip	Windows portable: extract the whole archive, then run Genesis/Genesis.exe
Genesis-0.5.0-linux-x64.deb	Debian/Ubuntu x86-64 installer: adds Genesis to the applications menu
Genesis-0.5.0-linux-x64.tar.gz	Linux portable: extract, then run Genesis/bin/Genesis
Genesis-0.5.0-macos-arm64.dmg	macOS Apple Silicon disk image: open, then drag Genesis to Applications
Genesis-0.5.0-macos-arm64.zip	macOS Apple Silicon portable: extract, then open Genesis.app

Java and the Python engine are bundled: no separate Java or Python installation is required. All calculations run on your computer, with no account. Genesis sends usage statistics (no name, no e-mail) to guide its development; they can be turned off in ⚙, see the privacy notice. English is the default; French is available from the language menu. All versions are on the Releases page.

First launch. The engine loads its data, which can take several dozen seconds. A loading screen stays up until it is ready.

Windows warning. This version is not digitally signed yet. If Windows SmartScreen shows a warning, click More info, then Run anyway. You can check that your download is intact against the SHA-256 checksums in CHECKSUMS-SHA256.txt:

Get-FileHash .\Genesis-0.5.0.exe -Algorithm SHA256

Linux. On Debian/Ubuntu, install the downloaded package with sudo apt install ./Genesis-0.5.0-linux-x64.deb. For the portable archive, run tar -xzf Genesis-0.5.0-linux-x64.tar.gz and then ./Genesis/bin/Genesis. A desktop with GTK 3 is required. The Linux engine log is at ${XDG_STATE_HOME:-~/.local/state}/genesis/logs/engine.log.

macOS. Apple Silicon (arm64) only. Open the .dmg and drag Genesis to Applications, or extract the .zip and open Genesis.app. The package is not notarized: if macOS blocks the first launch, right-click the app, choose Open, then confirm. You can also clear the quarantine flag with xattr -dr com.apple.quarantine /Applications/Genesis.app. The engine log is at ~/Library/Logs/Genesis/engine.log.

If the engine does not start, its log is at %LOCALAPPDATA%\Genesis\logs\engine.log on Windows, ${XDG_STATE_HOME:-~/.local/state}/genesis/logs/engine.log on Linux, or ~/Library/Logs/Genesis/engine.log on macOS. Send it through the contact page, along with your operating system version.

Support the project

Genesis is designed and built independently. If you enjoy it:

• ⭐ Star this repository. It is the simplest way to help, and it shows me people are using it.
• 👀 Watch → Custom → Releases to be notified of new versions.
• Tell people about it, and send ideas or bugs through the contact page.

License

Genesis is free to install and use, for personal or professional purposes, on as many computers as you own. It is proprietary software: you may not sell, redistribute or modify it. See the full end-user license agreement. This repository contains the official downloads; the source repository is maintained separately.

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© 2026 Gemmie · genesis.gemmi-e.com · Portfolio & contact · GitHub