N-Body Gravitational Simulation (Earth–Moon–Sun Model)

A C++ and OpenGL–based N-body simulation using the Velocity Verlet integration method.
This project is part of a collaborative research effort with Prof. John L. Gustafson, a pioneer in High-Performance Computing (HPC) and numerical accuracy.

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About Prof. John L. Gustafson

Prof. John L. Gustafson is an American computer scientist known for groundbreaking contributions in parallel computing, performance modeling, and computer arithmetic.

Key Achievements:

• Invented Gustafson’s Law — a fundamental principle in parallel computing that redefined scalability analysis.
• Introduced the first commercial computer cluster, leading to today’s parallel supercomputers.
• Winner of the inaugural Gordon Bell Award (1988) for exceptional achievement in parallel processing.
• Developed QUIPS (Quality Improvement Per Second) — a metric for measuring real-world computing performance.
• Created the Posit and Unum number systems, alternatives to IEEE floating-point arithmetic, offering superior accuracy and energy efficiency.
• Authored The End of Error: Unum Computing (2015), exploring the next generation of numerical computation.
• Recipient of the IEEE Computer Society Golden Core Award and multiple R&D 100 Awards.
• Holds degrees from Caltech (B.S., Applied Mathematics) and Iowa State University (M.S., Ph.D., Applied Mathematics).

Prof. Gustafson’s ongoing research explores b-posits — a bounded variant of the posit number system — and their potential for improving numerical stability in large-scale scientific computations.

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About This Project

This repository implements a three-body gravitational model (Sun–Earth–Moon) to study numerical precision and dynamic range in floating-point systems — particularly as a testbed for b-posit arithmetic.

Research Goal

The goal is to evaluate how different arithmetic representations (IEEE floats vs. b-posits) handle extreme scale variation in gravitational problems:

[ F = G \frac{m_1 m_2}{r^2} ]

This simulation is especially suitable because:

• The gravitational constant G is extremely small (~6.674×10⁻¹¹),
• Masses (m₁, m₂) are huge (10²⁴–10³⁰ kg),
• Distances (r) are astronomical (10⁶–10¹¹ m).

Such combinations produce numerical edge cases where rounding, overflow, or loss of significance can distort results — making it an excellent benchmark for new number systems like b-posits.

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Technical Overview

Languages & Libraries

• C++17 for simulation logic
• GLFW + GLAD + OpenGL for visualization
• GLM (OpenGL Mathematics) for vector math
• CMake for cross-platform builds

Core Components

Module	Purpose
physics/solver.*	Implements Velocity Verlet integration for motion
physics/body.*	Defines celestial body properties (mass, position, velocity)
render/renderer.*	Handles OpenGL rendering of trajectories
utils/constants.*	Physical constants (G, masses, orbital radii)

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Features

• Real-time simulation of Sun, Earth, and Moon
• Accurate gravitational dynamics using the Velocity Verlet method
• OpenGL rendering with colored trails for each body
• Modular architecture for future extension (e.g., b-posit arithmetic)
• Clean CMake build system — runs on macOS, Linux, and Windows

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Next Steps

• Implement b-posit arithmetic to replace IEEE floating-point operations.
• Run comparative accuracy tests between float, double, and b-posit.
• Visualize orbital drift or instability due to limited precision.
• Extend to N > 3 bodies for generalized dynamic range experiments.

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Build Instructions

Prerequisites

• CMake ≥ 3.10
• GLFW
• GLM
• OpenGL drivers

Build & Run

git clone https://github.com/Asiwaju-Adeniyi/Fogo-Folu.git
cd Physics-Simulation-Project
cmake -S . -B build
cmake --build build
./build/AsiwajuAdeniyi