# Yard: Measuring, Testing, and Verifying Physics

## Purpose

The yard namespace contains practical knowledge about how physics is measured, tested, and verified. From detector design to error analysis, from calibration techniques to the philosophy of experimental confirmation.

## Why This Namespace Exists

Theory is meaningless without measurement. This namespace bridges the gap between equations and the physical world by documenting how we actually verify what theory predicts.

## Topics

### Measurement Techniques
- Interferometry and precision measurement
- Particle detectors: tracking, calorimetry, Cherenkov
- Atomic clocks and timekeeping
- Spectroscopy: absorption, emission, Raman
- Gravitational wave detection: LIGO, Virgo, KAGRA

### Error Analysis
- Statistical errors vs systematic errors
- Monte Carlo simulation for error estimation
- Bayesian vs frequentist approaches
- Uncertainty propagation
- The art of knowing when you're done

### Calibration and Standards
- SI units and their definitions
- Fundamental constants: how we measure them
- Calibration chains: from primary standards to applications
- Cross-calibration between experiments
- The problem of circularity in measurement

### Experimental Philosophy
- What counts as a "definitive" experiment?
- Reproducibility crisis in physics
- The role of null results
- Publication bias and the file drawer problem
- Open data and open source in physics

### Tools of the Trade
- Data acquisition systems
- Real-time analysis pipelines
- Signal processing basics (FFT, filtering, correlation)
- Visualization techniques for experimental data
- Machine learning in experimental physics

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**Note**: This namespace is newly created. Contributions welcome.