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Equation 6 · Part 1 · Comparing the Main Approaches to Scientific Instruments and Metrology

Symbol h

h≈5×10−22h \approx 5 \times 10^{-22}
hh

What this part means

h is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.

Its job in the formula

h is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.

The passage around this formula

…in the microscopy sense. Ground-based gravitational-wave interferometers are the sharpest publicly documented example: designed to detect a fractional change in arm length, expressed as strain, as small as roughly h ≈\approx 5 ×\times 10^{-22} — a distortion far smaller than a proton’s diameter integrated over a kilometers-long arm [ 10 ] . Reaching that sensitivity is a story about noise budgeting rather than a single dominant limitation: shot noise from the random arrival of photons in the laser beam limits…

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A variable is a named place for a value. Its letter is a local label: x can mean position in one formula and a data point in another.

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