RESEARCH BASE
Search 3,721 documents across 34 fields — every claim tier-rated by evidence
3,633 are the core, quality-scored corpus (34 lettered sections — see How We Work); the remaining 88 are cross-corpus synthesis documents (68 InterDocs, 12 Connections, 8 Theories) also indexed here.
198 results for "sound pressure level" — page 10 of 10
O_3_06 — Tidal Phenomena, Maelstroms & Coastal Anomalies
Earth's tides — generated primarily by the gravitational interactions between the Earth, Moon, and Sun — produce a range of extreme and visually spectacular phenomena where local bathymetry, coastal geometry, and resonan
D_1_05 — Stonehenge and the British Megalithic Complex
Stonehenge on Salisbury Plain, Wiltshire, is Britain's most iconic prehistoric monument, constructed in multiple phases between approximately 3100 and 1500 BCE — a span of over 1,600 years. The site features massive sars
D_1_09 — Newgrange, Knowth, and Passage Tomb Astronomy
Newgrange, constructed around 3200 BCE in the Boyne Valley (Brú na Bóinne) of County Meath, Ireland, is one of the most remarkable Neolithic structures in the world — older than the Egyptian pyramids by approximately 700
D_1_00 — Iconic Megasites: Subfolder Summary
D_0_00 — Sites & Artifacts: Section Summary
L_2_02 — Population Genetics and Hardy-Weinberg Equilibrium
Population genetics — the mathematical study of allele frequency change in populations — provides the quantitative framework underlying evolutionary biology. The Hardy-Weinberg principle (1908), independently derived by
Y_3_14 — Chanting and Repetitive Vocalization: Sonic Pathways to Trance
Chanting and repetitive vocalization — the sustained production of rhythmic, patterned vocal sounds — is arguably the most ancient and universal method of inducing altered states of consciousness through acoustic means.
R_3_11 — Microevolution and Rapid Adaptation
Microevolution — changes in allele frequencies within populations over generations — is the fundamental engine of biological adaptation. Once assumed to operate too slowly to observe directly, research over the past 50 y
R_1_00 — Origin Early Life: Subfolder Summary
R_1_05 — Quantum Biology
Until recently, quantum effects were thought impossible in warm, wet biological systems. The standard assumption held that thermal noise at physiological temperatures (~310 K) would destroy quantum coherence within femto
ZA_4_03 — The Electromagnetic Spectrum: From Radio Waves to Gamma Rays
The electromagnetic spectrum encompasses all forms of electromagnetic radiation — from radio waves with wavelengths of kilometers to gamma rays with wavelengths smaller than atomic nuclei. Unified by James Clerk Maxwell'
ZA_4_00 — Condensed Matter Thermodynamics: Subfolder Summary
ZA_4_04 — Plasma Physics: The Fourth State of Matter
Plasma — ionized gas in which electrons are stripped from atoms — constitutes over 99% of the visible matter in the universe. Stars, nebulae, the interstellar medium, lightning, and the solar wind are all plasmas. Unlike
V_1_00 — History Cultural: Subfolder Summary
V_1_06 — Mathematics of Music: Harmonic Ratios & Tuning Systems
The relationship between mathematics and music is among the oldest in intellectual history. Pythagoras (c. 570–495 BCE) is traditionally credited with discovering that consonant musical intervals correspond to simple num
V_3_09 — Fourier Analysis: Signal Processing and the Mathematics of Frequency
Fourier analysis — the decomposition of functions into constituent sinusoidal waves — is one of the most transformative mathematical ideas in science and engineering. Joseph Fourier's 1822 insight that any periodic funct
V_3_00 — Applied Mathematics: Subfolder Summary
V_0_00 — Mathematics & Information: Section Summary
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