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.
53 results for "frequency modulated" — page 2 of 3
Q_4_11 — Acoustics: Sound Physics, Resonance, and Wave Phenomena
Acoustics is the science of sound — mechanical pressure waves propagating through matter (gases, liquids, solids). Unlike electromagnetic waves, sound requires a medium and cannot travel through vacuum. Sound is characte
ZB_1_15 — Infrasound Communication in Wildlife
Infrasound (frequencies below 20 Hz) and low-frequency communication (<100 Hz) are used by elephants, whales, okapi, cassowaries, alligators, and other species for long-range signaling across distances exceeding 10 km. K
ZB_1_18 — Infrasound Communication in Animals: Elephants, Whales & Seismic Signaling
Infrasound — acoustic frequencies below the typical lower limit of human hearing (~20 Hz) — serves as a long-range communication channel for some of Earth's largest animals, enabling coordination over distances of kilome
G_4_06 — Sound Healing — Evidence, Pseudoscience, and Ancient Practice
Sound healing occupies a uniquely contested space where genuine medical science, ancient spiritual practice, and modern pseudoscience coexist and often blur together. On one end, music therapy is FDA-recognized for pain
G_1_16 — Ground-Penetrating Radar in Archaeological Prospection
Ground-Penetrating Radar (GPR) is a non-invasive geophysical survey technique that transmits short pulses of electromagnetic (radar) energy into the ground and records the reflections returned from subsurface interfaces
G_1_19 — Acoustic Archaeology: Sound Mapping of Ancient Structures
Acoustic archaeology (archaeoacoustics) is an emerging interdisciplinary field that investigates the sonic properties of ancient structures, landscapes, and artifacts to understand how past peoples experienced and manipu
G_3_15 — Piezoelectric Effects: Crystals, Geology, and Ancient Technology
Piezoelectricity (from Greek piezein, "to squeeze") is the physical phenomenon whereby certain crystalline materials generate an electric charge when subjected to mechanical stress, and conversely, deform mechanically wh
G_3_07 — Cymatics — Visible Sound and the Physics of Vibration
Cymatics — from the Greek κῦμα (kyma, "wave") — is the study of visible sound patterns formed when a vibrating surface (plate, membrane, or fluid) organizes matter (sand, powder, liquid) into geometric configurations at
G_3_26 — Resonance as Universal Information Encoding
Resonance — the selective amplification of energy at characteristic frequencies — appears across physical, biological, and cognitive systems as a substrate-independent information-encoding mechanism. From radio receivers
G_2_14 — Information Theory Applied to Ancient Scripts and Codes
Information theory — founded by Claude Shannon (1948) — provides a mathematical framework for quantifying the information content, redundancy, and statistical structure of communication systems. When applied to ancient s
O_1_20 — Schumann Resonance
The Schumann resonances are a set of spectral peaks in the extremely low frequency (ELF) portion of the Earth's electromagnetic field spectrum, generated by lightning discharges exciting the resonant cavity formed betwee
O_2_14 — Slow Earthquakes and Episodic Tremor: Silent Seismic Events
Slow earthquakes — a class of seismic events in which fault slip occurs over days to months rather than the seconds to minutes characteristic of conventional earthquakes — represent one of the most significant discoverie
O_4_09 — Singing Sands, Booming Dunes, and Anomalous Desert Acoustics
Singing sands and booming dunes are natural acoustic phenomena in which sand produces audible sound — sometimes at extraordinary volume (up to 105 dB, comparable to a chainsaw at 1 m) — when disturbed by wind, avalanchin
T_5_16 — Psychoacoustics, Binaural Beats, and Sound-Mind Interaction
Psychoacoustics — the scientific study of how humans perceive sound — reveals that hearing is not a passive recording of air pressure changes but an active, constructive neural process shaped by attention, expectation, e
ZD_4_09 — Signal Processing and Fourier Analysis
Signal processing — the analysis, modification, and synthesis of signals (time-varying or spatially varying quantities) — is fundamental to telecommunications, audio engineering, image processing, radar, medical imaging,
L_4_09 — Selective Sweeps and Positive Selection in Humans
A selective sweep occurs when a beneficial allele rises rapidly in frequency under positive natural selection, carrying nearby linked variants along with it (genetic hitchhiking) and reducing genetic variation across the
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
L_5_02 — Genetic Diseases and Founder Effect Populations
When a small group founds a new population and subsequently expands in relative isolation, genetic drift can amplify alleles that were rare in the ancestral population — including deleterious recessive disease alleles. T
Y_5_02 — CIA Gateway Process, Monroe Institute & Hemi-Sync
The CIA's Gateway Process Analysis Report (1983) is a declassified U.S. Army Intelligence document that evaluated the Monroe Institute's Hemi-Sync technology for potential military/intelligence applications. Written by L
Y_5_22 — Brainwave Entrainment: Neural Oscillation, Binaural Beats, and Auditory Driving
Brainwave entrainment refers to the capacity of external rhythmic stimuli — auditory, visual, or electromagnetic — to synchronize endogenous neural oscillation patterns toward the frequency of the stimulus, a phenomenon
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