As Above So Below Contents 1 Precession 1 1.1 Torque-free .............................................. 1 1.2 Torque-induced ............................................ 2 1.2.1 Classical (Newtonian) ..................................... 2 1.2.2 Relativistic .......................................... 4 1.3 Astronomy ............................................... 4 1.3.1 Axial precession (precession of the equinoxes) ........................ 4 1.3.2 Perihelion precession ..................................... 5 1.4 See also ................................................ 5 1.5 References ............................................... 5 1.6 External links ............................................. 5 2 Zodiac 6 2.1 Usage ................................................. 6 2.2 History ................................................ 6 2.2.1 Early history ......................................... 6 2.2.2 Hellenistic and Roman era .................................. 7 2.2.3 Hindu zodiac ......................................... 8 2.2.4 Middle Ages ......................................... 8 2.2.5 Early modern ......................................... 8 2.3 The twelve signs ............................................ 9 2.4 Constellations ............................................. 9 2.5 Table of dates ............................................. 10 2.6 Precession of the equinoxes ...................................... 10 2.7 In modern astronomy ......................................... 11 2.8 Mnemonics .............................................. 11 2.9 Unicode characters .......................................... 11 2.10 See also ................................................ 12 2.11 References .............................................. 12 2.12 External links ............................................. 13 3 Language 14 3.1 Definitions ............................................... 15 i ii CONTENTS 3.1.1 Mental faculty, organ or instinct ............................... 16 3.1.2 Formal symbolic system ................................... 16 3.1.3 Tool for communication ................................... 16 3.1.4 Unique status of human language ............................... 17 3.2 Origin ................................................. 17 3.3 The study of language ......................................... 18 3.3.1 Subdisciplines ......................................... 18 3.3.2 Early history ......................................... 19 3.3.3 Contemporary linguistics ................................... 19 3.4 Physiological and neural architecture of language and speech ..................... 20 3.4.1 The brain and language .................................... 20 3.4.2 Anatomy of speech ...................................... 20 3.5 Structure ................................................ 22 3.5.1 Semantics ........................................... 22 3.5.2 Sounds and symbols ...................................... 22 3.5.3 Grammar ........................................... 24 3.5.4 Typology and universals .................................... 26 3.6 Social contexts of use and transmission ................................ 26 3.6.1 Usage and meaning ...................................... 27 3.6.2 Language acquisition ..................................... 27 3.6.3 Language and culture ..................................... 28 3.6.4 Writing, literacy and technology ............................... 28 3.6.5 Language change ....................................... 29 3.6.6 Language contact ....................................... 30 3.7 Linguistic diversity .......................................... 30 3.7.1 Languages and dialects .................................... 31 3.7.2 Language families of the world ................................ 31 3.7.3 Language endangerment ................................... 32 3.8 See also ................................................ 32 3.9 Notes ................................................. 32 3.9.1 Commentary notes ...................................... 33 3.9.2 Citations ........................................... 33 3.10 Works Cited .............................................. 35 3.11 External links ............................................. 38 4 Language family 39 4.1 Structure of a family .......................................... 39 4.1.1 Dialect continua ........................................ 40 4.1.2 Isolates ............................................ 40 4.1.3 Proto-languages ........................................ 40 4.2 Other classifications of languages ................................... 40 4.2.1 Sprachbund .......................................... 40 CONTENTS iii 4.2.2 Contact languages ....................................... 41 4.3 See also ................................................ 41 4.4 Notes ................................................. 41 4.5 Further reading ............................................ 41 4.6 External links ............................................. 42 5 Writing 43 5.1 Means for recording information ................................... 43 5.1.1 Writing systems ........................................ 43 5.1.2 Tools and materials ...................................... 45 5.2 History ................................................. 45 5.2.1 Neolithic writing ....................................... 45 5.2.2 Mesopotamia ......................................... 45 5.2.3 Elamite scripts ........................................ 46 5.2.4 China ............................................. 46 5.2.5 Egypt ............................................. 46 5.2.6 Indus Valley .......................................... 47 5.2.7 Turkmenistan ......................................... 47 5.2.8 Phoenician writing system and descendants .......................... 47 5.2.9 Mesoamerica ......................................... 47 5.2.10 South America ........................................ 48 5.2.11 Dacia (Romania) ....................................... 48 5.3 Creation of textual or written information ............................... 48 5.3.1 Composition ......................................... 48 5.3.2 Creativity ........................................... 48 5.3.3 Author ............................................ 48 5.3.4 Writer ............................................. 48 5.3.5 Critiques ........................................... 48 5.4 See also ................................................ 48 5.5 Notes ................................................. 48 5.6 References ............................................... 49 5.7 Further reading ............................................ 49 5.8 External links ............................................. 50 6 Chaldea 51 6.1 Land .................................................. 51 6.2 Chaldean people ............................................ 52 6.3 History ................................................. 53 6.3.1 End of the Chaldean dynasty ................................. 56 6.4 See also ................................................ 57 6.5 References ............................................... 57 6.6 External links ............................................. 58 iv CONTENTS 7 Scythia 59 7.1 Geography ............................................... 59 7.2 First Scythian kingdom ........................................ 59 7.3 Second Scythian kingdom ....................................... 60 7.3.1 Scythia at the end of the 5th to 3rd centuries BC ....................... 60 7.4 Later Scythian kingdoms ....................................... 61 7.5 Scythian kings ............................................. 62 7.6 Scythian tribes ............................................. 62 7.7 See also ................................................ 62 7.8 Art and literature ........................................... 62 7.9 References ............................................... 63 7.10 External links ............................................. 63 7.11 Text and image sources, contributors, and licenses .......................... 64 7.11.1 Text .............................................. 64 7.11.2 Images ............................................ 68 7.11.3 Content license ........................................ 71 Chapter 1 Precession For other uses, see Precession (disambiguation). culated with respect to separate coordinate axes (e.g. x, Precession is a change in the orientation of the rota- y, z), or basis sets. If an object is asymmetric around its principal axis of rotation, the moment of inertia with respect to each basis will change with time, while preserv- ing angular momentum. The result is that the component angular velocities around each axis will vary inversely to each axis’ moment of inertia. Poinsot’s ellipsoid is a ge- ometrical analog of the functions that govern torque-free motion of a rotating rigid body. The torque-free precession rate of an object with an axis of symmetry, such as a disk, spinning about an axis not aligned with that axis of symmetry can be calculated as follows: Is!s [1] !p = Ip cos(α) where !p is the precession rate, !s is the spin rate about the axis of symmetry, Is is the moment of inertia about the axis of symmetry, Ip is moment of inertia about either of the other two equal perpendicular principal axes, and α is the angle between the moment of inertia direction [2] Precession of a gyroscope and the symmetry axis. When an object is not perfectly solid, internal vortices will tional axis of a rotating body. In an appropriate