Aerial of Branching

|↑| Aerial | Aerial of Branching

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The Branching trunk is for standard concepts.

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Academics

Academic Institutes

• Center for Astrophysics (CfA) ○˒

Applications

• ❪𖣐₃ₐ’❫ Citation Managers ○

Center for Astrophysics & People

• ❪◔❫ CfA Scientists ○

CfA Scientists

• James F. (”Jack”) Steiner ○̉

Citation Managers

• Zotero ○˒

Classes

• Academic Journal ○꠹
• Citation ○꠹

Domains

• Bibliography ○𓆪

Sets & Institutes

• ❪◔❫ Academic Institutes ○

Algebra

Classes

• Polynomial ○꠹
• Linear Equation ○꠹

Common

• Substitution ○

Exponential Function

• Exponential Function (eˣ) ○◂

Functions

• Absolute Value (┃x┃) ○◂
• Discriminant ○◂
• Exponential Function (nˣ) ○◂
• Logarithm (logₙ₍x₎) ○◂

Logarithm

• Natural Logarithm (ln₍x₎) ○◂
• Common Logarithm (log₁₀₍x₎) ○◂

Operations

• Factorial (!) ○◂

Polynomial

• Binomial ○꠹
• Quadratic ○꠹

Recipes

• Polynomial Long Division ○◂

Rules

• Associative Property ○◂
• Commutative Property ○◂
• Distributive Property ○◂
• Binomial Theorem ○◂
• Zero-Product Property ○◂
• Quadratic Formula ○◂
• Polynomial Remainder Theorem ○◂

Analysis

Common

• Time Domain ○
• Convolution ○
• Frequency Domain ○

Domains

• Fourier Analysis ○𓆪

Functions

• Delta Function ○◂
• Fourier Transform ○◂
• Gamma Function (Γ₍x₎) ○◂

Arithmetic

Classes

• Carry ○꠹

Functions

• Greatest Common Divisor (GCD) ○◂
• Lowest Common Denominator (LCD) ○◂
• Least Common Multiple (LCM) ○◂

Operations

• Addition (+) ○◂
• Division (÷) ○◂
• Exponentiation (xⁿ) ○◂
• Multiplication (×) ○◂
• Subtraction (-) ○◂
• Root (ⁿ√x) ○◂

Recipes

• Long Division ○◂

Root

• Cube Root (∛x) ○◂
• Square Root (√x) ○◂

Astronomy

Astronomical Coordinate Systems

• International Celestial Reference System (ICRS) ○˒
• World Coordinate System (WCS) ○˒
• ❪◔❫ Standard Epochs ○

Astronomical Coordinates

• Right Ascension ○◂
• ❪𝛿”❫ Astronomical Dates ○
• Declination ○◂

Astronomical Dates

• Julian Day (JD) ○◂

Astronomical Dates: Julian Day

• Heliocentric Julian Day (HJD) ○◂
• Modified Julian Day (MJD) ○◂

Astronomical Objects

• ❪◑❫ Galaxies ○
• ❪◑❫ Nebulae ○
• ❪◑❫ Novae ○
• ❪◑❫ Star Systems ○
• ❪◑❫ Galaxy Clusters ○
• ❪◑❫ Supernova Remnants ○
• ❪◑❫ White Dwarves ○

Classes

• Accretion Disk ○꠹
• Astronomical Object ○꠹
• Color-Color Diagram ○꠹
• Compact Object ○꠹
• Cosmic Ray ○꠹
• Catalog ○꠹
• Jet ○꠹
• Epoch ○꠹
• Lagrange Point ○꠹
• Orbit ○꠹
• Stellar Wind ○꠹
• Survey ○꠹
• Light Curve ○꠹

Classes of Astronomical Objects

• Active Galactic Nucleus (AGN) ○꠹
• Black Hole ○꠹
• Blazar ○꠹
• Cataclysmic Variable Star (CV) ○꠹
• Binary Star ○꠹
• Galaxy Cluster ○꠹
• Galaxy ○꠹
• Gamma-Ray Burst ○꠹
• Nebula ○꠹
• Neutron Star ○꠹
• Nova ○꠹
• Magnetar ○꠹
• Pulsar ○꠹
• Quasar ○꠹
• Star System ○꠹
• Supernova Remnant (SNR) ○꠹
• Supernova ○꠹
• Tidal Disruption Event ○꠹
• Star ○꠹
• White Dwarf ○꠹
• Wolf-Rayet Star ○꠹
• X-Ray Binary (XRB) ○꠹

Common

• Accretion ○͒
• Azimuth ○
• Celestial Sphere ○
• Color Index ○
• Gravitational Collapse ○
• Interstellar Medium ○
• Outer Space ○
• Quiescence ○
• Roche Lobe ○
• Roche Sphere ○
• Observation ID (ObsID) ○
• Telluric Contamination ○

Constellations

• Ophiuchus ○˒

Domains

• Astrometry ○𓆪
• Galactic Astronomy ○𓆪
• Observational Astronomy ○𓆪
• Optical Astronomy ○𓆪
• Extragalactic Astronomy ○𓆪

File Formats

• FITS ○˒

Functions

• Initial Mass Function (IMF) ○◂
• Mass Function ○◂

Galaxies

• Andromeda Galaxy ❍
• Milky Way ❍
• Triangulum Galaxy ❍
• Large Magellanic Cloud ❍

Galaxy Clusters

• Local Group ❍

Instrumentation

• ❪𖣐₂’❫ Observatories ○

Nebulae & Supernova Remnants

• Crab Nebula ❍

Novae

• T Coronae Borealis ❍

Observatories

• AstroSat ○̉
• Gaia ○̉
• Vera C. Rubin Observatory ○̉

Particulars

• International Space Station (ISS) ○̉

Quantities

• Orbital Frequency ○◂
• Orbital Period (P𝘰𝘳𝘣) ○◂
• Spectral Index (α) ○◂
• Eddington Luminosity (L𝘌𝘥𝘥) ○◂
• Velocity Curve Half-Amplitude (K₂) ○◂
• ❪𝛿’❫ Astronomical Coordinates ○

Quantities & Spectral Fitting Parameters

• Absorbing Column Density (nH) ○◂
• Orbital Inclination (i) ○◂
• Redshift (z) ○◂
• Source Mass (M) ○◂
• Source Distance (D) ○◂

Rules

• Kepler’s Laws ○◂

Sets

• ❪◑❫ Constellations ○
• ❪◑❫ Surveys ○
• ❪◔❫ Telemetry Networks ○
• ❪◑❫ Astronomical Coordinate Systems ○
• ❪◕❫ Astronomical Objects ○

Sets & Institutes

• ❪◕❫ Space Agencies ○

Software

• DS9 ○˒

Software & Python Libraries

• Astropy ○˒

Source Mass

• Primary Mass (M₁) ○◂
• Secondary Mass (M₂) ○◂

Space Agencies

• European Space Agency (ESA) ○˒
• JAXA ○˒
• NASA ○˒

Standard Epochs

• J200 ○˒

Star Systems

• Alpha Centauri ❍

Surveys

• Sloan Digital Sky Survey ○˒

Telemetry Networks

• Deep Space Network (DSN) ○˒
• Tracking and Data Relay Satellite System (TDRSS) ○˒

Units & Units of Length

• Astronomical Unit (AU) ○◂
• Parsec (pc) ○◂

Boolean

Classes

• Implicant ○꠹
• K-Map ○꠹
• Don’t-Care Term ○꠹
• Minterm ○꠹
• Maxterm ○꠹
• Truth Table ○꠹

Classes & Classes of Functions

• Boolean Function ○꠹

Implicant

• Prime Implicant ○꠹

Rules

• De Morgan’s Laws ○◂
• Consensus Theorem ○◂

C

C Libraries

• SQLite ○˒

Particulars & C Libraries

• C Standard Library ○˒

Sets

• ❪◔❫ C Libraries ○

Calculus

Classes

• Antiderivative ○꠹
• Integral ○꠹
• Limit ○꠹
• Derivative ○꠹
• Infinitesimal ○꠹
• Series ○꠹

Common

• Gradient ○

Operations

• Integration (ₐ∫ᵇ) ○◂
• Limit-taking (lim) ○◂
• Antidifferentiation (∫) ○◂
• Differentiation (d∕dx) ○◂

Rules

• L’Hôpital’s Rule ○◂

Sequences

• Riemann Sum ○◂

Series

• Taylor Series ○◂
• Power Series ○꠹

Chemistry

Chemical Elements

• Hydrogen (H) ❍
• Iron (Fe) ❍
• Oxygen (O) ❍
• Silicon (Si) ❍

Classes

• Ion ○꠹
• Isotope ○꠹
• Lewis Structure ○꠹

Common

• Elemental Abundance ○
• Ionization ○
• Stoichiometry ○

Hydrogen

• Tritium ❍

Quantities

• Atomic Mass ○◂

Quantities & Physical Dimensions

• Amount of Substance (n) ○◂

Sets

• ❪◕❫ Chemical Elements ○

States of Matter

• Solid ○

States of Matter & Fluids

• Gas ○
• Liquid ○
• Plasma ○

Classical Mechanics

Classes

• Harmonic Oscillator ○꠹

Common

• Inertia ○

Domains

• Dynamics ○𓆪
• Hamiltonian Mechanics ○𓆪
• Kinematics ○𓆪
• Lagrangian Mechanics ○𓆪
• Newtonian Mechanics ○𓆪
• Statics ○𓆪

Rules

• Newton’s Laws of Motion ○◂

Combinatorics

Classes

• Combination ○꠹
• Permutation ○꠹

Rules

• Rule of Product ○◂

Computer

Applications

• Microsoft Office ○˒
• Zoom ○˒
• ❪𖣐₃ₐ’❫ PDF Software ○
• MeshLab ○˒
• ❪𖣐₃ₐ’❫ Presentation Software ○
• ❪𖣐₃ₐ’❫ Spreadsheet Software ○
• ❪𖣐₃ₐ’❫ Text Editors ○
• ❪𖣐₃ₐ’❫ Web Browsers ○
• ❪𖣐₃ₐ’❫ Virtual Machines ○

Binary Arithmetic

• Fixed-Point Arithmetic ○
• Floating-Point Arithmetic ○

Classes

• Array ○꠹
• Bitstream ○꠹
• Command-Line Interface (CLI) ○꠹
• Computer Algebra System (CAS) ○꠹
• Computer Language ○꠹
• Computer ⚪
• Character ○꠹
• Directory ○꠹
• Driver ○꠹
• Emulator ○꠹
• Executable ○꠹
• Field ○꠹ꟲᴼᴹᴾ
• File Format ○꠹
• Environment Variable ○꠹
• File ○꠹
• Fork ○꠹
• Graphical User Interface (GUI) ○꠹
• Modal ○꠹
• Path ○꠹
• Platform ○꠹
• Process ○꠹
• Hardware ⚪
• Program ○꠹
• Signed Number Representations ○꠹
• Software ⚪
• Thread ○꠹
• Turing Machine ○꠹
• Virtual Drive ○꠹
• Symbolic Link ○꠹
• Volume ○꠹ꟲᴼᴹᴾ
• Virtual Machine ○꠹
• Windowing System ○꠹

Classes & Architectural Units

• Processor ○꠹

Classes & Classes

• Computer Network ○꠹

Classes of Files

• Archive File ○꠹
• Configuration File ○꠹

Classes of Files & Archive File

• Package ○꠹

Classes of Software

• Application Software ○꠹
• Operating System ○꠹
• Utility Software ○꠹

Classes of Software & Package

• Package Manager ○꠹

Common

• Binary Arithmetic ○
• Bit Numbering ○
• Character Encoding ○
• Computer Graphics ○
• Configuration ○
• Copy-Paste ○
• Data Recovery ○
• Disk Partitioning ○
• Execution ○
• File Synchronization ○
• Input∕Output ○
• Memory ○
• Mounting ○
• Overflow ○
• Parallel Computing ○
• Sign Extension ○
• Storage ○
• Virtualization ○

Computer Graphics

• 3D Computer Graphics ○
• Raster Graphics ○
• Vector Graphics ○

Disk Storage

• Hard Drive (HDD) ○꠹
• Optical Disk ○꠹

Domains

• Scientific Computing ○𓆪

Domains & Domains

• Computer Algebra ○𓆪

File

• Filename ○꠹

File Formats

• CSV ○˒
• ISO ○˒
• JSON ○˒
• PDF ○˒
• SVG ○˒
• TOML ○˒
• VHD ○˒

File Formats & XML

• Office Open XML ○˒

File Formats: Office Open XML

• XLSX ○˒

File Formats: VHD

• VHDX ○˒

Filename

• Filename Extension ○꠹

Historical Computers

• ENIAC ○̉

Historical Computers: ENIAC

• EDVAC ○̉

Input

• Reading ○

Input Devices

• Keyboard ○꠹

Input∕Output

• Input ○
• Output ○

Linux Distributions

• Debian ○˒

Linux Distributions: Debian

• Ubuntu ○˒

Memory

• Non-Volatile Memory ○
• Volatile Memory ○

Method of Complements

• Ones’ Complement ○
• Two’s Complement ○

Non-Volatile Memory

• Flash Memory ○
• Read-Only Memory (ROM) ○

Operating Systems

• Unix ○˒
• Windows ○˒

Operating Systems & Unix

• ❪𖣐₃”❫ Unix-Likes ○

Operations

• Modulo ○◂
• Pop ○◂
• Push ○◂

Output

• Writing ○

Output Devices

• Display ○꠹

Output Devices: Display

• Monitor ○꠹

Package Managers

• Conda ○˒

Particulars

• ASCII ○˒
• IEEE 754 ○˒
• Internet ○˒
• Unicode ○˒

Peripherals

• ❪◑❫ Output Devices ○
• ❪◑❫ Input Devices ○

Presentation Software & Microsoft Office

• PowerPoint ○˒

Process

• Child Process ○꠹

Processor

• Microprocessor ○꠹

Processor & Architectural Units

• Central Processing Unit (CPU) ○꠹

Random-Access Memory

• Dynamic Random-Access Memory (DRAM) ○
• Static Random-Access Memory (SRAM) ○

Read-Only Memory

• Programmable Read-Only Memory (PROM) ○

Sets

• ❪◑❫ Peripherals ○
• ❪◔❫ Historical Computers ○️

Signed Number Representations

• Method of Complements ○
• Sign–Magnitude ○

Software

• ❪𖣐₃’❫ Operating Systems ○
• ❪𖣐₃’❫ Shells ○

Solid-State Storage

• Solid-State Drive (SSD) ○꠹

Spreadsheet Software & Microsoft Office

• Excel ○˒

Storage

• Disk Storage ○
• Magnetic Storage ○
• Object Storage ○
• Solid-State Storage ○

Text Editors

• Emacs ○˒
• Vim ○˒

Unicode

• UTF-8 ○˒

Units

• FLOPS ○◂

Units of Information

• Bit (b) ○◂

Units of Information & Bit

• Byte (B) ○◂

Units of Information: Byte

• Megabyte (MB) ○◂
• Gigabyte (GB) ○◂
• Kilobyte (KB) ○◂

Unix-Likes

• GNU ○˒
• BSD ○˒
• Solaris ○˒

Unix-Likes & GNU

• Linux ○˒

Unix-Likes & Linux

• ❪𖣐₃'''❫ Linux Distributions ○

Unix-Likes: BSD

• FreeBSD ○˒

Utilities

• ❪𖣐₃ₑ’❫ Package Managers ○

Virtual Machines

• QEMU ○˒
• VirtualBox ○˒

Virtualization

• Hardware Virtualization ○

Volatile Memory

• Random-Access Memory (RAM) ○

Computer Engineering

Architectural Units

• Arithmetic Logic Unit (ALU) ○꠹
• Control Unit ○꠹
• Execution Unit ○꠹
• Instruction Unit ○꠹
• Load-Store Unit ○꠹

Classes

• Assembly Language ○꠹
• Bus ○꠹
• Datapath ○꠹
• Hardware Register ○꠹
• Instruction Set Architecture (ISA) ○꠹
• Instruction ○꠹
• Memory Address ○꠹
• Interrupt ○꠹
• Opcode ○꠹
• Program Counter (PC) ○꠹
• Register File ○꠹
• Stack Machine ○꠹
• Word ○꠹ꟲᴼᴹᴾ

Classes of Registers

• Instruction Register ○꠹
• Memory Address Register (MAR) ○꠹
• Memory Buffer Register (MBR) ○꠹
• Status Register ○꠹

Common

• Computer Architecture ○
• Machine Code ○
• Instruction Cycle ○

Computer Architecture

• Microarchitecture ○

Hardware Register

• Processor Register ○꠹

Instruction Set Architectures

• x86 ○˒

Memory Address

• Addressability ○
• Addressing Mode ○꠹

Memory Address & Classes of Spaces

• Address Space ○꠹

Memory Address & Decoder

• Address Decoder ○꠹

Particulars

• Little Computer 3 ○˒

Sets

• ❪◕❫ Instruction Set Architectures ○
• ❪◔❫ Architectural Units ○

Continuum Mechanics

Domains

• Magnetohydrodynamics (MHD) ○𓆪

Quantities

• Buoyancy ○◂
• Viscosity ○◂
• Stress ○◂

Sets

• ❪◑❫ Fluids ○

Cosmology

Classes

• Distance Measure ○꠹
• Weakly Interacting Massive Particle (WIMP) ○꠹

Common

• Dark Energy ○
• Dark Matter ○

Data

Classes

• Bin ○꠹
• Database ○꠹
• Image ○꠹
• Histogram ○꠹
• Lookup Table ○꠹
• Document ○꠹
• Pixel ○꠹
• Spreadsheet ○꠹
• Newline ○꠹
• Table ○꠹

Classes & Classes of Functions

• Hash Function ○꠹

Common

• Binning ○
• Data Reduction ○
• Data ⚪
• Optical Character Recognition (OCR) ○
• Metadata ○
• Text ○
• Sorting ○

Data

• Digital Data ○

Domains

• Coding Theory ○𓆪

Table

• Column ○꠹
• Row ○꠹

Electrical Engineering

Adder

• Full Adder ○꠹
• Half Adder ○꠹

Circuit Devices

• Comparator ○꠹
• Adder ○꠹
• Decoder ○꠹
• Encoder ○꠹
• Subtractor ○꠹
• Multiplexer (MUX) ○꠹

Classes

• Circuit ⚪
• Clock Signal ○꠹
• Conductor ○꠹
• Counter ○꠹
• Flip-Flop ○꠹
• IC Power-Supply Pin ○꠹
• Integrated Circuit ○꠹
• Junction ○꠹
• Logic Level ○꠹
• Semiconductor ○꠹
• Transistor ○꠹
• Wire ○꠹

Classes of Circuits

• Asynchronous Circuit ○꠹
• Electronic Circuit ○꠹
• Parallel Circuit ○꠹
• Series Circuit ○꠹
• Short Circuit ○꠹

Common

• Alternating Current (AC) ○
• Aperture ○
• Combinational Logic ○
• Circuit Simulation ○
• Direct Current (DC) ○
• Gain ○
• Ground ○
• Sequential Logic ○
• Vignetting ○

Domains

• Electronics ○𓆪
• Logic Design ○𓆪

Electronic Components

• Diode ○꠹
• Switch ○꠹
• Dual In-Line Package (DIP) ○꠹

Electronic Components & Capacitance

• Capacitor ○꠹

Electronic Components & Resistance

• Resistor ○꠹

Electronic Test Equipment

• Ammeter ○꠹
• Multimeter ○꠹
• Oscilloscope ○꠹
• Voltmeter ○꠹
• Wattmeter ○꠹

Field-Effect Transistor

• MOSFET ○

Flip-Flop

• D Flip-Flop ○꠹
• JK Flip-Flop ○꠹

Functions

• Point Spread Function ○◂

Logic Gates & Conjunction

• AND Gate ○꠹

Logic Gates & Disjunction

• OR Gate ○꠹

Logic Gates & Exclusive Disjunction

• XOR Gate ○꠹

Logic Gates & Exclusive Non-Disjunction

• XNOR Gate ○꠹

Logic Gates & Negation

• Inverter (NOT Gate) ○꠹

Logic Gates & Non-Disjunction

• NOR Gate ○꠹

Logic Gates & Sheffer Stroke

• NAND Gate ○꠹

MOSFET

• CMOS ○

Quantities

• Effective Area (Aₑ) ○◂
• Exposure Time ○◂

Resistor

• Pull-Up Resistor ○꠹

Rules

• Kirchhoff’s Voltage Law ○◂
• Ohm’s Law ○◂

Sets

• ❪◑❫ 4000-Series Integrated Circuits ○
• ❪◑❫ Electronic Test Equipment ○
• ❪◔❫ Circuit Devices ○
• ❪◕❫ Electronic Components ○
• ❪◕❫ Logic Gates ○

Transistor

• Field-Effect Transistor (FET) ○꠹

Electromagnetism

Common

• Absorption ○ᴱᴸᴱ
• Electromagnetic Radiation ○
• Light ○
• Photoelectric Effect ○
• Photoionization ○
• Polarization ○

Domains

• Polarimetry ○𓆪

Electrical Quantities

• Capacitance (C) ○◂
• Charge (q) ○◂
• Conductance (G) ○◂
• Electric Potential (V) ○◂
• Electric Flux ○◂
• Inductance (L) ○◂
• Resistance (R) ○◂
• Electric Power (P) ○◂

Electrical Quantities & Electric Potential

• Voltage (∆V) ○◂

Electrical Quantities & Physical Dimensions

• Current (I) ○◂

Electrical Quantities: Electromagnetic Field

• Electric Field ○◂

Electrical Units & Capacitance

• Farad (F) ○◂

Electrical Units & Charge

• Coulomb (C) ○◂

Electrical Units & Current

• Ampere (A) ○◂

Electrical Units & Inductance

• Henry (H) ○◂

Electrical Units & Resistance

• Ohm (Ω) ○◂

Electrical Units & Voltage

• Volt (V) ○◂

Electromagnetism

• Electricity ⚪
• Magnetism ⚪

Magnetic Quantities

• Magnetic Flux ○◂

Magnetic Quantities: Electromagnetic Field

• Magnetic Field ○◂

Quantities

• Electromagnetic Field ○◂

Engineering

Classes

• Surrogate Model ○꠹
• Transfer Function ○꠹

Domains

• Engineering Design ○𓆪

Excel

Particulars

• VBA ○˒

Extra_

Capitalization

• Camel Case ○
• Snake Case ○

Common

• Letter Case ○
• Subscript ○
• Superscript ○

Companies

• IBM ○˒
• Cloudflare ○˒
• Amazon ○˒
• Microsoft ○˒
• Texas Instruments ○˒

Domains

• Anthropology ○𓆪
• Business ○𓆪
• Sociology ○𓆪
• Typography ○𓆪

Institutes

• International Organization for Standardization (ISO) ○˒

People

• Alan Turing ○̉
• Albert Einstein ○̉
• Brook Taylor ○̉
• Carl Friedrich Gauss ○̉
• Gottfried Wilhelm Leibniz ○̉
• George Boole ○̉
• Guillaume de l’Hôpital ○̉
• Euclid ○̉
• Isaac Newton ○̉
• Johannes Kepler ○̉
• Joseph Fourier ○̉
• William Rowan Hamilton ○̉
• Thomas Bayes ○̉
• Joseph-Louis Lagrange ○̉

Sets

• ❪◕❫ People ○
• ❪◕❫ Companies ○
• ❪◕❫ Institutes ○

Geometry

Classes

• Conic Section ○꠹
• Coordinate System ○꠹
• Angle ○꠹
• Curve ○꠹
• Euclidean Vector ○꠹
• Line ○꠹
• Grid ○꠹
• Fractal ○꠹
• Geometric Transformation ○꠹
• Parabola ○꠹
• Plane ○꠹
• Solid Angle ○꠹

Common

• Euclidean Distance ○
• Isotropy ○
• Origin ○
• Position ○
• Graph of a Function ○
• Radius ○
• Parallel ○
• Standard Basis ○

Domains

• Topology ○𓆪
• Euclidean Geometry ○𓆪

Quantities & Quantities

• Displacement (s) ○◂
• Area (A) ○◂
• Volume (V) ○◂

Sets

• ❪◕❫ Shapes ○

Shapes

• Circle ○꠹
• Parralelogram ○꠹
• Polygon ○꠹
• Quadrilateral ○꠹
• Triangle ○꠹
• Torus ○꠹
• Square ○꠹

Structures

• 2D ○◂
• 1D ○◂
• 3D ○◂
• Unit Circle ○◂
• Unit Square ○◂

Units & Angle

• Degree (°) ○◂
• Radian (rad) ○◂

Units & Solid Angle

• Steradian (sr) ○◂

GNU

Particulars

• glibc ○˒

Particulars & File Formats

• gzip ○˒

Particulars & Shells

• Bash ○˒

HEASoft

Particulars

• XSELECT ○˒
• XSTAR ○˒

XSPEC & Python Libraries

• PyXSPEC ○˒

High-Energy Astrophysics

ACIS

• Continuous Clocking Mode ○˒

Channel Error

• Channel Error (σ₍I₎≈√C₍I₎) ○￩

Chi-Squared

• Chi-Squared (χ²=Σ₍C₍I₎-Cₚ₍I₎₎²∕σ₍I₎²) ○￩ᴴᴱᴬ

Classes

• Event ○꠹ᴴᴱᴬ
• Response Matrix ○꠹
• Hardness-Intensity Diagram (HID) ○꠹

Common

• Event Grade ○
• Pileup ○
• Quasi-Periodic Oscillation (QPO) ○

Data

• Events List ○꠹
• ❪𖣐₁’❫ X-Ray Data Products ○

diskbb-norm

• diskbb-norm (₍R𝘪𝘯∕D₁₀₎²cos₍i₎) ○￩

Domains

• Gamma-Ray Astronomy ○𓆪
• X-Ray Astronomy ○𓆪

File Formats

• ARF ○˒
• PHA ○˒
• PI ○˒
• RMF ○˒

Functions

• Instrumental Response (R₍I,E₎) ○◂
• Point Spread Function ○◂ᴴᴱᴬ
• Source Spectrum (f₍E₎) ○◂
• Model Spectrum (f₍E, p1, p2, …₎) ○◂

Gamma-Ray Observatories

• Compton Gamma Ray Observatory ○˒
• FERMI ○̉

Hardness Ratio

• Hardness Ratio (HR=₍C₂-C₁₎∕₍C₂+C₁₎) ○￩

HMXB

• A0620-00 ❍
• GRS 1915+105 ❍
• GX 339-04 ❍
• Cygnus X-3 ❍
• Cygnus X-1 ❍
• LMC X-3 ❍
• M33 X-7 ❍
• Swift J1727.8-1613 ❍

Instrumentation

• ❪𖣐₂’❫ Gamma-Ray Observatories ○
• ❪𖣐₂’❫ X-Ray Detectors ○
• ❪𖣐₂’❫ X-Ray Observatories ○

LMXB

• Swift J1753.5-0127 ❍
• MAXI J1820+070 ❍

Mass Function

• Mass Function (f₍M₎≡P𝘰𝘳𝘣K₂³∕2πG=M₁sin³i∕₍1+q₎²) ○￩

Mass Ratio

• Mass Ratio (q≡M₂∕M₁) ○￩

Methods & Methods

• Spectral Fitting ○𓆪

Observed Counts

• Observed Counts (C₍I₎=∫f₍E₎⋅R₍I,E₎⋅dE) ○￩

Particulars

• Lynx ○˒

Photon Counts

• Observed Counts (C₍I₎) ○◂
• Predicted Counts (Cₚ₍I₎) ○◂

Quantities

• Channel Error (σ₍I₎) ○◂
• Count Rate ○◂
• Disk Fraction ○◂
• Effective Area ○◂ᴴᴱᴬ
• Hardness Ratio ○◂
• Instrument Channel (I) ○◂
• Mass Ratio (q) ○◂
• Viscosity Parameter (α) ○◂
• ❪𝛿’❫ Spectral Fitting Parameters ○
• ❪𝛿’❫ Spectral Fitting Statistics ○️
• Photon Counts (C) ○◂

Sets

• ❪◑❫ X-Ray Binaries ○
• ❪◑❫ X-Ray States ○
• ❪◔❫ Spectral Fitting Models ○

Software

• CIAO ○˒
• ❪𖣐₃’❫ Spectral Fitting Packages ○️
• HEASoft ○˒

Software: IXPE

• ixpeobssim ○˒

Structures

• Good Time Interval (GTI) ○◂

Units

• Crab ○◂

X-Ray Binaries

• Hercules X-1 ❍
• ❪◑❫ HMXB ○
• ❪◑❫ LMXB ○

X-Ray Data Products

• Image ○꠹ᴴᴱᴬ
• Light Curve ○꠹ᴴᴱᴬ
• Spectrum ○꠹ᴴᴱᴬ
• Source List ○꠹

X-Ray Detectors: Chandra

• ACIS ○̉
• HRC ○̉

X-Ray Detectors: NuSTAR

• FPMA ○̉
• FPMB ○̉

X-Ray Detectors: Swift

• XRT ○̉
• BAT ○̉

X-Ray Detectors: XMM-Newton

• EPIC ○̉

X-Ray Observatories

• Ariel 5 ○̉
• BeppoSAX ○̉
• Chandra ○̉
• EXOSAT ○̉
• IXPE ○̉
• MAXI ○̉
• NICER ○̉
• Granat ○̉
• NuSTAR ○̉
• RXTE ○̉
• Swift ○̉
• XRISM ○̉
• XMM-Newton ○̉

XRT

• Photon Counting Mode ○˒
• Windowed Timing Mode ○˒

Information

Classes

• Archive ○꠹
• Language ○꠹

Common

• Copying ○
• Information Retrieval ○
• Information ⚪
• Publishing ○
• Readability ○️

Domains

• Information Theory ○𓆪

Language

• Natural Language ○꠹

Instrumentation

Classes

• Gas Counter ○꠹
• Charge-Coupled Device (CCD) ○꠹
• Proportional Counter ○꠹

Common

• Photon Counting ○

Internet

Domain Name System

• Resource Record (RR) ○˒

HTTP

• HTTPS ○˒

MIME

• MIME Type ○꠹

Particulars

• Domain Name System (DNS) ○˒
• File Transfer Protocol (FTP) ○˒
• HTTP ○˒
• Internet Protocol Suite ○˒
• MIME ○˒
• Secure Sockets Layer (SSL) ○˒

Particulars & Secure Sockets Layer

• Transport Layer Security (TLS) ○˒

Resource Record

• CNAME Record ○˒

JavaScript

Common

• JavaScript Syntax ○

JavaScript Libraries

• Luxon ○˒
• Moment.js ○˒

Particulars

• Bun ○˒
• CommonJS ○˒
• esbuild ○˒
• Node.js ○˒

Particulars & Package Managers

• npm ○˒

Sets & Libraries

• ❪◔❫ JavaScript Libraries ○

Linear Algebra

Classes

• Linear Transformation ○꠹
• System of Linear Equations ○꠹

Classes & Classes of Spaces

• Null Space ○꠹

Common

• Eigenvalue ○
• Eigenvector ○
• Linear Combination ○
• Linear Span ○
• Minor ○
• Rank ○
• Row Echelon Form ○
• Linear Independence ○
• Trace ○

Common & Classes of Spaces

• Row Space ○
• Column Space ○

Functions

• Determinant ○◂

Hamming Codes

• Hamming(7,4) ○◂

Linear Codes

• ❪∂₂”❫ Hamming Codes ○

Matrix Operations

• Matrix Exponential ○◂
• Transpose ○◂

Recipes

• Gaussian Elimination ○◂
• ❪∂₂’❫ Linear Codes ○

Vector Operations

• Dot Product ○◂

Linux

Particulars

• Network Block Device (NBD) ○˒

Particulars & File Systems

• ext4 ○˒

Particulars & Package Managers

• APT ○˒

Logic

Classes

• Boolean ○꠹
• Literal ○꠹

Common

• Absorption ○ᴸᴼᴳᴵꟲ
• Completeness ○ᴸᴼᴳᴵꟲ
• Simplification ○ᴸᴼᴳᴵꟲ

Logical Connectives

• Conjunction (AND) ○◂
• Disjunction (OR) ○◂
• Negation (NOT) ○◂
• Non-Disjunction (NOR) ○◂
• Sheffer Stroke (NAND) ○◂

Logical Connectives: Disjunction

• Exclusive Disjunction (XOR) ○◂

Logical Connectives: Non-Disjunction

• Exclusive Non-Disjunction (XNOR) ○◂

Operations

• ❪∂₁ₐ’❫ Logical Connectives ○

Quantities

• False ❍
• True ❍

Machine Learning

Chatbots

• ChatGPT ○˒
• Claude ○˒

Classes

• Autoencoder ○꠹
• Large Language Model ○꠹

Classes & Classes

• Neural Network ○꠹

Classes & Classes of Functions

• Loss Function ○꠹

Common

• Artificial Intelligence ○
• Dimensionality Reduction ○
• Hyperparameter Optimization ○
• Principal Component Analysis ○
• Transformer ○ᴹᴸ

Neural Network

• Recurrent Neural Network ○꠹

Sets

• ❪◑❫ Chatbots ○

Markdown

Applications

• Obsidian ○͒

Particulars

• Quartz ○˒

Mathematics

Classes

• Algorithm ○꠹
• Argument of a Function ○꠹
• Canonical Form ○꠹
• Coefficient ○꠹
• Constant ○꠹
• Equation ○꠹
• Expression ○꠹
• Formula ○꠹
• Function ○꠹
• Graph ○꠹
• Identity Element ○꠹
• Identity ○꠹
• Inequality ○꠹
• Law ○꠹
• Mathematical Object ○꠹
• Model ○꠹
• Moment ○꠹
• Multiplicative Inverse ○꠹
• Numeral System ○꠹
• Operator ○꠹
• Parameter ○꠹
• Parametric Equation ○꠹
• Quantity ○꠹
• Statement ○꠹
• Sum ○꠹
• System of Equations ○꠹
• Theorem ○꠹
• Value ○꠹
• Variable ○꠹

Classes & Classes

• Cycle ○꠹

Classes of Functions

• Binary Function ○꠹
• Identity Function ○꠹
• Inverse Function ○꠹
• Mapping ○꠹
• Involution ○꠹
• Monotonic Function ○꠹
• Operation ○꠹
• Periodic Function ○꠹
• Transformation ○꠹
• Unary Function ○꠹

Classes of Matrices

• Augmented Matrix ○꠹
• Coefficient Matrix ○꠹
• Elementary Matrix ○꠹
• Identity Matrix ○꠹
• Inverse Matrix ○꠹
• Rotation Matrix ○꠹
• Square Matrix ○꠹
• Transformation Matrix ○꠹
• Zero Matrix ○꠹
• Triangular Matrix ○꠹

Classes of Numbers

• Complex Number ○꠹
• Fraction ○꠹
• Integer ○꠹
• Imaginary Number ○꠹
• Negative Number ○꠹
• Positive Number ○꠹
• Real Number ○꠹

Classes of Operations

• Binary Operation ○꠹
• Unary Operation ○꠹

Classes of Spaces

• Parameter Space ○꠹
• Vector Space ○꠹

Common

• Approximation ○
• Calculation ○
• Codomain ○
• Computation ○
• Domain ○
• Equality ○
• Image ○
• Order of Operations ○
• Positional Notation ○
• Radix ○
• Range of a Function ○
• Rounding ○
• Sign ○
• Simplification ○
• Truncation ○

Common & Common

• Density ○
• Dimension ○
• Flux ○
• Oscillation ○
• Distance ○

Constants

• Euler’s Number (e) ❍
• Imaginary Unit (i) ❍
• Pi (π) ❍

Domains

• Arithmetic ○𓆪
• Combinatorics ○𓆪
• Graph Theory ○𓆪
• Numerical Analysis ○𓆪
• Optimization ○𓆪

Functions

• Ceiling Function ○◂
• Floor Function ○◂

Infinities

• Infinity (∞) ○◂

Integers

• -1 ❍
• 0 ❍
• 1 ❍
• 10 ❍
• 16 ❍
• 2 ❍
• 8 ❍

Numbers

• ❪𝛿₁’❫ Integers ○

Numeral Systems

• Binary ○₂
• Decimal ○₁₀
• Hexadecimal ○₁₆
• Octal ○₈

Quantities

• Amplitude ○◂

Sequence Operations

• Sequence Multiplication (∏) ○◂
• Summation (Σ) ○◂

Sequences & Operations

• ❪∂₄’❫ Sequence Operations ○

Sets

• ❪◕❫ Numeral Systems ○

Types

• Matrix ○꠹
• Number ○꠹
• Scalar ○꠹
• Sequence ○꠹
• Set ○꠹
• Space ○꠹
• Tensor ○꠹
• Tuple ○꠹
• Vector ○꠹

MATLAB

Common

• MATLAB Syntax ○

Mechanics

Common

• Mass Distribution ○
• Motion ⚪
• Rotation ○

Force

• Force (F=m⋅a) ○￩

Quantities

• Acceleration (a) ○◂
• Force (F) ○◂
• Pressure (p) ○◂
• Radial Velocity ○◂
• Momentum (p) ○◂
• Velocity (v) ○◂
• Speed (v) ○◂
• Weight (W) ○◂
• Work (W) ○◂

Rotational Quantities

• Angular Frequency (ω) ○◂
• Angular Momentum (L) ○◂
• Torque (τ) ○◂
• Rotational Frequency (ν) ○◂

Work

• Work (W=F⋅s) ○￩

Methodology

Classes

• Best Practice ○꠹

Common

• Heuristics ○
• Simulation ○

Domains

• Design ○𓆪

Metrology

Calibration

• Cross-Calibration ○

Classes

• Unit ○꠹

Common

• Accuracy ○
• Calibration ○
• Measurement ⚪
• Precision ○
• Significand ○
• Significant Figures ○
• Unit Conversion ○

Domains

• Instrumentation ○𓆪
• Telemetry ○𓆪

ISO Standards

• ISO 8601 ○˒

Sets

• ❪◑❫ ISO Standards ○
• ❪◑❫ Metric Prefixes ○
• ❪◑❫ Systems of Measurement ○

Systems of Measurement

• CGS Units ○˒
• International System of Units (SI) ○˒
• MKS Units ○˒

Networks

Classes

• Communication Protocol ○꠹
• Network ⚪

Domains

• Network Theory ○𓆪

Obsidian

Dataview

• DataviewJS ○˒

Obsidian Plugins

• Dataview ○˒
• Dataview Serializer ○˒
• Templater ○˒

Sets

• ❪◔❫ Obsidian Plugins ○

Operating System

Classes

• File System ○꠹
• Kernel ○꠹
• System Call ○꠹
• Shell ○꠹

Common

• Clipboard ○
• Focus ○
• Scheduling ○

File System

• Hierarchical File System ○꠹
• Journaling File System ○꠹

Sets

• ❪◑❫ File Systems ○

Physics

Classes

• Fluid ○꠹
• Particle ○꠹
• Physical Field ○꠹
• Physical Object ○꠹
• Physical Quantity ○꠹
• Redshift ○꠹
• Wave ○꠹

Classes & Classes

• Atom ○꠹

Common

• Advection ○
• Frame of Reference ○
• Matter ⚪
• Radiation ○
• Time ⚪

Common & Classes of Spaces

• Space ⚪

Constants

• Gravitational Constant (G) ❍
• Speed of Light (c) ❍

Forces

• Electromagnetism ⚪
• Gravity ⚪

Frame of Reference

• Inertial Frame of Reference ○

Quantities

• Area Density (ρ𝐴) ○◂
• Density (ρ) ○◂
• Energy (E) ○◂
• Frequency (f) ○◂
• Period ○◂
• Phase (φ) ○◂
• Power (P) ○◂
• ❪𝛿’❫ Physical Dimensions ○

Quantities & Physical Dimensions

• Length (l) ○◂
• Mass (m) ○◂

Sets

• ❪◕❫ Forces ○

Sets & Sets

• ❪◕❫ States of Matter ○

Units & Frequency

• Hertz (Hz) ○◂

Units & Power

• Watt (W) ○◂

Units of Energy

• Electronvolt (eV) ○◂
• Erg ○◂
• Joule (J) ○◂

Units of Length

• Meter (m) ○◂

Units of Mass

• Dalton ○◂

Wave

• Soliton ○꠹

Probability

Classes

• Cumulative Distribution Function (CDF) ○꠹
• Probability Density Function (PDF) ○꠹
• Probability Distribution ○꠹
• Probability Mass Function (PMF) ○꠹
• Moment Generating Function (MGF) ○꠹
• Quantile ○꠹
• Random Variable ○꠹

Common

• Probability ⚪

Domains

• Bayesian Probability ○𓆪
• Frequentist Probability ○𓆪

Exponential Distribution

• Exponential Distribution (Exp₍λ₎=λ⋅exp₍-λx₎) ○￩
• Exponential Distribution (Exp₍β₎=₍1∕β₎⋅exp₍-x∕β₎) ○￩

Functions

• Likelihood (L) ○◂
• Prior (p₍θ₎) ○◂
• ❪∂₁’❫ Probability Distributions ○
• Posterior (p₍θ┃X₎) ○◂

Methods

• Bayesian Inference ○𓆪
• Frequentist Inference ○𓆪

Probability

• Conditional Probability ○

Probability Distributions

• Bernoulli Distribution (Bernoulli₍p₎) ○◂
• Beta Distribution (Beta₍α,β₎) ○◂
• Binomial Distribution (B₍n,p₎) ○◂
• Gamma Distribution (Gamma₍α,β₎) ○◂
• Geometric Distribution (Geom₍p₎) ○◂
• Inverse Gamma Distribution (InvGamma₍α,β₎) ○◂
• Normal Distribution (N₍μ,σ²₎) ○◂
• Hypergeometric Distribution (Hypergeom₍N,K,n₎) ○◂
• Negative Binomial Distribution (NB₍r,p₎) ○◂
• Poisson Distribution (Pois₍λ₎) ○◂
• Uniform Distribution (U₍a,b₎) ○◂

Probability Distributions: Gamma Distribution

• Chi-Squared Distribution (χ²₍k₎) ○◂
• Exponential Distribution (Exp₍λ₎) ○◂

Rules

• Bayes’ Theorem ○◂

Programming

Applications

• ❪𖣐₃ₐ’❫ Integrated Development Environments ○

Assignment

• Parallel Assignment ○

Class

• Inner Class ○꠹

Classes

• Application Programming Interface (API) ○꠹
• Attribute ○꠹
• Block ○꠹
• Branch ○꠹
• Breakpoint ○꠹
• Call Stack ○꠹
• Class ○꠹ᴾᴿᴳᴿᴹ
• Command ○꠹
• Comment ○꠹
• Conditional ○꠹
• Constant ○꠹ᴾᴿᴳᴿᴹ
• Delimiter ○꠹
• Docstring ○꠹
• Escape ○꠹
• Expression ○꠹ᴾᴿᴳᴿᴹ
• Generator ○꠹
• Identifier ○꠹
• Instance ○꠹
• Integrated Development Environment (IDE) ○꠹
• Label ○꠹
• List Comprehension ○꠹
• Literal ○꠹ᴾᴿᴳᴿᴹ
• Loop ○꠹
• Macro ○꠹
• Mask ○꠹
• Metasyntactic Variable ○꠹
• Method ○꠹ᴾᴿᴳᴿᴹ
• Name-Value Pair ○꠹
• Object ○꠹ᴾᴿᴳᴿᴹ
• Operator ○꠹ᴾᴿᴳᴿᴹ
• Parameter ○꠹ᴾᴿᴳᴿᴹ
• Pointer ○꠹
• Property ○꠹ᴾᴿᴳᴿᴹ
• Read-Eval-Print Loop (REPL) ○꠹
• Reference ○꠹
• Regular Expression (Regex) ○꠹
• Stack Trace ○꠹
• Statement ○꠹ᴾᴿᴳᴿᴹ
• Translator ○꠹
• Value ○꠹ᴾᴿᴳᴿᴹ
• Variable ○꠹ᴾᴿᴳᴿᴹ
• Wildcard ○꠹

Classes & Classes

• Data Type ○꠹

Classes & Classes of Algorithms

• Sorting Algorithm ○꠹
• In-Place Algorithm ○꠹

Classes & Classes of Functions

• Function ○꠹ᴾᴿᴳᴿᴹ

Classes & Classes of Spaces

• Namespace ○꠹

Classes & Computer Language

• Markup Language ○꠹
• Programming Language ○꠹

Classes & Translator

• Interpreter ○꠹
• Compiler ○꠹

Classes of Programmatic Functions

• Anonymous Function ○꠹
• Constructor ○꠹
• Operation ○꠹ᴾᴿᴳᴿᴹ
• Wrapper Function ○꠹

Classes of Programmatic Functions: Wrapper Function

• Helper Function ○꠹

Classes of Programmatic Objects

• Callable Object ○꠹
• File Object ○꠹
• Function Object ○꠹

Classes of Programmatic Operations

• Bitwise Operation ○꠹
• String Operation ○️꠹

Common

• Aliasing ○
• Array Slicing ○
• Assignment ○
• Code Completion ○
• Code Style ○
• Command History ○
• Comparison ○
• Concatenation ○
• Control Flow ○
• Coupling ○
• Debugging ○
• Documentation ○
• Evaluation ○
• Exception Handling ○
• Find and Replace ○
• Foobar ○
• Garbage Collection ○
• Garbage ○
• Globbing ○
• Identity ○ᴾᴿᴳᴿᴹ
• Iteration ○
• Just-In-Time Compilation ○
• Lint ○
• Logging ○
• Name Binding ○
• Name Collision ○
• Object Copying ○
• Pretty Printing ○
• Recursion ○
• Refactoring ○
• Scope ○
• Semantics ○
• Serialization ○
• Syntax ○
• Testing ○
• Typing ○
• Vectorization ○

Computer Languages

• ❪◑❫ Markup Languages ○
• ❪◑❫ Programming Languages ○

Data Types

• Array ○꠹ᴾᴿᴳᴿᴹ
• Boolean ○꠹ᴾᴿᴳᴿᴹ
• Collection ○꠹
• Date ○꠹ᴾᴿᴳᴿᴹ
• List ○꠹
• Scalar ○꠹ᴾᴿᴳᴿᴹ
• Container ○꠹
• Set ○꠹ᴾᴿᴳᴿᴹ
• Stack ○꠹
• String ○꠹
• Tuple ○꠹ᴾᴿᴳᴿᴹ

Data Types & Classes of Numbers

• Number ○꠹ᴾᴿᴳᴿᴹ

Data Types: Array

• Associative Array ○꠹

Data Types: Number

• Integer ○꠹ᴾᴿᴳᴿᴹ
• Floating-Point Number (Float) ○꠹

Domains

• Object-Oriented Programming ○𓆪
• Modular Programming ○𓆪

Evaluation

• Lazy Evaluation ○

Functions

• Map ○◂ᴾᴿᴳᴿᴹ

Global Scope

• Global Variable ○꠹

Integrated Development Environments

• VS Code ○͒

Literal

• String Literal ○꠹

Local Scope

• Local Variable ○꠹

Loop

• For Loop ○꠹
• While Loop ○꠹

Markup Languages

• HTML ○˒
• Markdown ○˒
• YAML ○˒
• ❪◑❫ Style Sheet Languages ○
• LaTeX ○˒

Markup Languages & File Formats

• XML ○˒

Object Copying

• Deep Copy ○
• Shallow Copy ○

Particulars

• Amazon S3 ○˒
• Backus–Naur Form ○˒
• Document Object Model (DOM) ○˒
• Git ○˒
• Tesseract ○˒

Programming Language

• High-Level Programming Language ○꠹
• Low-Level Programming Language ○꠹
• Scripting Language ○꠹

Programming Languages

• Ada ○˒
• C ○˒
• IDL ○˒
• Java ○˒
• JavaScript ○˒
• Fortran ○˒
• Julia ○˒
• Lisp ○˒
• Lua ○˒
• Perl ○˒
• Python ○͒
• R ○˒
• MATLAB ○˒
• Rust ○˒
• S ○˒
• Tcl ○˒
• ❪◑❫ Query Languages ○

Programming Languages: C

• C++ ○˒
• C＃ ○˒

Programming Languages: JavaScript

• TypeScript ○˒

Query Languages

• SQL ○˒

Scope

• Global Scope ○
• Local Scope ○

Semantics

• Static Semantics ○

Sets

• ❪◑❫ Libraries ○
• ❪◔❫ Linters ○
• ❪◕❫ Computer Languages ○

String

• Empty String ○

Style Sheet Languages

• CSS ○˒

VS Code Extensions

• Rainbow CSV ○˒

VS Code Extensions & Linters

• Ruff ○˒

Python

Common

• Python Syntax and Semantics ○

Particulars

• Anaconda ○˒
• CPython ○˒
• IPython ○˒
• PyPy ○˒

Particulars & Package Managers

• pip ○˒

Particulars & Python Libraries

• Python Standard Library ○˒

Python Libraries

• Beautiful Soup ○˒
• Matplotlib ○˒
• Boto3 ○˒
• dateutil ○˒
• NumPy ○˒
• NLTK ○˒
• PyTorch ○˒
• pandas ○˒
• PyMuPDF ○˒
• SciPy ○˒
• Requests ○˒

Sets & Libraries

• ❪◔❫ Python Libraries ○

Quantum Mechanics

Classes

• Axion ○꠹

Common

• Bremsstrahlung ○
• Compton Scattering ○
• Observer Effect ○
• Pair Production ○

Compton Scattering

• Inverse Compton Scattering ○

Elementary Particles & Bosons

• Photon ❍

Elementary Particles & Fermions & Subatomic Particles

• Electron ❍

Quantities

• Photon Energy (E) ○◂

Quantities & Spectral Fitting Parameters

• Electron Temperature ○◂

Sets

• ❪◑❫ Subatomic Particles ○

Sets & Subatomic Particles

• ❪◕❫ Elementary Particles ○

Subatomic Particles

• Neutron ❍
• Proton ❍
• ❪◑❫ Bosons ○
• ❪◑❫ Fermions ○

R

Common

• R Syntax ○

Radiometry

Domains

• Photometry ○𓆪

Photometric Quantities

• Luminous Intensity (Iᵥ) ○◂
• Luminous Flux (Φᵥ) ○◂

Quantities

• Albedo ○◂
• Intensity ○◂
• Radiance ○◂
• Radiant Energy (Qₑ) ○◂
• Radiant Flux (Φₑ) ○◂
• Luminosity (L) ○◂

Relativity

Common

• Event Horizon ○
• Innermost Stable Circular Orbit (ISCO) ○
• Spacetime ○
• Synchrotron Radiation ○

Dimensionless Spin

• Dimensionless Spin (a∗=a∕R𝘨) ○￩

Domains

• General Relativity ○𓆪
• Special Relativity ○𓆪

Gravitational Radius

• Gravitational Radius (R𝘨≡GM∕c²) ○￩

ISCO Radius

• ISCO Radius (R𝘪𝘴𝘤𝘰=6R𝘨) ○￩

Quantities

• Gravitational Radius (R𝘨) ○◂
• ISCO Radius (R𝘪𝘴𝘤𝘰) ○◂
• Lorentz Factor ○◂
• Schwarzschild Radius (R𝘴) ○◂
• Spin (a) ○◂
• Black Hole Angular Momentum (J) ○◂

Schwarzschild Radius

• Schwarzschild Radius (R𝘴=2R𝘨) ○￩

Spin

• Spin (a=J∕cM) ○￩

Spin & Spectral Fitting Parameters

• Dimensionless Spin (a∗) ○◂

Structures

• Schwarzschild Metric ○◂
• Kerr Metric ○◂

Scientific Computing

Calculator

• Graphing Calculator ○꠹
• Scientific Calculator ○꠹

Calculators

• ❪◑❫ Graphing Calculators ○
• ❪◑❫ Scientific Calculators ○

Classes

• Computational Notebook ○꠹
• Calculator ○꠹
• Plot ○꠹

Graphing Calculators

• TI-Nspire ○̉

Particulars

• Jupyter ○˒
• PGPLOT ○˒

Sets

• ❪◕❫ Calculators ○

Set Theory

Classes

• Index Set ○꠹
• Indexed Family ○꠹
• Interval ○꠹
• Partition ○꠹

Common

• Enumeration ○
• Complement ○
• Counting ○

Operations

• Union ○◂

Signal Processing

Classes

• Analog Signal ○꠹
• Digital Signal ○꠹

Common

• Noise ○
• Sampling ○
• Signal ⚪
• Signal-to-Noise ○

Functions

• Power Density Spectrum ○◂
• Spectral Density ○◂

Sets

• ❪◕❫ Waveforms ○

Waveforms

• Sawtooth Wave ○꠹
• Sine Wave ○꠹
• Square Wave ○꠹

Software Engineering

Classes

• DevTools ○꠹
• Repository ○꠹
• Design Pattern ○꠹

Common

• Unit Testing ○
• Version Control ○

Spectral Fitting

Spectral Fitting Normalization Parameters: diskbb

• diskbb-norm ○◂

Spectral Fitting Normalization Parameters: gauss

• gauss-norm (K) ○◂

Spectral Fitting Normalization Parameters: Nthcomp

• nthcomp-norm ○◂

Spectral Fitting Normalization Parameters: powerlaw

• powerlaw-norm (K) ○◂

Spectral Fitting Normalization Parameters: simpl

• Scattered Fraction (f𝘴𝘤) ○◂

Spectral Fitting Packages

• ISIS ○˒
• SPEX ○˒

Spectral Fitting Packages & CIAO

• Sherpa ○˒

Spectral Fitting Packages & HEASoft Particulars

• XSPEC ○͒

Spectral Fitting Parameters

• Inner-Disk Temperature (T𝘪𝘯) ○◂
• Inner-Disk Radius (R𝘪𝘯) ○◂
• Line Energy (E𝘭) ○◂
• Line Width (σ) ○◂
• Mass Accretion Rate (M˙) ○◂
• Spectral Hardening Factor (f𝘤𝘰𝘭) ○◂
• Photon Index (Γ) ○◂
• ❪𝛿”❫ Spectral Fitting Normalization Parameters ○

Spectral Fitting Statistics

• Cash Statistic ○◂
• Chi-Squared (χ²) ○◂ᴴᴱᴬ

Spectroscopy

Classes

• Gamma Ray ○꠹
• Spectral Line ○꠹
• Spectrum ○꠹
• X-Ray ○꠹

Classes & Classes of Spaces

• Color Space ○꠹

Color

• Spectral Color ○

Colors

• Black ○
• White ○

Common

• Color ○
• Hardness ○

Sets

• ❪◕❫ Colors ○

X-Ray

• Hard X-Ray ○꠹
• Soft X-Ray ○꠹

Statistics

Chi-Squared

• Reduced Chi-Squared (χᵥ²) ○◂

Classes

• Error ○꠹ˢᵗᵃᵗˢ
• Hypothesis Test ○꠹
• Mean ○꠹
• Percentage ○꠹
• Markov Chain ○꠹
• Power Law ○꠹
• Monte Carlo Method ○꠹
• Residual ○꠹
• Statistic ○꠹

Common

• Correlation ○
• Estimation ○
• Fisher Information ○
• Covariance ○
• Goodness of Fit ○
• Normalization ○
• Uncertainty ○
• Weighting ○
• Null Hypothesis ○
• Significance ○

Covariance & Classes of Matrices

• Covariance Matrix ○꠹

Hypothesis Test

• Chi-Squared Test ○꠹

Markov Chain & Monte Carlo Method & Classes of Algorithms

• Markov Chain Monte Carlo (MCMC) ○꠹

Mean

• Weighted Mean ○꠹

Normalization

• Normalizing Constant ○꠹
• Quantile Normalization ○

Quantities

• Degrees of Freedom ○◂
• Variance (σ²) ○◂
• ❪𝛿’❫ Statistics ○
• Root Mean Square ○◂
• Standard Deviation (σ) ○◂

Statistic

• Test Statistic ○꠹

Statistics

• Chi-Squared (χ²) ○◂

Systems

Classes

• Finite-State Machine ○꠹
• State Diagram ○꠹
• State Table ○꠹
• System ⚪

Common

• Feedback ○
• Scalability ○
• State ○

Thermodynamics

Blackbody

• Blackbody Radiation ○

Classes

• Blackbody ○꠹

Common

• Thermal Radiation ○

Quantities & Physical Dimensions

• Temperature (T) ○◂

Time

Classes

• Calendar ○꠹
• Clock ○꠹
• Date ○꠹
• Timer ○꠹
• Day ○꠹

Quantities & Physical Dimensions

• Time (t) ○◂

Trigonometry

Classes

• Trigonometric Function ○꠹

Functions

• Cosine (cos₍x₎) ○◂
• Sine (sin₍x₎) ○◂

Unix

Classes

• Device File ○꠹

Common

• Unix Filesystem ○

Particulars

• Filesystem Hierarchy Standard (FHS) ○˒
• POSIX ○˒
• S-Lang ○˒
• X Window System ○˒

Particulars & File Formats

• tar ○˒

Particulars & Shells

• Bourne Shell (sh) ○˒

VS Code

Sets

• ❪◔❫ VS Code Extensions ○

Windows

Particulars

• Mark of the Web ○˒
• File Explorer ○˒
• Task Scheduler ○˒
• Microsoft C ○˒
• Windows NT ○˒
• Alternate Data Stream (ADS) ○˒
• Windows Registry ○˒
• WSL ○˒

Particulars & File Systems

• NTFS ○˒
• FAT ○˒

Particulars & Package Managers

• winget ○˒

Particulars & Shells

• Command Prompt ○˒
• PowerShell ○˒

WSL

Particulars

• wslu ○˒

Zotero

Sets

• ❪◔❫ Zotero Plugins ○

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