Unit-explicit scientific calculator
Search a formula, enter the plasma state, and inspect the calculation, units, scope, and source in one place.
Type to search formula names, canonical symbols, parameters, and common aliases.
Try a broader search term or choose another category.
JSON record includes canonical inputs and outputs, formula provenance, display units, and active applicability warnings.
Canonical meanings are resolved from the shared semantic-symbol registry for this calculator.
| Symbol | Name and physical definition | Role here | Unit and convention |
|---|
Reproducible visualisation
The plots are evaluated directly from the same physics core used by the calculators. They show the implemented equations exactly at the sampled points; physical applicability remains limited by the assumptions of each model.
Choose a preset or enter the fixed state used by both plotting tools.
Ordering diagram
Logarithmic markers compare standard frequencies and spatial scales for the reference state. Their ordering may change with the selected plasma environment.
Controlled parameter sweep
Vary one input while all other state variables remain fixed. Up to three quantities from the same physical family share a common axis and unit.
These plots contain no smoothing, fitting, or interpolated physics. Curves connect direct evaluations of the implemented equations only for readability. A visually smooth trend does not establish model validity, identify a wave mode, or replace uncertainty analysis. Exported files record the displayed values and fixed state.
Worked examples
These examples use illustrative parameter sets to show how the core quantities fit together. They are not reconstructions of specific published events.
Open a state in the calculator, then review every input against the interval, instrument cadence, coordinate system, and species definition used in your analysis.
Semantic evidence taxonomy
Every in-browser record has one explicit semantic class. Source-anchored comparators, identities, unit checks, scientific properties, domain guardrails, regressions, and provenance controls are distinguished rather than treated as equivalent evidence.
v1.1.0; browser source-commit field remains unavailable rather than fabricated
Physics-core provenance v1.0.0 baseline 9ad37ae; v1.1.0 core includes the approved SD-10 correction
The semantic class states what each check can support. A_REFERENCE and C_UNIT require independently anchored expected results; E_DOMAIN exercises a defensible implemented applicability boundary; F_REGRESSION covers internal restatements, fixed regression targets, nominal examples, and smoke checks; P_PROVENANCE identifies artifacts but is not correctness evidence. Passing the present checks does not establish model applicability beyond the specifically exercised boundaries or turn reduced formulas, empirical fits, or simplified instability criteria into general kinetic solvers.
Canonical semantic notation
Project-wide notation, units, species meanings, and convention notes are generated from the same canonical registry used by every calculator.
Display boundary
All selectors convert presentation around the same canonical calculator values. They do not select a different physics implementation.
Complete registry
Search rendered symbols, plain forms, canonical names, semantic IDs, and concise aliases.
| Symbol | Name and physical definition | Canonical/display units | Species and convention |
|---|
About the project
Alfvenica is an independent, open-source browser toolkit that brings commonly used space- and astrophysical-plasma calculations together with their units, assumptions, interpretation, and sources. It is intended for researchers, educators, and learners who want to inspect the model behind a number rather than use a black-box result.
I began developing Alfvenica while working with spacecraft observations and kinetic-Alfvén-wave problems. Repeatedly checking units, conventions, assumptions, and limiting cases was often as important as obtaining the numerical result. The toolkit grew from that practical need.
Alfvenica combines a searchable calculator, physical interpretation, controlled plotting, illustrative plasma states, explicit model assumptions, primary references, and an in-browser validation report. It supports first-pass estimates, teaching, consistency checks, and transparent methods—not automated wave identification.
Calculations and plots run locally through one registered calculation core with explicit unit conventions; input values are not transmitted. Space, SI display, and CGS-oriented mixed choices are interface conversions only; the mixed mode is not a complete Gaussian/esu/emu implementation and retains electrical resistivity and conductivity in SI. Formula definitions, assumptions, references, interpretations, plots, and tests remain separated to reduce scientific drift.
Constants cite CODATA 2022, standard coefficient targets cite the 2023 NRL Plasma Formulary, and model-specific entries retain literature references and stated conditions. The current in-browser evidence includes six source-anchored A_REFERENCE coefficient comparators and one C_UNIT conversion anchor; identities and regression or implementation checks remain separately classified. Development-only scaling checks and the P_PROVENANCE core hash are reported separately in Validation and the formula audit.
Single-ion, scalar-temperature, fluid, reduced two-fluid, bi-Maxwellian, and frozen-flow assumptions appear in several tools. Characteristic scales are usually ordering scales, not sharp universal boundaries. Alfvenica does not replace kinetic dispersion solvers, instrument pipelines, event context, or uncertainty analysis.
ChatGPT and Anthropic Claude assisted with software development, documentation, testing, and technical consistency checks. All AI-assisted outputs incorporated into Alfvenica were reviewed and verified by the author against the source code, scientific references, and numerical tests, as applicable.
Alfvenica is under continuing development. Scientific corrections, independent benchmarks, documentation improvements, code contributions, feedback, and genuine research collaboration are welcome. Report a scientific issue or read the contribution guide.
Chettri, M. K. (2026). Alfvenica: Interactive Space Plasma Toolkit (Version 1.1.0) [Computer software]. Zenodo. https://doi.org/10.5281/zenodo.22061119