particle
Enable an agent to recognise a physical particle, record the scale and assumptions under which it is treated as a discrete entity, assess its state, and select valid observations or interventions.
Research draft, second pass
A second pass drafted this model: the structure a model of this thing needs, and what is known about it in the world. The line under this one says how the second half was obtained - researched against sources, or recalled without web access, in which case nothing here was read anywhere and every claim is a lead to verify. Unreviewed either way.
recalled by Codex without web access - no source was read
Researched by: Codex
Purpose and description
Enable an agent to recognise a physical particle, record the scale and assumptions under which it is treated as a discrete entity, assess its state, and select valid observations or interventions.
A particle is a discrete physical entity treated as an individual constituent of a system, whose internal structure and spatial extent may be resolved or neglected according to the scale and purpose of the description.
It can be Classify a candidate particle from measurements while retaining alternative identifications.; Select a classical, quantum, or effective particle description for a stated task.; Estimate transport or interaction outcomes within the chosen description's limits.; Choose an applicable detection, separation, trapping, or scattering method.; Track decay, fragmentation, dissolution, or aggregation and update identity relations.; Identify when a particle description must give way to an internal-structure or collective-system model..
Distinguishing features
The referent is physical; a grammatical particle is related by its name rather than by physical subtype.
The description identifies an entity at a stated scale rather than only an amount of bulk material.
A particle description specifies which internal structure and spatial extent matter, rather than assuming that every particle is pointlike.
An individual particle is distinguished from a population statistic, detector signal, or computational sample representing many particles.
The description states whether classical trajectories or quantum states are appropriate, rather than treating localisation and individual tracking as universally available.
Scope
+ Particle kind and criteria for identifying an individual particle
+ Elementary, composite, grain, and droplet descriptions at an explicit scale
+ Intrinsic properties and context-dependent physical states
+ Interactions, transport, transformation, and persistence
+ Detection evidence, measurement limitations, and particle approximation validity
- Grammatical particles, which belong to a language model and are not physical subtypes
- Bulk materials, continuous media, and particle populations as collective systems
- Fields and waves considered independently of a particle description
- Detectors, accelerators, filters, and other apparatus as devices
- Organisms and manufactured objects as functional wholes, even when approximated as particles
Characteristics
- Particle description
- elementary particle | composite particle | material grain | droplet | unresolved Determines which properties, boundaries, and interaction descriptions apply.
- Composition or species
- Particle species or material composition; unknown permitted Supports identification and constrains possible interactions and transformations.
- Description scale
- Relevant length in m and time in s; probe energy in J or eV where applicable Makes the particle boundary and neglected internal structure explicit.
- Physical regime
- classical | quantum | mixed description; relativistic treatment required or not required Controls which state variables and predictions are meaningful.
- Mass
- kg or eV/c², with invariant or other mass convention stated Informs dynamics and identification without assuming every particle has a rest frame.
- Electric charge
- C or multiples of elementary charge e Constrains electromagnetic response and possible manipulation.
- Size and shape
- m for defined size measures; shape descriptor; unresolved or not applicable permitted Separates geometric extent from effective interaction size and localisation uncertainty.
- Spin quantum number
- Dimensionless spin quantum number where applicable; unspecified otherwise Supports quantum species identification and the appropriate statistical description.
- Motion or quantum state
- Frame-referenced position and momentum, or an applicable quantum-state description, with uncertainty Supports predictions without presuming an exact classical trajectory.
- Surrounding medium and fields
- Links to medium, applied fields, boundaries, and nearby interacting entities Explains environmental effects on transport, charge, stability, and detectability.
- Persistence
- Stable over stated observation interval | decaying | dissolving | fragmenting | aggregating | unresolved Determines whether continued tracking of the same particle remains meaningful.
Where this came from
wikidata · CC0 1.0
Drafted structure
Bundle to layer to finding to question, as the second pass will find it: 6 bundles · 11 layers · 15 findings · 25 questions.
Particle identity and scale Establishes what counts as a particle and what an individual denotes in the current description.
Particle spans several physical regimes, so neither a universal size threshold nor a universal individual-tracking rule is adequate.
Physical referent
Separates a physical particle from similarly named concepts and representational substitutes.
Particle kind and individual
Record whether the referent is a species, a particular physical entity, or a modelling representative.
- Does particle here mean an elementary species, a composite entity, a grain, or a droplet? definition
- Does the record describe one physical particle, a particle kind, or a computational representative of many particles? boundary
Resolution and individuation
Defines the scale and evidence under which a particle can be distinguished and followed.
Individuality at a stated scale
Make explicit the observation resolution, neglected structure, and limits of assigning persistent individual identity.
- At what spatial, temporal, or probe-energy scale is this entity treated as one particle? measurement
- What supports identifying it as the same particle across observations, and where does that assignment cease to be meaningful? boundary
Constitution and physical properties Captures composition, spatial extent, and properties relevant to identifying and interacting with the particle.
Elementary species and material grains require different accounts of structure, size, and property variability.
Composition and extent
Describes internal constituents and applicable measures of physical size.
Resolved structure
Distinguish measured internal structure and geometric extent from an assumed point-particle approximation.
- What constituents or material phases are established, and by which observations? provenance
- Does the reported size mean geometric diameter, hydrodynamic diameter, charge radius, or another defined measure? measurement
Species properties and variable properties
Separates identifying properties from quantities that vary with preparation or environment.
Mass, charge, and spin
Record applicable properties with conventions and distinguish species-level attributes from the current particle state.
- Which mass, charge, and spin quantities are applicable, and what measured or reference evidence supports them? provenance
- Which properties identify the species, and which can change through charging, excitation, or material exchange? boundary
State and motion Represents the particle's physical state using variables appropriate to its regime.
A trajectory suitable for a grain cannot be assumed to describe every quantum particle.
State representation
Chooses a classical or quantum description and states its preparation and uncertainty.
Admissible state description
Record only state quantities meaningful under the selected description, including relevant internal states.
- Does the task require a classical phase-space description, a quantum state, or a reduced statistical description? definition
- Which translational and internal state quantities were prepared or measured, with what uncertainties? measurement
Reference frame and transport
Connects motion to a frame, medium, and valid dynamical approximation.
Motion prediction limits
Specify the frame and conditions under which trajectory, transport, or propagation predictions are valid.
- In which reference frame and surrounding medium are position, momentum, and energy specified? measurement
- Do collisions, drag, diffusion, quantum effects, or relativistic effects determine which motion prediction is usable? action
Interactions and identity change Records responses to other entities and events that alter or terminate particle identity.
Scattering, decay, charging, dissolution, and aggregation have different implications for whether the original particle persists.
Interaction response
Characterises coupling to fields, other particles, media, and surfaces.
Applicable interaction model
Select interaction quantities and interventions appropriate to the particle kind and environment.
- Which interactions matter at the stated energy and scale, and what evidence supports their response parameters? provenance
- Under what conditions could the particle be deflected, trapped, scattered, filtered, or deposited? action
Persistence and products
Distinguishes changes of state from events producing different particles or eliminating a discrete boundary.
Particle continuity
Record the applicable identity criterion and links to products of decay, fragmentation, coalescence, or other transformations.
- Which events preserve this particle's identity, and which end it or create successor particles? boundary
- What lifetime, survival interval, or transformation rate is supported under the stated conditions? measurement
Detection and description validity Connects particle assertions to observation and defines when the chosen description fails.
A signal may be indirect or ambiguous, and a useful particle approximation can fail when structure or collective effects become relevant.
Observation and identification
Relates detector outputs to inferred particle presence, count, and identity.
Signal-to-particle inference
Separate measured signals from inferred properties and retain competing interpretations.
- Which observations support particle presence and species assignment rather than background or another particle type? provenance
- How do detection thresholds, efficiency, resolution, and overlapping signals limit identification or counting? measurement
Approximation breakdown
Defines limits of point-particle, isolated-particle, and persistent-particle descriptions.
Description replacement criteria
Identify task-specific evidence that requires resolving internal structure or moving to a field or collective description.
- Which observable effects would invalidate neglecting the particle's extent, internal structure, or correlations with its surroundings? boundary
- What more detailed or collective model should an agent use when those effects exceed the task's tolerance? action
Evidence and external alignment What the world already says about this thing, gathered so the model can be checked against it.
A model that cannot be lined up against existing standards, identifiers and practice cannot be adopted by anyone who already uses them.
Reported evidence
Findings from the breadth pass, kept separate from the structural claims.
Check these first
Recalled without web access and unsourced; every item is a lead to verify.
- The domain suggests the physical sense, but the registry should establish whether the intended scope is general, subatomic or particulate.
- The listed kinds span different descriptive scales and are not a mutually exclusive classification.
- No universal typical measurement range, identifier scheme or regulatory standard applies across this scope; hazards and uses depend on the particle type.
- Which of these check these first hold for the sense of particle this model covers, and on what evidence? provenance
Kinds and varieties
Recalled without web access and unsourced; every item is a lead to verify.
- Elementary particles
- Composite subatomic particles
- Atoms
- Molecules
- Colloidal particles
- Granular particles
- Which of these kinds and varieties hold for the sense of particle this model covers, and on what evidence? provenance
Real-world use
Recalled without web access and unsourced; every item is a lead to verify.
- Representing bodies as point masses in mechanics
- Describing matter and interactions in particle physics
- Modelling gases and molecular transport
- Characterising aerosols, suspensions and powders
- Using particle beams for imaging, material analysis and treatment
- Which of these real-world use hold for the sense of particle this model covers, and on what evidence? provenance
Failure modes and hazards
Recalled without web access and unsourced; every item is a lead to verify.
- A point-particle approximation can fail when size, shape or internal structure affects the behaviour being studied.
- Airborne particulate matter can present inhalation hazards depending on composition, size and exposure.
- Dispersed combustible powders can present fire and explosion hazards.
- Energetic particle radiation can damage biological tissue and materials.
- Which of these failure modes and hazards hold for the sense of particle this model covers, and on what evidence? provenance
Neighbouring kinds and how to tell them apart
Recalled without web access and unsourced; every item is a lead to verify.
- grammatical particle - A grammatical particle is a linguistic item; this entry covers physical entities.
- elementary particle - An elementary particle has no known constituent substructure; the broader term also includes composite entities.
- point particle - A point particle is an idealisation with no spatial extent; a physical particle need not satisfy that idealisation.
- atom - An atom is a specific kind of entity with a nucleus and bound electrons; particle is a broader descriptive category.
- particulate matter - Particulate matter denotes material consisting of particles, often dispersed in a medium, rather than one individual particle.
- Which of these neighbouring kinds and how to tell them apart hold for the sense of particle this model covers, and on what evidence? provenance
What the second pass must settle
- Does the registry intend particle to cover both elementary particles and material grains or droplets, or a narrower physical sense?
- Should quasiparticles and other effective excitations be included here or linked through a neighbouring model?
- Which existing Vercy world models already own particle concepts or particular subtypes and should supply the authoritative model?
- Which authoritative sources should establish subtype-specific property conventions and criteria for the validity of particle approximations?
- Which identity and observation requirements are needed for the intended tasks, especially where persistent individual labels are unavailable?