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Research draft

annihilation

vr.tr.annihilation · ACT.PRC

Let an agent explain particle annihilation and its physics, relay applications in medical imaging and colliders, distinguish the physics sense from general destruction and from the Sufi concept of fana, and route to entries for related processes.

Thing Registry Activities and processes

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.

written by Claude from model knowledge without web access - no source was read, every claim is a lead to verify

Researched by: Claude

Purpose and description

Let an agent explain particle annihilation and its physics, relay applications in medical imaging and colliders, distinguish the physics sense from general destruction and from the Sufi concept of fana, and route to entries for related processes.

In particle physics, the process in which a particle and its antiparticle collide and convert into other particles or radiation, as in electron-positron annihilation producing photons, which is used in positron emission tomography and in particle colliders; annihilation conserves energy, momentum and quantum numbers, and the word also names total destruction in general usage and, in Sufi thought, the concept of fana, the passing away of the self, which is a separate sense.

What it is for: Not applicable; a physical process with applications in imaging and research.

It can be explain the physics; relay applications; distinguish senses; route to related processes.

Distinguishing features

Matter-antimatter conversion

Conservation laws

Medical imaging use

Homonym with other senses

What it looks like

Not a visible object; detected as photons or particle showers in detectors.

Physical character

electron-positron annihilation photons: 2 photons of 511 keV - at rest

How it is recognised

Particle meets antiparticle and converts to other particles

Electron-positron annihilation as the main example

Pair production is the reverse; general destruction and Sufi fana are other senses

Related models

is a kind of - in registry terms

process

is a kind of - in physics

particle interaction

is reverse of - the inverse process

pair production

is used in - medical imaging

positron emission tomography

In practice

Families and kinds

electron-positron annihilation

proton-antiproton and other pair annihilation

annihilation in colliders

positronium decay

annihilation in astrophysics and dark matter searches

fana as a Sufi concept, a separate sense

Standards and regulation

Radiation safety rules for PET imaging

No regulation of the process itself

Failure modes and hazards

Confusing senses of annihilation

Popular misconceptions about antimatter

Radiation exposure in imaging

Also called

electron–positron annihilationpair annihilationFana

Where this came from

wikidata · CC0 1.0

Drafted structure

Bundle to layer to finding to question, as the second pass will find it: 4 bundles · 8 layers · 8 findings · 16 questions.

Physics What annihilation is.

Science.

Definition

Definition and conservation.

Definition

Definition.

  1. What is particle annihilation, and what conservation laws govern it? definition
  2. Is the question about particle physics, general destruction or the Sufi concept? boundary

Examples

Examples.

Examples

Examples.

  1. How does electron-positron annihilation proceed, and what other annihilations occur? definition
  2. Which entry fits the specific process? action
Apply Applications.

Application.

PET

Medical imaging.

PET

PET.

  1. How does positron emission tomography use annihilation photons? provenance
  2. Which entry fits positron emission tomography? action

Colliders

Colliders and research.

Colliders

Colliders.

  1. How are annihilation reactions used in particle colliders and in dark matter searches? provenance
  2. Which references are standard? provenance
Theory Theory and antimatter.

Theory.

QED

Quantum electrodynamics.

QED

QED.

  1. How does quantum field theory describe annihilation? provenance
  2. Which entry fits quantum electrodynamics? action

Antimatter

Antimatter.

Antimatter

Antimatter.

  1. What is antimatter, and why does the universe contain so little of it, with findings attributed? provenance
  2. Which sources are cited? provenance
Context Other senses and history.

Context.

Senses

Other senses.

Senses

Senses.

  1. What is fana in Sufi thought, and how does general usage of annihilation differ from physics? provenance
  2. Which entry fits fana? action

History

History.

History

History.

  1. How was annihilation predicted by Dirac and observed after the discovery of the positron? provenance
  2. Which entry fits the history of particle physics? action

What the second pass must settle

  • Should electron-positron annihilation be the primary entry?
  • How should physics references be linked?
  • The registry entry has merged an alias for the Sufi concept fana; should it be split off?