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Elementarpartikel

Fra den gr�ske oldtid havde man en ide om, at alt stof bestod af noget udeleligt, som p� gr�sk kaldes atomos - heraf navnet atom. De blev da, i princippet, klassificeret som elementarpartikler (det g�r de ikke mere).

Omkring �r 1900 bestod universets atomer af de subatomare partikler; elektroner, protoner og neutroner. De blev da klassificeret som elementarpartikler. Det g�r de ikke mere, da fysikerne op igennem 1900-tallet har opdaget flere hundrede forskellige subatomare partikler som ikke best�r af elektroner, protoner eller neutroner.

I dag har partikelfysikkens forskere pr�vet at finde en bedre model for stof og den hedder Standardmodellen. I Standardmodellen best�r stof af 6 kvarker, 6 antikvarker, 6 leptoner, 6 antileptoner. Disse 24 partikler antages i dag at v�re stofs elementarpartikler.

Herudover eksisterer der ogs� f�lgende kraftformidlende elementarpartikler: gravitoner, fotoner, W-bosoner, Z-bosoner, gluoner, Higgs. Gravitonen og Higgs partiklen er hypotetisk partikler, da de endnu ikke er eksperimentielt p�vist.

Elementarpartikler kan klassificeres i:

Elementarpartikel
- Fermioner, stofpartikler (Har spin 1/2, 3/2, 5/2,...).
  - baryoner (kan "f�le" den st�rke kernekraft).
    - Kvarker: u-kvark, d-kvark, c-kvark, s-kvark, t-kvark, b-kvark og deres antipartikler.
  - leptoner (kan ikke "f�le" den st�rke kernekraft).
    - elektron, myon, tauon, elektronneutrino, myonneutrino, tauonneutrino og deres antipartikler.
- Bosoner, kraftpartikler (Kraftformidlere) (Har spin 0, 1, 2,...).
  - (gravitoner, fotoner, W-bosoner, Z-bosoner, gluoner, mesoner, Higgs)

Table of contents

1 Stofpartikeltabel
2 Kraftpartikeltabel
3 Se ogs�
4 Eksterne adresser

Stofpartikeltabel

Udover tabellens, findes der ogs� 12 antipartikler:

Familie	partikel	Masse·c²	el.lad/\|e\|	Baryontal	Vekselvirkning
1. Familie	Elektron (e)	511 keV	-1	0	Gr, em, svage
	Elektron-Neutrino (ν_e)	<2 eV	0	0	Gr, svage
	Up-kvark (u)	4 MeV	2/3	1/3	Gr, em, svage, st�rke
	Down-kvark (d)	7 MeV	-1/3	1/3	Gr, em, svage, st�rke
2. Familie	Myon (μ)	0,1 GeV	-1	0	Gr, em, svage
	Myon-Neutrino (ν_μ)	<0,2 MeV	0	0	Gr, svage
	Charm-kvark (c)	1,5 GeV	2/3	1/3	Gr, em, svage, st�rke
	Strange-kvark (s)	0,15 GeV	-1/3	1/3	Gr, em, svage, st�rke
3. Familie	Tau (τ)	1,8 GeV	-1	0	Gr, em, svage
	Tau-Neutrino (μ_τ)	<0,02 GeV	0	0	Gr, svage
	Top-kvark (t)	174,0 GeV	2/3	1/3	Gr, em, svage, st�rke
	Bottom-kvark (b)	4,7 GeV	-1/3	1/3	Gr, em, svage, st�rke

Kraftpartikeltabel

(I parentes: Formodede partikler, som endnu ikke er eksperimentielt p�vist):

Partikel	Masse·c²	Spin/(h/2π)	el.lad/\|e\|	formidlet vekselvirkning
Foton	0	1	0	elektromagnetiske kraft
Z⁰	ca. 91 GeV	1	0	svage
W⁺	ca. 80 GeV	1	1
W^-	ca. 80 GeV	1	-1
Gluon	0	1	0	st�rke (Farvekraft)
(Graviton)	0	2	0	Gravitation
(Higgs)	mellem ca. 60 GeV og ca. 540GeV	0	0	-----

Se ogs�

Universet udg�res af elementarpartikler og vakuum. Partiklerne er fordelt uj�vnt og partiklerne og partikelklynger ben�vnes forskelligt afh�ngig af t�thed og m�ngde; klyngerne sp�nder lige fra subatomare partikler til sorte huller.

En m�ngde af partikelklynger i vakuum er:

Galakse relaterede artikler:

Aktiv galakse (Seyfert, Kvasar, Blazar) | M�lkevejen

Stjernerelaterede artikler incl. typer og stadier:

Stjernebegivenheder:

Supernova | Hypernova

Mindre himmellegemer:

Planet | M�ne | Komet | Meteoroide (meteor, meteorit, ildkugle) | Sm�planet (asteroide, planetoide)

Rumfart, rumrejse:

Andre emner:

Eksterne adresser

particleadventure.org: The Standard Model, Unsolved Mysteries. Beyond The Standard Model, What is the World Made of? The Naming of Quarks (God popul�r fremstilling p� engelsk).
quarkdance.org ("Nuttede" dansende kvarker med musik)
Fundamental particles: quarks and leptons - Science-Park.info
University of California: Particle Data Group
particleadventure.org: Particle chart
CERNCourier: Season of Higgs and melodrama
6 December, 2001, BBCNews: 'God particle may not exist Citat: "...its giant accelerator which should have shown up the presence of the Higgs found absolutely nothing - and this could mean particle physics having to revisit some of its most cherished ideas..."
- 10 March, 2004, BBC News: 'God particle' may have been seen Citat: "...If correct, Dr Renton's assessment would place the elusive particle's mass at about 115 gigaelectronvolts...However, there is a 9% probability that the signal could be background "noise"..."
Milo Wolff: The Physical Origin of Electron Spin - using quantum wave particle structure Citat: "...The electron's structure, as well as its spin, had been a mystery. Providing a physical origin of spin for the first time is the purpose of this paper....note that spin, and other properties, are attributes of the underlying quantum space rather than of the individual particle. This is why spin, like charge, has only one value for all particles...This structure settles a century old paradox of whether particles are waves or point-like bits of matter. They are wave structures in space. There is nothing but space. As Clifford speculated 100 years ago, matter is simply, "undulations in the fabric of space". ..."
Robert Rutkiewicz: Explaining Particle Spin
Robert Rutkiewicz: Defining Mass Citat: "...The value of mass is not being redefined. But the concept of mass being a fundamental property is reviewed...A new physical law is postulated: All known particles are elements of momentum moving at a velocity c...This extension is based on special relativity and uses SR equation for mass..."
The Physical Origin of Electron Spin - using quantum wave particle structure Citat: "...note that spin, and other properties, are attributes of the underlying quantum space rather than of the individual particle. This is why spin, like charge, has only one value for all particles...."
Glimpses of a new paradigm. K.V.K. Nehru Citat: "...Dewey B. Larson introduces the new paradigm that motion is the basic and sole constituent of the physical universe, and space-time is the content—not the container—of the universe...", Dewey B. Larson (1898-1990)
8 January 2004, PhysicsWeb: Muons continue to defy Standard Model Citat: "..."The fact that our measurement continues to deviate from theory may be an indication that we are seeing new physics beyond the Standard Model," said Lee Roberts of Boston University..."