What Is The Universe Made Up Of ?

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• Baryonic Matter
 
- both luminous and dark
- pressureless
- gravitating

• Radiation
 
- radiation pressure
- gravitating

• Non-Baryonic Matter (eg. supersymmetry, massive neutrinos, axions)
 
- dark
- pressureless
- gravitating

• Vacuum / Dark Energy (eg. cosmological constant, quintessence)
 
- negative pressure
- gravitating

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borrill@nersc.gov  http://www.nersc.gov/~borrill

penugent@LBL.gov http://www.LBL.gov/~nugent