β = - (1 / ρ)(∂ρ/∂T)ρ const
where
ρ density T Temperature
β measures the fractional decrease in fluid density as temperature increases at constant pressure.
... mayaa tatam idam sarvam jagad avyaktamuurtinaa | matsthaani sarvabhuutaani na caaham teshv avasthitah || -- Giitaa ...