State

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Corresponding Wikipedia article: State of matter

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Five phases or states of matter, in ancient times called the “elements”

Element	State	Essence	Comment
Aether	Radiation	Photons, ideal gas.	Traditionally it’s not considered as a state of matter.
Fire	Plasma	Almost an ideal gas.	The difference between the gas and the plasma is as small as between green and blue colors.
Air	Gas	Real gas or a compressible “liquid”.
Water	Liquid	Uncompressible real “gas”.
Earth	Solid	Crystal.	The difference between matter and photons is as small as between red and violet colors.

The knowledge level of the modern natural science decreases as moving up in the above table. The solid mechanics and the fluid dynamics are the most researched areas. The plasma and aether physics are the least researched areas.

The weak intermolecular bonds are based on a non-chemical electromagnetic interaction. The consequences of these bonds are:

• Viscosity and friction.
• Gases are not ideal.
• Surface tension of liquids and their crystal structures (clusters).

The crystals are the real solids. The amorphous flexible solids are in fact the dense viscous liquids. The polycrystalline solids are the combinations of real and amorphous solids.

The body state depends on the average energy of the body particles, i.e. mainly on the temperature in case of the thermodynamic equilibrium.

	State (phase)
	Solid	Liquid	Gas, plasma
Retaining force	crystal bonds	surface tension	electrostatic, nuclear
Temperature	Т < TMELT	TFREEZ < Т < TBOIL(P)	TCOND(P) < Т < ТION(P), ТION(P) < T
Pressure	mechanical stress	static and dynamic
Density	mainly proportional to the temperature		thermodynamic (statistical) parameters
Molar heat capacity	depends on the molecular structure, temperature and state

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