<Tr> <Th> Nuclear physics </Th> </Tr> <Tr> <Td> Nucleus Nucleons (p, n) Nuclear matter Nuclear force Nuclear structure Nuclear reaction </Td> </Tr> <Tr> <Td> Models of the nucleus (show) Liquid drop Nuclear shell model Interacting boson model Ab initio </Td> </Tr> <Tr> <Td> Nuclides' classification (show) Isotopes--equal Z Isobars--equal A Isotones--equal N Isodiaphers--equal N − Z Isomers--equal all the above Mirror nuclei--Z ↔ N Stable Magic Even / odd Halo </Td> </Tr>

What is the principal difference between an infrared ray and a gamma ray