Quantum physics

[Stephen Raj]

Main Question or Discussion Point

Why can't energy is absorbed by protons rather than by electrons when a light ray strikes the atom.

 

[guerom00]

Hi,

Light is absorbed when there is an excited state to go to.
You can picture a proton as the ground state of the (uud) 3-quarks system. The first excited state of this system (if it exists at all… I don't know…) is very high in energy and unreachable by photons with “reasonnable” energies

 

[RougeSun]

Protons can absorb photons too but it's easier for an electron to absorb it because it can move around

 

[jtbell]

Nuclear energy levels are measured in MeV (millions of electron volts), whereas photons of visible light have energies of only a few eV.