40273
Unlike the uncombined protons and electrons , these newly conceived atoms could not scatter the thermal radiation by Thomson scattering , and so the universe became transparent instead of being an opaque fog .
 person: Thomson
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: location, person, organization 
Text: {0} 
 Entities: Thomson 
Answer:
 person: Thomson