Science feature on ancient medicine filling empty pages (8,7)

'science' is the definition.
(particle physics is a kind of science)

'feature on ancient medicine filling empty pages' is the wordplay.
'feature on' becomes 'article' (a newspaper feature. I am not sure about the 'on' bit.).
'ancient medicine' becomes 'physic' (historical term for medicine).
'filling' indicates putting letters inside.
'empty' means to remove the middle letters.
'pages' with its middle removed is 'ps'.
'article'+'physic'='articlephysic'
'articlephysic' placed inside 'ps' is 'PARTICLE PHYSICS'.