What is the meaning of "person specification" in a job advert? I am going to submit my application to a postdoc in math. In support of my application, I have been asked about what I can do, and they have mentioned that

You should pay particular attention to the person specification as you will only be shortlisted if you can demonstrate that you meet all of the essential criteria.

But I do not know exactly what they mean by the above mentioned statement? Can I provide a brief description of my scientific background and its relation to the advertised project?
There exists a brief description of the project, including the area of research.
I've seen this terminology particularly in the UK, though I don't know how widespread it is. In each of the UK jobs I've seen with this phrasing, the &quot;person specification&quot; was a very clearly labelled part of the advertisement for the opening, or in some cases a separate PDF document. It contained a bulleted list of items clarifying both &quot;essential&quot; and &quot;desirable&quot; qualifications for the position.
I think your contact is urging you to consult such a list. If you have not gotten your hands on this kind of document regarding the position, look carefully for it where the job was advertised. If you still can't find it, I would write back and ask for a copy or where you can find one.
If part of your written materials for the application includes a personal statement, that statement should briefly highlight specific aspects of your background which demonstrate that you fulfill the listed items. Frankly I'd reference the specific items on the list.
I have not personally done job recruiting, but it is my impression a literal checklist of whether these items appear in your application will be made.