2) A definite geographical area is not necessary for society. It is universal and pervasive; but, a definite geographical area is essential for a community.
Regarding the explanation above, when we say the following, after all I am wondering which geographical area is to be considered. That is, I can not see any area, however, Could you??
The academic community
The reason you can't think of a defined geographical area for "academic community" is that there isn't one. The term "community" is not restricted to people living in a defined geographical area; that's a part of one definition of the word, but there are other definitions that are more about shared characteristics.
That definition is only correct if you are referring to concrete communities, such as a neighborhood. More abstract communities don't need a geographical location. The word 'community' implies that its members are linked together through a shared interest or belief, and that it is separate from the larger group. Within a 'society', you will find many 'communities'.
Think of a 'society' as a school and a 'community' as your field of study within the school: one is always smaller than the other, and so you are more familiar with the people in the smaller group.
