In the currently selected work area, is it possible to reference fields in a record that is not the currently selected record?

If so, how?

If not, what is/are the conventional means for constructing a logical expression that references the same field in two different records of a table. (I can think of some ways, I'd like to know what others do and whether there is a generally accepted method)

for example, I want to test

IF alias.fname@index(n) = alias.fname@index(m) ....

....

Where '@index(x)' is my psuedo-subscript that corresponds to physical (RECORD) or logical (INDEX) order depending upon my requirements.