Can there be a hyphen in "nonlinear"?
Solution 1:
According to Hyphenated Words: A Guide
You would not use a hyphen with the prefix non unless it is before a proper noun.
Do not hyphenate words prefixed by non, un, in, dis, co, anti, hyper, pre, re, post, out, bi, counter, de, semi, mis, mega, micro, inter, over, and under (among others).
Examples: nonaffiliated, nonemergency, uninfected, inpatient, disorder, disbar, coworker, copayment, antismoking, antimanagement, hyperactive, hyperrealism, preoperative, prejudge, reoccur, readjust, resubmit, postoperative, posttraumatic, outpatient, outmoded, bimonthly, biannual, counterrevolutionary, counterculture, decompress, semifinal, semiannual, misinformed, misprint, megabyte, microcircuit, interconnected, interoffice, overemphasize, override, underrepresent, underestimated.
EXCEPTIONS: When the second element is capitalized, as in Un-American and non-English, a hyphen is used. Also, occasional exceptions exist where the prefix and the second element have not (yet) "grown together," such as de-emphasize, pre-owned, co-op (to distinguish from coop) and anti-inflammatory (and all words with anti- prefix and second element beginning with i)
Solution 2:
The first three dictionaries I looked in all give nonlinear as the entry with no alternate non-linear. Here's NOAD:
nonlinear |nänˈlinēər| adjective
1 not denoting, involving, or arranged in a straight line.
• Mathematics designating or involving an equation whose terms are not of the first degree.
• Physics involving a lack of linearity between two related qualities such as input and output.
• Mathematics involving measurement in more than one dimension.
• not linear, sequential, or straightforward; random : Joyce's stream-of-consciousness, nonlinear narrative.
2 of or denoting digital editing whereby a sequence of edits is stored on computer as opposed to videotape, thus facilitating further editing.