It looks like the Georgia Government Instructions for Lines 11a-c have a "Note: If you use the standard deducion on your Federal return, you must use the Georgia standard deduction on your Georgia return.

See page 11 of the 2018 IT-511 Individual Income Tax 500 and 500EZ Forms and General Instructions booklet.

https://dor.georgia.gov/sites/dor.georgia.gov/files/related_files/document/TSD/Booklet/IT-511/2018_I...