In a word: no. The only way to change unit ranges is with upgrades, and that only works on the units they apply to. With triggers you can have somebody research a technology as follows -
New Trigger
(name trigger if you want)
(New condition if applicable)
New Effect
-Research Technology
--(Insert Tech Here)
--(Insert Player Here)
Hope that helped!
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Do not ask for whom the bell tolls, it tolls for thee...