Simplify the following text for a Grade 14 native English-speaking person.
Original: In 1988 Fert discovered the Giant magnetoresistance effect ( GMR ) in multilayers of iron and chromium which is recognized as the birth of spintronics ; GMR was simultaneously and independently discovered by Peter GrÃ 1\/4 nberg from the JÃ 1\/4 lich Research Centre .
Simplified: In 1988 Fert discovered Giant magnetoresistance ( GMR ) in iron and chromium which began spintronics ; GMR was also discovered by Peter GrÃ 1\/4 nberg from the JÃ 1\/4 lich Research Centre but Peter GrÃ 1\/4 nberg did not work with Professor Fert .