"He says the speed of light fluctuates"
He never says this. He says the measurements fluctuate, which means the speed of light itself may (or may not) fluctuate. But we will never know because it's been defined as a constant.
He never says this. He says the measurements fluctuate, which means the speed of light itself may (or may not) fluctuate. But we will never know because it's been defined as a constant.