alt Hacker News"Ether" is a hypothetical substance with certain properties. The Michelson-Morley experiment proved that no substance with those properties existed. There's something else with different properties, so it makes perfect sense to use a different name.
"Ether" is a hypothetical substance with certain properties. The Michelson-Morley experiment proved that no substance with those properties existed. There's something else with different properties, so it makes perfect sense to use a different name.
In context of approximately everyone's education, the history goes like this: in the past people believe there's something in empty space, and used the name "ether" for that. You learn that, then you learn that MM showed there's no "something", no "ether", but that empty space is, in fact, empty, which is what "vacuum" means. And then if you pay attention or any interest to the topic, you learn that there in fact is no pure vacuum, there's always "something" in empty space.
The obvious question to ask at this point is, "so ether is back on the table?".
Turns out the mistake is, as GP said, thinking MM proved space is empty; it only disproved a particular class of substances with particular properties. But that's not how they tell you about it in school.