The whole thing is retarded. I'll just mention one thing. Some people are referring to a "multiverse" meaning the existence of a large number of (finite-sized) different parts of the same (infinite) space-time that are cut off from each other because they can't be reached from each other by a path that always travels at or below the speed of light.
Others are referring to the alternative realities in Everett's interpretation of a quantum measurement, where the world splits in two so that both outcomes of a measurement occur and both parts of the wavefunction, written as a sum, have an interpretation in reality. Whenever someone asks Michio Kaku about the first one, in the context of it being used as a bodge to excuse string theory being shit, he starts blabbing about the second one, so we know he doesn't understand it, doesn't care he doesn't understand it, and is happy to bullshit to other people about things he doesn't understand.
If you point this out, his herd of nigger-cattle pop up to claim "You're an elitist who doesn't like people explaining things to the public". If someone asks a question, and some supposed authority replies with gibberish with no relation to the truth, that is not an explanation, and objecting to it shows respect for the public's desire to understand, the opposite of what is claimed. It is Kaku who doesn't like people explaining things to the public, because he fills them full of bullshit that makes it harder, in fact essentially impossible, to understand what is actually going on.