I'm 32 and today was the first time I've heard the expression 'upset the apple cart' used. It was on reddit and the context was:
"Once again, my colleague Stephen Hawking has upset the apple cart. The event horizon surrounding a black hole was once though to be an imaginary sphere. But recent theories indicate that it may actually be physical, maybe even a sphere of fire. But I don't trust any of these calculations until we have a full-blown string theory calculation, since Einstein's theory by itself is incomplete."
Looking it up I found that it means to 'cause trouble, by spoiling ones plans' or 'to disorganize something, especially established plans.'
So, my question is: is there an implied meaning behind this idiom?
Does it mean that Stephen Hawking is basically talking a bunch of smack that goes against the established theory of whatever they're talking about and causing trouble because it gets a lot of press, thus, upsetting the apple cart?
Or rather, that there is some established theory, but Stephen Hawkings brilliant ass self came up with something that is making them reconsider whatever it is they'[re talking about, thus, upsetting the apple cart.
Or third, is it just impossible to tell without further context.