desde que el mundo es mundo

Question

Here is the text:
"No creo que nunca haya habido uno peor que yo desde que el mundo es mundo."
My translation:
"I don't believe there was ever one worst than me since the beginning of time."

Question:
1. Does "desde que el mundo es mundo" mean "since the beginning of time"? Is this a common idiom?
2. Is the literal translation: "since that/(when) the world is world"

Answer 1

Here is the text:

"I don't believe there was ever one worst than me since the beginning of time."

"I don't believe [that] there was ever one worse than me since the beginning of time."

funnier that; not funniest than

better than; not best than

worse than; not worst than

the superlative doesn't work here

you are right, I didn't notice the author had made a mistake, no wonder it sounds a bit funny.

Answer 2

Here is the text:

"No creo que nunca haya habido uno peor que yo desde que el mundo es mundo."

My translation:

"I don't believe there was ever one worst than me since the beginning of time."

Question:

1. Does "desde que el mundo es mundo" mean "since the beginning of time"? Is this a common idiom?

2. Is the literal translation: "since that/(when) the world is world"

How about?
I don't believe there has ever been anyone/one worse than me since the world comes into existence.

Answer 3

Here is the text:

"I don't believe there was ever one worst than me since the beginning of time."

"I don't believe [that] there was ever one worse than me since the beginning of time."

funnier than; not funniest than

better than; not best than

worse than; not worst than

the superlative doesn't work here

got you mister p'liceman!

Answer 4

Here is the text:

"I don't believe there was ever one worst than me since the beginning of time."

"I don't believe [that] there was ever one worse than me since the beginning of time."

funnier that; not funniest than
better than; not best than
worse than; not worst than
the superlative doesn't work here

Answer 5

Here is the text:

"No creo que nunca haya habido uno peor que yo desde que el mundo es mundo."

My translation:

"I don't believe there was ever one worst than me since the beginning of time."

Question:

1. Does "desde que el mundo es mundo" mean "since the beginning of time"? Is this a common idiom?

2. Is the literal translation: "since that/(when) the world is world"

Yes, you got it! It is a commom Spanish idiom.
"Since when" is the literal translation.

I think also "as long as I can remember" means the same.