Q1 Who believes in many-worlds?

"Political scientist" L David Raub reports a poll of 72 of the "leading cosmologists and other quantum field theorists" about the "Many-Worlds Interpretation" and gives the following response breakdown [t].

1) "Yes, I think MWI is true" 58%
2) "No, I don't accept MWI" 18%
3) "Maybe it's true but I'm not yet convinced" 13%
4) "I have no opinion one way or the other" 11%
Amongst the "Yes, I think MWI is true" crowd listed are Stephen Hawking and Nobel Laureates Murray Gell-Mann and Richard Feynman. Gell-Mann and Hawking recorded reservations with the name "many-worlds", but not with the theory's content. Nobel Laureate Steven Weinberg is also mentioned as a many-worlder, although the suggestion is not when the poll was conducted, presumably before 1988 (when Feynman died). The only "No, I don't accept MWI" named is Penrose.

The findings of this poll are in accord with other polls, that many- worlds is most popular amongst scientists who may rather loosely be described as string theorists or quantum gravitists/cosmologists. It is less popular amongst the wider scientific community who mostly remain in ignorance of it.

More detail on Weinberg's views can be found in _Dreams of a Final Theory_ or _Life in the Universe_ Scientific American (October 1994), the latter where Weinberg says about quantum theory:
"The final approach is to take the Schrodinger equation seriously [..description of the measurement process..] In this way, a measurement causes the history of the universe for practical purposes to diverge into different non-interfering tracks, one for each possible value of the measured quantity. [...] I prefer this last approach"

In the The Quark and the Jaguar and Quantum Mechanics in the Light of Quantum Cosmology [10] Gell-Mann describes himself as an adherent to the (post-)Everett interpretation, although his exact meaning is sometimes left ambiguous.

Steven Hawking is well known as a many-worlds fan and says, in an article on quantum gravity [h], that measurement of the gravitational metric tells you which branch of the wavefunction you're in and references Everett.

Feynman, apart from the evidence of the Raub poll, directly favouring the Everett interpretation, always emphasized to his lecture students [f] that the "collapse" process could only be modelled by the Schrodinger wave equation (Everett's approach).

[f] Jagdish Mehra The Beat of a Different Drum: The Life and Science Richard Feynman
[h] Stephen W Hawking Black Holes and Thermodynamics Physical Review D Vol 13 #2 191-197 (1976)
[t] Frank J Tipler The Physics of Immortality 170-171