On the other hand, if you want a general heuristic that could’ve led Fermi to do better, I would suggest reasoning that previous-historical experimental proof of a chain reaction would not be strongly be expected even in worlds where it was possible, and that to discover a chain reaction to be impossible would imply learning some new fact of physical science which was not already known.
It’s wise to consider how non-hindsight might have been harder. It’s even wiser to consider, for each training example, what general heuristics might’ve helped anyway.
I think the comments have done a good job showing that learning that a chain reaction was possible would have also implied new facts of physical science, e.g. about neutron emission of the available isotopes, so the heuristic in the OP doesn’t help much.
Yes. Essentially, “they were still the default projection from what was already known.” was dramatically untrue at the time of 10% assessment, when it was not known that any neutrons are produced in fission, or any similar processes. And once it became true, Enrico Fermi did rapidly do a very difficult calculation of the neutron multiplication factor, and concluded that self sustaining chain reaction is possible.
The imaginary world where people of Enrico Fermi calibre are unable to follow simple steps due to the extreme conclusions, is a shared fantasy of many, many crackpots.
I think the comments have done a good job showing that learning that a chain reaction was possible would have also implied new facts of physical science, e.g. about neutron emission of the available isotopes, so the heuristic in the OP doesn’t help much.
Yes. Essentially, “they were still the default projection from what was already known.” was dramatically untrue at the time of 10% assessment, when it was not known that any neutrons are produced in fission, or any similar processes. And once it became true, Enrico Fermi did rapidly do a very difficult calculation of the neutron multiplication factor, and concluded that self sustaining chain reaction is possible.
The imaginary world where people of Enrico Fermi calibre are unable to follow simple steps due to the extreme conclusions, is a shared fantasy of many, many crackpots.