On Fri, Jan 10, 2025 at 6:13 PM Quentin Anciaux <[email protected]> wrote:
> Le ven. 10 janv. 2025, 07:58, Bruce Kellett <[email protected]> a > écrit : > >> That is just patent nonsense. Formal tools are quite capable of giving >> the right answer for the realized world; (and the right answer is what >> actually happens.) >> >> I agree that formal tools can provide correct predictions for the > realized world. However, in a single-history framework, the "right answer" > they provide—the actual outcome—reduces probabilities to mere retrospective > descriptors. > Nothing retrospective about it. The probabilities are predictors of future outcomes. Probabilities only have meaning if the ensemble of possibilities they refer > to has some grounding, even if not directly realized. Otherwise, we are > attributing significance to calculations about scenarios that never existed > and had no potential to exist within the single-history paradigm. > But the essence of the probability is that we calculate the probabilities that these alternatives might become actual. > For example, if in this single-history universe, a particular outcome > (e.g., rolling a four on a die) never occurs, then retroactively, its > probability was effectively zero. > Bullshit. The prior probability does not change, even if the outcome was three rather than four. The formal tools used to calculate probabilities would still "predict" the > possibilities, but in a framework where only one history is ever realized, > those unrealized possibilities had no causal or explanatory connection to > the outcome. The tools become exercises in abstraction, detached from the > realized world. > > This is the crux of the issue: probabilities, in a single-history view, do > not reflect anything about what could happen—they only describe what did > happen after the fact. > Where did that queer idea come from? Without a substantive ensemble of possibilities, probabilities lose their > role as meaningful descriptors of potential and become post-hoc > justifications for a single outcome. In frameworks where possibilities are > real (e.g., many-worlds), probabilities gain coherence because they > describe distributions over actualized outcomes, not abstract, non-existent > alternatives. > > The point is not that formal tools fail to provide correct answers—they > do. The issue is that, in a single-history framework, the connection > between those tools and the nature of reality becomes tenuous, leaving the > probabilities they calculate feeling arbitrary and conceptually empty. > So it all boils down to what you had for dinner -- or what your guts feel. Physics is more than a matter of personal existential angst. Bruce -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion visit https://groups.google.com/d/msgid/everything-list/CAFxXSLTOMfRC%3DYRzb5Zpr%3DXunJAwTfo_VWr4KkL33%3D7V-AU-MA%40mail.gmail.com.
