> On 21 Dec 2018, at 03:22, Bruce Kellett <[email protected]> wrote: > > On Fri, Dec 21, 2018 at 1:03 PM Jason Resch <[email protected] > <mailto:[email protected]>> wrote: > On Thu, Dec 20, 2018 at 7:05 PM Bruce Kellett <[email protected] > <mailto:[email protected]>> wrote: > On Fri, Dec 21, 2018 at 11:45 AM Jason Resch <[email protected] > <mailto:[email protected]>> wrote: > 1. It is a prediction of eternal inflation and string theory. > > String theory and its "landscape" are very speculative, and unlikely to have > any relation to the real world -- there is no evidence that string theory is > even a coherent theory! Eternal inflation, although popular, is only one > possibility for inflation, and even inflationary theory itself is not > well-established science. > > I agree they are speculative, but they are on the side many many universes. > Meanwhile there is no evidence for "the only universe that exists is the one > I can see". > > The universe we see is the only one for which we have any concrete evidence, > and that evidence is indubitable.
That is of course a strong evidence for a physical reality, but unless we buy the Aristotelian theology, “seeing” is not an evidence for a metaphysical reality. I think the whole problem is here: a confusion for the evidence for physics with an evidence for a metaphysics. This has worked for 1500 years, only by terror, violence, and then habits, and the constant hiding of the (mind-body) problem under the rug (notably through “fairy tales”). Physics is a wonderful science, but to make physics systematically, without argument nor evidence, into a metaphysics is a form of “modern” charlatanism, when made consciously, and still a form of obscurantism when done by ignorance. With science, doubts are mandatory. Bruno > > > 2. There is no known principal that prohibits other systems ruled by > different laws. > > The idea that everything that is not forbidden must exist is a silly > metaphysical notion. > > > That's not the position I was advocating, though I think that notion is less > silly than the idea that we should expect to be in a position to see > everything that exists. > > Why? That is, in fact, all we have any direct evidence for. > > > 3. The digits of the dimensionless constants at significance levels not > important to life appear to be randomly distributed > > Appearances can be deceptive -- vide flat earth. > > > What do you think determines the dimensionless constants? > > They may not be determined by some theory. Or they may be determined by some > TOE. Who knows? > > > 4. It is highly surprising that the dimensionless constants hold the values > they do as if they were even slightly different, the universe would be too > simple for any life to exist > > How do you know that? > > > It is difficult to create systems that develop spontaneous complexity, as any > programmer could tell you. That our universe is such a system is surprising, > given that most systems do not yield spontaneous complexity. > > Look, the Bayesian prior for any argument about the nature of the universe is > that we exist. So there is nothing in the least surprising about the fact > that the universe we observe is compatible with our existence. Anything else > is just idle speculation. > > But that's not the correct prior to use. > > It is, you know. If you did not exist you could not be arguing about this. So > your existence must be part of any prior about the nature of the universe we > see. The prior must include total evidence available. > > Your assumption is that one and only one universe exists. > > That is all we have evidence for, but it is not so much an assumption as a > well-founded conclusion. > > Starting from that assumption you must then ask what is the probability that > life will exist in that one and only one universe. Given that the > probability is low, would suggest the initial assumption is wrong. Of the 26 > dimensionless constants, lets say each one had a 50/50 chance of leading to > catastrophe (no life) if in an invalid range. Then the probability that all > constants would be in the correct range is (1/2)^26 = 1 in 67 million. We > should then be (1 - (1/2)^26) sure that the universe we can see is not the > only one. > > That is fallacious reasoning, since we do not have any evidence that the > parameters were selected randomly from unknown distributions. > > Why do you believe there is only one inevitable possibility for the laws of > physics? I've never heard any justification for that idea. > > Why do you think I believe that? > > You seemed to reject the idea of other possible physical systems ruled by > different laws, and that the dimensionless constants are not from some random > distribution. > > I reject these notions because there is no evidence for them. And if you > assume this, it does not actually answer any questions, since you know that > the universe in which you exist must be compatible with your existence. > > > One idea about the end-point of physics is that there is a TOE that will > explain everything -- predict the values of all constants and so on, maybe > even specify a lot of the boundary conditions. Why do you believe that such a > TOE is not possible? > > I realize that is the dream of many physicists, but science has provided no > justification for the success that initiative, and substantial evidence that > such an initiative is doomed to fail (e.g., all the evidence of landscapes). > > There is actually no evidence for landscapes. These occur only in some > speculative, unevidenced theories. > > 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] > <mailto:[email protected]>. > To post to this group, send email to [email protected] > <mailto:[email protected]>. > Visit this group at https://groups.google.com/group/everything-list > <https://groups.google.com/group/everything-list>. > For more options, visit https://groups.google.com/d/optout > <https://groups.google.com/d/optout>. -- 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 post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/everything-list. 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