From: julio@diegidio.name   
      
   On Sunday, 4 September 2022 at 19:54:28 UTC+2, richali...@gmail.com wrote:   
   > On Saturday, September 3, 2022 at 7:15:37 PM UTC-5, ju...@diegidio.name   
   wrote:   
   > > On Saturday, 3 September 2022 at 15:50:03 UTC+2, Thomas Koenig wrote:   
   > > > Julio Di Egidio  schrieb:   
   > > > >   
   > > > > And *reversibility* itself is already present in classical physics,   
      
   > Thank you for your detailed response. I have to debate some points where   
   > I think you are being inconsistent.   
      
   Even if you disagree or don't see the point, that doesn't make   
   what I said (which is anyway just basic QM) inconsistent.  In   
   fact,  below you are repeating exactly the same mistakes as   
   in your opening post.  So, I'll just repeat quickly:   
      
      
   > but the  wave function calculated is not real.   
      
   That *depends* on your ontological stance: and your choice,   
   which is the standard one, is the one that is *most* problematic.   
      
   > The difference is "collapse". Take the two slit experiment with   
   > a single photon. When a photon is detected on the screen [...]   
   > If you try to start from this state and compute backwards [...]   
   > The backward computed wave function includes many   
   > possible sources   
      
   When the photon is detected, that is a *measurement*, i.e.   
   (standardly) you have *collapsed* the wave function, aka   
   the state: and *that* operation is not reversible, not QM!!   
   Conversely, do not collapse the wave function (consider   
   the joint system observer/observed) and you stay quantum   
   and have reversibility.   
      
   > QM is not deterministic in that at any given moment there   
   > are several possible mutually exclusive future outcomes.   
      
   Yes, it is: you are still conflating classical outcomes with   
   the evolution of the wave function, aka the quantum state.   
      
   > to me that this means that information is not conserved   
      
   Sure, but it's *collapse* that destroys information.   
      
   > Is there an error in my reasoning here?   
      
   Only if you'll insist...  :)   
      
   HTH,   
      
   Julio   
      
   --- SoupGate-Win32 v1.05   
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