
What is Heisenberg's Uncertainty Principle? - ColinWright
http://www.theguardian.com/science/2013/nov/10/what-is-heisenbergs-uncertainty-principle?CMP=twt_fd
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downer98
Passages like this absolutely convince me that, while physicists can certainly
tell you they are familiar with certain observable phenomenon, the reality is
that they don't have clue about the realities of the phenomena they observe:

    
    
      Alpha particles are two protons and two neutrons emitted 
      by some heavy nuclei, such as uranium-238. Usually these 
      are bound inside the heavy nucleus and would need lots of 
      energy to break the bonds keeping them in place. But, 
      because an alpha particle inside a nucleus has a very 
      well-defined velocity, its position is not so well-
      defined. That means there is a small, but non-zero, chance 
      that the particle could, at some point, find itself 
      outside the nucleus, even though it technically does not 
      have enough energy to escape. When this happens – a 
      process metaphorically known as "quantum tunneling" 
      because the escaping particle has to somehow dig its way 
      through an energy barrier that it cannot leap over – the 
      alpha particle escapes and we see radioactivity.
    

They're just making things up and declaring it science.

    
    
      The temperatures at the core of the sun are not high 
      enough for the protons to have enough energy to overcome 
      their mutual electric repulsion. But, thanks to the 
      uncertainty principle, they can tunnel their way through 
      the energy barrier.
    

Magic! We know it must happen, so let's make up an idea to explain it, and
worry about its plausibility and accuracy later.

    
    
      These "virtual particles" appear in pairs – an electron 
      and its antimatter pair, the positron, say – for a short 
      while and then annihilate each other. This is well within 
      the laws of quantum physics, as long as the particles only 
      exist fleetingly and disappear when their time is up. 
      Uncertainty, then, is nothing to worry about in quantum 
      physics and, in fact, we wouldn't be here if this 
      principle didn't exist.
    

Translation: Due to the premise that we are terrestrial beings bound to this
planet, who can never know a true vacuum, and regardless of our efforts to
shield our experiments, are at the mercy of randomly occurring cosmic rays,
let's just repurpose the word "vacuum" to suit our needs, rather than chase an
unattainable set of conditions.

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ColinWright
I don't know a lot of Quantum Physics, but I do know more than most people
(not hard) and I'm having a hard time reconciling what you say with what I
know. To help me get some context, can you tell me your own background in QM?

How much of the math do you really know, and how much are you relying on
"common sense" and popular descriptions?

The reason I ask is that these passages you quote are pretty much exactly in
accord with QM as I know it, and QM as I know it is used to predict lots of
stuff very accurately. As a result, QM as I know it seems to be useful. Your
condemnation of it seems misplaced, so I'd be interested to know more about
where it (your condemnation) comes from.

