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I don't think the term is quite that bad, but the way we talk about it is. That said, my choice to use the term "puff" was specifically to avoid any pre-conceived notions about the duality.

The term "wave-particle duality" was coined because we can imagine waves, and we can imagine particles, and when we realised that we couldn't force light and electrons to be one or the other, that they must be, in some sense "both".

The term is not wave particle alternation, conversion, collapse, or any thing which implies that it is sometimes one and sometimes the other. However, the elementary examples we give people learning about QM might mislead people to believe that.

The "duality" is expressed specifically to indicate that it has both aspects at all times.

Close - you're mixing up the wavefunction of a puff of light with the wave-like nature of a puff of light.

The wavefunction gives you the probability distribution of any properties you want to measure.

The wave-like nature is what gives it colour and allows diffraction.

But the wave-like properties (wavelength, etc) are not the properties of it's position wavefunction.

You make reference to the electron double-slit experiment. It's tempting to think that electrons are particles - except that they're not. The fact that they exhibit the same "particle-wave duality" indicates that they too are "puffs" of matter, not particles, not waves, but something with properties of both.

There are no particles at quantum scale. Particles only exist at human scales. The struggle comes in accepting that the thing we are talking about is not analgous to any specific thing in our experience. It's convenient to talk about particles, and waves, because we can conceive of what they are. We imagine that particles are like incredibly small billiard balls, and waves are like ripples on a pond and that light is sometimes one and sometimes the other - because we can imagine these things. But puffs of light and puffs of matter don't behave like tiny billiard balls or tiny ripples - they behave like a combination of them. You can simultaneously measure both wave-like and particle-like behaviour.

Who's outlawing any words? I think we agree - I'm suggesting we need a new word, because the words we have (wave, particle) are perfectly good but don't describe the thing we want (nature of light)...

The wave-particle duality is not a quantum superposition like you're describing (which would break down under measurement), although the caricatured manner in which we teach it might lead you believe that. It's a little more simple than that.

In our world, we are used to two kinds of things: particles, and waves. We are used to this distinction, and describe most things in one of these manners. Sound is a wave, a billiard ball is a particle, vibrations are waves, bricks are particles. If something is a particle, it has certain properties, like position, size, and shape. If it is a wave, it has certain other properties like wavelength, frequency, and amplitude. In addition, there are some common properties like velocity and direction.

When it came to studying light (and many other quantum stuffs), we can't directly see what it's made of. But we can take measurements of each "puff" of light, and infer its properties that way. When we do this, we notice that puffs of light have some properties which are particle-like, and some which are wave-like. So the term "particle-wave duality" became popular to describe this new material that was behaving simultaneously like a particle and a wave. It doesn't make sense to ask which one it is - a "puff" of light is neither a particle, nor a wave, but a different kind of stuff which has some properties of each.

writing the article is a DIRECT response to being asked to provide estimates for ACTUAL WORK ... writing the article was most certainly done in lieu of that actual work...

.. assuming, of course, that the article wasn't written after the "actual work" was completed...

If you're storing the length, then "iterate over array and perform this operation" (for example, for a search or a "double every element" transformation) can use the known length to set up a for loop, rather than having to check "am I at the last element of the array" for every element... This could be a good reason to store the length even if you don't want the cost of bounds-checking.

(or what's the length for?)

Bounds checking is one option, but it could also be used for iteration.

Can you spin up a minimal VM and reproduce it? Then it could definitely use a bug report...

If you don't, I might try it in a few days when I get some breathing room.

I agree with you on the idea and behaviour of the control classes, but have generally found it handy to have some guarantees of well-formedness in the data objects.

Otherwise, every control object which uses the data object needs to verify every detail about the data object before it uses it - which leads to the duplication of validation code issue you were concerned about in the first place...

So if you are not doing your field validation at creation time, how do you enforce the "interface contract"?

Something somewhere has to verify that the address is a valid address, and the port is a valid port (why would you accept a socket request for port 67890?) - why allow a non-conformant data object to exist?

What domains have such wide-ranging field values that validated data is not a reasonable idea?

Data classes like this?

class TCPSocketAddress
{
private long ipaddress;
private int port;
 
string getAddress()
{
  return long2ip(ipaddress);
}
 
void setAddress(string addr)
{
  if (addr.matches("/^\d{1,3}.\d{1,3}.\d{1,3}.\d{1,3)$/")) ipaddress = ip2long(addr);
  else throw InvalidIPAddressException;
}
 
int getPort()
{
  return port;
}
 
void setPort(string addr)
{
  if (newport > 0 && newport < 65536) port = newport;
  else throw InvalidTCPPortException;
}
 
}

On the one hand I was confused how systemD was involved in the launch.

Then you haven't been paying attention - all the systemd supporters are adamant that it is descended from launchd!

That's partly because T-Mobile is basically a European phone company - they're the international arm of Deutsche Telekom...