Chapter 22
What is a Measurement?

This is what an observer does. An observation converts potential into reality and assigns a result. Sometimes a single accurate result depending on the quality of the measurement. It used to be that we thought all measurements were independent from what was being measured and did not influence them. Like measuring the length of a rod with a ruler. The rod always had a certain fixed length regardless of its measurement. Modern science now thinks differently because experiments are made on the tiniest of objects (Te) and it is often not possible to discover some property of that object without interacting with it in some way. This may cause a slight change in the objects state.

Of course accuracy is paramount in these modern experiments although not all measurements do give a single result, and not all measurements can provide an exact answer, no matter how good the quality of the equipment or experimenter. This is the case when the measurement is made on things that must obey the uncertainty principle.

We saw earlier in the section on that principle that at angular momentum levels of h, which is an incredibly small number, individual pairs of components like energy-time and momentum-distance can be slightly elastic or blurred provided they are reciprocal and yield the same product of h/2 or h depending on whether the particle has mass or not. One of the components in each pair can rise while the other falls. It is only their total that matters, and this total is half of Planck’s Constant if the particle has mass. Otherwise it is h for photons.

For instance it may be required that we know how long an energy transition takes for a single electron, or where another electron is when it has some momentum. No experiment will give a result with a fixed value in either of these cases. Only the electron’s spin can be measured accurately, and this will be h/2. Thus if the energy transition is small it will take longer to measure or occur than a larger transition which must happen quickly. This means that the smaller transition implies a lower frequency outcome (longer period), while a larger energy change involves a higher frequency wave to carry that greater energy away. Likewise for momentum and position: More accuracy in one means less accuracy in the other.

Other than this measurement is not such a complex topic.

The Origin of Everything
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