Crystals with no defects

What are the chances that one or another theoretical study wiU be a success As history shows, it greatly depends on whether theorists can think of a nice, manageable model idealizing the real world. Of course, there are no ideally simple systems in nature. However, we can use our imagination and invent an ideal gas (whose molecules do not interact at all), an ideal crystal (with no defects at all to the regular atomic structure), and so on. As a matter of fact, you can say that all these models are ideal indeed, meaning that they are the best for physicists. This is because they are the simplest — but they are simultaneously the most basic ones. So one has to master them first, before moving any further in either statistical mechanics, or hydrodynamics, or solid state physics, or whatever chapter of physics. 

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