Physics

Nature scatters clues across the scene¹. The detective, moving from a first overall look to an ever finer analysis, forms hypotheses, tests them against the evidence, drops some and forms new ones, until the case takes shape, becomes coherent and self-consistent, and earns the dignity of a theory. But the culprit is clever enough to slip away, and does so in the subtlest way. On the one hand it forces the investigator to sharpen the tools of analysis to catch ever more hidden and complex details; on the other, that very sharpness reveals subtle contradictions in the theory, which sometimes lead to major corrections or even to abandoning it. In some ways, though in a much simplified form, this is what a physicist does and how scientific theories are built.

It would be a real crime if those who study physics missed the fascination of this search for truth, or never came into conscious contact with the fertile and revolutionary ideas about the structure and workings of the Universe that physics has produced.

Then there is the question of language. Physics and the other exact sciences express their theories in an unambiguous language built on rigorous logical deduction: mathematics. Some people are still surprised that nature can be described mathematically, and is therefore, in a sense, mathematical itself. Perhaps, more realistically, the credit goes to our intelligence and its remarkable ability to invent such effective and refined tools for analyzing and describing reality.

Nobel laureate Richard P. Feynman called Euler’s formula e^iθ = cos θ + i sin θ “our jewel” and “the most remarkable formula in mathematics”². Had we never arrived at that splendid equation, we might never have felt the need to probe the mysteries of the universe so deeply³.

This section collects physics topics as interactive lessons, notes and anything else that helps in studying and absorbing its concepts. Some lessons also appear in other sections: physics is a fundamental science, and therefore a cross-cutting one.