Physics make quantitative statements about natural phenomena. Quantitative statements can be formulated less ambiguously than qualitative descriptions, which are based on words. Statements can be expressed in the form of predictions in the sense that the trajectory of a particle or the outcome of a process can be anticipated. If an experiment can be designed to test this prediction unambiguously, we say that the statement is experimentally testable. Quantitative statements are validated or falsified using quantitative measurements and experiments.
Physics is the experimental, quantitative, and predictive science of matter and its interactions.
Pictorially, physics progresses by putting specific questions to nature in the form of experiments; surprisingly, if they are well-posed, they result in concrete answers. that are robust and repeatable for an arbitrary number of times by anyone who can do the same experiment. This method of generating knowledge about nature, by using experiments to ask questions of it, is unique in the history of humankind and is called the scientific method. The scientific method has been at the core of all technological progress since the time of the Enlightenment.
Physics deals with matter at various scales and levels of granularity, ranging from macroscopic matter like galaxies, stars, planets, stones, and projectiles, to the scale of molecules, atoms, hadrons, quarks, and gauge bosons. There are four fundamental forces at the core of all interactions between all forms of matter: gravity, electromagnetism and two types of nuclear force: the weak and the strong. According to quantum field theory, all interactions in the physical world are mediated by the exchange of gauge bosons. The graviton, the boson for gravity, has not yet been confirmed experimentally.
