The role played by statistics in mechanics and by extension in thermodynamics as a whole, was prominently established by Clerk Maxwell, Gibbs, Boltzmann and their contemporaries. They explained the functions of heat in thermodynamic equations as statistical elements, which made it easier to interpret the results. Probabilistic mathematics found a stronger foothold in physical sciences and even gave birth to an offshoot of this subject, known as Statistical Physics. Statistical mechanics finds modern day applications as well, for instance in game theory, and real life scenarios such as algorithms for traffic signals.
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This is probably the groundwork on which most of modern physics developed into the gargantuan user manual to the universe and how it works. Einstein theorized the special theory of relativity in two parts; one, that the laws of physics are applicable on all bodies that are not in acceleration; and two, that the speed of light in vacuum is the same for all observers, regardless of the motion of the source of the light. These two fundamentals laid the foundations for furthering studies relating space and time, matter and energy, eventually led to the invention of atomic bombs.
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