The beginning of quantum mechanics took place from the moment when the discoveries of new radiations took place and the mysteries were unveiled hitherto unknown in the spectrum of thermal radiation, defining heat in two ways, absorbed heat and heat emitted by a body.
The study of thermal radiation led Robert Kirchhoff, a German physicist, to propose two laws, which contributed richly to the study of the subject. Are they:
• Relationship between body temperature and emitted radiation.
• Introduction to the concept of blackbody radiation
In the first law, Kirchhof proposes that the radiation emitted from the body is caused by the state of agitation of the particles, molecules or atoms of the body, which due to this thermal agitation produce radiation electromagnetic.
In the second law, he introduces the black body, responsible for turning it into an object that emits thermal radiation, easy to carry out in practice, which has become indispensable for physics.
But quantum mechanics was, in fact, born from the moment when the physicist Max Plack, desperately, reversed the process of analyzing blackbody radiation. This happened because the radiation emitted by a black body generated very intense radiation, thus generating graphs for different temperatures.
Planck wanted, in a mathematical way, to show how it was possible to arrive at such graphs, but starting from the functions known in classical physics it was impossible to arrive at graphs, so he had the idea of starting from graphs and then arriving at the correct mathematical function, and when he found it, he based himself on Boltzmann's theories of thermodynamics, for then justify it.
Planck was able to transform a purely mathematical equation into a function with physical meaning, and as a result, Plack's constant, represented by the letter h, was born.
Planck's theory was postulated in order to show that in nature there is only energy in discrete values in how much action, giving nature a discontinuous and unacceptable result for classical physics known until then.
By Talita A. angels
Graduated in Physics
Brazil School Team
Modern physics - Physics - Brazil School
Source: Brazil School - https://brasilescola.uol.com.br/fisica/o-nascimento-mecanica-quantica.htm