Steam digester Torricelli and further developed by German scientist Otto von Guericke with his Magdeburg hemispheres. Guerike's demonstration was documented by Gaspar Schott, in a book that was read by Robert Boyle. Boyle and his assistant Robert Hooke improved Guericke's air pump design and built their own. From this, through various experiments, they formulated what is called Boyle's law, which states that the volume of a body of an ideal gas is inversely proportional to its pressure. Soon the ideal gas law was formulated. Based on these concepts in 1679 a Boyle's associate, named Denis Papin, built a "bone digester", which is
Electron degeneracy pressure temperature. Electrons are part of a family of particles known as fermions. Fermions like the proton or the neutron follow Pauli's principle and Fermi–Dirac statistics. In general, for an ensemble of non-interacting fermions, also known as Fermi gas, each particle can be treated independently with an energy given by the purely kinetic term, where is the momentum of one particle and its mass. Every possible momentum state of an electron within this volume up to the Fermi momentum being occupied. The degeneracy pressure at zero temperature can be computed as where "V" is the total volume of the system and