19th century : Electron, discovered by J. J. Thomson and his team 20th century : The theory of electrons and the Lorentz ether theory by Hendrik Lorentz 20th century : The discovery of the Zeeman effect by Pieter Zeeman 20th century : Photon, theoretically proven by Albert Einstein 20th century : Quantum theory to account for the photoelectric effect by Enrico Fermi, Max Planck, Niels Bohr, Albert Einstein, and others. 20th century : The discovery of superconductivity by Heike Kamerlingh Onnes 20th century : Transuranium element by Enrico Fermi. 20th century : Technetium, discovered by Emilio G. Segrè 20th century : The theories of special and general relativity by Albert Einstein 20th century : The demonstration of time dilation as a real physical phenomenon by Albert Einstein 20th century : Ultra short radio waves by J. C. Bose 21st century:Confirmed existence of Higgs Boson 21st century: Confirmed existence of Time Crystal 21st century: Confirmed existence of Gravitational Waves