The activation energy barrier separates reactants from products. The top of the barrier is the transition state. Putting the right amount of energy into the reaction allows the reactants to surmount the barrier. Occasionally, the particle can appear in the probability area on the other side of the activation barrier. In effect, hydrogen "tunnels" through the activation barrier. Particles of different energies tunnel at various heights. The thinner barrier at the top promotes tunneling, but few particles have sufficient energy at these heights.
In the early years of the 20th century, a new theory, quantum mechanics, revolutionized physicists' understanding of nature. But delving into the subatomic realm meant rethinking some fundamental assumptions: Here, information passes instantly between particles; protons can be in two places at once; and hydrogen can defy classical conservation of energy.
Today, researchers use quantum mechanics to refine their understanding of the physical laws governing life. A ...
