But this theory also had a fatal flaw. A positive nucleus with a negative electron orbiting around it, seen from the plane of the orbit, would appear as an oscillating electric dipole, as shown on the previous page. By all the laws of classical physics and electromagnetic theory, an oscillating electric dipole should radiate electromagnetic energy.

If this were not so, the whole theory behind wireless telegraphy and radio would be wrong. If the atom did radiate energy, however, then the electron would fall to a lower-energy orbit, closer to the nucleus. It would radiate still more energy, and the process should end only when the electron had whirled down and collided with the nucleus, as shown in lower left margin.

According to classical theory, every atom in the universe should long since have collapsed, because its electrons had spiraled into the nucleus. Thus whether electrons were stationary or orbiting, atoms should not exist. What was wrong with classical physics?