Physics 09 - The Uncertainty Principle

Two years passed. Heisenberg 'laid another egg'. He declared that it is impossible to know the precise position of a particle such a moving electron, and its precise momentum at the same instant. Momentum is velocity multiplied by mass of the particle. The more precisely the position of the particle is measured, the less precisely it is possible to measure its momentum. The equation he developed to describe the uncertainty involved Planck's constant. It is a known fact that observing an object entails allowing photons, electrons or any other particles or waves of energy to strike it. So, the very act of observing a particle affects the observation. But Heisenberg's next revelation was even more startling. He asserted that an electron does not have a definite position or path until we observe it. This is feature of our universe, he opined, not merely some defect in our observing or measuring ability. Great Malayalam poet of yesteryears Kumaran Aasan wrote much before Heisenberg: ഒരു നിശ്ചയമില്ലയൊന്നിനും വരുമോരോ ദശ, വന്നപോലെ പോം. And his contemporary poet and philosopher Nalapatt Narayana Menon (great grand uncle of poet Kamala Das) had written: അനന്തമജ്ഞാതം അവർണ്ണനീയം ഈ ലോകഗോളം തിരിയുന്ന മാർഗ്ഗം അതിങ്കലെങ്ങാണ്ടൊരിടത്തിരുന്നു നോക്കുന്ന മർത്ത്യൻ കഥയെന്തു കണ്ടു!