The Structures of Atoms are Engineered Precisely for Life to Exist
"The force of gravity must be fine-tuned to allow the universe to expand at precisely the right rate (accurate to within 1 part in 1060). The fact that the force of gravity just happens to be the right number with "such stunning accuracy is surely one of the great mysteries of cosmology." - physicist Paul Davies
Everything in the universe is made of atoms, from the stars in the farthest heavens to the cells in the human body. The atom itself is a bundle of "lucky coincidences." Within the atom, the neutron is just slightly more massive than the proton, which means that free neutrons can decay and turn into protons. If the proton that was larger and had a tendency to decay, the very structure of the universe would be impossible.
A free proton is simply a hydrogen atom, and if free protons had a tendency to decay, everything made of hydrogen would decay. The sun, which is made of hydrogen, would melt away. Water, a liquid oxide of hydrogen (H2O) would be impossible. In fact, the universe itself would decay, since about 74 percent of the observed universe consists of hydrogen.
There is no physical cause to explain why the neutron is larger. It is simply a fact. So apparently the only "reason" for the difference in size is that it allows the universe to exist and to support life.
Atomic particles also have an electrical charge. Electrons have a negative charge, and protons have a positive charge. Yet because the charge of the proton exactly balances that of the electron, most of the objects we encounter in daily life have no electrical charge.
If the electron carried more charge than the proton, all atoms would be negatively charged. In that case - since identical charges repel - all the atoms composing all the objects in the universe would fly apart in a catastrophic explosion. On the other hand, if the proton carried more charge than the electron, all atoms would be positively charged - with the same disastrous consequences.
Although the two particles differ from one another in all other respects (size, weight, magnetic properties, etc.), there is no known physical reason, no natural explanation, for the precise balance in the electrical charges of the proton and the electron. And since there is no natural explanation, no natural law to account for this extraordinarily precise adjustment, is it not reasonable to conclude that this intricate arrangement is the product of a choice, a plan, a design?
The slightest tinkering with the values of the fundamental forces of physics - gravity electromagnetism, the strong and weak nuclear forces - would have resulted in a universe where life was utterly impossible. The Anthropic principle states that in our own universe, all these seemingly arbitrary and unrelated values in physics have one strange thing in common: they are precisely the values needed to get a universe capable of supporting life."
