Who says the world is 4.6 billion years old?

Answer 1

Every scientist that has looked objectively at the data relating to the Earth's age has come to the same conclusion that the age of the Earth must be of the order of 4.6 billion years.

Early, flawed, estimates of the age of the Earth came from such methods as calculating the rate of cooling of the Earth from an original molten state, or the rate of salination of the seas. these methods gave estimates in the range of 20-100million years. We now know that these methods gave values that were to low because they failed to take into account, for example, the heating of the Earth from radioactive decay processes.

Modern methods of aging the Earth are based on radioactive decay. Knowing, for example:

- the amount of argon in a potassium-bearing rock

- that Argon is a product of potassium-40 decay

- the half-life for the radioactive decay of potassium-40

- that a molten rock would allow the argon to escape

allows us to calculate a minimum for the age of rock since it was molten and, hence, calculate the minimum time that has elapsed since the Earth itself was molten. Similar ideas are used to give the age of Uranium- or Thorium-bearing rocks from their lead content. These methods give a minimum age for the Earth of around 4.6 billion years.

The evidence from the amount and rate of formation of rock strata, the consistency of the fossil record with the rate of species formation and the age of the earth and whole set of other astronomical and planetary observation data all indicate that the 4.6 billion year age is correct.

Unless some Earth-shattering data appears, a person would have to ignore so much evidence to give a figure that it is very much different from this that it would be impossible to sustain that position in a logical and scientific discussion.