Evidence · Case 08 · Science

The cosmological constant

One exhibit from the free evidence repository at apologetics.pro.

The energy of empty space, called the cosmological constant, is the sharpest example. The value we observe is smaller than naive theoretical estimates by a factor of about ten to the 120th power, a one followed by 120 zeros. That figure measures the mismatch between theory and observation, not the probability of life, and the estimates behind it are model dependent, so it is best read as a striking discrepancy rather than a calculated odds figure.

Sources

Geraint F. Lewis and Luke A. Barnes, “A Fortunate Universe” (opens in a new tab)
Geraint F. Lewis and Luke A. Barnes, “A Fortunate Universe: Life in a Finely Tuned Cosmos” (Cambridge University Press, 2016)

Objections & responses

The 1 in 10^120 figure compares the observed value with a naive quantum field theory estimate that everyone agrees is wrong. Doesn’t it measure our ignorance of how to calculate vacuum energy, not fine-tuning?: That is a fair technical point. The discrepancy is a famous unsolved problem, and physicists disagree about whether it is best described as fine-tuning or as a sign that the calculation is wrong. What is not in dispute is that if the constant were even modestly larger than observed, galaxies would not form; the life-permitting range is small on any account. Keep the two questions apart: why is it so small is an open puzzle, and it must be small for structure to exist is the fine-tuning point, and only the second is relied on here.

Appears under 1 claim in this case

Read it in context