A Physics Model for Origin of Life

TL;DR

This paper presents a physics-based model using quantum tunnelling to estimate the probability of life originating on Earth, concluding that extraterrestrial life in the universe is extremely unlikely.

Contribution

It introduces a novel physics-only approach to estimate the origin of life, emphasizing quantum mechanics' role and suggesting life's rarity in the universe.

Findings

Quantum tunnelling significantly increases the probability of life's origin.

The probability of extraterrestrial life in the universe is effectively zero.

Life's emergence is an exceedingly rare event according to the model.

Abstract

In this article, we attempt to convince the reader that the origin of life was such an exceptionally unlikely event that it probably has never occurred elsewhere. This involves an explicit calculation using the laws of physics which, while speculative, may encapsulate the essential science without knowledge of biological details. Making only physics, and no biology, assumptions about the origin of the first single celled organism (SCO) on Earth, we adopt methods of quantum tunnelling to make an estimate of the probability ${\cal P}_{SCO}$ for the origin of life. We argue that before the time $t_{SCO}$ laws of physics must suffice and assume a first-order phase transition which nucleates at the first SCO production. In the classical limit where Planck's constant vanishes $h\rightarrow0$, ${\cal P}_{SCO}$ also vanishes and remains extremely small for the correct value of $h$. Thus quantum mechanics plays a central role in permitting life to form. We compare the resultant probability with the expected number of exoplanets in the Milky Way ($\sim10^{12}$) and the Visible Universe ($\sim10^{24}$) and conclude that the probability of extraterrestrial life in the Visible Universe is infinitesimal. This result suggests that the visible universe is a lonely place for humankind because extraterrestrial life will never be encountered.