Gravitational waves may be related to the existence of life on Earth

A group of English researchers argue that molecules found on Earth and important for life originate in phenomena involving gravitational waves.

Collision of neutron stars are important in the production of important elements for human life.
Collision of neutron stars are important in the production of important elements for human life.

One of the greatest discoveries of this century was the observation of gravitational waves by the LIGO observatory in 2015. The discovery was a milestone in the history of Astronomy and Science by giving a Nobel Prize to the person responsible for the project, physicist Kip Thorne. These phenomena enable one more way to observe the Universe.

The idea of gravitational waves comes since Albert Einstein introduced general relativity where mass distorts space-time. Everything that has mass can generate gravitational waves but the interest is in compact objects that could produce waves intense enough for observation. These compact objects would be black holes and neutron stars.

A group of researchers from King's College London submitted an article where they argue that gravitational waves would be associated with our existence. In the article, they study processes that form molecules that are associated with life on Earth. These molecules would be formed through collision of neutron stars that are related to gravitational waves.

Gravitational waves

According to general relativity, mass distorts space-time causing what we know as the gravitational field. When an object with mass accelerates through space-time, gravitational waves are emitted. The analogy would be like a stone being thrown into a lake with standing water and waves being propagated in all directions.

In this way, gravitational waves can propagate through the Universe at the speed of light. Observing these phenomena is a challenge that requires laser interferometers that can measure variations on atomic scales. In 2015, gravitational waves were observed for the first time in history, earning a Nobel Prize in Physics for the discovery.

Neutron stars

Although the first observations are of black hole collisions, neutron stars are also sources of gravitational waves. Compact objects are excellent sources of gravitational waves since the distortions are more extreme. Often, these gravitational waves are emitted in the so-called binary of neutron stars.

In 2017, the first gravitational waves associated with a binary of neutron stars were observed by LIGO.

Neutron stars are remnants of massive stars that have reached the end of their life. These objects are extremely dense to the point that electrons and protons are pressed and form neutrons. Generally, neutron stars have a few kilometers in diameter but a mass similar to the mass of the Sun.

How are neutron stars related to life?

In the periodic table, many elements are associated with the life of stars as in the main sequence that there is the production of helium up to nitrogen and oxygen.Other elements are associated with the supernova that is the end of a star's life. Others are associated with collision of neutron stars.

Periodic table with the origin of each element.
Most of the elements of the periodic table have their production associated with an astronomical phenomenon. Credit: NASA

But two elements draw attention due to their importance for biological processes.Iodine is related to the production of hormones by the thyroid and bromine associated with the production of collagen. Both biological processes are important for the maintenance of human life and are key parts in health.

Other elements, such as uranium proṕrio, have a slightly more indirect relationship with human life. Uranium plays an important role in the habitability of planet Earth associated with tectonic activity. In other words, it is indirectly related to the maintenance of the climate on Earth.

What about gravitational waves?

The elements are produced in the collision of neutron stars that happen when two of these objects spiral towards each other. In energy conservation, objects should orbit indefinitely if there is no loss of energy during evolution. And it is at this point that gravitational waves are important.

While neutron stars orbit, a part of the energy is lost in the form of gravitational waves. When they lose energy, the stars begin to spiral into smaller and smaller orbits and approach. In the end, the stars collide producing the essential elements for life. The end result is possibly a black hole.


Ellis et al. 2024 Do we Owe our Existence to Gravitational Waves? arXiv.