New Study Suggests Gravitational Waves May Have Created Dark Matter
A new study suggests that faint, ancient ripples in spacetime may hold the key to one of physics’ greatest mysteries.
Gravitational waves may have played a role in creating dark matter during the universe’s earliest moments, according to a new study by Professor Joachim Kopp of Johannes Gutenberg University Mainz (JGU) and the PRISMA++ Cluster of Excellence, in collaboration with Dr. Azadeh Maleknejad of Swansea University.
Published in Physical Review Letters, the study introduces new calculations that describe a previously unexplored way dark matter could have formed, involving so-called stochastic gravitational waves.
This work addresses a central question in particle physics: what makes up the universe. Everyday objects such as planets, stars, and living organisms consist of visible matter, yet this accounts for only about four percent of the cosmos. The rest is largely unseen, made up of dark matter and dark energy.
Dark matter alone represents about 23 percent of the universe. Observations show it is spread throughout space, shaping galaxies and the largest cosmic structures. Despite its widespread influence, the fundamental particles that make up dark matter remain unknown. Scientists continue to investigate this mystery through both theoretical models and experimental searches.
A new method for particle formation
Gravitational waves are ripples in spacetime typically produced by extremely energetic events, such as collisions between black holes or neutron stars. In contrast, stochastic gravitational waves arise from a range of processes that do not involve massive astronomical objects.
These weaker waves contribute to a background signal that fills the universe. Many of them date back to the earliest stages of cosmic history. They may have formed during events such as phase transitions of matter as the universe cooled after the hot Big Bang, or from primordial magnetic fields.
“In this article, we investigate the possibility of gravitational waves – which are believed to have been ubiquitous in the early universe – being partially converted into dark matter particles,” Kopp explained. “This leads to a new mechanism of dark matter production that has not been researched before.”
From Waves to Particles
The researchers propose that gravitational waves could have produced massless or nearly massless fermions. Fermions include familiar particles such as electrons, protons, and neutrons.
According to their model, these early particles later gained mass and evolved into the dark matter that still exists today.
“The next step in developing this line of research is to go beyond our analytical estimates and conduct numerical calculations to improve the accuracy of our predictions. Another avenue for future research is the investigation of further possible effects of gravitational waves in the early universe. One example for this would be a mechanism that could account for the well-known difference in particles and antiparticles produced,” said Kopp.
Source: SciTechDaily
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New Study Suggests Gravitational Waves May Have Created Dark Matter