Groundbreaking research questions the shape of the Universe

For over a century, Einstein's general relativity has served as the cornerstone for explaining gravity across various scales, from our solar system to the vast expanse of the evolving universe. The assumption of an isotropic universe, where the underlying spacetime remains uniform in all directions, has been a fundamental aspect of this paradigm. The theory has often been likened to raisins in a loaf of bread which spread evenly further out as the bread bakes in an oven. This 100-year-old assumption, supported by NASA and the European Space Agency (ESA) satellites, greatly simplifies mathematical modeling and astronomical observations.

According to Dr Ó Colgáin, this new research suggests the expansion of the universe is not a perfect bubble type shape but has a less uniform look, bulging in different directions. "The isotropic Universe assumption has noticeable benefits. On one hand, it makes gravity equations easier to solve. On the other hand, astronomers can point telescopes in a single direction on the sky and assume findings are representative."

However, recent studies over the past decade, pioneered and pushed by members of the international collaboration, have uncovered a critical loophole in this long-standing assumption. While the cosmic microwave background (CMB) radiation, relic radiation from the big bang, has been confirmed as isotropic to good approximation, matter distributions—comprising atoms, electrons, and other building blocks of the universe—display unexpected anisotropic patterns.

Dr Eoin Ó Colgáin and his international colleagues have meticulously documented these surprising findings in a peer-reviewed publication in the esteemed journal Classical and Quantum Gravity. The paper builds the emerging science case supporting an anisotropic Universe. The findings have garnered significant attention, prompting the Royal Society London to schedule a debate on the topic in 2024.

Dr Ó Colgáin remarked, "The philosopher of science, Thomas Kuhn, separates science into normal science, marked by incremental advancements within a paradigm, and breakthroughs or paradigm shifts. Our emerging results raise the exciting prospect that a paradigm shift is on the horizon."

This research challenges established norms and invites the scientific community and the public to question the assumptions that have underpinned our understanding of the Universe for approximately 100 years.

Listen to Dr Eoin Ó Colgáin’s interview on ATU Podcast here.

Aidan Haughey 
ATU Communications Manager /
Bainisteoir Cumarsáide OTA
Ollscoil Teicneolaíochta an Atlantaigh (OTA), Éire
Atlantic Technological University (ATU), Ireland       
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