More complex than we thought? Cosmologists set to question the standards of how we view the universe

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This week, some of the world's leading cosmologists will come together at the Royal Society in London to evaluate the important question: what if this basic assumption that the universe is a vast, evenly speckled expanse with no notable features is wrong?

A conference of leading cosmologists at London's Royal Society is set to challenge the conventional view that the universe is a vast, evenly speckled expanse with no notable features. This view, a fundamental pillar of the standard model of cosmology, has been the basis for understanding the Big Bang and the evolution of the universe over the past 13.7 billion years.

What if we're wrong?

This week, some of the world's leading cosmologists will come together at the Royal Society in London to evaluate the important question: what if this basic assumption is wrong?

The meeting will last two days, from April 15th (Monday) to April 16th (Tuesday).

Cosmologist Prof Subir Sarkar of the University of Oxford, a co-organiser of the meeting, as per the Guardian said that recent high-profile astronomical observations have cast doubt on this basic assumption of uniformity across the universe.

These observations include evidence suggesting that the universe is expanding more quickly in some regions than others. It also hints at megastructures in the night sky, and cosmic flows - vast celestial rivers of material that challenge conventional theories.

"We are, in cosmology, using a model that was first formulated in 1922," said Sarkar, adding that it is so deeply ingrained that it is treated as "the religion".

"We have great data, but the theoretical basis is past its sell-by date. More and more people are saying the same thing and these are respected astronomers," he added.

One finding presented at the conference by Dr Nathan Secrest of the US Naval Observatory suggests that the universe may be slightly lopsided. Analysing a catalogue of over 1 million quasars (extremely luminous galactic cores), his team found that one hemisphere of the sky appeared to host roughly 0.5 per cent more sources than the other.

If confirmed, this discrepancy could undermine the basis for dark energy, which is supposed to be the dominant component of the universe.

"It would mean that two-thirds of the universe has just disappeared," remarked Sarkar.

The expanding universe

Dr Konstantinos Migkas of Leiden University will also share findings that the rate at which the universe is expanding, known as the Hubble constant, appears to vary across space. This suggests that observations do not match predictions of the standard model at a local scale, adding "another problematic piece to the puzzle," said Migkas.

PhD student Alexia Lopez of the University of Central Lancashire has discovered cosmic megastructures, named Big Ring and Giant Arc, traced out by galaxies and galaxy clusters on a scale beyond which the universe should be smooth and featureless. These structures challenge the assumption that the universe is homogeneous on large scales.

"When we're finding a list of structures that are exceeding this scale, are they challenging this assumption that is so fundamental in cosmology?" 

"Maybe there needs to be more of a critical analysis of our standard model," said Lopez. 

However, some scientists, like Prof George Efstathiou of the University of Cambridge, remain sceptical of these findings. At the conference, he will present his take to the scientific community. He said that while people accuse him of defending the model "they don't realise is how much time I've spent trying to disprove it. I completely disagree that's there's some kind of groupthink."

As Prof Wendy Freeman, presenting new findings from the James Webb Space Telescope, puts it, there are "tantalising threads at varying levels of significance" that require further exploration to understand where, "if at all, the standard model breaks down."

(With inputs from agencies)

Moohita Kaur Garg

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