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Research by a team of European physicists could explain why the universe did not collapse immediately after the Big Bang.

Studies of the Higgs particle suggested that the very early accelerating universe should have been unstable - and scientists have been trying to work out why this was not the case.

But this latest study suggests that the Higgs boson may have actually interacted in gravity in such a way that enabled the universe to survive.

Physicists from Imperial College London say gravity saved the early universe (evolution of the cosmos shown). They say it interacted with the Higgs boson to provide stability 13.8 billion years ago. It was thought the Higgs particle should have made the cosmos unstable, but gravity helped to provide stability

Physicists from Imperial College London, and the Universities of Copenhagen and Helsinki believe this simple explanation could explain the beginning of the universe. 

In the new study in Physical Review Letters, the team describe how the spacetime curvature - in effect, gravity - provided the stability needed for the universe to survive expansion in that early period 13.8 billion years ago.

The team investigated the interaction between the Higgs particles and gravity, taking into account how it would vary with energy.

And they showed that even a small interaction would have been enough to stabilise the universe against decay.

'The Standard Model of particle physics, which scientists use to explain elementary particles and their interactions, has so far not provided an answer to why the universe did not collapse following the Big Bang,' explains Professor Arttu Rajantie, from the Department of Physics at Imperial College London.

'Our research investigates the last unknown parameter in the Standard Model - the interaction between the Higgs particle and gravity.

'This parameter cannot be measured in particle accelerator experiments, but it has a big effect on the Higgs instability during inflation.

'Even a relatively small value is enough to explain the survival of the universe without any new physics!'

The Higgs boson's role is to give the particles that make up atoms their mass. The particle was confirmed in 2012 using the Large Hadron Collider - pictured - the highest-energy particle collider ever made, built by the European Organisation for Nuclear Research (Cern)

The team plan to continue their research using cosmological observations to look at this interaction in more detail and explain what effect it would have had on the development of the early universe.

In particular, they will use data from current and future Esa missions measuring cosmic microwave background radiation and gravitational waves.

'Our aim is to measure the interaction between gravity and the Higgs field using cosmological data,' said Professor Rajantie.

'If we are able to do that, we will have supplied the last unknown number in the Standard Model of particle physics and be closer to answering fundamental questions about how we are all here.'