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Scientists have long predicted that the Universe’s lifetime is effectively forever – specifically, 10¹¹⁰⁰ years.

But scientists from Radboud University have found that the Universe is decaying much quicker than previously thought, calculating that the last remnants of stars will perish in just 10⁷⁸ years instead.

“The ultimate end of the Universe comes much sooner than expected, but fortunately it still takes a very long time,” says Heino Falcke, black hole expert and lead scientist on the research.

The researchers arrived at this shorter timeframe by considering evaporation due to Hawking radiation.

Hawking radiation and the end of the Universe

Hawking radiation, proposed by Stephen Hawking in 1974, is a phenomenon where particles and radiation can escape from the immense gravitational pull of a black hole.

If a black hole is emitting particles and radiation, it means that over time it will decay.

Contentious among physicists, the theory implies a rare contradiction with Einstein’s theory of relativity, which suggests black holes can only grow. 

The 10⁷⁸ figure represents the time it would take for a white dwarf star to decay when considering the impact of Hawking radiation.

White dwarfs are the dense, final evolution of stars that aren’t big enough to form black holes or neutron stars, and represent the most long-lived objects in the Universe.

What will the end of the Universe look like?

But what does the end of the Universe look like?

Its ultimate fate is still unclear to scientists, but can be boiled down to three main candidates: freeze, crunch or rip.

The research by Falcke and his team fits into the Big Freeze picture: all the matter and energy in the Universe will eventually evaporate, spreading out into an endless, timeless void (or ‘heat death’).

That’s hardly a cheering thought, but it’s one that shouldn’t give us too much to worry about; 10⁷⁸ years is still vastly longer than the current age of the Universe from the Big Bang to today: 13.8⁹ years. 

The team hope to use this interdisciplinary study – which brought together mathematicians, quantum physicists and astrophysicists – to learn more about the Universe’s mysteries. 

“By asking these kinds of questions and looking at extreme cases, we want to better understand the theory, and perhaps one day, we will unravel the mystery of Hawking radiation,” concludes Walter van Suijlekom, co-author of the study.

A Universe reboot?

Words: Chris Lintott

Cheer up, there’s no need to let the sooner-than-expected decay of the last stellar remnants get you down!

Even when the cosmos is no more than a sea of expanding radiation and particles, we’ll still get to witness the never-before-seen and incredibly rare process of proton decay play out.

Only once the last proton goes pop will we reach the final state of the Universe.

But, like an ageing movie franchise, the story might not be over.

Some cosmologists believe our Universe might produce daughter universes.

So instead of being stuck in this decaying cosmos, we can jump across to a reboot and experience the exciting first 25 billion years or so again and again and again.

The research, led by the University of Bristol and published today in the journal Nature, also found a new mechanism associated with the chemical reaction which enables the shape of the compound to be flipped from being right-handed to left-handed by simply adding a common agent in the chemical reaction.

Study lead author Varinder Aggarwal, Professor of Synthetic Chemistry at the University of Bristol, said: “The findings change our understanding of the fundamental chemistry of this group of organic molecules. It presents exciting implications because the science allows us to make alternatives of the drug Tamoxifen, with potentially greater potency and less unwanted side effects.”

While most alkenes are easy to prepare, a specific type with four different parts – called tetrasubstituted alkenes – are much more challenging but used to make cancer-fighting medicines and natural products like essential oils.

So the research team aimed to find a more efficient method of making tetrasubstituted alkenes, including Tamoxifen, which allows them to be easily manipulated and adapted into different forms.

The new method offers a highly versatile solution to building complex complex tetrasubstituted alkenes from simple building blocks.

Prof Aggarwal explained: “Our original design plan used organic boronic esters as the key ingredient but that resulted in unstable intermediates, so didn’t work.

“We then tried a less common form of boron containing molecules, namely boranes and that’s when the clever molecular gymnastics became possible. This new boron system enabled the installation of different groups on the alkene in a controlled manner from very simple building blocks, like Lego.

“It’s so exciting because it holds the key to finding even better drug molecules – like alternatives to Tamoxifen – with more of the properties you want and less of what is undesirable, such as side effects.”

The scientists enlisted the help of computational chemists at Colorado State University to map exactly what was happening. That led to the full extent of their discovery being uncovered.

Co-author Robert Paton, Professor in Chemistry at Colorado State University, said: “The mechanism showed that by just changing the reaction conditions through adding an agent, the geometry of the alkene can switch direction from left to right. This was surprising and hadn’t been seen before.”

In addition to drug molecules like Tamoxifen, the researchers also worked with natural products such as γ-bisabolene, a fragrant compound found in essential oils, to demonstrate the broad applications of their breakthrough.

Prof Aggarwal added: “Now we have struck upon an effective, flexible methodology, it allows us to swap in other molecules so the potential here is wide-reaching for both drug discovery and materials science.”

The research was funded by the UK Research and Innovation (UKRI) Engineering and Physical Sciences Research Council (EPSRC).

Paper

‘Boron-Mediated Modular Assembly of Tetrasubstituted Alkenes’ by Varinder Aggarwal et al in Nature