Einstein was right: Most of the universe is a strange ‘dark ...


Einstein was right: Most of the universe is a strange ‘dark fluid’

This mysterious fluid, which moves towards you as you push it away, solves the dark energy puzzle, say Oxford boffs

Sarah Knapton

The universe may be filled with a mysterious “dark fluid” that was predicted by Einstein more than 100 years ago, Oxford University scientists believe.
In 1917, Einstein suggested that the vacuum of space must contain sufficient energy to balance out the effects of gravity, which he called the cosmological constant, but by 1931 he had dismissed the idea as his “greatest ever blunder”.
Since the late 1990s scientists have believed that a combination of invisible dark matter and dark energy makes up 95% of the universe, keeping galaxies together, but have failed to find any direct evidence of either.
Now scientists at Oxford believe they have found a solution. In a new paper they suggest that dark energy and matter are in fact a single phenomenon – an invisible fluid that exists throughout the universe acting like a field of negative gravity.
In his notes on relativity Einstein wrote that for his cosmological constant to work empty space must somehow act as a balance to the effects of gravity, suggesting he realised it must be filled with some kind of negative mass.
Dr Jamie Farnes, of Oxford’s Department of Engineering Science, said: “We now think that both dark matter and dark energy can be unified into a fluid which possesses a type of ‘negative gravity’, repelling all other material around them.
“Although this matter is peculiar to us, it suggests that our cosmos is symmetrical in both positive and negative qualities.
“The outcome seems rather beautiful: Dark energy and dark matter can be unified into a single substance, with both effects being simply explainable as positive mass matter surfing on a sea of negative masses.”
Although there are a billion trillion stars in the universe, visible matter is extremely rare, making up just 5% of everything.
Dark matter was thought to be an invisible material that exerts a gravitational force on matter that is measurable, while dark energy is a repulsive force that makes the universe expand at an ever quicker rate.
The new theory suggests the two are actually one – a massive field of negative matter that repels everything around it, in the opposite way to how gravity draws things in.
The existence of negative matter had previously been ruled out because it was thought any material would become less dense as the universe expands, yet observations show that the impact of dark energy does not thin out over time.
However, Farnes believes that negative mass may be continually bursting into existence, replenishing itself.
When the properties of the new dark fluid were fed into a computer simulation, it accurately mirrored the formation of dark matter “halos” around galaxies, which keep them from flying apart from the centrifugal force of spinning matter.
Farnes now plans to test the theory using the new Square Kilometre Array (SKA), the world’s largest telescope in which Oxford is collaborating, and which is expected to be operational by 2022.
“If real, it would suggest that the missing 95% of the cosmos had an aesthetic solution: We had forgotten to include a simple minus sign,” he added.
“These effects may only seem peculiar and unfamiliar to us, as we reside in a region dominated by positive mass.
“The quest to understand the true nature of this beautiful, unified, and – perhaps polarised – universe has only just begun.”
The new model was published in the journal of Astronomy and Astrophysics.
– © Telegraph Media Group

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