The image reveals the secret of the best science fiction book cover illustrations of the last century: a blue sphere, encased in a blue sphere with a dark black interior, encased in a blue sphere with a dark black interior, against a background of stars.
This drawing is the closest human imagination can get to the so-called Nestar, a hypothetical cosmic body that scientists mentioned for the first time last weekend. In the trade magazine Classical and quantum gravity.
It's a fascinating idea, the kind that will make fans of speculative basic science salivate, but will inevitably make the rest of the world shine. A star is a star, wrapped in a star, wrapped in a star, etc., as if it were a kind of Russian Matryoshka doll. This would be completely impossible with ordinary stars – which, for example, are not hollow inside – but it is possible with a star filled with dark energy.
That dark energy is a mysterious “something” that physicists once offered to explain why the universe continues to expand. Think of it as a kind of cosmic bicycle pump that drives expansion. In this case, the “bike pump” would be located in the star and pumping a cavity into it.
This brain-bending idea is more than just a random fantasy. In their professional article, the authors show that such a star is actually a correct result of the equations of Einstein's theory of general relativity, the precise theory that had also previously been used to predict, for example, the existence of black holes and gravitational waves — things that have been shown to actually exist — and wormholes. , tunnels through space and time, which have not yet been found, but are very popular in professional literature
This means that, at least from the point of view of physics, there is probably nothing preventing the existence of the star. Even if such a strange compact star turns out to be a mathematical error, or a sparkle that appears in equations without being a reflection of real reality, its study is still interesting. Only because such theoretical games can lead to new insights into adjacent areas of research, such as the search for the true nature of black holes.
In addition, as one of the authors himself said In the press release From Goethe University: “It is remarkable that even a hundred years after the first solutions of Einstein's field equations in general relativity, new solutions can still be found.” It's a bit like discovering a gold coin on a path that many others have already walked.
Whether that coin turns out to be an unexpected treasure or just a mirage, one thing seems certain: in the overwhelming vastness of the universe, there are undoubtedly many equally strange things waiting to be discovered.
Finished by the author
Georg van Hal is the scientific editor of the Volkskrant newspaper. He writes about astronomy, physics, and space travel. Van Hal published books on everything from the universe to the smallest, most basic elements of reality.