Einstein: Relativity theory reaffirmed – One of the most difficult space tests

Once again confirmed the theory of General Relativity of Einstein, as he passed another test in the universe. After watching a pair of neutron stars (pulsars) move around each other for 16 years curving space-time, a large international team of astronomers concluded that the behavior of the two stars is consistent with Einstein’s theory. For over a century various scientific groups have tried to find error in general relativity, but have failed, although their efforts are to continue, as any crack in this theory will open new avenues in Physics.

The theory, published in 1915 bringing real revolution in Physics, describes the effects of gravity in spacetime. If something has a very large mass – as in the case of pulsars – it curves space-time around it more than something with a smaller mass. This means that in neutron stars – which have an extremely high density of matter and emit radio waves from their poles – the light must be noticeably curved around them, as photons are forced to follow curved spacetime, something that can be observed from Earth. In fact, when two pulsars “dance” around each other, then they accelerate and also emit gravitational waves (wrinkles of spacetime), which at the same time pushes their trajectory to shrink, as they gradually lose energy.

Einstein’s Theory of General Relativity: What emerged from observations between 2003-2019

Scientists from Europe, Australia and the US, led by the professor Michael Kramer of the German Max Planck Institute for Radio Astronomy in Bonn, who published the publication in the journal Physical Review, multiannual observations (2003-2019) of the pulsar pair PSR J0737-3039A/B, which is at a distance about 2,400 light-years from Earth. The two stars are so dense that although they have about 30% more mass than the Sun, their diameter does not exceed 24 km.

The two neutron stars – estimated to eventually collide in 85 million years – complete one orbit around each other in in just 147 minutes, animated with unimaginable speeds of up to one million kilometers per hour. At the same time the pulsars rotate like a whirlpool around their axis, completing one 44 revolutions per second, while the other, which is slower, one rotation every 2.8 seconds. Every time a pulsar rotates, a ray of radio waves reaches the Earth, conveying the impression that it is “pulsating” (hence its name).

Using seven ground-based radio telescopes in various parts of our planet, scientists have found that pulsar radio pulses reach Earth later than expected and this is because they are delayed by the large curvature of the space-time of the two stars. Calculations have shown that the delay is 99.99% explained by Einstein’s theory of relativity, as transmitted by APE-MPE.

“It’s about the most rigorous test to date of Einstein’s theory and sets the bar for future experiments in terms of accuracy. General relativity is the best theory we have about gravity, but we know, due to its incompatibility with quantum mechanics and the established model (of particle physics), that it is not the last word. Finding the slightest deviation from general relativity will be a major discovery that will open a window into a new Physics. “beyond our current understanding of the universe and can ultimately help us discover a unified theory of the fundamental forces of nature,” he said. Robert Ferdman of the University of East Anglia.

“We will return to the future using new radio telescopes and new data analysis, hoping that we will eventually identify some weakness in general relativity, which will lead us to an even better gravitational theory,” said the associate professor. Adam Deler of the Australian Swinburne University of Technology.

Here you will see the relevant scientific publication.