The weak equivalence principle, a component of the theory of general relativity, has just passed its toughest test yet. (Image: ONERA).
” data-medium-file=”https://i0.wp.com/ensedeciencia.com/wp-content/uploads/2022/09/Low-Res_visuelPRL2.jpg.png?fit=300%2C168&ssl=1″ data-large-file=”https://i0.wp.com/ensedeciencia.com/wp-content/uploads/2022/09/Low-Res_visuelPRL2.jpg.png?fit=700%2C392&ssl=1″ class=”size-full wp-image-25471 jetpack-lazy-image” alt=”” width=”700″ height=”392″ data-recalc-dims=”1″ srcset=”https://i0.wp.com/ensedeciencia.com/wp-content/uploads/2022/09/Low-Res_visuelPRL2.jpg.png?w=700&ssl=1 700w, https://i0.wp.com/ensedeciencia.com/wp-content/uploads/2022/09/Low-Res_visuelPRL2.jpg.png?resize=300%2C168&ssl=1 300w” data-lazy-sizes=”(max-width: 700px) 100vw, 700px” src=”https://i0.wp.com/ensedeciencia.com/wp-content/uploads/2022/09/Low-Res_visuelPRL2.jpg.png?resize=700%2C392&is-pending-load=1#038;ssl=1″/><img data-lazy-fallback="1" data-attachment-id="25471" data-permalink="https://ensedeciencia.com/2022/09/14/la-teoria-de-la-relatividad-general-de-einstein-acaba-de-pasar-su-prueba-mas-estricta-hasta-el-momento/low-res_visuelprl2-jpg/" data-orig-file="https://i0.wp.com/ensedeciencia.com/wp-content/uploads/2022/09/Low-Res_visuelPRL2.jpg.png?fit=700%2C392&ssl=1" data-orig-size="700,392" data-comments-opened="0" data-image-meta=""aperture":"0","credit":"","camera":"","caption":"","created_timestamp":"0","copyright":"","focal_length":"0","iso":"0","shutter_speed":"0","title":"","orientation":"0"" data-image-title="Low-Res_visuelPRL2.jpg" data-image-description="" data-image-caption="
The weak equivalence principle, a component of the theory of general relativity, has just passed its toughest test yet. (Image: ONERA).
” data-medium-file=”https://i0.wp.com/ensedeciencia.com/wp-content/uploads/2022/09/Low-Res_visuelPRL2.jpg.png?fit=300%2C168&ssl=1″ data-large-file=”https://i0.wp.com/ensedeciencia.com/wp-content/uploads/2022/09/Low-Res_visuelPRL2.jpg.png?fit=700%2C392&ssl=1″ class=”size-full wp-image-25471″ src=”https://i0.wp.com/ensedeciencia.com/wp-content/uploads/2022/09/Low-Res_visuelPRL2.jpg.png?resize=700%2C392&ssl=1″ alt=”” width=”700″ height=”392″ srcset=”https://i0.wp.com/ensedeciencia.com/wp-content/uploads/2022/09/Low-Res_visuelPRL2.jpg.png?w=700&ssl=1 700w, https://i0.wp.com/ensedeciencia.com/wp-content/uploads/2022/09/Low-Res_visuelPRL2.jpg.png?resize=300%2C168&ssl=1 300w” sizes=”(max-width: 700px) 100vw, 700px” data-recalc-dims=”1″/>
Albert Einstein’s theory of relativity has passed a series of tests since it was formulated more than a century ago. Now, once once more it has just been proven correct with amazing precision.
Recently an incredible study by an international team of researchers presented the most accurate test yet of the Principle of Weak Equivalence, a key component of the theory of general relativity. This principle states that all objects (regardless of their mass) should fall freely in the same way in a given gravitational field when interference from factors such as air is removed.
A famous demonstration of the weak equivalence principle occurred during Apollo 15, when astronaut David Scott dropped a feather and a hammer at the same time on the lunar surface. Since there is (almost) no air resistance here, both objects fell towards the ground of the Moon at the same speed.
Similarly, though with extremely high precision, scientists carried out an experiment called MICROSCOPE, which tested the principle by measuring the accelerations of freely falling objects in a satellite orbiting the Earth.
The team launched the MICROSCOPE mission from 2016 to 2018, in which they measured the accelerations of objects in free fall on a satellite in orbit around the Earth. The results indicate that the accelerations of the pairs of objects did not differ by more than one part in 10^15, which rules out any violations of the Weak Equivalence Principle or deviations from the current understanding of general relativity at that level.
“We have new and much better constraints on any future theories, because these theories must not violate the equivalence principle at this level,” said in a statement Gilles Métris, scientist at the Côte d’Azur Observatory and member of the MICROSCOPE team.
Albert Einstein is one of the most famous scientists in history, and much has to do with his theory of general relativity, published in 1915. His theory describes how gravity works and its relationship with time and space. But since he does not account for observations of quantum phenomena, researchers look for deviations from the theory at ever-increasing levels of precision and in various situations. If in any of these senses the theory of relativity does not comply, it would mean that there are new interactions or forces that might unite relativity with quantum physics.
On the one hand, this is a plus point for the theory of relativity, and scientists can use it with more confidence than ever. However, this also places clear restrictions on the intersection between general relativity and quantum mechanics, which operate under different rules. In other words, it means that Einstein was right (and very right), but it takes away a chance for physicists looking for a unified theory.
The researchers say that this experiment is so precise that they will hardly be surpassed. That is, the restrictions they impose may endure as the most precise for decades. “For at least a decade, maybe two, we don’t see any improvement with a space satellite experiment,” says Manuel Rodriguesa scientist at the French aerospace laboratory ONERA and a member of the MICROSCOPE team.
The research has been published in the journal Physical Review Letters and in a special issue of Classical Quantum Gravity on September 14.
Share science, share knowledge.
