"This is the first measurement ever made of the free fall of antimatter (antihydrogen) atoms that directly shows that they really fall down," explained Prof. Eli Sharid from the Physics Department at Ben-Gurion University of the Negev, the member of the ALPHA collaboration group
Isaac Newton's historic study of gravity was apparently inspired by watching an apple fall from a tree to Earth. But what about an "anti-apple" made of antimatter, does it fall the same way if it existed? An international group of scientists with the participation of Prof. Eli Sherid from the Physics Department at Ben-Gurion University of the Negev, the only Israeli partner in the research, performed the first ever measurement of free-falling antimatter atoms and compared their energy to ordinary matter atoms. The research findings constitute a milestone in the study of the properties and behavior of antimatter and were published in the prestigious journal Nature.
Albert Einstein's theory of relativity described the effects of gravity as early as 1915 and has been studied extensively since then. A central element of the theory called the 'principle of weak equivalence' states that all objects, regardless of their mass or composition, should fall freely in the same way in response to gravity. Although it is widely believed that antimatter should behave in the same way as matter in response to Earth's gravitational pull, direct observations of matter have been lacking, due to challenges in creating carefully controlled experimental conditions.
The international group of scientists 'Alpha' (ALPHA) was established in 2005 for the purposes of research of anti-hydrogen atoms, as a follow-up experiment to the 'ATHENA' experiment conducted at the CERN research center in Geneva, Switzerland. Antihydrogen atoms consist of an antiproton as a nucleus (the antiparticle of the proton found in a normal hydrogen atom) and a positron (the antiparticle of the electron). Since anti-hydrogen atoms have no electric charge, they are difficult to trap. Any contact with normal material such as the walls of the trap causes their destruction (annihilation). The Alpha research group was the first to develop magnetic techniques for trapping cold anti-hydrogen atoms (2012), and the first to perform measurements of their energy levels (2017-2019). Now she is also the first to measure the free fall of these antiatoms.
Gravitational force is the force of attraction between any two objects that have mass. It is the weakest of the four basic forces of nature (strong nuclear force, electro-magnetic force, weak nuclear force and gravity). Antihydrogen atoms are neutral, electrically stable particles of antimatter. Electric neutrality greatly facilitates the possibility of directly measuring the gravitational behavior of antimatter without the effects of electric fields competing with the measured motion.
The traps built by Alpha until 2018 were horizontal traps, in which the cooling and trapping techniques of the anti-hydrogen atoms were developed. In a trap called ALPHA-2, laser radiation or microwaves reacted with the anti-hydrogen atoms to measure their internal structure. This time, a new and vertical trap called ALPHA-g was built, especially to enable accurate measurement of the free fall of the anti-atoms. The principle of the measurement is the capture of the cold anti-atoms, which move up and down inside the trap, then releasing them by lowering the magnetic fields that create the trap. Without these fields, the anti-atoms exit the trap and when they reach the material wall - are destroyed, an effect that can be measured. Computer simulations of the experiment indicated that if the anti-atoms fell like normal atoms, only about 20% of the atoms came out of the top of the trap and 80% from the bottom. By averaging the results of the experiments when the atoms were released, the scientists found that the results matched expectations from the simulations assuming a fall 'down' like normal atoms. The possibility that the anti-atoms fall 'up' was ruled out. The full study involved repeating the experiment several times for different values of an additional magnetic field, which can strengthen or counteract gravity. By analyzing the results from these experiments, it was found that to an accuracy of about 20% the acceleration of an anti-hydrogen atom corresponds to the well-known and attractive force of attraction between the material and the Earth-matter.
"This is the first measurement ever made of free-falling antimatter (anti-hydrogen) atoms that directly shows that they really fall down," he explained. Prof. Eli Sharid from the Department of Physics at Ben-Gurion University of the Negev. Sherid, a member of the international research group 'Alpha' since 2005 and the only Israeli member of it. "It's been 18 years since we were the first group to create and capture cold anti-hydrogen atoms in the particle accelerator, and the only one to measure atomic transitions in these atoms and compare their energy to 'normal' matter atoms. Now it's time for gravitation. The accuracy of the current measurement is only the beginning. Following this groundbreaking measurement, we hope to improve the measurement accuracy to about 1% already in the next year of experiments, 2024."
"It took us 30 years to learn how to make this anti-atom, hold it and control it well enough to be able to drop it in such a way that it would be sensitive to gravity," an Alpha spokesman said. Jeffrey Hangst. "The next step is to measure the acceleration as accurately as we can. We want to test whether matter and antimatter actually fall in the same way. Laser cooling of anti-hydrogen atoms is expected to have a significant effect on accuracy."
This research was supported by the National Science Foundation of Israel (Grant No. 1099/18) - ISF, and agencies from around the world - the Natural Science Foundation (NSF), the Ministry of Energy (DOE), the Engineering and Physical Sciences Research Council (EPSRC), the Facilities Council Science and Technology (STFC), VR (Sweden), Laborholm Foundation (UK), Royal Society, Carlsberg Foundation (Denmark), FNU Nice Center, DRAC Canada, CFI, EHPDS/EHDRS, NRC/TRIUMF, Natural Sciences and Engineering Research Council of Canada (NSERC) , ENAFAE Brazil, FAPERJ, CNPq.
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We are already in a period of new physics.
The idea of gravity was given to the world by Newton 330 years ago.
Newton thought that there was a mysterious and wonderful force emanating from the depths of the earth, and its whole function was to drop to the ground objects that were loosed from them.
Newton gave this mysterious force the name gravity.
Newton did not know that objects they let go of fall by themselves, thus fulfilling a wonderful law of nature, which is the law of conservation of energy. This law was accepted in science only 170 years ago, and Newton did not know about its existence.
To lift an actual body off the ground to a height of 1 meter, you have to make an effort, and get tired, and this amount of fatigue represents an amount of energy.
If we release this body, it will fall down by itself with increasing speed,
And the blow of his hitting the ground will show exactly - the same amount of energy that was needed to lift him to a height of 1 meter.
This is how physical reality works, and it is she who taught scientists about the existence of a wonderful physical law of nature - the law of conservation of energy.
There are many types of energy, and they can replace each other, according to the law of conservation of energy. Physical reality operates by itself freely, and it upholds a miraculous law of nature - the law of conservation of energy.
The law of conservation of energy completely eliminates Newton's idea of gravity, and it is time to leave Newton's physics, and move to another physics.
Newton's physics is about to be replaced by Esbar's physics. which appears in the book "The Magical Journey of Asbar on the Wings of Natural Knowledge"
A. Asbar
Ed
Where would you get anti-hydrogen?
I read and pondered among myself if it was possible in a similar way to control the process of meeting hydrogen and anti-hydrogen atoms, in terms of quantity and location. The result may be a controlled production of energy.
From a certain point on, the question in this type of project is a question of cost benefit, with the main variable likely to be the costs involved in running the cooling and trapping techniques of the anti-hydrogen atoms.