Although our accurate knowledge of the composition of this universe and its origins represents the pinnacle of our achievements as human beings, it only explains 5% of the composition of the universe, and does not explain the four most famous cosmic forces that we know, which is gravity. Scientists think that there is something wrong with the mathematical models that they have built over decades, so they are trying to flip all possible papers so that any signal appears here or there, and in the meantime they are exploring the properties of some numbers that we would never have imagined the size of their impact on the whole universe , This substance is about one of them, which is a pure pure number that forms the universe with an amazing degree of accuracy!
On the other hand, we find that what we know as the “fine-structure constant” has no dimensions or units, but is a pure, pure number that forms the universe with an amazing degree of accuracy, described by the famous physicist Richard Feynman, saying: “It is a magic number that we got him without understanding.” As for Paul Dirac – one of the giants of quantum mechanics – he said that the origin of this number is “the fundamental problem that has not yet been solved in physics!”.
The fine-structure constant, denoted by the Greek letter α (alpha), is a number very close to the fraction 1/137, and it appears clearly in the mathematical formulas governing light and matter. Eric Cornell, a Nobel Prize-winning physicist at the University of Colorado, says: “In architecture, for example, the Golden Ratio appears clearly, as well as in the physics of low-energy materials, which includes the processes of atoms and molecules and then chemistry and biology, there is always a proportion of sizes From largest to smallest, these ratios tend to be multiples of the fine-structure constant.
This constant comes from everywhere. It describes the electromagnetic force, which affects charged particles like electrons and protons (they’re everywhere, the chair you’re sitting in, the phone you’re holding, your body itself, the solar system and all galaxies). “Everything that surrounds us in our everyday world is either subject to gravity or electromagnetic force, which is why alpha, or the fine-structure constant, is important,” said physicist Holger Muller at the University of California, Berkeley.
Because the ratio of 1/137 is a small value, the effect of the electromagnetic force is weak, and as a result, charged particles form atoms with most of their empty spaces, and their electrons revolve in orbits far from the nucleus, so it is easy to separate from the atom, which leads to the formation of chemical bonds (what bonds Basic chemical except the exchange of electrons between atoms).
On the other hand, we find that the constant is also large enough to cause an argument among physicists about the ratio if it were closer to 1/138, then stars would not be able to synthesize carbon, and life would not form in the form we are familiar with.
Although physicists have somewhat abandoned a century-old obsession about the source of the exact integer value of alpha (because of the difficulty), as well as now acknowledging that the value of the fundamental constants can be random and determined by the initial rolls of the dice at the birth of the universe, a new target loomed on the horizon.
Physicists want to measure the fine-structure constant as accurately as possible, it is everywhere, so accurate measurement of it allows physicists to test their theory about the interrelationships between elementary particles (the particles that make up the matter of the universe that we know in full), we are talking here about a group of The majestic equations known as the Standard Model of particle physics.
On the other hand, if there is any difference between the measured values of the relationship of particles with each other, it could indicate new particles that we do not know anything about yet, or perhaps effects that the standard equations do not take into account or just do not care about them. Cornell identifies these types of precise measurements as a third method for the experimental discovery of the fundamental principles of the universe, along with instruments such as particle colliders and telescopes.
In a research paper recently published by the journal Nature, a team of four physicists led by Saida Gelati-Khalifa at the Castler Brussel Laboratory in Paris announced the most accurate measurement to date of the fine-structure constant. And I found that the value of the constant appears in 11 digits, as the alpha value of α = 1/137.0359999206 (the last two digits – zero and six – are uncertain).
With an error of just 81 parts per trillion, the new measurement is almost three times more accurate than the previous best measurement of 2018 by the Mueller Group at Berkeley University, the team’s main competitor (the most accurate measurement was performed by Khalifa Gelati before the Mueller measurement in 2011). ). On his rival’s new alpha scale, Muller commented, “Its three times the accuracy, which is huge, so there is no need to be ashamed of calling it an excellent achievement of course.”
Gelati Khalifa has refined her experiment over the past 22 years, measuring the fine-structure constant by examining the rebound force of rubidium atoms as they absorb a photon (Muller does the same for cesium atoms). This rebound velocity expresses the weight of the atom, which is the most difficult factor to measure in order to arrive at a value for the fine-structure constant. “The bottleneck is always the least accurate (the most difficult) value,” Muller explained. “Any improvement in its measurement leads to an improvement in the fine-structure constant.”
This team of researchers, in Paris, began by cooling rubidium atoms almost to absolute zero, then threw them into a vacuum chamber. With a photon (Superposition is a phenomenon in the quantum world that means an atom can exist in several states at the same time).
Two copies of each atom are then fired in separate paths, then more laser pulses are used to push them together. In this case, the more the atom bounces back when it hits a photon, the more it is different in phase from the version it just met but didn’t hit.
The researchers measured this difference to calculate the rebound velocity of the atoms. “We infer from the rebound velocity the mass of the atom, which in turn is used to achieve a direct measurement of the fine-structure constant,” said Gelati Khalifa.
In such precise experiments, every detail is important, and one of the tables in the team’s research paper shows the so-called “error budget,” which are 16 sources of error and inaccuracy that can affect the final measurement, including gravity and Coriolis forces caused by the Earth’s rotation. Both have been carefully measured and considered, but a large part of the error budget is concerned with laser defects, so scientists have spent many years constantly improving them.
The hardest thing for Gelati Khalifa and her team was figuring out when to stop measuring and publish her research paper. It was on February 17, 2020, at a time when the Corona virus was spreading in France. Asked whether the decision to publish was an artist’s decision about when he saw the painting completed, Gilati replied: “Exactly, it’s like the artist’s decision about the completion of his painting, that’s exactly what happened.”
Surprisingly, Gelati’s new measurement differs from Mueller’s 2018 result in the tenth figure, and this represents a greater discrepancy than the allowable error value in both measurements, which means – with the exception of some fundamental differences between rubidium and cesium – that one or both measurements have an uncalculated error. Because measuring the Paris group is the most accurate, it is a priority at the moment, but both groups will improve their preparation and try again.
Although the two measurements differ, they closely match the alpha value inferred from precise measurements of an electron’s “g-factor,” a constant related to its magnetic moment, or the torque an electron experiences in a magnetic field.
“With a lot of math, you can correlate the fine-structure constant with the ‘g-factor’,” Cornell said. “If you miss some physical effects from the equations (of the Standard Model), we’ll get the wrong answer.”
Instead, we find that all the measurements are in perfect agreement, which largely rules out some assumptions about the existence of new particles. In 2018, scientists at this scale hailed the agreement between the best g-factor and Muller measurements as the Standard Model’s greatest triumph. “It’s the best fit between theory and experiment,” Gelati Khalifa commented about her new result’s better matching of expectations.
However, Gelati Khalifa and Muller set out to make further improvements. The Berkeley team has adopted a new laser with a better beam (allowing them to strike evenly a cloud of cesium atoms), while the Paris team plans to replace the vacuum chamber, among other improvements.
In response to the question of what kind of person would put so much effort in exchange for such meager improvements, Gelati Khalifa explained three traits: “You have to be meticulous, enthusiastic, and honest with yourself.” In response to the same question, Mueller replied: “I think it’s a lot of fun, because I love building shiny, beautiful equipment, and applying it to important things.”
Muller also noted that – of course – no one can build a high-energy collider on their own, such as the Large Hadron Collider in Europe (which is the world’s largest, highest-energy and fast particle accelerator). , related to fundamental physics, can occur provided he cooperates with only three or four other people.