How to get out of the impasse in physics?
The next generation particle collider will cost billions of dollars. There are plans to build such devices in Europe and China, but scientists question whether this makes sense. Maybe we should look for a new way of experimenting and research that will lead to a breakthrough in physics?
The Standard Model has been repeatedly confirmed, including at the Large Hadron Collider (LHC), but it does not meet all the expectations of physics. It cannot explain mysteries such as the existence of dark matter and dark energy, or why gravity is so different from other fundamental forces.
In science traditionally dealing with such problems, there is a way to confirm or refute these hypotheses. collection of additional data - in this case, from better telescopes and microscopes, and maybe from a completely new, even larger super bumper that will create a chance to be discovered supersymmetric particles.
In 2012, the Institute of High Energy Physics of the Chinese Academy of Sciences announced a plan to build a giant super counter. Planned Electron Positron Collider (CEPC) it would have a circumference of about 100 km, almost four times that of the LHC (1). In response, in 2013, the operator of the LHC, i.e. CERN, announced its plan for a new collision device called Future Circular Collider (FCC).
1. Size comparison of the planned CEPC, FCC and LHC accelerators.
However, scientists and engineers are wondering if these projects will be worth the huge investment. Chen-Ning Yang, a Nobel Prize winner in particle physics, criticized the search for traces of supersymmetry using new supersymmetry three years ago on his blog, calling it a "guessing game." A very expensive guess. He was echoed by many scientists in China, and in Europe, the luminaries of science spoke in the same spirit about the FCC project.
This was reported to Gizmodo by Sabine Hossenfelder, a physicist at the Institute for Advanced Study in Frankfurt. -
Critics of projects to create more powerful colliders note that the situation is different from when it was built. It was known at the time that we were even looking for Bogs Higgs. Now the goals are less defined. And the silence in the results of experiments conducted by the Large Hadron Collider upgraded to accommodate the Higgs discovery — with no breakthrough findings since 2012 — is somewhat ominous.
In addition, there is a well-known, but perhaps not universal, fact that everything we know about the results of experiments at the LHC comes from the analysis of only about 0,003% of the data obtained then. We just couldn't handle more. It cannot be ruled out that the answers to the great questions of physics that haunt us are already in the 99,997% that we have not considered. So maybe you need not so much to build another big and expensive machine, but to find a way to analyze much more information?
It's worth considering, especially since physicists hope to squeeze even more out of the car. A two-year downtime (so-called) that began recently will keep the collider inactive until 2021, allowing for maintenance (2). It will then start operating at similar or somewhat higher energies, before undergoing a major upgrade in 2023, with completion scheduled for 2026.
This upgrade will cost one billion dollars (cheap compared to the planned cost of the FCC), and its goal is to create a so-called. High Luminosity-LHC. By 2030, this could increase tenfold the number of collisions a car produces per second.
2. Repair work on the LHC
it was a neutrino
One of the particles that was not detected at the LHC, although it was expected to be, is Wimp (-weakly interacting massive particles). These are hypothetical heavy particles (from 10 GeV / s² to several TeV / s², while the proton mass is slightly less than 1 GeV / s²) interacting with visible matter with a force comparable to the weak interaction. They would explain a mysterious mass called dark matter, which is five times more common in the universe than ordinary matter.
At the LHC, no WIMPs were found in these 0,003% of the experimental data. However, there are cheaper methods for this - for example. XENON-NT experiment (3), a huge vat of liquid xenon deep underground in Italy and in the process of being fed into the research network. In another huge vat of xenon, LZ in South Dakota, the search will begin as early as 2020.
Another experiment, consisting of supersensitive ultracold semiconductor detectors, is called SuperKDMS SNOLAB, will begin uploading data to Ontario in early 2020. So the chances of finally “shooting” these mysterious particles in the 20s of the XNUMXth century are increasing.
Wimps aren't the only dark matter candidates scientists are after. Instead, experiments can produce alternative particles called axions, which cannot be directly observed like neutrinos.
It is very likely that the next decade will belong to discoveries related to neutrinos. They are among the most abundant particles in the universe. At the same time, one of the most difficult to study, because neutrinos interact very weakly with ordinary matter.
Scientists have long known that this particle is made up of three separate so-called flavors and three separate mass states - but they don't exactly match flavors, and each flavor is a combination of three mass states due to quantum mechanics. The researchers hope to find out the exact meanings of these masses and the order in which they appear when they are combined to create each fragrance. Experiments such as KATHERINE in Germany, they must collect the data necessary to determine these values in the coming years.
3. XENON-nT detector model
Neutrinos have strange properties. Traveling in space, for example, they seem to oscillate between tastes. Experts from Jiangmen Underground Neutrino Observatory in China, which is expected to start collecting data on neutrinos emitted from nearby nuclear power plants next year.
There is a project of this type Super-Kamiokande, observations in Japan have been going on for a long time. The US has begun building its own neutrino test sites. LBNF in Illinois and an experiment with neutrinos at depth DUNE in South Dakota.
The $1,5 billion multi-country funded LBNF/DUNE project is expected to start in 2024 and be fully operational by 2027. Other experiments designed to unlock the secrets of the neutrino include AVENUE, at the Oak Ridge National Laboratory in Tennessee, and short baseline neutrino program, in Fermilab, Illinois.
In turn, in the project Legend-200, Scheduled to open in 2021, a phenomenon known as neutrinoless double beta decay will be studied. It is assumed that two neutrons from the nucleus of an atom simultaneously decay into protons, each of which ejects an electron and , comes into contact with another neutrino and annihilates.
If such a reaction existed, it would provide evidence that neutrinos are their own antimatter, indirectly confirming another theory about the early universe - explaining why there is more matter than antimatter.
Physicists also want to finally study the mysterious dark energy that penetrates space and leads to the expansion of the universe. Dark energy spectroscopy The tool (DESI) only started working last year and is expected to be launched in 2020. Large Synoptic Survey Telescope in Chile, piloted by the National Science Foundation/Department of Energy, a full-fledged research program using this equipment should begin in 2022.
On the other side (4), which was destined to become the event of the outgoing decade, will eventually become the hero of the twentieth anniversary. In addition to the planned searches, it will contribute to the study of dark energy by observing galaxies and their phenomena.
4. Visualization of the James Webb Telescope
What are we going to ask
In common sense, the next decade in physics will not be successful if ten years from now we are asking the same unanswered questions. It will be much better when we get the answers we want, but also when completely new questions arise, because we can't count on a situation in which physics will say, "I have no more questions," ever.
