Open-ended questions in physics that scientists would most like to receive answers to. Fundamental mysteries of nature shrouded in mystery.
All physics as a science is about exploring the most fundamental mysteries of nature, and it is therefore not surprising that physicists are constantly thinking about several basic questions about the universe. Recently, Symmetry Magazine (published by two US government-funded physics laboratories) asked a group of nuclear physicists to name the open-ended physics questions they would most like to get answered. Here are examples of those mysteries in physics that have been named.
What is the fate of our universe?
As you know, the poet Robert Frost once asked if the world ended in fire or ice? And physicists still cannot answer this question. The future of the universe - this question has been named by Steve Wimpenny of the University of California, Riverside - is heavily dependent on dark energy, which is currently unknown.
Dark energy is responsible for accelerating the expansion of the universe, but the origin of this energy remains a mystery. If dark energy becomes constant over time, then, probably, in the future we will have a "big cold" - at this moment the universe will expand faster and faster, and eventually the galaxies will be so far apart that outer space will seem huge wasteland. If dark energy increases, then the expansion can become even more intense, and then not only the space between galaxies, but also the space inside them will expand, and then the galaxies themselves will scatter to shreds. This version of fate was called the "big gap".
Another possibility is that dark energy will decrease, and in this case, it will no longer be able to withstand the centripetal force of gravity, which will lead to the retreat of the universe inward during the "big crunch". That is, in fact, in any case, we are doomed.
On the bright side, none of these possible events will happen in the next billions or even trillions of years - enough time to decide which option to choose - fire or ice?
The Higgs boson makes absolutely no sense. Why does he exist then?
The tone of this question is derisive, says Richard Ruiz of the University of Pittsburgh, who asked him, but the question itself points to a very real misunderstanding of the nature of the particle, which was so remarkably discovered last year at the Large Hadron Collider (LHC) in Europe. … The Higgs boson helps explain how all the other particles got their mass, but it also raises a lot of other questions. Why, for example, the Higgs bosons interact differently with other particles: The up quark interacts more strongly with the Higgs boson than the electron, which gives the up quark more mass than the electron.
“This is just one example of non-universal forces at work in the Standard Model,” says Ruiz. Moreover, the Higgs boson is the first fundamental particle found in nature with zero rotation. “This is a completely new sector of the Standard Model of particle physics,” notes Rius. "However, we have no idea how this happens."
Why is the universe so perfectly balanced that life can exist?
In terms of probability, we really shouldn't have been here at all. Galaxies, stars, planets and humans are only possible in a universe that expanded at the required rate in its early period. This expansion was driven by the outward pressure of dark energy in conflict with the inward gravitational forces of the mass of a universe dominated by an invisible substance called dark matter. If the balance of forces between these elements were different, if, for example, there was only a little more dark energy after the birth of the universe, then space would expand too quickly for galaxies and stars to form. And if there was a drop of dark energy less, then this would lead to collapse within the universe itself.
But why, asks Eric Ramberg of Fermilab in Batavia, Illinois, were they so cleverly balanced that a universe was created that we can live in? “We don't know the fundamental reason,” he notes. "There is no doubt that the amount of dark energy in the universe is the most perfectly tuned system in the history of physics."
Where do astrophysical neutrinos come from?
Extremely energetic neutrinos are thought to be the result of collisions of fast charged particles called cosmic rays with light particles (photons) in the background of cosmic microwave radiation propagating through the universe. But what drives this process and how cosmic rays are accelerated are open questions. The leading theory is that matter falls into hungry supermassive black holes in the center of galaxies, and thus generates cosmic rays, but there is no evidence of this hypothesis yet. The resulting neutrinos are thought to travel at such a high speed that any tiny particle has the same amount of energy inside it as a baseball (which is made up of billions of billions of atoms) flying at high speed. "We can't even figure out where these particles come from," admits Abigeil Vieregg of the Kavli Institute for Cosmological Physics in the Kavli Institute for Cosmological Physics. "By finding out, we can learn about the sources of acceleration of these particles to extremely high energies."
How is it that the universe is made of matter and not antimatter?
Antimatter is like matter, only in it everything is the other way around, like on the Opposite Day. It has the same qualities as that of the substance of which planets, stars and galaxies are made, but one important element in it is another - charge. The universe is said to have originated with equal amounts of matter and antimatter, but somehow matter won out, and as a result, significant parts of both substances destroyed each other in the big bang, leaving only a small amount of matter. Why Antimatter lost the tug-of-war competition, nobody knows. To explain this disparity, scientists are looking for a process called charge parity violation, in which particles prefer to decompose to matter rather than to antimatter. “We are particularly interested in understanding whether the neutrino wobble is different from the antineutrino wobble," said Alysia Marino of the University of Colorado, who shared her views with Symmetry. "We haven't been able to see this yet, but we hope that the participants in the next generations of experiments will be able to understand this in more detail."
