Tag: higgs boson

  • Famous Scientists Whose Breakthroughs Never Won a Nobel Prize

    Famous Scientists Whose Breakthroughs Never Won a Nobel Prize

    In science, the Nobel Prizes are the ultimate distinction, yet not every great mind has been recognized. Dmitri Mendeleev, Ludwig Boltzmann, Edwin Hubble, Lise Meitner, and Stephen Hawking are just a few of the notable scientists who never won a Nobel Prize. But why haven’t we given a Nobel Prize to every excellent scientist? What were the excuses for them? Let’s take a look at the famous whose breakthroughs never won a Nobel Prize.

    Alfred Nobel, the creator of dynamite, established the Nobel Prizes in 1901 to recognize exceptional scientific contributions in the fields of physics, chemistry, and medicine. He was preoccupied with publicizing and fostering a widespread appreciation for significant human accomplishments. Numerous well-known scientists, whose work has had a lasting impact on our understanding of the world, earned a place on the extensive list of Nobel Prize winners.

    But the absence of some of science’s most illustrious figures is all the more glaring for it. From the master of black holes to the discoverer of Archaea to the inventor of the Big Bang, there are many famous people who have contributed to our understanding of the universe. However, it is puzzling that these scientific pioneers have been overlooked for the Nobel Prize.

    Between the suggestion and the awarding of the Nobel

    a look at the Nobel Prize procedure to understand the Famous scientists who never won a Nobel Prize
    From nominations to the ceremony, a look at the Nobel Prize procedure. (Image: N. Elmehed/NobelPrize.org)

    The circumstances surrounding a nomination and the actual awarding of the Nobel Prize are both crucial in determining whether or not that nominee will be honored. Despite the excellence of certain individuals, they have been denied receiving the Nobel Prize due to the strict requirements set out in Alfred Nobel’s will and also in the rules of the Nobel Foundation.

    For a Nobel to be awarded, the method requires the nominee to be put forth by other people. A year or more in advance, the Nobel Committee sends out anonymous nomination forms to specific scientists and academic institutions. Based on these recommendations, the committee makes its nominations in February. Only the prize winners’ identities are revealed; the nominees are kept hidden for 50 years.

    The Nobel Committee members are then advised by experts who have reviewed the work of the applicants. Over the course of the next several months, the committee of six members conducts many rounds of selection before casting their final decision at the beginning of October. Each of the six members of this committee is a specialist in either chemistry, physics, or medicine/physiology for the three distinct prizes, and all the members are chosen by the Swedish Academy of Sciences to serve staggered three-year terms.

    When the Nobel Prizes were initially established in 1901, the selection committees adhered more strictly to the terms of Alfred Nobel’s will than they do now. Many prominent researchers missed out on a Nobel Prize because of this.

    Mendeleev and the periodic table

    Dmitri Mendeleev
    Dmitri Mendeleev.

    Dmitri Mendeleev, who developed the periodic table, was one of these scientists who was never awarded a Nobel. In the middle of the 19th century, he and the German scientist Lothar Meyer independently constructed systems to account for the seemingly irrational “relationships” between some chemical components. In contrast to Meyer, Mendeleev understood that the resultant table was incomplete; it seemed that several elements had yet to be identified.

    When Dmitri Mendeleev presented his periodic table in 1869, he was initially met with skepticism and ignorance. However, several elements were found during the subsequent 15 years that filled in the blanks in Mendeleev’s table. Since then, chemistry has always relied on the periodic table of elements, and today, the colorful atomic table may be seen hanging in almost every school.

    But for no real reason at all, the Russian scientist was never awarded the Nobel Prize. Alfred Nobel specified in his will that the annual prize be given to the person or people who had done the most that year to improve human life. In the first years of the Nobel Prize, only recently active scientists were selected. Unfortunately, Mendeleev did not make the cut in this aspect.

    It’s true that a few committee members challenged the antiquity of his periodic table’s underlying findings. However, they failed to secure a majority. The man credited as the inventor of the periodic table passed away in obscurity in 1907. The norm now is to honor scientists even after decades of their discovery. Therefore, the criteria of “timeliness” are virtually irrelevant to the Nobel Prizes of today.

    This is the reason why a lot of early researchers didn’t win a Nobel Prize. They made ground-breaking findings, yet their colleagues and contemporaries didn’t believe them at first. They often had to wait decades for the validity of their breakthrough to be acknowledged. This is what happened to numerous scientists who were worthy of the Nobel Prize, including Alfred Wegener with his plate tectonics theory.

    Oswald Avery and his breakthrough in DNA

    Oswald Avery's research established DNA as the material carrier of genetic information.
    Oswald Avery’s research established DNA as the material carrier of genetic information.

    A striking example is a Canadian physician, Oswald Avery, who discovered that the DNA molecule stores our genetic information. Medical professionals and biochemists alike had a firm belief in the central role of proteins in cells as the primary agents of inheritance until the 1950s. Through his tests on pneumococci, Oswald Avery found that a threadlike white material seemed to be essential for genetic inheritance.

    Examination at a higher resolution revealed that the substance in question was not a protein but rather a deoxyribonucleic acid (DNA). Based on his research, Avery concluded that this molecule must serve as a vector for transmitting genetic information. In 1944, he released his results to the public, although they were poorly received at first. Protein theorists balked at the idea that the genetic code could be stored in DNA, which has only four different bases. Many still believed that the proteins were still present in the DNA, but this was not the case.

    Despite being nominated for the Nobel Prize 38 times, Oswald Avers was never awarded the prestigious prize. When it was finally realized in the 1950s that Avery was correct in his assessment of DNA as a hereditary molecule, it was too late for the doctor: Avery passed away in 1955, missing out on both the Nobel Prize and the celebration of James Watson and Francis Crick’s deciphering of the DNA code.

    Georges Lemaitre and the Big Bang

    Georges Lemaitre
    Georges Lemaitre was a Catholic priest and a physicist.

    Georges Lemaitre, the “Father” of the Big Bang, was another scientist who was centuries ahead of his time. In 1927, a Belgian priest and scientist realized the implications of the expanding universe. If one could rewind time, one would find that the whole cosmos was once concentrated in a single spot, a kind of “primordial nucleus” of the universe.

    However, when Lemaitre presented this theory to his fellow physicists, he was greeted with intense opposition. For the simple reason that conventional wisdom at the time held that the cosmos was static for all of eternity. Even to Albert Einstein, the notion that the universe may have emerged from some kind of “big bang” seemed practically inconceivable. When the Big Bang’s afterglow, known as “cosmic background radiation,” was detected in 1964, it provided further confirmation of Lemaitre’s Big Bang theory. Unfortunately, he passed away in 1966, so he never had the chance to accept the honor, if there was one.

    For Robert Brout, the discovery of the Higgs boson came too late

    Robert Brout
    File:Robert Brout.jpg” by Pnicolet, CC BY-SA 3.0.

    It is hardly surprising that theorists, a subset of scientists, have been mostly overlooked for the Nobel Prize. In most cases, it wasn’t enough that their discoveries were ground-breaking and crucial. No one has ever won a Nobel Prize for a theory, including the theory of relativity by Albert Einstein. Instead, in 1921, Einstein won the Nobel Prize for his work describing the photoelectric effect, which is the result of light’s interaction with matter.

    The Nobel Prize Committee’s preference for experimental breakthroughs may have a role in this; such feats are more intuitive and straightforward to categorize in terms of their significance. Many theoretical predictions and models are not accepted as valid until they have been verified experimentally.

    The 2016 detection of gravitational waves by the LIGO and Virgo collaborations is the most recent illustration of this phenomenon. Although Albert Einstein had predicted these space-time shocks and their production processes a century earlier, the Nobel Prize wasn’t given out until they were actually observed.

    Like the Higgs boson, the topic of what gives basic particles their mass has been debated by scientists since at least the 1960s. Then in 1964, Peter Higgs, Robert Brout, and Francois Englert reached the same conclusion: there must be a previously undiscovered sort of field with which these particles interact and, in turn, gain their mass. If this “Higgs field” did really exist, then it must also have a corresponding particle.

    However, the Higgs boson was first thought of as a theoretical particle. In 2012, researchers at the CERN research facility finally managed to identify the particle in the LHC particle accelerator. With this discovery, the three scientists who found the Higgs mechanism were theoretically also deserving of a Nobel Prize. However, for Robert Brout, the proof came too late since he died in 2011. That’s why the 2013 Nobel Prize in Physics went to only two of his colleagues who are still alive.

    Hawking: Revolutionary, but without a Nobel Prize

    stephen hawking picture

    Also, Stephen Hawking, a theoretical physicist, was unfortunate to win the Nobel Prize. The late British scientist was widely regarded as a leading figure in the fields of cosmology and physics. We owe him crucial insights into the nature and behavior of black holes, as well as important theories on the quantum-physical foundation of the Big Bang and cosmic inflation.

    Hawking theorized that black holes release some kind of radiation. Quantum fluctuations continually produce pairs of virtual particles and antiparticles, which give birth to this Hawking Radiation. While they normally cancel out in space, when one of these particles is beyond the event horizon, the outer particle is illuminated. As per Hawking’s theory, even tiny black holes may eventually evaporate into nothing but radiation if exposed to enough of it.

    Even though Hawking’s work is now central to cosmological and astrophysical understanding, he, too, was not awarded the Nobel Prize in Physics. Recent studies have provided indirect proof of Hawking Radiation, although many of his theories still require astronomical or experimental support. Now that Hawking is dead, this possibility has disappeared since Nobel Prizes are not awarded if the person is dead.

    Some of the early pioneers of theoretical physics, like Arnold Sommerfeld, one of the inventors of quantum theory, and Satyendra Nath Bose, for whom bosons are named today, met a similar fate. Though Stephen Hawking was nominated for the Nobel Prize 74 times, he was never awarded one.

    Edwin Hubble and the Redshift

    Edwin Hubble who never won a Nobel Prize.
    Edwin Hubble

    Working in a different scientific field prevented several scientists from missing out on the Nobel Prize. It wasn’t until fairly recently that scientists from closely related fields began receiving the Nobel Prizes in physics, chemistry, and medicine alongside their more-traditional counterparts. This resulted in many frustrated astronomers, biologists, and overly mathematical physicists.

    The American astronomer Edwin Hubble serves as a prime example of someone who did not receive a Nobel Prize. The Andromeda nebula, which could be seen in the sky even before his discovery, turned out to be a neighboring galaxy, not part of our Milky Way. Then, in 1929, he determined that the redder the wavelength of light from distant cosmic objects, the further away they are. Therefore, faraway things move away from us at a greater rate than those closer to us. Distance and redshift have a linear relationship.

    Hubble’s discoveries led to the revelation that the universe is continually expanding, which in turn provided the foundation for innumerable key insights about the evolution of the cosmos. His results provide the basis for the Hubble constant, which measures the expansion rate of the universe and thus bears his name.

    These ground-breaking results would easily warrant a Nobel Prize today. During Hubble’s lifetime, however, the Nobel Prize in Physics committee had a very limited view of his discipline and did not consider astronomy for a Nobel. Even though Hubble’s contributions influenced the cosmic perspective and, by extension, physics, he was not even considered for the Nobel Prize for decades. He had been passed over for the honor until the last days of his life in 1953, when three scientists finally thought to nominate him.

    Carl Woese and the Tree of Life

    Carl Woese
    Carl Woese. (Don Hamerman, CC BY 3.0)

    The American molecular scientist Carl Woese is another “victim” of the limited scope of the Nobel Prize. He was the one who first noticed that there are really three major branches in the family tree of existence. The archaea are the third major group of organisms on Earth after bacteria and eukaryotes. These one-celled creatures were at first classified as a subset of bacteria due to their shared lack of a nucleus and superficial resemblance to bacteria.

    But Carl Woese found important genetic variations in ribosomes, an ancient component of all organisms. These protein-producing factories inside cells house RNA molecules that exhibit species-related variation. Carl Woese discovered Archaea in the 1970s by meticulously examining the ribosomal RNA of different bacteria and other species.

    Phylogenetic Tree of Life based on the rRNA analysis by Woese.
    Phylogenetic Tree of Life based on the rRNA analysis by Woese. (Credit: Maulucioni, CC BY-SA 3.0)

    Additionally, Woese noticed that rRNA reflected the whole development of life, not just microbial classification. The results of Woese’s study shook up the fields of microbiology and evolution. Molecular phylogeny is still grounded in the comparison of ribosomal RNA. Yet, Woese did not get a Nobel Prize, and he passed away in 2012. His discoveries were overlooked by the Nobel Committee since they could not be classified within the fields of medicine, biomedicine, or chemistry.

    Lise Meitner and the discovery of nuclear fission

    Women researchers are another underrepresented group that has been overlooked for Nobel Prizes despite their merit. In the early years of the Nobel Prize, there were very few women in science, and those that did exist typically had to settle for working alongside their male counterparts. Many of them were not even considered for faculty positions or other academic leadership roles.

    Lise Meitner and Otto Hahn in 1913.
    Lise Meitner and Otto Hahn in 1913.

    Lise Meitner is one of the most infamous women who was denied a Nobel Prize. She was the first to detect the mechanisms underlying the nuclear fission of atoms, which presented crucial wisdom to her colleague Otto Hahn; she was born in 1878 and studied under Ludwig Boltzmann. As the first female physics professor in Berlin, Germany, Lise Meitner made history in 1926. However, her career was cut short in 1933 when, due to her Jewish heritage, she was fired and forced to depart the country.

    She worked and kept in touch with Hahn even while living in exile in Sweden. After doing an experiment with uranium in December 1938, he excitedly reported to her that no heavier nuclei but smaller ones had been produced by the experiment. Hahn remarked, “Perhaps you can come up with some sort of fantastic explanation. We knew ourselves that [uranium] can’t actually burst apart into [barium].”

    Then, Meitner and her nephew Otto Frisch set out to find a theoretical explanation, which they did. They concluded that the uranium atom had been split by a barrage of neutrons.

    Thus, both the possibility and the mechanism of nuclear fission became evident. In 1944, Otto Hahn received the Nobel Prize in Chemistry for his role in discovering nuclear fission and providing radiochemical confirmation of its existence. However, neither Lise Meitner nor Otto Frisch received a Nobel. The reason for this was obvious: Lise Meitner had a poor hand with the Nobel Prize Committee since she was a woman and also a Jew who was expelled from Germany.

    Rosalind Franklin and the structure of DNA

    Rosalind Franklin
    Rosalind Franklin in Paris. (Credit: CSHL, CC BY)

    One of Lise Meitner’s colleagues, the British biophysicist Rosalind Franklin, had a very similar incident when it came to not receiving a Nobel Prize. There is a good chance that James Watson and Francis Crick would not have successfully rebuilt the double helix structure of the hereditary molecule DNA without Rosalind. Because at the time, they and many of their peers believed DNA had to consist of three strands. Watson and Crick finally grasped what to look for only after obtaining Franklin’s X-ray DNA crystallography.

    The two scientists gained international renown in 1953 for their model of DNA’s double helix structure in the journal Nature. While Rosalind Franklin and her coworker Maurice Wilkins also submitted their data in the same journal issue, the model developed by Watson and Crick stood out the most. The discovery of DNA’s structure earned Crick, Watson, and Wilkins the Nobel Prize in 1962. Rosalind Franklin, whose contributions were crucial to this groundbreaking finding, was unfortunately ignored.

    Jocelyn Bell and the pulsars

    Dame Jocelyn Bell-Burnell

    There are instances of underappreciated female scientists in the field of astronomy, as well. There is Jocelyn Bell Burnell, the British radio astronomer who found the first pulsar. She was analyzing data from a brand-new radio telescope as part of her dissertation research at the University of Cambridge for her doctorate. In August of 1967, she discovered unexplainable radio signals inside it that followed an extremely regular pattern.

    Anthony Hewish, Bell Burnell’s dissertation advisor, first doubted that the signals had a natural origin because of their regularity. He humorously gave them the designation LGM-1, which stands for “Little Green Men.” However, Burnell discovered more pulsing radio signals that, like the stars, traveled across the sky. Bell Burnell eventually identified pulsars, which turned out to be the radio emissions from fast-spinning neutron stars.

    Her results were published in 1968 along with those of Hewish. The Nobel Prize in Physics was awarded to Anthony Hewish in 1974, and Jocelyn Bell Burnell was not included.


    Bibliography

    1. Featured Image: Photo by CEphoto, Uwe Aranas, CC BY 3.0, enhanced from original.
    2. “All Nobel Prizes”NobelPrize.org.
    3. “Nobel prize winners”. University of Cambridge. 2013.
    4. Alfred Nobel’s will – The establishment of the Nobel Prize”.
  • The Higgs Boson: Everything About the God Particle

    The Higgs Boson: Everything About the God Particle

    Paul Dirac named these particles “bosons” to honor Satyendra Nath Bose, an Indian scientist who developed the idea with Albert Einstein. The discovery of the Higgs boson on July 4, 2012, marked a turning point in physics. With it, the fundamental component of the cosmos that gives everything its mass has been identified. But 10 years later, there are still many unresolved concerns regarding this special particle called the “god particle” and its impact on the foundations of our conception of the physical universe.

    Our planet would likely not exist at all if it weren’t for the Higgs field and the Higgs boson that goes along with it. Several physicists, including Robert Brout, Francois Englert, and Peter Higgs, proposed this as early as 1964. The expected particle has now been discovered as of 2012. However, the Standard Model of particle physics still has a few significant holes. Additionally, the Higgs boson has in some ways generated more questions than it has resolved. So, what’s the next step?

    What Makes the Higgs Boson Special?

    The absence of mass would result in a cosmos devoid of atoms and other forms of ordinary matter. The fundamental constituents of matter stick together and interact with one another only because of the mass of the particles that make them up. But from whence does the mass of the constituent particles come? For a very long time, the Standard Model of particle physics—the foundation of our conception of the physical universe—did not provide a solution.

    The Weak Nuclear Force

    Additionally, there is a difficulty with the bosons, which serve as the basic forces’ carriers. According to theory, they should not have any mass, unlike fermions that create matter, such as quarks and electrons. Photons and gluons are also examples of carrier particles of electromagnetic and strong nuclear forces. They have no mass. Photons may thus travel at the speed of light without encountering any obstacles.

    The weak nuclear force, however, does not work with the plan: On the one hand, it contains two carrier particles, the W and Z bosons, instead of one. And these bosons, on the other hand, have a mass. This explains the weak nuclear force’s limited range and how it works in radioactive decay. However, for many years, it was unknown how and why only these exchange particles, but not the others, acquire mass.

    The Scalar Field

    Could particles have mass due to a field that permeates the whole universe? (Image: CERN)
    Could particles have mass due to a field that permeates the whole universe? (Image: CERN)

    Further light was shed on the issue only in the early 1960s, when numerous theoretical physicists, including Peter Higgs in Great Britain and Robert Brout and Francois Englert in Belgium, started looking for a solution. They independently concluded that the issue may be resolved by an unseen field that permeates the whole cosmos. Some of the constituent particles may interact with this scalar field in quantum interactions, modifying their characteristics. So, they can only move by using energy, and because of this, they have mass.

    The Brout-Englert-Higgs mechanism is often compared to a cocktail party by the British physicist David Miller. A throng of other guests swiftly congregates around a significant celebrity as soon as it enters the room. Due to the crowd, the celebrity is unable to travel very far—much like a particle with a large mass that can only be propelled with a lot of energy.

    Asymmetrical Effect

    The Brout-Englert-Higgs mechanism also explains the fact that not all carrier particles have mass: The Higgs field has an asymmetry; it does not interact with all bosons uniformly. The carrier particles of these forces, photons, and gluons, remain massless since they are neutral regard to electrodynamics and quantum chromodynamics. However, the field has a kind of braking effect on all other particles and gives them mass.

    This is comparable to how fur has its hair growing in one direction: a particle, like a photon, feels no resistance and maintains its masslessness if it flows along the Higgs field’s “hairline.” On the other hand, when a particle goes against the flow, more energy is needed, and the particle accumulates mass. This holds for all fermions that may form matter, as well as for the W and Z bosons of the weak nuclear force.

    The Higgs Field

    That makes up the theory. But how can you back it up? The Higgs boson enters the picture here. Because if such a scalar field exists, it is capable of condensing at certain locations. The Higgs field may also appear as a particle at these locations, just as a photon is both a wave and a particle. “What else can be keeping the agreement between the Standard Model and the data just as good as it is? If there is not a Higgs boson, the theory does not make sense at all.” Peter Higgs said in 2004.

    Even then, the physicist was sure that this missing component of the Standard Model’s puzzle would soon be discovered. The Higgs boson was sought after.

    How Was the Higgs Boson Discovered?

    One of the LHC's all-purpose detectors is the ATLAS detector. The Higgs boson was discovered for the first time by ATLAS and the CMS detector.
    One of the LHC’s all-purpose detectors is the ATLAS detector. The Higgs boson was discovered for the first time by ATLAS and the CMS detector.

    The Higgs boson was ultimately discovered in 2012 after almost 50 years of worldwide investigation by scientists. But why was it so challenging to find this missing Standard Model particle?

    The issue was that the theory did not predict the characteristic that was essential for the experimental finding of the Higgs boson. These theories predict that this particle should just have mass and not spin or charge. But it was unknown how big this mass was. Only 18 megaelectronvolts to 800 gigaelectronvolts were within the range that could be used. The energy required to accelerate a particle is indicated in electron volts. This also applies to an elementary particle’s mass.

    This has the following implications for the search for a particle: If you know the mass, you also know the energies at which you must fire particles at each other to generate the particle you are seeking in a collision. But when it came to the Higgs boson, researchers were stumbling about in the dark, and, on top of that, particle accelerators could only produce collision energy up to a certain point. Since these tests had previously shown that the Higgs boson would likely need to be heavier than 114 gigaelectronvolts, this was not entirely surprising.

    Locating a Needle in a Haystack

    The quest for the Higgs boson received a significant boost in 2008 with the start of operation of the Large Hadron Collider (LHC) at the CERN research facility close to Geneva. Because the finest circumstances for eventually discovering the sought-after particle were provided by this biggest particle accelerator in the world’s high-energy proton collisions. If the universe took the shape of the Higgs mechanism predicted by the Standard Model, there was no way to hide once the LHC got going.

    The Higgs boson, however, decays back into the matter in less than a trillionth of a second and is only produced in around one out of a billion proton collisions. As a result, it cannot be directly viewed or quantified. Only the decay products it leaves behind may be used to identify it. Sadly, they are made of elementary particles like pairs of photons, muons, or Z-bosons, which are also released when the other collision products break down.

    Therefore, finding the Higgs boson’s signature among all of these millions of particles is more like seeking out a specific haystack than it is like hunting for the fabled needle. The seemingly impossible procedure was made feasible by carefully analyzing which decay products, based on known mechanisms, the detectors should find, and then examining if there are deviations from this anticipated curve in a mass and energy range. If the Higgs boson was involved, there would be a little extra of the things that happen when it breaks down.

    Unevenness in the Curve

    Simulation of a particle collision that results in the production of the Higgs boson. (Image: CMS/Lucas Taylor)
    Simulation of a particle collision that results in the production of the Higgs boson. (Image: CMS/Lucas Taylor)

    The same thing was seen at the LHC, at not only one but two of the big detectors: On July 4, 2012, representatives from the ATLAS and CMS consortia made their long-awaited announcement in front of the world’s media: the distinct signature of the Higgs boson has been found independently at both detectors. This could be found by looking for a “hump” in the decay product curve that is caused by the photon pairs or Z bosons that are made when the Higgs decays.

    More than five standard deviations of significance were attained for both outcomes, which equates to a likelihood of nearly 3.5 million to one that the results are not just coincidental. The data from ATLAS and CMS satisfied the criteria for the official discovery of a particle with this value. Their findings indicated that this particle likewise required a mass of around 125 gigaelectronvolts. This matched the exact mass range in which the Higgs boson was thought to be present based on past searches.

    Breakthrough in Physics

    The Higgs boson, the last piece of the Standard Model’s jigsaw, was discovered after decades of research. Its discovery proved both the existence of a cosmic scalar field that provides mass and the Brout-Englert-Higgs mechanism, which was proposed more than 50 years ago.

    For scientists throughout the globe, the discovery of the Higgs boson constituted a significant turning point. Peter Higgs and Francois Englert were awarded the 2013 Nobel Prize in Physics for their work. The hundreds of experimental physicists at CERN who participated in the search, and the theorists who had already passed away, were left empty-handed since the Nobel Prize may only be shared by a maximum of three live individuals.

    The Particles Next to the Higgs Boson

    The Standard Model of particle physics places a significant emphasis on the Higgs boson. (© CERN / Daniel Dominguez)
    The Standard Model of particle physics places a significant emphasis on the Higgs boson. (© CERN / Daniel Dominguez)

    The Higgs boson is the cornerstone of the Standard Model, so everything that is discovered about this particle is important to the basic rules of physics. One of the most important questions about the Higgs boson’s interactions after its discovery was: Does the Higgs couple with other particles in the manner predicted by theory? Its discovery involves interactions with photons, W bosons, and Z bosons in each of the decays that were investigated. But the Higgs would also need to interact specifically with quarks and leptons if it is the “mass-giver” particle we are seeking. The latter include the heavier “siblings” of the electron, the muon and tau lepton.

    The Higgs boson’s decay into bottom quarks and tau leptons allowed researchers at the LHC to discover the first of these interactions in 2016. This demonstrated that the Higgs truly interacts with matter particles as well as the fundamental force’s carrier particles. It took a little longer to find the Higgs boson’s most frequent decay: this preferred decay of the Higgs into two bottom quarks should occur 58 percent of the time.

    But amid the “haystack” of many particles created by proton collisions in the particle accelerator, it was impossible to identify this decay phase. The evidence was finally available in 2018, when the ATLAS detector and the CMS detector at the LHC both produced data that demonstrated the Higgs boson’s decay into two bottom quarks with a significance of more than five sigmas.

    A Strong Competition

    Particle traces of a ttH event, or the interaction of a top quark and the Higgs boson. (Image: CERN)
    Particle traces of a ttH event, or the interaction of a top quark and the Higgs boson. (Image: CERN)

    The Higgs boson should have the greatest coupling to the top quark, the particle that makes up the bulk of matter, according to the theory; only then does it get its huge mass. If true, certain proton collisions at the LHC should result in the production of a Higgs boson, together with a top quark and an anti-top quark.

    However, this so-called ttH production method is exceedingly uncommon; just 1 percent of the Higgs bosons are formed together with top quarks. The only way to identify top quarks is via the decay products they leave behind since they are not stable. As a result, it took until 2018 for the measurements at the LHC to be of sufficient relevance. This was the first time that this mechanism had been empirically proven. The scientists had now witnessed all of the Higgs boson’s interactions with third-generation heavy quarks and leptons, as well as all of the significant ways that the particle was produced.

    From the “Higgs Portal” to Dark Matter

    However, interactions between undiscovered elementary particles and those specified by the theory might be much more intriguing: The Higgs boson, unlike other particles in the Standard Model, has no charge nor spin and may therefore interact with neutral particles, including types of bosons that have not yet been identified. Many scientists believe that such a neutral particle might be the long-sought dark matter particle.

    We also refer to this potential as the Higgs portal. This makes the Higgs a terrific instrument for the quest for dark matter. Some Higgs decay products appear to be missing from some bosons in the LHC could be one way to find these “dark” interactions. When neutral “dark bosons” that cannot be identified by detectors are produced during the process, they either escape unnoticed or cause an imbalance in the known decay patterns.

    Physicists at CERN may have discovered some early proof of recognizable divergences thus far. But they have a long way to go before they can find them or pinpoint exactly what they are. During the third run of the LHC, which has started, they are hoping for better data and higher Higgs production.

    The Higgs Field’s Hidden Properties

    The sombero or champagne bottle model of the Higgs field. (Image credit: ©Gonis / 
    The sombero or champagne bottle model of the Higgs field. (Image credit: ©Gonis / 
    CC-by-SA 3.0)

    The Standard Model of Physics now has a substantial hole that the Higgs boson has filled. But even though it has been found, there are still many questions about it, not the least of which is what the Higgs field and its particles are made of. The Higgs boson is often presented as the particle that completes the Standard Model but in practice, it brings up a ton of new issues.

    Spontaneous Symmetry

    One of them addresses the history and characteristics of the Higgs field. The Higgs boson is the first and only scalar particle among the basic forces of existence. The Higgs field, in contrast to other forces, has no preferred direction and is consistent even when reflected. The theory states that this field was produced immediately after the Big Bang, long before atoms were ever thought of.

    Initially, the Higgs field’s scalar values averaged zero everywhere. Nothing and no one had mass as a consequence. The Higgs field, however, experienced a spontaneous symmetry breach only a few fractions of a second after the Big Bang, adopting a new configuration whose values, on average, amount to an energy of around 246 gigaelectronvolts. It started to affect other fields and particles, giving some of them mass. The counterintuitive aspect of this is that although the physical world is not symmetrical, the equations defining this field are nonetheless symmetrical.

    Physicists also use the sombrero (the Mexican hat) or champagne bottle models to explain this spontaneous symmetry breakdown of the Higgs field: The scalar field looks like the curving sombrero or champagne bottle’s upturned bottom. The field’s design allows for complete symmetry, such that everything would balance on the middle elevation if a pencil were placed there. However, in practice, the pencil topples over relatively rapidly and falls in one direction, breaking the symmetry—at least for the pencil—even while the field’s form remains unchanged.

    Beyond the Hat’s Brim

    The issue with this scenario is that it is not yet apparent if or how the Higgs field can be accurately characterized by the Sombrero model and how it continues once past the brim of the hat. Is it possible that there is a chasm beyond it where the field might take on even lower values than in the valley of the “hat brim”? The field would only be metastable at that point and may shift into a brand-new, lower energy state. The Higgs field would be stable if the values of the “hat brim” kept expanding outward.

    The so-called triple gauge boson couplings—a characteristic that represents the interaction of the Higgs boson with its own peers—is one method of providing an answer to this query. According to the theory, the Higgs particle may be the only one in the Standard Model to interact with itself. In the particle accelerator, some Higgs bosons would have to decay into two more Higgs bosons if this were the case.

    The frequency and energy at which this triple-coupling happens, if it does exist, will be crucial in determining whether the Higgs field behaves as predicted by the Standard Model or if there is an opportunity for “new physics” in the form of undiscovered particles or forces. Scientists aim to have more and better data in the third run of the LHC, which started on July 5th, 2022. The ATLAS team at the LHC has already started hunting for the decay products of such triple boson production.

    Divisibility of the Higgs

    And the ATLAS collaboration’s researchers are presently looking into yet another query about the Higgs boson: Does the Higgs boson even have a substructure or is it a true, indivisible fundamental particle like photons, quarks, and gluons? This is predicted by several theories of physical processes beyond the Standard Model. These models suggest that the Higgs could more closely resemble the pion, a particle made up of an up quark and an anti-down quark that mediates the bonding between protons and neutrons in the atomic nucleus.

    The production of unusual “vector-like” quarks would be a sign of such a substructure of the Higgs boson. The first analyses of the collision data from the LHC were presented by physicists with the ATLAS collaboration in 2021. But as of now, these findings show that the Higgs boson operates as predicted by the Standard Model, proving that it is a real elementary particle.

    But the study of the Higgs boson and its quirks has only just started. Because if we can detect the properties of the Higgs, then it will address some of the hottest concerns in physics.

    Future for the Lhc and the Higgs Boson

    Future Circular Collider (FCC) collisions with energies of up to 100 teraelectronvolts will be possible. (Image credit: CERN)
    Future Circular Collider (FCC) collisions with energies of up to 100 teraelectronvolts will be possible. (Image credit: CERN)

    The Higgs boson’s discovery was a significant achievement in physics. However, significant advances in particle physics have not been made since, and many important topics remain unresolved. It has taken a while for physicists to finally see the abundance of new particles and scientific advances they had hoped for, particularly from the second run of the LHC and the discovery of the Higgs boson. For now, the LHC has mostly discovered the Higgs boson and the Higgs field it carries. 

    But in reality, there are still a lot of issues that physics has to address. Because there are still significant gaps in the Standard Model, even with some ambiguities clarified by the Higgs boson. For instance, Albert Einstein attempted to provide a true explanation of how the fourth basic force, gravity, relates to the other fundamental forces, but he was unsuccessful. It is also unknown whether gravity contains a carrier particle similar to those found in the other fundamental forces.

    It is also unclear why, immediately after the Big Bang, the universe did not collapse once again. Because at that time, equal and oppositely huge amounts of matter and antimatter should have been created, and they would have destroyed one another. Yet, it is clear that the great annihilation did not occur since we would not be here now. Because of this, scientists believe that there must have been a small distinction between the properties or behaviors of particles and their antimatter counterparts. But thus far, searching for it has been fruitless.

    Dark Energy and Dark Matter

    Additionally, dark energy and dark matter—two components whose existence is still entirely unknown—constitute about 95 percent of our universe. The expansion of our universe is being driven by dark energy. Astronomers and physicists are still unsure of how it does this and why cosmic expansion is speeding up.

    Dark matter is almost as enigmatic but a bit more researched. According to what we know about it, it must exist practically everywhere in the universe, including our solar system and the halo of the Milky Way. The velocity and form of galaxy clusters and galaxies are influenced by their existence. However, dark matter’s nature is likewise unknown since gravity is essentially its only mode of interaction with regular matter. It is still unclear what kinds of particles dark matter is made of and if a boson like the Higgs may be responsible.

    Some basic issues concerning behavior and characteristics in the field of particle physics remain unanswered. One is the supersymmetry theory, which states that every known particle should have an additional, heavier, unnamed partner. However, there has been no sign of these hypothetical particles in the data as of yet. The proponents of this theory had anticipated a glut of such supersymmetry particles even from the initial runtimes of the LHC.

    Scientists are still debating whether neutrinos exist in a fourth, sterile form in the case of these “ghost particles.” There are still some unresolved contradictions in the electroweak interaction, which results from the coupling of the electromagnetic and weak basic forces. People look to the Higgs boson and how it decays for more information, especially in this area.

    All of these occurrences could be caused by “new physics”—processes and particles that have not yet been discovered. However, this has so far been well disguised from the physics community’s view. Certain obvious discrepancies have been found by physicists at the LHC and other particle accelerators, such as in the magnetic moment of the muon or B meson decays. The main issues, however, still have not been resolved.

    The third run of the LHC at CERN is now expected to provide at least some answers. Because it is significantly more potent, numerous collisions could at least confirm and aid in elucidating the oddities previously picked up in hints. The maximum 13.4 teraelectronvolts that the LHC can produce in proton collisions is insufficient to explain many of the phenomena that are currently unsolved. More energy and alternative techniques are needed.

    “Future Circular Collider” (FCC)

    Due to this, some follow-up initiatives using more potent and substantial particle accelerators are already being discussed. The “Physics Beyond Colliders” initiative at CERN is investigating the future of accelerator rings. A 100-kilometer acceleration ring is also being developed for the years after 2040. Electrons and positrons will first collide and operate as a “Higgs boson factory” in this “Future Circular Collider” (FCC). The Higgs products are simpler to study since they smash with less energy yet create fewer interfering particles.

    Later, the FCC will host proton collisions with energies of up to 100 teraelectronvolts. In the shape of an electron and positron ring accelerator of comparable scale to the CEPC, China is likewise preparing to build its version of the Higgs factory. A linear accelerator has been discussed in Japan, but it is unclear if the government will contribute to its funding. Some physicists are placing their hopes in novel kinds of mini particle accelerators that accelerate electrons with the use of plasma lasers in addition to the massive, pricey facilities. Their energies are often modest, but they are cheap, portable, and might be utilized to specifically examine certain sub-aspects.

    It is too soon to say which of these initiatives will be carried out and which will succeed. But it is evident that to find new physics outside of the Standard Model, we must use every tool at our disposal, including astrophysical data, modest experiments at lower energies, and massive high-energy particle accelerators.


    Bibliography

    1. Notes on Dirac’s lecture Developments in Atomic Theory, 1945
    2. The Bose in the Boson. The New York Times.
    3. Higgs boson: The poetry of subatomic particles. BBC News.