According to most physicists it really must be there: the Higgs boson. Unfortunately, it doesn't really want to cooperate to be discovered. What is the need for the Higgs boson and why do most physicists, despite the virtually absent experimental evidence, think it must exist?
Why is such a thing as the Higgs boson needed?
In the Standard Model of physics, all natural phenomena, excluding gravity, arise from three (or rather, two) forces: the strong nuclear force, the electromagnetic force, and the weak nuclear force. Both last forces appear to be manifestations of one force: the electroweak force. This model describes all known particles: quarks, leptons (such as electrons and neutrinos) and gauge bosons (photons, gluons, W and Z particles), quite nicely. Composite particles, such as the tri-quark protons and neutrons, can also be described well.
Where does mass come from?
There is one problem, however: mass. The equations of the Standard Model do not explain why, for example, the mass of the W boson is much larger than that of an electron or neutrino or why photons have no mass and quarks do. Or, why the masses of the particles are as large as they are.
(The Higgs Mechanism Explained, courtesy of Julie)
For that reason, the so-called Higgs mechanism has been introduced in the Standard Model. According to the theory, spacetime is filled with a sea of Higgs bosons, which together form the Higgs field. This particle sea forms a kind of syrup, through which particles such as electrons, quarks and Z-bosons wade through. The stronger the interaction with the Higgs bosons, the slower the particles, in other words the heavier they are. Photons and gluons do not react at all with Higgs particles, making them massless. W and Z particles react very strongly, making them very heavy.
Using the Higgs mechanism, particle physicists have succeeded in predicting the masses of the then undiscovered top and down quark, as well as the W and Z particles. When these particles were actually discovered, the measured masses were found to agree with the predicted values. This earned the discoverers and predictors several Nobel Prizes and is in itself a strong argument for the existence of the Higgs field.
The theoretical disadvantages of the Higgs field
The Higgs field consists of particles with mass (according to the latest estimates, a Higgs boson has a mass around 125 GeV / c2: approx. 133x as heavy as a proton, so about an atom of a heavy element like barium), yet spacetime is massless. This “problem” is usually solved by a mathematical trick: renormalization, which means that infinities are crossed off against each other.
The Higgs boson is also a scalar boson with zero spin. This means that it has no direction, cannot have speed, and the effects of the Higgs field do not depend on location or speed.
In my opinion, the main argument against the Higgs boson is that the Higgs boson is in fact unnecessary. Mass is something that can also be generated through interactions with virtual particles. In fact, photons can also acquire a virtual mass by sending them through a transparent material. Nevertheless, experiments will have the final say.