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The difficult choice for the Nobel Prize in Physics: Discoveries of planets outside the solar system or the existence of the Higgs boson?

And in addition to them, those who discovered superconductors based on the element iron are also measured, or maybe none of them? Next week we will know

The "god particle" or maybe the cursed particle. Illustration: shutterstock
"The God Particle" Or maybe the damn particle. Illustration: shutterstock

The candidates for the 2013 Nobel Prize in Physics
1. Planets outside the solar system
Geoffrey Marcy, Professor of Astronomy, University of California, Berkeley, California, USA, Michel Muir, Professor Emeritus, University of Geneva, Geneva, Switzerland and Didia Cloz, Queloz, Professor, University of Cambridge, Cambridge, England , United Kingdom and Professor at the University of Geneva, Geneva, Switzerland The three researchers are nominated for the 2013 Nobel Prize in Physics for: "Discoveries of extrasolar planets".
For hundreds of years thinkers have grappled with the philosophical question of the possibility of the existence of worlds worthy of human habitation that are outside the solar system. Copernicus and Galileo made the multiplicity of worlds an acceptable idea, which found avid followers in the form of the philosopher John Locke, the astronomer William Herschel, the well-known scientist Benjamin Franklin and other great thinkers. At the same time, extrasolar planets, or as they are called 'exoplanets', are so tiny and so pale in their emitted light compared to their parent stars that their existence was no more than an amusing hypothesis.

In 1995, scientists Michel Mayor and Didier Queloz of the University of Geneva announced the discovery of a massive exoplanet orbiting the star 51 Pegasi, visible to the naked eye under very dark sky conditions. In order to discover the planet, the researchers used the radial velocity method: a planet moving in its orbit causes its parent star to make a small shift around the center of mass of the system, when this rotation can be detected by the Doppler output. For the star 51 Pegasi, the deviation value is about one hundred meters per second. The planet causing this disturbance completes its orbit in only 4.2 days. Verification of the discovery came from Geoffrey Marcy, who was able to obtain the spectra of the system at the Lick Observatory in California.

Marcy and his colleagues discovered the largest number of exoplanets compared to any other research team. The notable findings of his research group include the first multi-planetary system which was the double (binary) star 'Epsilon' in the constellation 'Andromeda' and the first planets close to the size of the planets Saturn and Jupiter. Marcy is a co-investigator on NASA's Kepler space mission which has managed to discover several thousand stars with exoplanets. The verified findings include Earth-like planets that are in the host region of their parent stars. Marcy's discoveries suggest that the Milky Way galaxy contains at least 100 billion exoplanets.

2. Superconductors based on the element iron
Hideo Hosuno, Professor in the Laboratory of Materials and Structures and Director of the Materials Research Center for Foundation Strategy, Tokyo Institute of Technology, Yokohama, Japan. The researcher is nominated for the 2013 Nobel Prize in Physics for: "Discoveries of iron-based superconductors".

In superconductors the electrical resistance suddenly drops to zero when the temperature of the material drops below the critical temperature (Tc). This phenomenon was discovered in 1911 by the Dutch physicist Heike Kamerlinge Onnes when he measured the conductivity of a solid mercury wire immersed in liquid helium. Many decades later, physicists still believed that the highest temperature of superconductivity would be around 30 degrees Kelvin (minus 243.15 degrees Celsius) only.

Everything changed in 1986 with the discovery of superconductors composed of copper-based ceramic materials (cuprates). These materials have a complex structure where the main component is a superconducting layer of copper oxide. The most famous superconductor among this family of materials is the material copper-yttrium-barium oxide [YBa2Cu3O7] which has a critical temperature that is higher than the temperature of 77 degrees Kelvin (around minus 196 degrees Celsius), which is the boiling point of liquid nitrogen. The discovery of this material paved the way for large-scale applications, such as the high current conducting electrical cables used in the particle accelerator located at the CERN research center on the Switzerland-France border.
The discovery of high critical temperature copper oxides has accelerated a vigorous research effort into layered systems containing non-copper transition metal ions. This effort did indeed lead to the discovery of a number of superconductors, but in all of them the critical temperature was far below those found in the copper oxides.
In 2008 Hideo Hosono and his colleagues stumbled upon the accidental discovery of a completely new type of superconducting material family named oxypnictide: a layered compound of iron-lanthanum-arsenic oxide [LaAsFeO] doped with fluorine and having a critical temperature of 26 degrees Kelvin (around minus 247.15 degrees Celsius). This discovery was made during their research on improvements in transparent semiconductors based on metal oxides that were required in the field of photovoltaic devices, but they led to a breakthrough in discovering the first layered superconductor based on the metal iron. Materials scientists dismissed the possibility of iron-based superconductivity, arguing that iron's large magnetic moment would be destructive to copper's electron pairs responsible for superconductivity. The discovery led to a burst of activity in the field of iron-based superconductors, and within a few months the highest critical temperature measured was 50 degrees Kelvin (around minus 223.15 degrees Celsius).

3. Braut-Englert-Higgs boson
Francois Englert, Professor Emeritus, Free University of Brussels (ULB), Brussels, Belgium, and Visiting Professor at the Institute for Quantum Studies, Chapman University, Orange, California USA and Peter Higgs, Professor Emeritus, University of Edinburgh, Scotland, United Kingdom Second The researchers are nominated for the 2013 Nobel Prize in Physics for: "Their predictions regarding the possibility of the existence of the Braut-Englert-Higgs boson".

In 1964 the theoretical physicists Francois Englert and Robert Braut of the Free University of Brussels and Peter Higgs of the University of Edinburgh separately proposed a solution to the big question: What gives matter its mass? This weighty conundrum lies at the heart of the Standard Model in particle physics given the fact that the greater the particle's mass, the shorter the range it reacts with other particles and forces.

A basic version of the theory of particle physics holds that the particles called bosons, which are responsible for the interactions of the weak force, should be massless. However, it seems that this is not the case: the discovered W and Z bosons have a mass one hundred times greater than the proton, a mass greater even than the mass of the iron atom.

It is not unusual for a physical law to be disproven because the established hypothesis as to its symmetry or threshold conditions no longer hold, or from a certain point. For example, Newton's laws cease to hold at speeds where relativistic effects become significant. This situation led physicists to understand that under certain conditions a mechanism could exist that cancels the effects of the laws of symmetry in the field of particle physics.

The researchers Braut and Englert took the first step in August of 1964 when they showed that bosons could have mass if an unusual type of force field emerges in the space in which they are located, causing the breaking of the symmetry governing the weak nuclear force. Their short article showed that in the case of symmetry breaking the resulting field will not necessarily lead to massless particles.

In October of that year (1964), the researcher Higgs reached the same conclusion, separately, using the classical theory.
The Higgs Mechanism is a theoretical model that describes the process by which elementary particles gain mass. They do this through their interaction with the Higgs field which is present throughout space. On a side note, Higgs stated that his conclusions regarding the mechanism by which particles gain mass are only hypotheses. At the same time, he predicted the existence of a boson with zero mass and zero spin.

The discovery of the Braut-Engelert-Higgs boson will prove that the standard model is indeed correct. However, it took four whole decades from the moment of the prediction until its practical discovery, apparently, in the large particle accelerator in Switzerland.
Note - the scientist Braut died last year, so he is not a candidate for the Nobel Prize.

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