Desert (particle physics)
Encyclopedia
In particle physics
, the desert refers to a theorized gap in energy scales between the TeV
scale and the GUT scale in which no new physics appears. The idea of the desert was motivated by the observation of approximate, order of magnitude, gauge coupling unification at the GUT scale. Adding additional new physics at an intermediate scale generically disrupts the gauge coupling unification. With the Minimal Supersymmetric Standard Model
particle content, adjustment of parameters can make this unification exact. This unification is not unique, since alternative scenarios like the Katoptron model
can also lead to exact unification after a similar energetic desert.
If neutrino masses are due to a seesaw mechanism
, the seesaw scale should lie within the desert.
The attraction of a desert is that, in such a scenario, measurements of TeV
scale physics at the near-future colliders LHC
and ILC
will allow extrapolation all the way up to the GUT scale. An alternative to a desert is a series of new physical theories unfolding with every few orders of magnitude increase in energy scale.
Particle physics
Particle physics is a branch of physics that studies the existence and interactions of particles that are the constituents of what is usually referred to as matter or radiation. In current understanding, particles are excitations of quantum fields and interact following their dynamics...
, the desert refers to a theorized gap in energy scales between the TeV
TEV
TEV may refer to:* TeV, or teraelectronvolt, a measure of energy* Total Enterprise Value, a financial measure* Total Economic Value, an economic measure* Tobacco etch virus, a plant pathogenic virus of the family Potyviridae....
scale and the GUT scale in which no new physics appears. The idea of the desert was motivated by the observation of approximate, order of magnitude, gauge coupling unification at the GUT scale. Adding additional new physics at an intermediate scale generically disrupts the gauge coupling unification. With the Minimal Supersymmetric Standard Model
Minimal Supersymmetric Standard Model
The Minimal Supersymmetric Standard Model is the minimal extension to the Standard Model that realizes supersymmetry, although non-minimal extensions do exist. Supersymmetry pairs bosons with fermions; therefore every Standard Model particle has a partner that has yet to be discovered...
particle content, adjustment of parameters can make this unification exact. This unification is not unique, since alternative scenarios like the Katoptron model
Mirror matter
In physics, mirror matter, also called shadow matter or Alice matter, is a hypothetical counterpart to ordinary matter.Modern physics deals with three basic types of spatial symmetry: reflection, rotation and translation. The known elementary particles respect rotation and translation symmetry but...
can also lead to exact unification after a similar energetic desert.
If neutrino masses are due to a seesaw mechanism
Seesaw mechanism
In theoretical physics, the seesaw mechanism is a mechanism within grand unification theory, and in particular in theories of neutrino masses and neutrino oscillation, where it can be used to explain the smallness of observed neutrino masses relative to those of quarks and leptons.There are several...
, the seesaw scale should lie within the desert.
The attraction of a desert is that, in such a scenario, measurements of TeV
TEV
TEV may refer to:* TeV, or teraelectronvolt, a measure of energy* Total Enterprise Value, a financial measure* Total Economic Value, an economic measure* Tobacco etch virus, a plant pathogenic virus of the family Potyviridae....
scale physics at the near-future colliders LHC
Large Hadron Collider
The Large Hadron Collider is the world's largest and highest-energy particle accelerator. It is expected to address some of the most fundamental questions of physics, advancing the understanding of the deepest laws of nature....
and ILC
International Linear Collider
The International Linear Collider is a proposed linear particle accelerator. It is planned to have a collision energy of 500 GeV initially, and, if approved after the project has published its Technical Design Report, planned for 2012, could be completed in the late 2010s. A later upgrade to 1000...
will allow extrapolation all the way up to the GUT scale. An alternative to a desert is a series of new physical theories unfolding with every few orders of magnitude increase in energy scale.