Search results
Results from the WOW.Com Content Network
In particle physics, the doublet–triplet (splitting) problem is a problem of some Grand Unified Theories, such as SU(5), SO(10), and .Grand unified theories predict Higgs bosons (doublets of ()) arise from representations of the unified group that contain other states, in particular, states that are triplets of color.
Examples of atoms in singlet, doublet, and triplet states.. In quantum mechanics, a doublet is a composite quantum state of a system with an effective spin of 1/2, such that there are two allowed values of the spin component, −1/2 and +1/2.
The ability of positronium to form both singlet and triplet states is described mathematically by saying that the product of two doublet representations (meaning the electron and positron, which are both spin-1/2 doublets) can be decomposed into the sum of an adjoint representation (the triplet or spin 1 state) and a trivial representation (the ...
Examples of atoms in singlet, doublet, and triplet states. In quantum mechanics, a triplet state, or spin triplet, is the quantum state of an object such as an electron, atom, or molecule, having a quantum spin S = 1. It has three allowed values of the spin's projection along a given axis m S = −1, 0, or +1, giving the name "triplet".
This is known as the doublet–triplet (DT) splitting problem: In order to be consistent we have to 'split' the 'masses' of and , but for that we need to fine-tune and . There are however some solutions to this problem (see e.g. [ 3 ] ) which can work quite well in SUSY models.
Unfortunately, this same 10 also contains triplets. The masses of the doublets have to be stabilized at the electroweak scale, which is many orders of magnitude smaller than the GUT scale whereas the triplets have to be really heavy in order to prevent triplet-mediated proton decays. See doublet-triplet splitting problem.
These theories predict that for each electroweak Higgs doublet, there is a corresponding colored Higgs triplet field with a very small mass (many orders of magnitude smaller than the GUT scale here). In theory, unifying quarks with leptons, the Higgs doublet would also be unified with a Higgs triplet. Such triplets have not been observed.
Zeeman splitting of the 5s level of 87 Rb, including fine structure and hyperfine structure splitting. Here F = J + I , where I is the nuclear spin (for 87 Rb, I = 3 ⁄ 2 ). This animation shows what happens as a sunspot (or starspot) forms and the magnetic field increases in strength.