Nuclear, Particle, Astroparticle and Cosmology (NUPAC) Seminars
NUPAC Seminar
Presented by Kevin Cahill, UNM
Intrinsically broken symmetries of general relativity, tensor Yang-Mills fields and dark matter
The action of general relativity with fermions has two independent symmetries: general-coordinate invariance and local Lorentz invariance. These local symmetries are intrinsically broken by the nonzero average values of the tetrads which reduce the independent symmetries of general-coordinate invariance and local gauge invariance to a single exact symmetry — local Lorentz invariance.
In standard general relativity, local Lorentz invariance is implemented by the spin connection. Here local Lorentz invariance is implemented by spin-two gauge fields and a real vector boson which must be timelike in order for the gauge-field action to be bounded below. The vector boson is neutral and massive, and contributes to dark matter.
The invariances of general relativity with fermions are extended from general-coordinate invariance and local Lorentz invariance to general-coordinate invariance and local U(2,2) invariance.
If the contracted squares of the covariant derivatives of the tetrads multiplied by the square of a mass M are added to the action, then in the limit M → ∞ the equation of motion of the spin- two gauge fields is the vanishing of the covariant derivatives of the tetrads, which is Cartan’s first equation of structure. In the same limit, the spin-two gauge fields are the spin connection.
2:00 pm, Tuesday, January 24, 2023
Zoom,
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