A Dark-Matter Candidate Mass from the Carrier Ladder: Torsion-Only Annihilation Against the Relic Density

If a fermion from the carrier ladder is the dark matter, its abundance must be set by some depletion process. This paper tests the minimal possibility that torsion contact interactions alone set the relic density, using the standard thermal-relic relation between annihilation rate and present abundance. The torsion-mediated rate, suppressed by powers of the carrier mass over the Planck mass, is far too small for every Standard Model carrier on the ladder, from the electron to the tau. Each would be overproduced by many orders of magnitude. A ladder fermion can therefore be the dark matter only if another interaction depletes it, or if its abundance was set non-thermally, for example at a bounce, with the yield computed separately. Headline values are: sigma v required m3 s = 3.000e-32, overproduction tau = 1.809e+67, overproduction electron = 2.187e+74, overproduction neutron = 6.468e+67. This study is simulated and computed from stated assumptions; it is not a measurement.