Bordes, J., Chan, H. M., & Tsou, S. T. (2021). delta(CP) for leptons and a new take on CP physics with the FSM. Int. J. Mod. Phys. A, 36, 2150236–22pp.
Abstract: A bonus of the framed Standard Model (FSM), constructed initially to explain the mass and mixing patterns of quarks and leptons, is a solution (without axions) of the strong CP problem by cancelling the theta-angle term theta(I) Tr(H-mu v H-mu v*) in coloura by a chiral transformation on a quark zero mode which is inherent in FSM, and produces thereby a CP-violating phase in the CKM matrix similar in size to what is observed.' Extending here to flavour, one finds that there are two terms proportional to Tr(G(mu v) G(mu v)*): (a) in the action from flavour instantons with unknown coefficient, say theta(I)', (b) induced by the above FSM solution to the strong CP-problem with therefore known coefficient theta(C)'. Both terms can be cancelled in the FSM by a chiral transformation on the lepton zero mode to give a Jarlskog invariant J' in the PMNS matrix for leptons of order 10(-2), as is hinted by the experiment. But if, as suggested in Ref. 2, the term theta(I)' is to be cancelled by a chiral transformation in the predicted hidden sector to solve the strong CP problem therein, leaving only the term theta(C)' to be cancelled by the chiral transformation on leptons, then the following prediction results: J' similar to -0.012 (delta(CP)'similar to (1.11)pi) which is (i) of the right order, (ii) of the right sign and (iii) in the range favoured by the present experiment. Together with the earlier result for quarks, this offers an attractive unified treatment of all known CP physics.
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Bordes, J., Chan, H. M., & Tsou, S. T. (2021). Unified FSM treatment of CP physics extended to hidden sector giving (i) delta(CP) for leptons as prediction, (ii) new hints on the material content of the universe. Int. J. Mod. Phys. A, 36, 2150238–19pp.
Abstract: A unified treatment of CP physics for quarks and leptons in the framed Standard Model (FSM) is extended to include the predicted hidden sector giving as consequences: (i) that an earlier part estimate of the Jarlskog invariant J' for leptons is turned into a prediction for its actual value, i.e. J' similar to -0.012 (delta(CP)' similar to 1.11 pi), which is of the right order of magnitude, of the right sign, and in the range of values favoured by the present experiment, (ii) some novel twists to the effects of CP-violation on the material content of the universe.
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Flores, M. M., Kim, J. S., Rolbiecki, K., & Ruiz de Austri, R. (2023). Updated LHC bounds on MUED after run 2. Int. J. Mod. Phys. A, 38(1), 2350002–14pp.
Abstract: We present updated LHC limits on the minimal universal extra dimensions (MUEDs) model from the Run 2 searches. We scan the parameter space against a number of searches implemented in the public code CheckMATE and derive up-to-date limits on the MUED parameter space from 13TeV searches. The strongest constraints come from a search dedicated to squarks and gluinos with one isolated lepton, jets and missing transverse energy. In the procedure, we take into account initial state radiation and stress its importance in the MUED searches, which is not always appreciated.
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Gerbino, M. et al, Martinez-Mirave, P., Mena, O., Tortola, M., & Valle, J. W.. (2023). Synergy between cosmological and laboratory searches in neutrino physics. Phys. Dark Universe, 42, 101333–36pp.
Abstract: The intersection of the cosmic and neutrino frontiers is a rich field where much discovery space still remains. Neutrinos play a pivotal role in the hot big bang cosmology, influencing the dynamics of the universe over numerous decades in cosmological history. Recent studies have made tremendous progress in understanding some properties of cosmological neutrinos, primarily their energy density. Upcoming cosmological probes will measure the energy density of relativistic particles with higher precision, but could also start probing other properties of the neutrino spectra. When convolved with results from terrestrial experiments, cosmology can become even more acute at probing new physics related to neutrinos or even Beyond the Standard Model (BSM). Any discordance between laboratory and cosmological data sets may reveal new BSM physics and/or suggest alternative models of cosmology. We give examples of the intersection between terrestrial and cosmological probes in the neutrino sector, and briefly discuss the possibilities of what different laboratory experiments may see in conjunction with cosmological observatories.
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