M. Denissenya

Symmetries of mesons after unbreaking of chiral symmetry and their string interpretation

Using the chirally invariant overlap Dirac operator we remove its lowest-lying quasizero modes from the valence quark propagators and study evolution of isovector mesons with J=1. At the truncation level about 50 MeV SU(2)_L \times SU(2)_R and U(1)_A symmetries get restored. However, we observe a degeneracy not only within the chiral and U(1)_A multiplets, but also a degeneracy of all possible chiral multiplets, i.e., the observed quantum levels have a symmetry larger than U(2)_L \times U(2)_R and their energy does not depend on the spin orientation of quarks and their parities. We offer a possible interpretation of these energy levels as the quantum levels of the dynamical QCD string. The structure of the radial J=1 spectrum is compatible with E =(n_r +1)\hbar\omega with \hbar\omega = 900 \pm 70 MeV.

Cosmic curvature tested directly from observations

Cosmic spatial curvature is a fundamental geometric quantity of the Universe. We investigate a model independent, geometric approach to measure spatial curvature directly from observations, without any derivatives of data. This employs strong lensing time delays and supernova distance measurements to measure the curvature itself, rather than just testing consistency with flatness. We define two curvature estimators, with differing error propagation characteristics, that can crosscheck each other, and also show how they can be used to map the curvature in redshift slices, to test constancy of curvature as required by the Robertson-Walker metric. Simulating realizations of redshift distributions and distance measurements of lenses and sources, we estimate uncertainties on the curvature enabled by next generation measurements. The results indicate that the model independent methods, using only geometry without assuming forms for the energy density constituents, can determine the curvature at the

Subpercent accurate fitting of modified gravity growth

\sim6\times10^{-3}

Testing the SU(4) degeneracy after low-mode removal with J = 2 mesons

level.

Mesons upon low-lying Dirac mode exclusion

Adding to our previous method for dealing with gravitational modifications at redshift

More effects of Dirac low-mode removal

z\gtrsim3

Effects of Low vs. High Fermionic Modes on Hadron Mass Generation

through a single parameter, we investigate treatment of lower redshift modifications to linear growth observables. We establish subpercent accurate fits to the redshift space distortion observable

Isoscalar mesons upon unbreaking of chiral symmetry

f\sigma_8(a)

Emergence of a new

using two parameters binned in redshift, testing the results for modifications with time dependence that rises, falls, is nonmonotonic, is multipeaked, and corresponds to

SU(4)

f(R)