We present a time-reversal invariant s-wave superconductor supporting Majorana edge modes. The multiband character of the model together with spin-orbit coupling are key to realizing such a topological superconductor. We characterize the topological phase diagram by using a partial Chern number sum, and show that the latter is physically related to the parity of the fermion number of the time-r...

A general method of constructing the Dirac operator for a randomly trian-gulated manifold is proposed. The fermion field and the spin connection live, respectively, on the nodes and on the links of the corresponding dual graph. The construction is carried out explicitly in 2-d, on an arbitrary orientable manifold without boundary. It can be easily converted into a computer code. The equivalence...

The presence of dark energy in the Universe challenges the Einstein’s theory 1 of gravity at cosmic scales. It motivates the inclusion of rotational degrees of freedom in 2 the Einstein-Cartan gravity, representing the minimal and the most natural extension of the 3 General Relativity. One can, consequently, expect the violation of the cosmic isotropy by 4 the rotating Universe. We study chiral...

Spin-orbit coupled superconductors are interesting candidates for realizing topological and potentially nonAbelian states with Majorana fermions. We argue that time-reversal broken spin-orbit coupled superconductors generically can be characterized as having subgap states that are bound to localized nonmagnetic impurities. Such bound states, which are referred to as the Shiba states, can be det...

We discuss the equivalence between the path integral representations of spin dynamics for anti-commuting (Grassmann) and commuting variables and establish a bosonization dictionary for both generators of spin and single fermion operators. The content of this construction in terms of the representations of the spin algebra is discussed in the path integral setting. Finally it is shown how a 'fre...

A general method of constructing the Dirac operator for a randomly trian-gulated manifold is proposed. The fermion field and the spin connection live, respectively, on the nodes and on the links of the corresponding dual graph. The construction is carried out explicitly in 2-d, on an arbitrary orientable manifold without boundary. It can be easily converted into a computer code. The equivalence...

We study the low-energy band structure of armchair and small-band-gap semiconducting carbon nanotubes with proximity-induced superconducting pairing when a spiral magnetic field creates strong effective spin-orbit interactions from the Zeeman term and a periodic potential from the orbital part. We find that gapless Dirac fermions can be generated by variation of a single parameter. For a small-...

We examine an axion string coupled to a Majorana fermion. It is found that there exist a Majorana-Weyl zero mode on the string. Due to the zero mode, the axion strings obey non-abelian statistics. Fermionic zero modes on topological defects often cause non-trivial phenomena in relativistic quantum field theory. Some examples are fermion number fractionalization [1], baryon number violation in t...