Topological insulators can be generally defined by a topological field theory with an axion angle θ of 0 or π. In this work, we introduce the concept of fractional topological insulator defined by a fractional axion angle and show that it can be consistent with time reversal (T ) invariance if ground state degeneracies are present. The fractional axion angle can be measured experimentally by th...

In this paper, we introduce a variation of the wellstudied Yao graphs. Given a set of points S ⊂ R and an angle 0 < θ ≤ 2π, we define the continuous Yao graph cY (θ) with vertex set S and angle θ as follows. For each p, q ∈ S, we add an edge from p to q in cY (θ) if there exists a cone with apex p and aperture θ such that q is the closest point to p inside this cone. We study the spanning ratio...

We study the pair description of heavy tetraquark systems $|QQ\overline{Q}\overline{Q}?$ in frame a nonrelativistic potential model. By taking two quark pairs $(Q\overline{Q})$ as colored clusters, four-quark Schr\"odinger equation is reduced to two-pair equation, when inner motion inside can be neglected. Taking into account all Casimir scaling potentials between quarks and using lattice QCD s...

OBJECTIVE Comparison of two methods for evaluation of anatomical parameters of elbow joints in Bernese Mountain Dogs. STUDY DESIGN Radiographic analysis. ANIMALS Nine hundred and thirty-one radiographs of elbow joints from 305 Bernese Mountain Dogs. MATERIAL AND METHODS The angles OL, PA, RA and UL were measured according to the Mues method and the Radius of the humeral condyle, Opening a...

We cast the q-rotor in the framework of Barnett-Pegg theory for rotation angle, whose underlying algebra is SUq(2). A new method to fix the deformation parameter from the theory is suggested. We test our ideas by fitting rotational spectra in deformed even-even and superdeformed nuclei. The results are in good agreement with the previous phenomenological applications of q-rotor model.

A billiard ball, i.e. a point mass, moves inside a polygon Q with unit speed along a straight line until it reaches the boundary ∂Q of the polygon, then instantaneously changes direction according to the mirror law: “the angle of incidence is equal to the angle of reflection,” and continues along the new line (Fig. 1(a)). Despite the simplicity of this description there is much that is unknown ...

In the title compound, C21H22N2O, the planes of the two six-membered rings make a dihedral angle of 89.51 (7)°. The pyrrolidine ring has a puckering amplitude q 2 = 0.418 (3) and a pseudo-rotation phase angle ϕ2 = -166.8 (5), adopting a twist conformation (T). The other five-membered ring has a puckering amplitude q 2 = 0.247 (2) and a pseudo-rotation phase angle ϕ2 = -173.7 (5), adopting an en...

The paper concerns with the study of the modulation diversity in PSK scheme due to rotation of the signal constellation along with bit interleaving. We derive here the expressions for the Symbol Error Probability (SEP) of rotated BPSK and QPSK modulations over frequency non-selective slowly fading Nakagami-q channels. Numerical results based on moment generating function (MGF) are obtained and ...