924 research outputs found
Varieties of liberalism: Anglo-Saxon capitalism in crisis?
‘Global financial crisis’ is an inaccurate description of the current upheaval in the world’s financial markets. The initial banking crisis did not affect all countries to the same degree. Notably, while the US and UK banking systems
were badly hit, those of the other two major Anglo-Saxon economies, Canada and Australia, remain largely unscathed and have even gained in terms of global market share. The national business systems and comparative corporate governance literatures underscore the similarities among these four ‘liberal market economies’ (LMEs) and would predict similar trajectories. This paper investigates the reasons behind the differing performance of the Anglo-Saxon
banking systems, which defy a verdict of failure of the LME variety of capitalism as such
Fermion zero modes at the boundary of superfluid 3He-B
Superfluid 3He-B belongs to the important special class of time-reversal
invariant topological superfluids. It has Majorana fermions as edge states on
the surface of bulk 3He-B. On the rough wall these fermion zero modes have
finite density of states at E=0. It is possible that Lancaster experiments with
a wire vibrating in 3He-B have already probed Majorana fermions living on the
surface of the wire.Comment: 4 pages, no Figures, JETP Letters style, version to be published in
JETP Letter
Twenty years of ‘Law and Finance’: time to take law seriously
This ‘state of the art’ essay provides a comprehensive discussion of the Law and Finance School (LFS) literature. We show that the first two decades of the LFS have focused on empirically investigating the question ‘does law matter?’ Yet, despite the centrality of law to the LFS, it is based on an incoherent theory of law, which leads to shortcomings in the conceptualization and empirical testing of its hypotheses. We also observe that, rather than addressing this deficiency, the LFS has moved its focus to the contentious concept of ‘legal origin’. We argue that the LFS needs to take law more seriously by returning to its initial focus on the substance of legal rules and by addressing the theoretical question ‘how does law matter?’ We propose venues for future research to develop a solid theoretical framework that would put the empirical investigation of law’s impact on economic outcomes on a more solid footing
Spin Berry phase in the Fermi arc states
Unusual electronic property of a Weyl semi-metallic nanowire is revealed. Its
band dispersion exhibits multiple subbands of partially flat dispersion,
originating from the Fermi arc states. Remarkably, the lowest energy flat
subbands bear a finite size energy gap, implying that electrons in the Fermi
arc surface states are susceptible of the spin Berry phase. This is shown to be
a consequence of spin-to-surface locking in the surface electronic states. We
verify this behavior and the existence of spin Berry phase in the low-energy
effective theory of Fermi arc surface states on a cylindrical nanowire by
deriving the latter from a bulk Weyl Hamiltonian. We point out that in any
surface state exhibiting a spin Berry phase pi, a zero-energy bound state is
formed along a magnetic flux tube of strength, hc/(2e). This effect is
highlighted in a surfaceless bulk system pierced by a dislocation line, which
shows a 1D chiral mode along the dislocation line.Comment: 9 pages, 9 figure
Evolution of edge states in topological superfluids during the quantum phase transition
The quantum phase transition between topological and non-topological
insulators or between fully gapped superfluids/superconductors can occur
without closing the gap. We consider the evolution of the Majorana edge states
on the surface of topological superconductor during transition to the
topologically trivial superconductor on example of non-interacting Hamiltonian
describing the spin-triplet superfluid 3He-B. In conventional situation when
the gap is nullified at the transition, the spectrum of Majorana fermions
shrinks and vanishes after the transition to the trivial state. If the
topological transition occurs without the gap closing, the Majorana fermion
spectrum disappears by escaping to ultraviolet, where Green's function
approaches zero. This demonstrates the close connection between the topological
transition without closing the gap and zeroes in the Green's function. Similar
connection takes place in interacting systems where zeroes may occur due to
interaction.Comment: 5 pages, 2 figures, JETP Letters style, version submitted to JETP
Letter
Localization dynamics of fluids in random confinement
The dynamics of two-dimensional fluids confined within a random matrix of
obstacles is investigated using both colloidal model experiments and molecular
dynamics simulations. By varying fluid and matrix area fractions in the
experiment, we find delocalized tracer particle dynamics at small matrix area
fractions and localized motion of the tracers at high matrix area fractions. In
the delocalized region, the dynamics is subdiffusive at intermediate times, and
diffusive at long times, while in the localized regime, trapping in finite
pockets of the matrix is observed. These observations are found to agree with
the simulation of an ideal gas confined in a weakly correlated matrix. Our
results show that Lorentz gas systems with soft interactions are exhibiting a
smoothening of the critical dynamics and consequently a rounded
delocalization-to-localization transition.Comment: 5 pages, 3 figure
Stable Bosonic Topological Edge Modes in the Presence of Many-Body Interactions
Many magnetic materials are predicted to exhibit bosonic topological edge
modes in their excitation spectra, because of the nontrivial topology of their
magnon, triplon or other quasi-particle band structures. However, there is a
discrepancy between theory prediction and experimental observation, which
suggests some underlying mechanism that intrinsically suppresses the expected
experimental signatures, like the thermal Hall current. Many-body interactions
that are not accounted for in the non-interacting quasi-particle picture are
most often identified as the reason for the absence of the topological edge
modes. Here we report stable bosonic edge modes at the boundaries of a ladder
quantum paramagnet with gapped triplon excitations in the presence of the full
many-body interaction. For the first time, we use tensor network methods to
resolve topological edge modes in the time-dependent spin-spin correlations and
the dynamical structure factor, which is directly accessible experimentally. We
further show that these edge modes have anomalously long time coherence,
discuss the topological phase diagram of the model, demonstrate the
fractionalization of its low-lying excitations, and propose potential material
candidates
- …