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The
promise continues to be fullfilled to AWES researchers mapping
empirical kite-engineering challenges to established science in
multidisciplinary dimensions. The AWESCO project, for example,
specifically includes a PhD researcher to explore kitewing (if not
kitefarm) topology. Moritz himself seems to have been the first to
invoke topology (if not topological protection) in AWE academic
circles. Here on the AWES Forum, we found theoretic energy-kite
lattices meet all formal criteria for "megascale metamaterials" (as do
third-party seismic engineering cases). The following claim seems
hereby justified; that virtually all the principles and effects studied
in Condensed Matter Physics (a very broad field) apply directly to
kite-based systems. Kite physics is neither simple nor
incomprehensible. Just a few years ago we were first pondering what it
meant that our AWES were phononic, and we have come a long way since. The
abstract and diagram below is another recent example of hundreds that
could be offered here as well, but is particularly good for newcomers
to follow the keyword trail to get started (read Wikipedia esp) The
diagram starkly depicts the similarity of the newly emerging science to
our kite lattice concepts, being comprised of the same building blocks
of lines, pulleys, and mass-points (as kites qua anchors, as JoeF
instructs). We increasingly understand the kite in flight as a bosonic
quasi-particle that is not just its body, but includes its entrained
wake and tether-forces. Recall that we have already reviewed
metamaterial papers about arrays of rotating masses acted on by fans.
Complaints that kite, and especially kite latiices, are not subject to
such physics, have subsided in proportion to the growing evidence that
they are. Here is a particularly resonant statement with topological AWE (kite-lattice) analytics presented on the AWES Forum- "Moreover,
the zero-frequency phonon modes feature adjustable momenta and are
topologically protected as long as the lattice coordination is
unchanged. Such
protected soft (topological) modes with tunable wave vector may be
useful in designing mechanical structures with fault-tolerant
properties." Indeed, we are already well along this conceptual path in theoretic AWE. Sadly,
this particular recent paper, whose abstract is below, is stuck behind
a login-wall, but fortunately there are many other open papers from the
last decade or so that similarly inform us in seeing "kitematter" as
fully part of emerging cutting-edge material science- ============== Phonon analog of topological nodal semimetalsHoi Chun Po, Yasaman Bahri, and Ashvin VishwanathPhys. Rev. B 93, 205158 – Published 31 May 2016ABSTRACTTopological
band structures in electronic systems like topological insulators and
semimetals give rise to highly unusual physical properties. Analogous
topological effects have also been discussed in bosonic systems, but
the novel phenomena typically occur only when the system is excited by
finite-frequency probes. A mapping recently proposed by C. L. Kane and
T. C. Lubensky [Nat. Phys. 10, 39 (2014)],
however, establishes a closer correspondence. It relates the
zero-frequency excitations of mechanical systems to topological zero
modes of fermions that appear at the edges of an otherwise gapped
system. Here we generalize the mapping to systems with an intrinsically
gapless bulk. In particular, we construct mechanical counterparts of
topological semimetals. The resulting gapless bulk modes are physically
distinct from the usual acoustic Goldstone phonons and appear even in
the absence of continuous translation invariance. Moreover, the
zero-frequency phonon modes feature adjustable momenta and are
topologically protected as long as the lattice coordination is
unchanged. Such protected soft modes with tunable wave vector may be
useful in designing mechanical structures with fault-tolerant
properties. |
