66,741 research outputs found
A ZX-Calculus with Triangles for Toffoli-Hadamard, Clifford+T, and Beyond
We consider a ZX-calculus augmented with triangle nodes which is well-suited
to reason on the so-called Toffoli-Hadamard fragment of quantum mechanics. We
precisely show the form of the matrices it represents, and we provide an
axiomatisation which makes the language complete for the Toffoli-Hadamard
quantum mechanics. We extend the language with arbitrary angles and show that
any true equation involving linear diagrams which constant angles are multiple
of Pi are derivable. We show that a single axiom is then necessary and
sufficient to make the language equivalent to the ZX-calculus which is known to
be complete for Clifford+T quantum mechanics. As a by-product, it leads to a
new and simple complete axiomatisation for Clifford+T quantum mechanics.Comment: In Proceedings QPL 2018, arXiv:1901.09476. Contains Appendi
The contribution of CHONS particles to the diffuse high Galactic latitude IR emission
This work purports to model the far infrared gray-body emission in the
spectra of high-Galactic-latitude clouds. Several carbonaceous laboratory
materials are tested for their fitness as carriers of this modified-black-body
emission which, according to data delivered by the Planck satellite, and others
before, is best fit with temperature 17.9 K and spectral index beta=1.78. Some
of these materials were discarded for insufficient emissivity, others for
inadequate beta. By contrast, CHONS clusters (beta=1.4, T=19 K) combine nicely
with magnesium silicate (beta=2, T=18.7 K) to give a spectrum which falls well
within the observational error bars (total emission cross-section at 250 mum:
8.6 10^{-26} cm^{2} per H atom). Only 15 % of all Galactic carbon atoms are
needed for this purpose. The CHONS particles that were considered and described
have a disordered (amorphous) structure but include a sizable fraction of
aromatic rings, although they are much less graphitized than a-C:H/HAC. They
can be seen as one embodiment of ``astronomical graphite" deduced earlier on
from the then available astronomical observations. Grain heating by H atom
capture is proposed as a contributor to the observed residual emissions that do
not follow the dust/HI correlation.Comment: 11 pages, 13 figures To be published in MNRA
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