14,257 research outputs found
Multilayer Graphene Synthesized by CVD Using Liquid Hexane as the Carbon Precursor
We produce multilayer graphene by the Chemical Vapor Deposition (CVD) method
at atmospheric pressure and 1000 {\deg}C, using flexible copper substrates as
catalyst and liquid hexane as the source of carbon. We designed an optical
device to measure the transmittance of the carbon films; with this information
we calculate that the approximate number of layers is 11.Comment: 6 pages, 5 figures. Accepted for publication in World Journal of
Condensed Matter Physic
Resource costs for fault-tolerant linear optical quantum computing
Linear optical quantum computing (LOQC) seems attractively simple:
information is borne entirely by light and processed by components such as beam
splitters, phase shifters and detectors. However this very simplicity leads to
limitations, such as the lack of deterministic entangling operations, which are
compensated for by using substantial hardware overheads. Here we quantify the
resource costs for full scale LOQC by proposing a specific protocol based on
the surface code. With the caveat that our protocol can be further optimised,
we report that the required number of physical components is at least five
orders of magnitude greater than in comparable matter-based systems. Moreover
the resource requirements grow higher if the per-component photon loss rate is
worse than one in a thousand, or the per-component noise rate is worse than
. We identify the performance of switches in the network as the single
most influential factor influencing resource scaling
On the prevalence of racial discrimination in the United States.
Boutwell, Nedelec, Winegard, Shackelford, Beaver, Vaughn, Barnes, & Wright (2017) published an article in this journal that interprets data from the Add Health dataset as showing that only one-quarter of individuals in the United States experience discrimination. In Study 1, we attempted to replicate Boutwell et al.s findings using a more direct measure of discrimination. Using data from the Pew Research Center, we examined a large sample of American respondents (N = 3,716) and explored the prevalence of discrimination experiences among various racial groups. Our findings stand in contrast to Boutwell et al.s estimates, revealing that between 50% and 75% of Black, Hispanic, and Asian respondents (depending on the group and analytic approach) reported discriminatory treatment. In Study 2, we explored whether question framing affected how participants responded to Boutwells question about experiencing less respect and courtesy. Regardless of question framing, non-White participants reported more experiences than White participants. Further, there was an interaction of participant race and question framing such that when participants were asked about experiences of less respect or courtesy broadly, there were no differences between non-White participants and White participants, but when they were asked about experiences that were specifically race-based, non-White participants reported more experiences than White participants. The current research provides a counterweight to the claim that discrimination is not a prevalent feature of the lives of minority groups and the serious implications this claim poses for research and public policy
MOND as the weak-field limit of an extended metric theory of gravity
We show that the Modified Newtonian Dynamics (MOND) regime can be fully
recovered as the weak-field limit of a particular theory of gravity formulated
in the metric approach. This is possible when Milgrom's acceleration constant
is taken as a fundamental quantity which couples to the theory in a very
consistent manner. As a consequence, the scale invariance of the gravitational
interaction is naturally broken. In this sense, Newtonian gravity is the
weak-field limit of general relativity and MOND is the weak-field limit of that
particular extended theory of gravity.Comment: To appear in the proceedings of the 2011 Spanish Relativity Meeting
(ERE2011) held in Madrid, Spain, 4 page
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