10,641 research outputs found
Super-Resolution of Mutually Interfering Signals
We consider simultaneously identifying the membership and locations of point
sources that are convolved with different low-pass point spread functions, from
the observation of their superpositions. This problem arises in
three-dimensional super-resolution single-molecule imaging, neural spike
sorting, multi-user channel identification, among others. We propose a novel
algorithm, based on convex programming, and establish its near-optimal
performance guarantee for exact recovery by exploiting the sparsity of the
point source model as well as incoherence between the point spread functions.
Numerical examples are provided to demonstrate the effectiveness of the
proposed approach.Comment: ISIT 201
Miniaturized Computational Photonic Molecule Spectrometer
Miniaturized spectrometry system is playing an essential role for materials
analysis in the development of in-situ or portable sensing platforms across
research and industry. However, there unavoidably exists trade-offs between the
resolution and operation bandwidth as the device scale down. Here, we report an
extreme miniaturized computational photonic molecule (PM) spectrometer
utilizing the diverse spectral characteristics and mode-hybridization effect of
split eigenfrequencies and super-modes, which effectively eliminates the
inherent periodicity and expands operation bandwidth with ultra-high spectral
resolution. These results of dynamic control of the frequency, amplitude, and
phase of photons in the photonic multi-atomic systems, pave the way to the
development of benchtop sensing platforms for applications previously
unfeasible due to resolution-bandwidth-footprint limitations, such as in gas
sensing or nanoscale biomedical sensing
The No-Scale Multiverse at the LHC
We present a contemporary perspective on the String Landscape and the
Multiverse of plausible string, M- and F-theory vacua, seeking to demonstrate a
non-zero probability for the existence of a universe matching our own observed
physics within the solution ensemble, arguing for the importance of No-Scale
Supergravity as an essential common underpinning. Our context is a highly
detailed phenomenological probe of No-Scale F-SU(5), a model representing the
intersection of the F-lipped SU(5) X U(1)_X Grand Unified Theory (GUT) with
extra TeV-Scale vector-like multiplets derived out of F-theory, and the
dynamics of No-Scale Supergravity. We present a highly constrained "Golden"
region with tan(beta) \sim 15, m_t = 173.0 - 174.4 GeV, M_1/2 = 455 - 481 GeV,
and M_V = 691 - 1020 GeV, which simultaneously satisfies all known experimental
constraints. We supplement this bottom-up phenomenological perspective with a
top-down theoretical analysis of the one-loop effective Higgs potential,
achieving a striking consonance via the dynamic determination of tan(beta) and
M_1/2 at the local secondary minimization of the spontaneously broken
electroweak Higgs vacuum V_min. We present the distinctive signatures of
No-Scale F-SU(5) at the LHC, where a light stop and gluino are expected to
generate a surplus of ultra-high multiplicity (>= 9) hadronic jet events. We
propose modest alterations to the canonical background selection cut strategy
which would enhance resolution of these events, while readily suppressing the
contribution of all Standard Model processes, and allowing a clear
differentiation from competing models of new physics. Detection by the LHC of
the ultra-high jet signal would constitute a suggestive evocation of the
intimately linked stringy origins of F-SU(5), and could provide a glimpse into
the fundamental string moduli, and possibly even the workings of the No-Scale
Multiverse.Comment: A review of recent work, submitted to the DICE 2010 Workshop
proceedings, based on the invited talk by D.V.N. (20 Pages, 5 Tables, 18
Figures
Entanglement, intractability and no-signaling
We consider the problem of deriving the no-signaling condition from the
assumption that, as seen from a complexity theoretic perspective, the universe
is not an exponential place. A fact that disallows such a derivation is the
existence of {\em polynomial superluminal} gates, hypothetical primitive
operations that enable superluminal signaling but not the efficient solution of
intractable problems. It therefore follows, if this assumption is a basic
principle of physics, either that it must be supplemented with additional
assumptions to prohibit such gates, or, improbably, that no-signaling is not a
universal condition. Yet, a gate of this kind is possibly implicit, though not
recognized as such, in a decade-old quantum optical experiment involving
position-momentum entangled photons. Here we describe a feasible modified
version of the experiment that appears to explicitly demonstrate the action of
this gate. Some obvious counter-claims are shown to be invalid. We believe that
the unexpected possibility of polynomial superluminal operations arises because
some practically measured quantum optical quantities are not describable as
standard quantum mechanical observables.Comment: 17 pages, 2 figures (REVTeX 4
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