scholarly journals Protective Measurement—A New Quantum Measurement Paradigm: Detailed Description of the First Realization

2021 ◽  
Vol 11 (9) ◽  
pp. 4260
Author(s):  
Enrico Rebufello ◽  
Fabrizio Piacentini ◽  
Alessio Avella ◽  
Rudi Lussana ◽  
Federica Villa ◽  
...  
Keyword(s):  
Quantum Measurement ◽  
Single Particle ◽  
Weak Interactions ◽  
Sharp Contrast ◽  
Protection Mechanism ◽  
Expectation Value ◽  
Measurement Protocol ◽  
Quantum Technology ◽  
First Time ◽  
Measured State

We present a detailed description of the experiment realizing for the first time a protective measurement, a novel measurement protocol which combines weak interactions with a “protection mechanism” preserving the measured state coherence during the whole measurement process. Furthermore, protective measurement allows finding the expectation value of an observable, i.e., an inherently statistical quantity, by measuring a single particle, without the need for any statistics. This peculiar property, in sharp contrast to the framework of traditional (projective) quantum measurement, might constitute a groundbreaking advance for several quantum technology related fields.

scholarly journals Unraveling the long-pursued Au144 structure by x-ray crystallography

2018 ◽  
Vol 4 (10) ◽  
pp. eaat7259 ◽  
Author(s):  
Nan Yan ◽  
Nan Xia ◽  
Lingwen Liao ◽  
Min Zhu ◽  
Fengming Jin ◽  
...  
Keyword(s):  
Metal Nanoparticles ◽  
Weak Interactions ◽  
Gold Nanoclusters ◽  
Atomic Level ◽  
High Quality ◽  
X Ray ◽  
X Ray Crystallography ◽  
Quantum Size ◽  
First Time

The transition from nanocluster to nanocrystal is a central issue in nanoscience. The atomic structure determination of metal nanoparticles in the transition size range is challenging and particularly important in understanding the quantum size effect at the atomic level. On the basis of the rationale that the intra- and interparticle weak interactions play critical roles in growing high-quality single crystals of metal nanoparticles, we have reproducibly obtained ideal crystals of Au144(SR)60 and successfully solved its structure by x-ray crystallography (XRC); this structure was theoretically predicted a decade ago and has long been pursued experimentally but without success until now. Here, XRC reveals an interesting Au12 hollow icosahedron in thiolated gold nanoclusters for the first time. The Au–Au bond length, close to that of bulk gold, shows better thermal extensibility than the other Au–Au bond lengths in Au144(SR)60, providing an atomic-level perspective because metal generally shows better thermal extensibility than nonmetal materials. Thus, our work not only reveals the mysterious, long experimentally pursued structure of a transition-sized nanoparticle but also has important implications for the growth of high-quality, single-crystal nanoparticles, as well as for the understanding of the thermal extensibility of metals from the perspective of chemical bonding.

scholarly journals SoK: Privacy-Preserving Collaborative Tree-based Model Learning

2021 ◽  
Vol 2021 (3) ◽  
pp. 182-203
Author(s):  
Sylvain Chatel ◽  
Apostolos Pyrgelis ◽  
Juan Ramón Troncoso-Pastoriza ◽  
Jean-Pierre Hubaux
Keyword(s):  
Learning Algorithm ◽  
Information Leakage ◽  
Privacy Preserving ◽  
Machine Learning Techniques ◽  
Model Learning ◽  
Protection Mechanism ◽  
Knowledge Based ◽  
Learning Techniques ◽  
Efficient Machine ◽  
First Time

Abstract Tree-based models are among the most efficient machine learning techniques for data mining nowadays due to their accuracy, interpretability, and simplicity. The recent orthogonal needs for more data and privacy protection call for collaborative privacy-preserving solutions. In this work, we survey the literature on distributed and privacy-preserving training of tree-based models and we systematize its knowledge based on four axes: the learning algorithm, the collaborative model, the protection mechanism, and the threat model. We use this to identify the strengths and limitations of these works and provide for the first time a framework analyzing the information leakage occurring in distributed tree-based model learning.

Crystal structure and enantiomeric layer disorder of a copper(I) nitrate π-coordination compound

2021 ◽  
Vol 77 (2) ◽  
Author(s):  
Dorota A. Kowalska ◽  
Vasyl Kinzhybalo ◽  
Yuriy I. Slyvka ◽  
Marek Wołcyrz
Keyword(s):  
Coordination Compound ◽  
Local Structure ◽  
Diffuse Scattering ◽  
Weak Interactions ◽  
The Novel ◽  
X Ray Diffraction ◽  
X Ray ◽  
Structure Solution ◽  
First Time ◽  
Layer Disorder

The novel π-coordination compound [CuI(m-dmphast)NO3], where m-dmphast = 5-(allylthio)-1-(3,5-dimethylphenyl)-1H-tetrazole, is characterized using single-crystal X-ray diffraction and crystallizes in a noncentrosymmetric space group. Additionally, for the first time in this group of materials, the streaks of X-ray diffuse scattering in the reciprocal space sections were observed and described. This gave the possibility for a deeper insight into the local structure of the title compound. The conjecture about the origin of diffuse scattering was derived from average structure solution. It was then confirmed using the local structure modelling. The extended [Cu(m-dmphast)NO3]∞ chains, connected by weak interactions, produce layers which can exist in two enantiomeric forms, one of which predominates.

scholarly journals Laser illumination-induced dramatic catalytic activity change on Au nanospheres

2019 ◽  
Vol 10 (22) ◽  
pp. 5793-5800 ◽  
Author(s):  
Zhongju Ye ◽  
Lin Wei ◽  
Lehui Xiao ◽  
Jianfang Wang
Keyword(s):  
Catalytic Activity ◽  
Symmetry Breaking ◽  
Gold Nanoparticle ◽  
Single Particle ◽  
Catalytic Properties ◽  
Activity Change ◽  
Laser Illumination ◽  
Single Particle Level ◽  
Particle Level ◽  
First Time

In this work, the distinct catalytic properties of a single gold nanoparticle (GNP) after symmetry breaking were disclosed at the single-particle level for the first time.

Hajo Holborn: A Memoir

1970 ◽  
Vol 3 (1-2) ◽  
pp. 3-8
Author(s):  
Felix Gilbert
Keyword(s):  
Sharp Contrast ◽  
Striking Difference ◽  
Decision To Leave ◽  
German Politics ◽  
Foreign Office ◽  
Sunny Weather ◽  
Severe Shock ◽  
First Time

I MET Hajo Holborn for the first time in the fall of 1923 in the archives of the German Foreign Office. Holborn then was finishing his dissertation and editing the Radowitz papers. This first encounter was followed by many brief and hurried talks amid the files of the German Foreign Office: Holborn showed me an exciting note by Bismarck which he had just discovered, or we talked about German politics. I remember vividly a gloomy morning after the election of Hindenburg as President, which gave a severe shock to those who had set their hopes on the development of a democratic Germany. On walks in Heidelberg where Holborn became a Privatdozent in 1926 I could observe how the southern softness of this corner of Germany enchanted this quiet and deliberate North German and I felt happily confirmed in my pride in my native Baden. Perhaps because of the striking difference my next clear recollections of meetings with Holborn are again those of walks, this time in Hyde Park in London on summer afternoons of 1934. The Londoners' joyful surrender to the rare pleasures of sunny weather stood in sharp contrast to the disquieting news from the Continent on which conversation inevitably turned and which confirmed—more convincingly than anyone could have wished—the correctness and necessity of the decision to leave Germany. But I remember that I admired Holborn's ability to shake off the worry about the events in Germany and to study attentively the English life which surrounded him.

STUDY OF SINGLE-PARTICLE RESONANT STATES

2004 ◽  
Vol 19 (20) ◽  
pp. 1537-1545 ◽  
Author(s):  
SHISHENG ZHANG
Keyword(s):  
Single Particle ◽  
Effective Interaction ◽  
Random Phase ◽  
Mean Field ◽  
Coupling Constant ◽  
Relativistic Mean Field ◽  
Resonant States ◽  
Scattering Phase ◽  
First Time ◽  
Phase Shift Method

Energies and widths for single-particle resonant states in the continuum in 120 Sn , as the necessary input quantities of relativistic random phase approximation for the investigation of isoscalar giant octupole resonance, are determined by analytic continuation in the coupling constant (ACCC) method within the framework of self-consistent relativistic mean field (RMF) theory for the first time. For the effective interaction NL3, the results in this scheme agree well with those of scattering phase shift method on the basis of RMF. Similar calculations are carried out in neutron-rich nucleus 84 Ni .

Towards addressing the current state of confusion within the Hexabothriidae Price, 1942 (1908): Callorhynchocotyle Suriano & Incorvaia, 1982 (Monogenea: Hexabothriidae) re-visited, with the preliminary evaluation of novel parameters for measuring haptoral armature of hexabothriids

Zootaxa ◽  
2012 ◽  
Vol 3229 (1) ◽  
pp. 1 ◽  
Author(s):  
DAVID VAUGHAN ◽  
KEVIN CHRISTISON
Keyword(s):  
Multivariate Analyses ◽  
Preliminary Evaluation ◽  
Insufficient Data ◽  
Diagnostic Significance ◽  
Significant Treatment ◽  
Current State ◽  
Measurement Protocol ◽  
The Family ◽  
Variable Character ◽  
First Time

The monogenean family, Hexabothriidae Price, 1942 (1908), currently consists of 15 valid genera parasitic on the gills ofchondrichthyan fishes. The hexabothriid literature is littered with inconsistencies, ambiguity and editorial errors whichhampers the progress and the development of investigations after the significant treatment of the family by Boeger &Kritsky (1989). A lack of consistency in the measurement protocol for the haptoral armature of hexabothriids is highlight-ed and discussed. The preliminary results of a new measurement protocol incorporating existing and novel parameterswere explored for the first time using statistical analyses. Character variables were investigated for their utility as poten-tially useful discriminators using univariate and multivariate analyses. The elimination of age-associated variance in suck-er sclerites was performed by ratio-transformation of the data to an age-dependant variable. Character variables with ahigh coefficient of variance after accounting for age were disqualified for use in the subsequent analyses. A coefficient ofvariance exceeding a conservative 10% limit was considered the result of measurement error resulting from the small sizesof these variables and therefore may also reflect the limitations of hardware and software in making small but accuratemeasurements. The proposed protocol is tested on representatives of Callorhynchocotyle and a Rajonchocotyle species totest the utility of character variables in separating species. Principle Component Analysis of the combination of the sucker-sclerites and the hamulus provided a preliminary level of robustness in separating Callorhynchocotyle species with theexception of Callorhynchocotyle hydrolagi for which there were insufficient data. Results confirm the importance of thehamulus in providing valuable diagnostic significance but the shape of the sucker sclerites as a function of total length anddiameter may also provide significant potential. Callorhynchocotyle is revisited with the addition of new specimens for 3of the species. The new data resulting from the measurement protocol are included in the redescription of Callorhynchoc-otyle marplatensis, Callorhynchocotyle callorhynchi and Callorhynchocotyle amatoi. Supplemental information is provided for C. hydrolagi and Callorhynchocotyle sagamiensis.

scholarly journals BOUND-STATE/ELEMENTARY-PARTICLE DUALITY IN THE HIGGS SECTOR AND THE CASE FOR AN EXCITED "HIGGS" WITHIN THE STANDARD MODEL

2013 ◽  
Vol 28 (28) ◽  
pp. 1350103 ◽  
Author(s):  
AXEL MAAS
Keyword(s):  
Elementary Particle ◽  
Standard Model ◽  
Cross Sections ◽  
Bound States ◽  
Weak Interactions ◽  
Higgs Sector ◽  
Bound State ◽  
Leading Order ◽  
Expectation Value ◽  
The Standard Model

Though being weakly interacting, QED can support bound states. In principle, this can be expected for the weak interactions in the Higgs sector as well. In fact, it has been argued long ago that there should be a duality between bound states and the elementary particles in this sector, at least in leading order in an expansion in the Higgs quantum fluctuations around its expectation value. Whether this remains true beyond the leading order is being investigated using lattice simulations, and support is found. This provides a natural interpretation of peaks in cross-sections as bound states. This would imply that (possibly very broad) resonances of Higgs and W and Z bound states could exist within the Standard Model.

Quantum Technology: Where to Look for the Quantum Measurement Problem

1995 ◽  
Vol 38 ◽  
pp. 73-83
Author(s):  
Nancy Cartwright
Keyword(s):  
Quantum Mechanics ◽  
Quantum Measurement ◽  
Philosophy Of Technology ◽  
Measurement Problem ◽  
Mathematical Structure ◽  
Point Of View ◽  
Philosophy Of Physics ◽  
Unitary Operators ◽  
Quantum Technology ◽  
Philosophical Importance

This paper, I am afraid, advocates the philosophy of technology without actually doing it. It can best be seen as a plea for the philosophical importance of technology; in this case, importance to one of the most widely discussed problems in philosophy of physics—the measurement problem in quantum mechanics. What I want to do here is to lay out a point of view that takes the measurement problem out of the abstract mathematical structure of theory, where we discuss questions about unitary operators or conditions for the disappearance of certain inner products supposed to represent interference terms, and locate it elsewhere. Where is the measurement problem? Answer: It had better be found in the quantum technology or it is not to be found at all. My view in many respects follows ideas I have learned from Willis Lamb.

scholarly journals Engineering proteinaceous colloidosomes as enzyme carrier for efficient and recyclable Pickering interfacial biocatalysis

2021 ◽  
Author(s):  
To Ngai ◽  
Hang Jiang ◽  
Xiaofeng Hu ◽  
Yunxing Li ◽  
Cheng Yang
Keyword(s):  
Single Particle ◽  
Emulsion System ◽  
First Time

Despite Pickering interfacial biocatalysis has been a popular topic in biphasic biocatalysis, the water-in-oil (w/o) emulsion system stabilized by single particle remains a challenge. For the first time, hydrophobized proteinaceous...

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