Impossible Result Research Articles

Helmholtz equation for a Neumann condition on a curved boundary: spurious resonances

The 2D canonical case of a semi-circular canyon is addressed via two types of boundary-integral equations (BIE) methods which are shown, via Galerkin procedures, to lead to matrix equations with kernels that vanish at two different sets of (what appear as resonant) frequencies. This physically impossible result is interpreted as being the sign that the two BIE methods are generally defective and that the resonances are ‘spurious’. This ‘disease’ is cured by combining two BIE's into one which gives rise to a closed-form solution identical to the exact separation-of-variables solution devoid of resonances.

Light at the museum – A near impossible result

The monitoring and quantification of the illegal harvest of protected animal products is very vital for the conservation and protection of endangered species. Most of the methods and techniques used in the trade of these products are recognised to be incredibly time consuming and labour intensive requiring significant analyst expertise. In this study, we have demonstrated the potential of near-infrared spectroscopy combined with either principal component analysis or partial least square discriminant analysis regression as a rapid and non-invasive tool to classify horn and ivory samples stored in the Australian Museum, Sydney. This study has also demonstrated the attractiveness of the near-infrared technique as a screening tool that could revolutionise the tracking and identification of contraband materials produced from horn and ivory biomaterials.

Randomized quantum oblivious transfer with application in hacker-resistant computation

OT (Oblivious transfer) is a fundamental primitive in cryptography. But it is well known that in quantum cryptography, unconditionally secure OT is impossible. A variant of OT, i.e. randomized OT, is presented. We then show how to realize this variant in quantum cryptography with some security relaxations, which is inevitable because of the well-known impossible result in quantum cryptography. We also present a new secure computational model, namely HRC (Hacker-Resistant Computation) model. Since on today’s Internet there are more and more hackers and increased cyber threat, knowing how to protect the information and privacy stored on our computer and on cloud servers is very important, even when the computer or server has been breached by hackers. Finally, some interesting applications of the randomized OT variant to HRC are discussed.

Cryptanalysis and improvement of a quantum private set intersection protocol

A recent Quantum Private Set Intersection (QPSI) scheme is crypt-analyzed. The original claimed communication overhead is shown to be not accurate. And the original security definition is passive and not fair. To ensure fairness, a passive third party is introduced. It is also shown that unconditional fairness of QPSI protocol is impossible. Since otherwise, it would violate a well-known impossible quantum cryptography result.

Separating sheep from goats: a European view on the patent eligibility of biomedical diagnostic methods

The Supreme Court’s decisions in Mayo, Myriad and Alice, as well as the CAFC’s in Roslin focused widespread attention on the formulation of patent-eligibility exclusions for specific biological material and diagnostic methods. The debate recently intensified with the CAFC’s Sequenom decision and denial of a rehearing en banc. The claims at issue in U.S. Patent No. 6,258,540 (“US ’540 patent”) are directed to methods of genetic testing by detecting and amplifying paternally inherited fetal cell-free DNA (cffDNA) from maternal blood and plasma. Before the development of this non-invasive prenatal diagnostic test, patients were placed at higher risk and maternal plasma was routinely discarded as waste. A reluctant CAFC formulaically interpreted the Supreme Court-devised bifurcated test to identify patent ineligible subject matter and invalidated the patent for this ground-breaking method. Notably, Judge Linn wrote that this innovation deserves patent protection, but that the “sweeping language of the test” established in Mayo requires a determination that the claims are patent ineligible. On March 21, 2016 Sequenom Inc. filed for certiorari and the issue may once again find itself at the Supreme Court. As framed by Sequenom, the question presented is: Whether a novel method is patent-eligible where: (1) a researcher is the first to discover a natural phenomenon; (2) that unique knowledge motivates him to apply a new combination of known techniques to that discovery; and (3) he thereby achieves a previously impossible result without preempting other uses of the discovery? Interestingly, in Europe the EPO upheld essentially the same claims. European equivalents of the patents considered in Myriad, Mayo, Alice and Roslin were also treated differently than in the US. Hence, these cases undermine the global integration of patent standards and provide fodder for discussing patentability requirements at an international level. Referring to these developments, our paper discusses these issues from a comparative European perspective. Section 1 provides a very brief summary of the European patent framework and case law regarding medical diagnostic methods. Leaving aside national peculiarities that would exceed the limitations of this study we focus on the EPO’s patent eligibility approach vis-a-vis medical diagnostic methods similar to those in Sequenom v. Ariosa. Section 2 discusses our findings and the differences between the US and European approaches from a broader innovation and patent policy perspective providing the basis for concluding remarks in section 3.

A further discussion on the effective thermal conductivity of metal foam: An improved model

In this study, we explain the causes and effects of the geometrical impossible result encountered in the widely adopted tetrakaidecahedron model (Boomsma and Poulikakos, 2001; Dai et al., 2010) for the effective thermal conductivities (ETCs) of metal foam. The geometrical impossible result is successfully eliminated by accounting for the size variation of the node with porosity. The improved model provides predictions of ETCs that are more precise than available models. For aluminum foams (ks=218Wm-1K-1) using water and air as fluid media, the relative root-mean-square (RMS) deviation of the present predictions from the experimental data is about 5.3%; for the reticulated vitreous carbon (RVC) foams (ks=8.5Wm-1K-1), the relative RMS deviation is about 7.4%.

Aragonite cements around methane seeps: Comment

Lithified rocks underlie extensive stretches of the Atlantic continental shelfoff the eastern United States. A sample of shelly sandstone resembling beachrock and cemented by aragonite wasrecovered from thisshelfat a depth of79 moff the New Jersey coast (lat, 38OZ2'N, long. 73°45'W). The radiocarbonageofthemolluscan shells is439O±120yearsand that of the cement is 15,6OO±250 years. At first sight, the radiocarbon agesgivewhatappears tobe an impossible result: cementation of "young" shellsby "old" cement Assuming that the radiocarbon measurements are correct, they require someexplanation. Onepossible waytoexplain theminvokes the idea that the actual precipitation of the cementoccurred less than4390 years ago, but that thecarbon in the aragonite didnotcomedirectly outofseawater (inwhich casethecarbon would be "new", that is, 4390 years old), but was rather derived from a sourceof older carbon. Analyses of stablecarbon isotopes showthat the cement is enriched in the light stableisotope(12C); its513C valueis -44.8. Thiscontrasts with a 013C value of -8.4for themolluscan shells of therock. The strongly negative 013C value of the cement suggests that carbon of thearagonite cementcamefrom methane (CH.J; no other material is known in which the lighter carbon isotope has been that much enriched. Although such strongly negative 513C values are diagnostic of methane, diagenetic processes ultimately will restore a normal isotopic composition (Friedman, 1975). Photographs of thesecements are given in papers by Allen et al. (1969) andFriedman et al. (1971).

Methane-derived authigenic carbonates formed by subduction-induced pore-water expulsion along the Oregon/Washington margin: Discussion and reply

Methane-derived authigenic carbonates in terrigenous sediments described from the Pacific Ocean along the Oregon/Washington margin (Ritger and others, 1987) have their counterparts in the outer continentalshelf setting of the western Atlantic Ocean. Lithified sandstones, containing a modern microfauna and resulting from submarine cementation, underlie extensive stretches of the shelf between New Jersey and Florida (Allen and others, 1969; Friedman, 1975; Friedman and others, 1971; Friedman and Sanders, 1978, esp. p. 157-158). In a dredged shelly molluscan sandstone, the radiocarbon age of the molluscan shells is 4,390 ± 120 yr and that of cement is 15,600 ± 250 yr. At first sight, the radiocarbon ages give what appears to be an impossible result: cementation of young shells by old cement. To explain these ages, one may invoke the idea that the actual precipitation of the cement occurred less than 4,390 yr ago but that the carbon in the aragonite did not come directly out of sea water (in which case, the carbon would be new, that is, 4,390 yr old) and rather was derived from a source of older carbon. Analyses of stable-carbon isotopes show that the cement is enriched in the light stable isotope 12C; its S13C value is -44.8. This contrasts with a S13C value of -8.4 for the molluscan shells of the rock. The strongly negative 613C value of the cement suggests that carbon of the aragonite cement came from methane (CH4) (Allen and others, 1969; Friedman and others, 1971; Friedman, 1975); no other material is known in which the lighter carbon isotope has been that much enriched. The stable isotopic compositions of cement and skeletal carbonates overlap with those of the Oregon/Washington margin (Fig. 7, p. 151 of Ritger and others, 1987).

Master of Judicial Wisdom

He was always alert to detect cant, hypocrisy, or pettifogging. He had an innate sense that told him when a seemingly irrefragable legal argument was leading to an impossible result, and was therefore necessarily flawed; a conclusion he often telegraphed with the terse observation, ain't law wonderful. More than anything else, however, what made him one of the very great judges was his judicial wisdom. A scholar's knowledge of American institutions and deep understanding of the nature of the judicial process, both tempered with good common sense, gave him a mastery of the proper limits of judicial power--of the limited role even the best judge may properly play in a democratic society. Because his wisdom accurately defined that role for him, he could effectively play it to the hilt. One of the most important tasks of a state supreme court justice is to interpret and enforce the Constitution of the United States and of his own state. Justice Traynor of course wrote many outstanding opinions in this area.' He fought valiantly to have the court make sense of the powers of administrative agencies to find facts;2 a battle not to be won until after he had left the court.3 He was constantly concerned with the meaning of the constitutional provision prohibiting reversal of a judgment for error unless the error resulted in a miscarriage of jus-

Dyson Maleev transformation in ferromagnets with single ion planar anisotropy

We show that the Dyson Maleev (DM) transformation can be applied to the Heisenberg ferromagnet with single ion planar anisotropy, although the resulting bilinear part of the bosonic equivalent normally ordered Hamiltonian is not hermitian. With respect to the approaches adopted up to this moment, that is, the Holstein Primakoff (HP) transformation and the matching matrix elements (MME) method, the DM transformation offers relevant advantages because it generates a finite number of interaction potentials, so we are able to obtain the second-order perturbation contributions of the excitation energy, a practically impossible result to get in the HP and MME frame. In this communication we discuss the problem and show the main results; details of the very long, cumbersome calculations will be given elsewhere.

A generalized dynamic flows problem

AbstractThe original maximal dynamic flows problem is to find the maximal flow that may be transferred within a given period of time, from the source to the destination of a network with constant edge capacities and lengths. This paper generalizes the problem in two ways. First, the edge's capacity is time dependent, and secondly, the heldover of flows in the vertices may be prohibited during certain intervals of time. The presence of these two additional features implies that cycling of flows may be necessary in order to generate an optimal solution, an impossible result in the original problem. The generalized maximal dynamic flows problem requires, therefore, a special method of solution, and the paper presents a suitable algorithm which solves the problem.

On the velocity and temperature distributions in the turbulent wake behind a heated body of revolution

Thevelocity distributionin the wake behind a body of revolution calculated by Miss Swain on the momentum transfer theory withlconstant over a cross-section of the wake is not in accordance with experiment.On the generalized vorticity transfer theory the equation for the first approximation to the velocity defectufar downstream isThere are two methods of simplifying this equation on the analogy of the successful simplification of the corresponding equation for the two-dimensional case. One method gives the same equation as if the turbulence were symmetrical; the other gives the equation of the modified vorticity transfer theory.For the former there is no real solution iflis constant over a cross-section; for a real solutionlmust be infinite on the axis of symmetry. The equation was integrated withl∝r−1over a cross-section; this variation oflwas suggested by putting the change in the area enclosed by a circular vortex-line proportional to the area of the section of the wake. The agreement with experiment is fairly good over the middle portion of the wake, but not near the edge, where the theoretical value of ∂u/∂ris not zero. Ifl2∝rp, ∂u/∂rvanishes at the edge of the wake only ifp= − 3. The solution is carried through for this case; it shows only fair agreement with experiment over the middle of the wake, and none at the edge.The calculation on the modified vorticity transfer theory is carried out withlconstant over a section; in this case there is no definite edge to the wake, nor doesufall off sufficiently rapidly to make the momentum integral for the drag converge. (u∝r−2for larger.) Even over the middle of the wake there is a discrepancy with experimental results, rather like that shown by the momentum transfer theory.Thetemperature distributionbehind a heated body was calculated according to each of the foregoing theories.The temperature distribution was also calculated from the experimental velocity distribution, without any assumption being made concerning the kinematic coefficient of turbulent diffusion, which was eliminated between the equations for the velocity and temperature. The vorticity transfer theory with symmetrical turbulence gives an impossible result. The modified vorticity transfer theory gives θ/θmax<u/umaxwhen the experimental velocity distribution is used.