XI—The Identification of Klein's Quartic

Author(s):  
W. L. Edge

SummaryThere is a mode of specialising a quartic polynomial which causes a binary quartic to become equianharmonic and a ternary quartic to become a Klein quartic, admitting a group of 168 linear self-transformations. The six relations which must be satisfied by the coefficients of the ternary quartic were given by Coble forty years ago, but their true significance was never suspected and they have remained until now an isolated curiosity. In § 2 we give, in terms of a quadric and a Veronese surface, the geometrical interpretation of the six relations; we also give, in terms of the adjugate of a certain matrix, their algebraical interpretation. Both these interpretations make it abundantly clear that this set of relations specialising a ternary quartic has analogues for quartic polynomials in any number of variables, and point unmistakably to what these analogues are.That a ternary quartic is, when so specialised, a Klein quartic is proved in §§ 4–6. The proof bifurcates after (5.3); one branch leads instantly to the standard form of the Klein quartic while the other leads to another form which, on applying a known test, is found also to represent a Klein quartic. One or two properties of the curve follow from this new form of its equation. In §§ 8–10 some properties of a Veronese surface are established which are related to known properties of plane quartic curves; and these considerations lead to a discussion, in § 11, of certain hexads of points associated with a Klein curve.

2004 ◽  
Vol 32 (1) ◽  
pp. 56-72 ◽  
Author(s):  
Stephen J. Morse

How to respond justly to the dangers persistent violent offenders present is a vexing moral and legal issue. On the one hand, we wish to reduce predation; on the other, we want to treat predators fairly. The central theme of this paper is that it is difficult to achieve both goals without compromising one of them, and that both are being seriously undermined. I begin by explaining the legal theory, doctrine and practice governing dangerous offenders (DO) and demonstrate that the law leaves a gap in the ability to confine them. Next I explore the means by which the law has overtly or covertly sought to fill the gap. Many of these measures, especially the new form of civil commitment for sexual predators, dangerously conflate moral and medical categories. I conclude that pure preventive detention is more common than we usually assume, but that this practice violates fundamental assumptions concerning liberty under the American constitutional regime.


Koedoe ◽  
1975 ◽  
Vol 18 (1) ◽  
Author(s):  
N. I. Passmore ◽  
V. C. Carruthers

A new species of Tomoptema, T. krugerensis, sp. n., has been recorded from the Kruger National Park, Republic of South Africa.Morphologically it is very similar to T. delalandei cryptotis (Boulenger) but the mating call is markedly different from that of the other members of the genus and this is coupled with small but consistent morphological differences.T. krugerensis sp. n. is known to occur only on a portion of the western fringe of the vast sandveld areas of Mozambique, but possibly has a much wider distribution. Mating call, calling behaviour, eggs, early development and defence mechanisms are described. The affinities of the new form are discussed and the mating calls of other members of the genus are reviewed. Mating call is again shown to be a sensitive non-morphological taxonomic tool.


2018 ◽  
Vol 12 (3) ◽  
pp. 589-606 ◽  
Author(s):  
BYEONG-UK YI

AbstractThis article examines two syllogistic arguments contrasted in an ancient Chinese book, the Mozi, which expounds doctrines of the Mohist school of philosophers. While the arguments seem to have the same form, one of them (the one-horse argument) is valid but the other (the two-horse argument) is not. To explain this difference, the article uses English plural constructions to formulate the arguments. Then it shows that the one-horse argument is valid because it has a valid argument form, the plural cousin of a standard form of valid categorical syllogisms (Plural Barbara), and argues that the two-horse argument involves equivocal uses of a key predicate (the Chinese counterpart of ‘have four feet’) that has the distributive/nondistributive ambiguity. In doing so, the article discusses linguistic differences between Chinese and English and explains why the logic of plural constructions is applicable to Chinese arguments that involve no plural constructions.


Author(s):  
Duncan Bell

This chapter examines how historical time was conceptualized in imperial debate. It explores two broad variations that were articulated across the human sciences and in public debate, focusing in particular on the writings of historians. In the first, the modern British empire was figured as uniquely progressive, as capable—either in actuality or in potentia—of avoiding the social, economic, and political dynamics that had annihilated all previous specimens. This argument was most frequently employed in relation to India. The other strategy was to insist that the empire (or a part of it) was not really an empire at all, but rather a new form of political order that could circumvent the entropic degeneration of traditional imperial forms. To think otherwise was to make a category mistake. This argument was often applied to Britain and its settler colonies from the 1870s onwards. “Greater Britain,” as the settler colonial assemblage was often termed, could attain permanence, a kind of historical grace.


Experiment ◽  
2017 ◽  
Vol 23 (1) ◽  
pp. 173-185
Author(s):  
Ekaterina Bobrinskaya

Abstract The paper deals with anti-Western motifs in Russian avant-garde culture, especially their refraction in Russian futurism. On the one hand, the tendency is linked to a strategic goal—asserting independent versions of this or that new form of art and, on the other, it coincides with fundamental features of Russian modernism such as archaization, national self-identification and Eastern cultures.


1986 ◽  
Vol 26 (1) ◽  
pp. 102
Author(s):  
P.C. Reid

Australia's offshore petroleum legislation is the product of a constitutional compromise enshrined in the Offshore Constitutional Settlement of 1979 between the Commonwealth and the States. Whilst it is current Federal Australian Labor Party policy to dismantle the Offshore Constitutional Settlement and re-assert exclusive Commonwealth jurisdiction from the low-water mark seawards, the Hawke Labor Government has been reluctant to implement this particular policy.A practical consequence of the Offshore Constitutional Settlement for the industry is that many offshore titles are now being split into two separate titles — one under State legislation within the three-mile territorial sea and the other under Commonwealth legislation for the Adjacent Area beyond the territorial sea. The Commonwealth proposal to introduce cash bonus bidding for highly prospective offshore exploration permits after being defeated in the Senate in the first half of 1985 was subsequently passed in November 1985.An APEA proposal for the introduction of a new form of title under the Petroleum (Submerged Lands) Act (PSLA) to protect currently non-commercial reserves has been adopted by legislation.Following the cash bidding debate the Commonwealth Minister has proposed a new set of guidelines for the award of offshore permits which will contain both a fixed dry-hole commitment plus a discretionary program in the event of technical encouragement.The paper concludes with some recommendations for establishing a more secure and certain system of title under the PSLA and to minimize the current administrative delays being experienced by industry. Finally it urges that the current level of consultation between Government and industry on matters of interest arising under the PSLA should be allowed to continue.


2019 ◽  
Vol 45 (9-10) ◽  
pp. 1069-1083
Author(s):  
Nadia Urbinati

Before proceeding, I would like to clarify briefly two interpretative premises, one methodological and one normative, which sustain my argument. Understanding the transformations facing constitutional democratic societies is a demanding task. These transformations, whose multiple causes are socio-economic not merely political, reflect on the one hand in the decline of mass party form of organization and on the other in the success of populism as not simply a movement of contestation but as a ruling power. In this article, I will suggest that the successes of populism are connected to the decline of organized parties, the pillar of constitutional democracy as it emerged after 1945. It is impossible to predict whether populism will succeed in becoming the new form of democracy. It is, however, certain that contemporary representative governments are facing astonishing mutations and the decline of the party form of representative unification of claims and ideas is one of them. My argument relies upon a phenomenology of populism as a movement that is strong in proportion as organized parties are weak, which actually capitalizes on a revolt against intermediary bodies such as parties. 1


2015 ◽  
Vol 16 (6) ◽  
pp. 1771-1790 ◽  
Author(s):  
Samo Bardutzky

In 2012 and 2013, we observed how the European Stability Mechanism (ESM) was adjudicated by “EU courts, plural”: a number of high courts of the Member States (among them “Kelsenian” constitutional courts as well as representatives of a more hybrid model of judicial review of constitutionality) and the European Court of Justice (CJEU) were seized by challenges to the mechanism. What attracted attention was the fact that only one court, the Supreme Court of Ireland, decided to submit a preliminary reference to the CJEU, while the other courts, as would appear from their judgments, did not even consider the option. This was a suboptimal example of judicial dialogue in the case of ESM adjudication.


2004 ◽  
Vol 12 (3) ◽  
pp. 267-271 ◽  
Author(s):  
H. L. WESSELING

Words can be confusing and titles can be misleading, particularly if titles consist of one simple word. Two titles suffice to illustrate this phenomenon. In 2000, a book appeared with the title Empire and in 2002 another book appeared with exactly the same title. In the first Empire, Michael Hardt, an American literary theorist, and Antonio Negri, an Italian political philosopher, argued that although classical imperialism is over, Empire is alive and well, albeit in a new form. For them ‘Empire’ means the following: ‘Our basic hypothesis is that sovereignty has taken a new form, composed of a series of national and supranational organisms united under a single logic of rule. This new global form of sovereignty is what we call Empire.’ This is a rather special definition of Empire because what one usually has in mind when using that word is something very different. It is the Empire that the other book, written by the British historian Niall Ferguson, is about. This book describes, as the subtitle indicates, The Rise and Demise of the British World Order. But it is also about something more, as is apparent from the rest of the subtitle: and the Lessons for Global Power. These lessons are intended for the rulers of the Empire of today, the Americans. While the first Empire is the Bible for anti-globalists, Ferguson's book can be considered as the New Testament of the advocates of America's imperial ambitions.


1980 ◽  
Vol 43 (329) ◽  
pp. 605-614 ◽  
Author(s):  
Robert Muir Wood

SummaryZussmanite has been found at only one locality: the Laytonville Quarry, Mendocino County, California. There are, however, present at this locality, two separate, but apparently inter-related minerals that from the evidence of chemistry, and limited diffraction information, appear to be zussmanite-type species. Their relative structural similarities are demonstrated within two rocks from the quarry in which a manganese concentration gradient has allowed ferrous-iron-rich zussmanites to develop partly contiguous overgrowths of one or other of these two minerals, one of which is a new form that has a provisionally determined ideal formula of KAlMn3−5Si17O42(OH)14 and that is separated from ideal zussmanite compositions (of the form KAlSi17O42(OH)14) by an immiscibility gap. The other ‘zussmanite-type’ mineral has a composition that closely resembles a manganese-rich form of minne-sotaite.The first zussmanite-type species (ZU2) has been separated and not unambiguous diffraction information obtained of its cell dimensions and powder lines, which are similar to those of zussmanite but appear to have an 8 % smaller cell-base and only a two-layer repeat (as in some of the zussmanite polytypes, and as in the talc structure). It is therefore considered possible that ZU2 has an altered compatibility between the tetrahedral and octa-hedral sheet overlap, perhaps from 13 (as in zussmanite) to 12. Whilst zussmanite appears to be a blueschist-eclogite mineral, ZU2 occurs under conditions at the low-pressure side of the blueschist facies.An intermediate between zussmanite and the manganoan ‘minnesotaite’ is found in one rock in which the rims of zussmanite have been leached of potassium. As minnesotaite is more of a range of compositions than a structure (there is mounting evidence that it is not a simple talc-analogue) a consideration of the Laytonville manganoan minnesotaite as a zussmanite mineral is not unreasonable.


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