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1.
Summary Continuing the program initiated in the first paper of this series, representations of the Lie algebra
of the Poincaré group
are constructed by forming suitable direct integrals of representations of SL(2, C) and extending them to
by means of four additional momentum operators whose matrix elements are derived in a basis adapted to the direct integral
structure. The representations obtained here include Wigner’s representations with positive mass and spin
and Wigner’s representations with zero mass, spin
and helicity ±
.
Lavoro eseguito con contributo del C.N.R. nell’ambito dell’attività di ricerca del Gruppo Nazionale per la Fisica Matematica
e per le applicazioni della Matematica alla Fisica ed all’Ingegneria.
Entrata in Redazione il 12 marzo 1972. 相似文献
2.
Arthur Moór 《Annali di Matematica Pura ed Applicata》1961,54(1):255-273
Zusammenfassung Das invariante Differential eines Vektors
ist selbst ein Vektor, der vom Orte xi, von dxi,
und von
selbst abh?ngig ist. Es wird nun infolge dieser Definition in einigen F?llen die m?gliche Form des invarianten Differentials
bestimmt.
Enrico Bompiani zu seinem wissenschaftlichen Jubil?um. 相似文献
3.
Summary Quaternion generalized fiber bundles
are studied, both isomorphic to global tensorial product
ordinary quaternion fiber bundles right and left respectively) and quite general ones. A cohomology class
is considered which represents the obstruction in order the fiber bundle be a tensorial product. Several properties and a
splitting principle are proved for bundles
. On this ground and founding on a convenient bundle BE → X associated to jaz (that we call Bonan's bundle and for which ɛ(
=ɛ(BE)) relations are stated among Stiefel-Whitney classes of
, BE and the class ɛ.
Entrata in Redazione il 14 agosto 1974.
Lavoro eseguito con contributo del C.N.R., nell'ambito del Gruppo Nazionale per le Strutture Algebriche e Geometriche e loro Applicazioni. 相似文献
Entrata in Redazione il 14 agosto 1974.
Lavoro eseguito con contributo del C.N.R., nell'ambito del Gruppo Nazionale per le Strutture Algebriche e Geometriche e loro Applicazioni. 相似文献
4.
Summary We study the problem of the existence of bounded solutions for the equation
on pseudo-Siegel domains
when the data
satisfies the condition
.
Work done within the Project 40% M.U.R.S.T. «Geometria Reale e Complessa». 相似文献
Sunto Si studia il problema dell'esistenza di soluzioni limitate per l'equazione sui domini pseudo-Siegel quando il dato soddisfa alla condizione .
Work done within the Project 40% M.U.R.S.T. «Geometria Reale e Complessa». 相似文献
5.
Summary The purpose of this paper is to study the validity of the Paley inequality on square function, for noncommutative martingales.
Let
be a regular gage space, and
a sequence of von-Neumann algebras such that
we prove that for every
, where ɛn(F) is the conditional expectation of F with respect to the subalgebra
: We also consider the case of a martingale arising in the context of harmonic analysis on noncommutative discrete groups,
in analogy to the theorem of R.E.A.C. Paley on Fourier-Walsh series.
Entrata in Redazione il 26 gennaio 1977.
Partially sponsored by C.N.R. 相似文献
6.
Summary Let
a plane angle of opening α∈(π, 2π). LetP
D andP
N the Dirichlet and Neumann problems associated to the Poisson equation in
. ForP
D andP
N it is proved non existence of solution in L
p
(
) whenp=2/(1±π/α). In other words, the ranges of elliptic operators naturally associated toP
D andP
N are not-closed in L
p
(
) forp=2/(1±π/α).
Sunto Sia } un angolo piano di apertura α∈(π, 2π). SianoP D eP N i problemi di Dirichlet e di Neumann associati all'equazione di Poisson in . PerP D eP N si prova non esistenza di soluzioni in L p ( ) quandop=2/(1±π/α). Vale a dire i ranges degli operatori ellittici naturalmente associati aP D eP N sono non-chiusi in π--AgBrα K L p ( ) perp=2/(1±π/α).相似文献
7.
P. Pych-Taberska 《分析论及其应用》1994,10(4):25-36
For measurable functions f of two real variables there are considered the Boolean sums
of parametric extensions of certain univariate Durmeyer-type operators
and
. The weighted mixed moduli of continuity of
are estimated and the degrees of approximation of f by
in some weighted norms are investigated. 相似文献
8.
M. B. Zvyagina 《Journal of Mathematical Sciences》1998,89(2):1122-1126
Let Λ be an associative ring with identity and let
be the category of left unitary Λ-modules. A subcateqory
of the category
is said to be small if the pairwise nonisomorphic objects of
form a set. The main result of this paper consists of the fact that for every small full subcategory
, there exists a ring Γ such that
is dual to a small full subcategory of the category
. Some applications of this result are indicated. Bibliography: 3 titles.
Translated fromZapiski Nauchnykh Seminarov POMI, Vol. 227, 1995, pp. 66–73. 相似文献
9.
Summary It is proved that every entropy with the property of branching has the form
, where J is a compositive information measure under a regular binary operation. In particular all the classical entropies
with the branching property such as that of Shannon have the form
.
Entrata in Redazione il 9 aprile 1973. 相似文献
Sunto Si dimostra che ogni entropia che goda della proprietà di diramazione ha necessariamente la forma dove J è una misura di informazione compositiva con una operazione binaria regolare. In particolare tutte le entropie classiche che godono della proprietà di diramazione quale quella di Shannon hanno la forma .
Entrata in Redazione il 9 aprile 1973. 相似文献
10.
Luise Unger 《manuscripta mathematica》1986,57(1):1-31
Let
be the path algebra for some representation-infinite quiver
over some field k. There exists a bound
such that mI is faithful for all indecomposable injective
-modules I and all
, and such that there exists an indecomposable injective
-module J satisfying that
J is not faithful, denotes the Auslander-Reiten-translation. Let m() be the maximum of the
taken over all possible orientations of the underlying graph . In this article we determine the bounds m() for representation-infinite quivers
for which is a tree. 相似文献
11.
Yasunori Fujikoshi Yoshimichi Ochi 《Annals of the Institute of Statistical Mathematics》1984,36(1):119-128
Summary In this paper we obtain an asymptotic expansion of the distribution of the maximum likelihood estimate (MLE)
based onT observations from the first order Gaussian process up to the term of orderT
−1. The expansion is used to compare
with a generalized estimate
including the least square estimate (LSE)
, based on the asymptotic probabilities around the true value of the estimates up to the terms of orderT
−1. It is shown that
(or the modified MLE
) is better than
(or the modified estimate
). Further, we note that
does not attain the bound for third order asymptotic median unbiased estimates. 相似文献
12.
K. I. Beidar M. Bre@scaron;ar M. A. Chebotar 《Journal of Mathematical Sciences》2000,102(6):4557-4565
Let
, be the algebra of upper triangular r×r matrices over field aF. We describe multilinear maps
, where n≤r, such that [f(A,...,A), A]=0 for all
, provided that |F| >n + 1. As an application of the results obtained, we describe linear automorphisms θ of
such that [θ(A2), θ(A)]=0 for all
.
Translated from Itogi Nauki i Tekhniki, Seriya Sovremennaya Matematika i Ee Prilozheniya. Tematicheskie Obzory. Vol. 74, Algebra-15,
2000. 相似文献
13.
Let
and
be adjoint nilpotent orbits in a real semisimple Lie algebra. Write
≥
if
is contained in the closure of
. This defines a partial order on the set of such orbits, known as the closure ordering. We determine this order for the split
real form of the simple complex Lie algebra, E
8. The proof is based on the fact that the Kostant-Sekiguchi correspondence preserves the closure ordering. We also present
a comprehensive list of simple representatives of these orbits, and list the irreeducible components of the boundaries
and of the intersections
. 相似文献
14.
Cesarina Marchionna Tibiletti 《Annali di Matematica Pura ed Applicata》1978,44(1):251-259
Sunto Dati due gruppi A* e B* e due loro sottogruppi I
A
*
ed I
B
*
fra loro isomorfi in un certo isomorfismo ω si considerano i gruppi G=AB con A e B permutabili fra di loro ed isomorfi rispettivamente
ad A* e B* in modo che I=A∩B sia isomorfo ed I*A ed I*B. Si caratterizzano, in base alla struttura dei gruppi dati, certi gruppi prodotto completo
nei quali sono contenuti (come sottogruppi di tipo ben definito) i suddetti gruppi G=AB (e ciò sotto alcune ipotesi per A*
e B*, che valgono sempre quando A* e B* sono gruppi finiti). Si illustra poi qualche caso in cui i precedenti gruppi
risultano prodotti completi minimi in cui siano contenuti i gruppi G=AB. 相似文献
15.
G. B. Rizza 《Annali di Matematica Pura ed Applicata》1972,92(1):37-63
Sunto Su di una varietà quasi hermitiana V, la considerazione di alcune medie di curvature semplici e miste, relative a convenienti
sistemi di 2-spazi associati ad un 2-spazio α, dà informazioni sulla curvatura semplice Kα, sulla media
e sulla curvatura mista
(
=Jα). Due delle medie accennate riescono nulle; le altre danno luogo a relazioni di dipendenza lineare. Considerate per la
varietà V ipotesi di isotropia in media e di J-isotropia si ottengono teoremi del tipo di Schur. Altri risultati si stabiliscono
nel caso k?hleriano.
Entrata in Redazione il 25 novembre 1971.
Lavoro eseguito con contributo del C.N.R. nell'ambito del Gruppo Nazionale Strutture Algebriche, Geometriche e loro Applicazioni. I primi risultati sono stati annunciati in una riunione di Gruppo a Bologna (dicembre 1970) e in una conferenza tenuta all'Ist. Mat. Univ. Perugia (aprile 1971). 相似文献
Summary Let V be an almost Hermite space, α a tangent 2-dimensional space of V; five systems of tangent 2-spaces of V are considered, suitably related to α. The sectional curvature Kα, the mean value , and the bisectional curvature are expressed in terms of mean values of sectional and bisectional curvatures, evalued over the above mentioned systems. Two of the mean values vanish; linear relationships hold among the other ones. Schur-like theorems are proven under the assumption that V be isotropic in mean or J-isotropic. Further results are obtained for the case that V be a K?hler space.
Entrata in Redazione il 25 novembre 1971.
Lavoro eseguito con contributo del C.N.R. nell'ambito del Gruppo Nazionale Strutture Algebriche, Geometriche e loro Applicazioni. I primi risultati sono stati annunciati in una riunione di Gruppo a Bologna (dicembre 1970) e in una conferenza tenuta all'Ist. Mat. Univ. Perugia (aprile 1971). 相似文献
16.
This paper examines the following question. If
and
are saturated formations then
is defined to be the class of all soluble groups whose
belong to
. In general
is a formation, but need not be a saturated formation. Here the smallest saturated formation containing
is studied. 相似文献
17.
Andrew J. Sommese 《Milan Journal of Mathematics》1997,67(1):49-75
Let
be an algebraic submanifold of complex projective space ℙ
N
. Assume thatn:=dim
and let
denote the restriction of the hyperplane section bundle
to
. The meromorphic map
associated to
fork≥1 ties together the pluricanonical maps of the surface sections of
. Known results show that the behavior of
is far better than one would expect from experience with the pluricanonical mappings of algebraic surfaces. In this article
we discuss the known results on the structure of the mappings
and describe the open problems.
Conferenza tenuta il 5 giugno 1997 相似文献
18.
Sergio Campanato 《Annali di Matematica Pura ed Applicata》1965,69(1):321-381
Summary Regularity results of Schauder type in the class of H?lderian functions are proved for solutions of second order elliptic
equations in the variational form. Morrey and other authors have obtained results of this kind in certain classes of functions
. The method of proof followed here makes use of the classes of functions
which generalize the classes considered by Morrey, and whose properties in relation to H?lder continuity are studied in some
proceeding works.
Ha parzialmente contribuito finanziariamente alla preparazione di questo lavoro l'Air Force Office of Scientific Research OAR con il Grant AF EOAR 65–42. 相似文献
Ha parzialmente contribuito finanziariamente alla preparazione di questo lavoro l'Air Force Office of Scientific Research OAR con il Grant AF EOAR 65–42. 相似文献
19.
Brendan Mc Cann 《Annali di Matematica Pura ed Applicata》1990,157(1):27-61
Summary
We present a Fitting Class construction which exploits the properties of a certain class of finite soluble groups of nilpotent length three, called
-groups in the paper. In addition we look at a wider class of groups, called
in the paper, also of nilpotent length three and examine the question as to what
-groups are in
.A number of examples are given to illuminate the various classes.The author would like to thank HermannHeineken for supervising his dissertation, from which this paper has sprung, the German Academic Exchange Service (DAAD) for enabling him to study with Prof. Heineken at Universität Würzburg and An Roinn Oideachais for the fellowship which is at present supporting him at University College, Galway. 相似文献
20.
Summary We define a notion of contact totally umbilical submanifolds of Sasakian space forms corresponds to those of totally umbilical
submanifolds of complex space forms. We study a contact totally umbilical submanifold M of a Sasakian space form
(c ≠ −3) and prove that M is an invariant submanifold or an anti-invariant submanifold. Furthermore we study a submanifold
M with parallel second fundamental form of a Sasakian space form
(c ≠ 1) and prove that M is invariant or anti-invariant.
Entrata in Redazione il 7 settembre 1976. 相似文献