scholarly journals Are Virtual Particles Less Real?

Entropy ◽  
2019 ◽  
Vol 21 (2) ◽  
pp. 141 ◽  
Author(s):  
Gregg Jaeger

The question of whether virtual quantum particles exist is considered here in light of previous critical analysis and under the assumption that there are particles in the world as described by quantum field theory. The relationship of the classification of particles to quantum-field-theoretic calculations and the diagrammatic aids that are often used in them is clarified. It is pointed out that the distinction between virtual particles and others and, therefore, judgments regarding their reality have been made on basis of these methods rather than on their physical characteristics. As such, it has obscured the question of their existence. It is here argued that the most influential arguments against the existence of virtual particles but not other particles fail because they either are arguments against the existence of particles in general rather than virtual particles per se, or are dependent on the imposition of classical intuitions on quantum systems, or are simply beside the point. Several reasons are then provided for considering virtual particles real, such as their descriptive, explanatory, and predictive value, and a clearer characterization of virtuality—one in terms of intermediate states—that also applies beyond perturbation theory is provided. It is also pointed out that in the role of force mediators, they serve to preclude action-at-a-distance between interacting particles. For these reasons, it is concluded that virtual particles are as real as other quantum particles.

Parasitology ◽  
2017 ◽  
Vol 144 (9) ◽  
pp. 1162-1178 ◽  
Author(s):  
MOETI O. TAIOE ◽  
MAKHOSAZANA Y. MOTLOANG ◽  
BONIFACE NAMANGALA ◽  
AMOS CHOTA ◽  
NTHATISI I. MOLEFE ◽  
...  

SUMMARYTabanids are haematophagous flies feeding on livestock and wildlife. In the absence of information on the relationship of tabanid flies and protozoan parasites in South Africa and Zambia, the current study was aimed at characterizing tabanid flies collected in these two countries as well as detecting protozoan parasites they are harbouring. A total of 527 tabanid flies were collected whereby 70·2% were from South Africa and 29·8% were from Zambia. Morphological analysis revealed a total of five different genera collected from the sampled areas namely:Ancala, Atylotus, Haematopota, PhilolicheandTabanus. DNA extracted from South AfricanTabanus parandTabanus taeniolatested positive for the presence ofTrypanosoma congolense(Savannah) andTrypanosoma theileriwhilst one member fromT. parwas positive forTrypanosoma bruceispecies. DNA extracted from Zambian tabanid flies tested positive for the presence ofBesnoitiaspecies at 1·27% (2/157),Babesia bigemina5·73% (9/157),Theileria parva30·11% (30/157) and 9·82% (14/157) forTrypanosoma evansi. This study is the first to report on relationship ofBabesiaandTheileriaparasites with tabanid flies. Further investigations are required to determine the role of tabanids in transmission of the detected protozoan parasites in livestock and wildlife in South Africa and Zambia.


2004 ◽  
Vol 54 (2) ◽  
pp. 429-437 ◽  
Author(s):  
Jaime Cubero ◽  
James H. Graham

Characterization of strains of Xanthomonas axonopodis pv. citri by using DNA fingerprints that were generated from primers for enterobacterial repetitive intergenic consensus (ERIC) elements led to the discovery of differential sequences for a leucine-responsive regulatory protein (lrp) gene in two subgroups of strains with different host ranges on Citrus spp. DNA hybridization and PCR-based assays that used different sets of primers were designed to detect the core sequence, as well as to obtain the entire sequence of the lrp gene for several Xanthomonas species and pathovars. Higher variability was observed at the nucleotide level than at the amino acid level among the different species and pathovars, revealing selection pressure on the lrp gene, which is presumably due to an essential role of the gene in bacterial metabolism. Moderate variability in the 3′ and 5′ domains was used to study relationships among different species within the genus Xanthomonas. Species of this genus that were isolated from citrus, as well as other pathovars of X. axonopodis, showed highly similar lrp gene sequences, whereas other Xanthomonas species, especially Xanthomonas campestris, had sequences that were more dissimilar to that of X. axonopodis. Thus, the lrp gene sequence is useful to distinguish X. axonopodis pv. citri groups and promising for polyphasic taxonomic analysis of the genus Xanthomonas. Data from analysis of lrp gene sequences support the current concepts for classification of xanthomonads, which are based on other approaches.


Author(s):  
Alex D. Greenwood ◽  
Yasuko Ishida ◽  
Sean P. O'Brien ◽  
Alfred L. Roca ◽  
Maribeth V. Eiden

SUMMARYViruses of the subfamilyOrthoretrovirinaeare defined by the ability to reverse transcribe an RNA genome into DNA that integrates into the host cell genome during the intracellular virus life cycle. Exogenous retroviruses (XRVs) are horizontally transmitted between host individuals, with disease outcome depending on interactions between the retrovirus and the host organism. When retroviruses infect germ line cells of the host, they may become endogenous retroviruses (ERVs), which are permanent elements in the host germ line that are subject to vertical transmission. These ERVs sometimes remain infectious and can themselves give rise to XRVs. This review integrates recent developments in the phylogenetic classification of retroviruses and the identification of retroviral receptors to elucidate the origins and evolution of XRVs and ERVs. We consider whether ERVs may recurrently pressure XRVs to shift receptor usage to sidestep ERV interference. We discuss how related retroviruses undergo alternative fates in different host lineages after endogenization, with koala retrovirus (KoRV) receiving notable interest as a recent invader of its host germ line. KoRV is heritable but also infectious, which provides insights into the early stages of germ line invasions as well as XRV generation from ERVs. The relationship of KoRV to primate and other retroviruses is placed in the context of host biogeography and the potential role of bats and rodents as vectors for interspecies viral transmission. Combining studies of extant XRVs and “fossil” endogenous retroviruses in koalas and other Australasian species has broadened our understanding of the evolution of retroviruses and host-retrovirus interactions.


1980 ◽  
Vol 34 (5) ◽  
pp. 561-569 ◽  
Author(s):  
R. B. Green ◽  
G. J. Havrilla ◽  
T. O. Trask

The electrical interferences associated with laser-enhanced ionization (LEI) spectrometry are characterized in this study. This was accomplished by comparison of LEI signal behavior in acetylene/air and hydrogen/air flames. A discussion of the relationship of the analytical signal and the total ion concentration in the flame is presented. The results of flame composition experiments are discussed as well as the role of matrix ions in determining signal strength. Experiments with modified sensing electrodes and higher applied voltages illustrate a partial remedy for electrical interferences.


2020 ◽  
pp. 101-114
Author(s):  
Myroslava Lysak

The article is dedicated to the study of semantics and functioning of compound nouns with a somatic component (CNSC) in the German language, in particular, the CNSC in German political discourse within the period from 2016 to 2020. Main semantic and functional features of CNSC are being determined. The article is focused on the role of CNSC in creating a pragmatic effect of publications within the political topics, looks into a powerful manipulative influence on the reader during the formation of a positive image of the politician or his deliberate discrediting, including the possibility of using individual compound nouns with a somatic component in order to ridiculize and undermine his image. The study explores metaphorical and metonymic transfers, on the basis of which the semantics of such compound nous with a somatic component in German political discourse is developing. The investigation presents the classification of a compound nouns with a somatic component into thematic subgroups within the thematic block “Politics”, the relationship of these groups in German-language mass media texts with political items, the semantic evolution of such compound nouns with a somatic component. Compound nouns with a somatic component with positive, negative, and ambivalent connotations which are actualized within the German political discourse, are also being explored. The studied lexical units belong to the dynamic and innovative part of the German lexicon, they represent the creativity of speakers, as well as their aspiration for their speech individualization and its emotional richness.


Author(s):  
D. F. Blake ◽  
L. F. Allard ◽  
D. R. Peacor

Echinodermata is a phylum of marine invertebrates which has been extant since Cambrian time (c.a. 500 m.y. before the present). Modern examples of echinoderms include sea urchins, sea stars, and sea lilies (crinoids). The endoskeletons of echinoderms are composed of plates or ossicles (Fig. 1) which are with few exceptions, porous, single crystals of high-magnesian calcite. Despite their single crystal nature, fracture surfaces do not exhibit the near-perfect {10.4} cleavage characteristic of inorganic calcite. This paradoxical mix of biogenic and inorganic features has prompted much recent work on echinoderm skeletal crystallography. Furthermore, fossil echinoderm hard parts comprise a volumetrically significant portion of some marine limestones sequences. The ultrastructural and microchemical characterization of modern skeletal material should lend insight into: 1). The nature of the biogenic processes involved, for example, the relationship of Mg heterogeneity to morphological and structural features in modern echinoderm material, and 2). The nature of the diagenetic changes undergone by their ancient, fossilized counterparts. In this study, high resolution TEM (HRTEM), high voltage TEM (HVTEM), and STEM microanalysis are used to characterize tha ultrastructural and microchemical composition of skeletal elements of the modern crinoid Neocrinus blakei.


2020 ◽  
Vol 17 (6) ◽  
pp. 76-91
Author(s):  
E. D. Solozhentsev

The scientific problem of economics “Managing the quality of human life” is formulated on the basis of artificial intelligence, algebra of logic and logical-probabilistic calculus. Managing the quality of human life is represented by managing the processes of his treatment, training and decision making. Events in these processes and the corresponding logical variables relate to the behavior of a person, other persons and infrastructure. The processes of the quality of human life are modeled, analyzed and managed with the participation of the person himself. Scenarios and structural, logical and probabilistic models of managing the quality of human life are given. Special software for quality management is described. The relationship of human quality of life and the digital economy is examined. We consider the role of public opinion in the management of the “bottom” based on the synthesis of many studies on the management of the economics and the state. The bottom management is also feedback from the top management.


2019 ◽  
Vol 58 (2) ◽  
pp. 249-259
Author(s):  
Joseph Acquisto

This essay examines a polemic between two Baudelaire critics of the 1930s, Jean Cassou and Benjamin Fondane, which centered on the relationship of poetry to progressive politics and metaphysics. I argue that a return to Baudelaire's poetry can yield insight into what seems like an impasse in Cassou and Fondane. Baudelaire provides the possibility of realigning metaphysics and politics so that poetry has the potential to become the space in which we can begin to think the two of them together, as opposed to seeing them in unresolvable tension. Or rather, the tension that Baudelaire animates between the two allows us a new way of thinking about the role of esthetics in moments of political crisis. We can in some ways see Baudelaire as responding, avant la lettre, to two of his early twentieth-century readers who correctly perceived his work as the space that breathes a new urgency into the questions of how modern poetry relates to the world from which it springs and in which it intervenes.


Author(s):  
Pavel Agapov ◽  
Kirill Stepkin

The article considers the general theoretical foundations of the relationship of sectarianism and religious extremism in the Russian Federation. Practical examples of the role of destructive sects in modern religious extremism in the Russian Federation are given.


2020 ◽  
Vol 63 (4) ◽  
pp. 115-131
Author(s):  
Maria M. Kuznetsova

The article examines the philosophy of Henri Bergson and William James as independent doctrines aimed at rational comprehension of spiritual reality. The doctrines imply the paramount importance of consciousness, the need for continuous spiritual development, the expansion of experience and perception. The study highlights the fundamental role of spiritual energy for individual and universal evolution, which likens these doctrines to the ancient Eastern teaching as well as to Platonism in Western philosophy. The term “spiritual energy” is used by Bergson and James all the way through their creative career, and therefore this concept should considered in the examination of their solution to the most important philosophical and scientific issues, such as the relationship of matter and spirit, consciousness and brain, cognition, free will, etc. The “radical empiricism” of William James and the “creative evolution” of Henry Bergson should be viewed as conceptions that based on peacemaking goals, because they are aimed at reconciling faith and facts, science and religion through the organic synthesis of sensory and spiritual levels of experience. Although there is a number of modern scientific discoveries that were foreseen by philosophical ideas of Bergson and James, both philosophers advocate for the artificial limitation of the sphere of experimental methods in science. They call not to limit ourselves to the usual intellectual schemes of reality comprehension, but attempt to touch the “living” reality, which presupposes an increase in the intensity of attention and will, but finally brings us closer to freedom.


Sign in / Sign up

Export Citation Format

Share Document