We present a reformulation of loop quantum gravity with a cosmological constant and no matter as a Fermi-liquid theory. When the topological sector is deformed and large gauge symmetry is broken, we show that the Chern–Simons state reduces to Jacobson’s degenerate sector describing 1+1 dimensional propagating fermions with nonlocal interactions. The Hamiltonian admits a dual description which we realize in the simple BCS model of superconductivity. On one hand, Cooper pairs are interpreted as wormhole correlations at the de Sitter (...) horizon; their number yields the de Sitter entropy. On the other hand, BCS is mapped into a deformed conformal field theory reproducing the structure of quantum spin networks. When area measurements are performed, Cooper-pair insertions are activated on those edges of the spin network intersecting the given area, thus providing a description of quantum measurements in terms of excitations of a Fermi sea to superconducting levels. The cosmological constant problem is naturally addressed as a nonperturbative mass-gap effect of the true Fermi-liquid vacuum. (shrink)

We are demonstrating that the Luttinger model with short range interaction can be treated as a type of Fermi liquid. In line with the main dogma of Landau’s theory one can define a fermion excitation renormalized by interaction and show that in terms of these fermions any excited state of the system is described by free particles. The fermions are a mixture of renormalized right and left electrons. The electric charge and chirality of the Landau quasi-particle is discussed.

L’esame di un passo della Vita di Platone laerziana (III 2) – e di luoghi paralleli riferibili alla medesima tradizione – permette di mettere a fuoco un motivo mitico cruciale nei racconti sulla concorrenza tra essere umano e divinità nel gamos con una mortale: il divieto, che il nume impone al ‘rivale’ di inferiore natura, di congiungersi con la donna che reca in grembo il suo seme, finché l’eroina non abbia portato a termine la gravidanza. Le storie di personaggi femminili (...) colpevoli di duplice gamos – prima con il dio e poi, a breve distanza di tempo, con il mortale – si focalizzano sulle conseguenze nefaste del secondo contaminante connubio: uno per tutti il caso di Coronide madre di Asclepio (e forse il motivo era associato anche ad altre note madri mitiche, come Arianna, Semele e Alcmena). In questi esempi, tuttavia, in genere non è esplicitato il tema della proibizione divina, come invece accade nel bios di Diogene Laerzio. Qui infatti Apollo, dopo aver concepito Platone con Perictione, appare ad Aristone per vietargli il rapporto sessuale con la parthenos. (shrink)

Observational indications combined with analyses of analogue and emergent gravity in condensed matter systems support the possibility that there might be two distinct energy scales related to quantum gravity: the scale that sets the onset of quantum gravitational effects $E_{\rm B}$ (related to the Planck scale) and the much higher scale $E_{\rm L}$ signalling the breaking of Lorentz symmetry. We suggest a natural interpretation for these two scales: $E_{\rm L}$ is the energy scale below which a special relativistic spacetime emerges, (...) $E_{\rm B}$ is the scale below which this spacetime geometry becomes curved. This implies that the first ‘quantum’ gravitational effect around $E_{\rm B}$ could simply be that gravity is progressively switched off, leaving an effective Minkowski quantum field theory up to much higher energies of the order of $E_{\rm L}$ . This scenario may have important consequences for gravitational collapse, inasmuch as it opens up new possibilities for the final state of stellar collapse other than an evaporating black hole. (shrink)

Spin-half fermions are considered to be limited in a spherical potential well with periodic boundary conditions. The whole system is treated like a relativistic Fermi Gas. Solving the corresponding Dirac equation, the density of states, the Fermi energy, the average energy, the density of states of nucleons and the total energy of the ground-state are obtained.

We give an account of the appearance and first developments of the statistical model of atoms proposed by Thomas and Fermi, focusing on the main results achieved by Fermi and his group in Rome. Particular attention is addressed to the unknown contribution to this subject by Majorana, anticipating some important results reached later by leading physicists.

Expert reasoning combines voluminous domain‐specific knowledge with more general factual and strategic knowledge. Whereas expert system builders have recognized the need for specificity and problem‐solving researchers the need for generality, few attempts have been made to develop expert reasoning engines combining different kinds of knowledge at different levels of generality. This paper reports on the FERMI project, a computer‐implemented expert reasoner in the natural sciences that encodes factual and strategic knowledge in separate semantic hierarchies. The principled decomposition of knowledge (...) according to type and level of specificity yields both power and cross‐doman generality, as demonstrated in FERMI's ability to apply the same principles of invariance and decomposition to solve problems in fluid statics, DC‐circuits, and centroid location. Hierarchical knowledge representation and problem‐solving principles are discussed, and illustrative problem‐solving traces are presented. (shrink)

Fermi-Dirac statistics are one of two kinds of statistics exhibited by !identical quantum particles, the other being !Bose-Einstein statistics. Such particles are called fermions and bosons respectively (the terminology is due to Dirac [1902-1984] [1]). In the light of the !spin-statistics theorem, and consistent with observation, fermions are invariably spinors (of half-integral spin), whilst bosons are invariably scalar or vector particles (of integral spin). See !spin.

We present a Gedankenexperiment that leads to a violation of detailed balance if quantum mechanical transition probabilities are treated in the usual way by applying Fermi’s “golden rule”. This Gedankenexperiment introduces a collection of two-level systems that absorb and emit radiation randomly through non-reciprocal coupling to a waveguide, as realized in specific chiral quantum optical systems. The non-reciprocal coupling is modeled by a hermitean Hamiltonian and is compatible with the time-reversal invariance of unitary quantum dynamics. Surprisingly, the combination of (...) non-reciprocity with probabilistic radiation processes entails negative entropy production. Although the considered system appears to fulfill all conditions for Markovian stochastic dynamics, such a dynamics violates the Clausius inequality, a formulation of the second law of thermodynamics. Several implications concerning the interpretation of the quantum mechanical formalism are discussed. (shrink)

We consider the quantum electrodynamic problem of the velocity of transmission of an excitation from one atom to another, which was posed by Fermi in 1932 and, in an improved version, by Ferretti in 1968. The problem is solved using Heisenberg operators. The transmission velocity is shown to exceed the light velocity. We argue that this acausal result is to be explained by the inadmissibly idealized description of the signal source used by Fermi and Ferretti.

The concept of liquid modernity proposed by Zygmunt Bauman suggests a rapidly changing order that undermines all notions of durability. It implies a sense of rootlessness to all forms of social construction. In the field of development, such a concept challenges the meaning of modernization as an effort to establish long lasting structures. By applying this concept to development, it is possible to address the nuances of social change in terms of the interplay between the solid and liquid aspects of (...) modernization. (shrink)

There is nothing new about evil; it has been with us since time immemorial. But there is something new about the kind of evil that characterizes our contemporary liquid-modern world. The evil that characterized earlier forms of solid modernity was concentrated in the hands of states claiming monopolies on the means of coercion and using the means at their disposal to pursue their ends ends that were at times horrifically brutal and barbaric. In our contemporary liquid-modern societies, by contrast, evil (...) has become altogether more pervasive and at the same time less visible. Liquid evil hides in the seams of the canvass woven daily by the liquid-modern mode of human interaction and commerce, conceals itself in the very tissue of human cohabitation and in the course of its routine and day-to-day reproduction. Evil lurks in the countless black holes of a thoroughly deregulated and privatized social space in which cutthroat competition and mutual estrangement have replaced cooperation and solidarity, while forceful individualization erodes the adhesive power of inter-human bonds. In its present form evil is hard to spot, unmask and resist. It seduces us by its ordinariness and then jumps out without warning, striking seemingly at random. The result is a social world that is comparable to a minefield: we know it is full of explosives and that explosions will happen sooner or later but we have no idea when and where they will occur. In this new book, the sequel to their acclaimed work Moral Blindness Zygmunt Bauman and Leonidas Donskis guide the reader through this new terrain in which evil has become both more ordinary and more insidious, threatening to strip humanity of its dreams, alternative projects and powers of dissent at the very time when they are needed most. (shrink)

Bauman offers an exposition of his ideas against the context of art and artistic practices. He draws links between his work on ‘liquid modernity’ and the practices of Gustav Metzger dating back to the 1960s. In particular he stresses how Metzger’s concept of ‘auto-destructive art’ anticipates his own argument on the ways in which contemporary consumerism demands constant novelty, and hence a relentless flow of waste and dissipation - ‘disposal is already contained in the original design’. He develops his insights (...) with reference to the work of Villeglé, Valdes and Braun-Vega who each exemplify key aspects of the liquid modern; creation and destruction, the hopeless and desperate battle for attention, the directionless march of time. It is a sequence of incessant new beginnings, but each new start also contains the seeds of its own destruction and disappearance. (shrink)

In this paper, the concept of liquidation from the chapter on Self-consciousness in Hegel’s Phenomenology of Spirit is reconstructed and then used to deconstruct the systematic transition from sculpture to painting in the passage on the “System of the individual arts” in G.W.F. Hegel’s Aesthetics: Lectures on Fine Art. The aim is to show that such a deconstructed version of Hegel’s art philosophy provides a valid conceptual framework for the analysis of modern, particularly postmodern and contemporary art, which results as (...) liquid or liquidated art. Damien Hirst’s For the Love of God is discussed as major evidence for the concomitant neo-Hegelian claim that modern art has discursive reflection as its necessary supplement. (shrink)

The Fermi energy at 0°K is evaluated for electrons confined to cubical and spherical rigid-walled boxes of equal volume, respectively, in the Sommerfeld approximation. Due primarily to large differences in single-particle degeneracies, Fermi energies compared for equal numbers of particles in these two configurations are found to be unequal. Approximate expressions of the Fermi energy in the large particle-number limit for the spherical case reveal that it agrees in form with the Fermi energy for the cubical (...) configuration. The finite cylindrical box is also examined and it is found that for fixed number of particles and fixed volume, the Fermi energy varies as the two characteristic lengths of the box are changed. Experimental corroboration of the theory is suggested through measurement of the work function for equal-volume micrometallic samples in the different geometries. (shrink)

The title of this paper is inspired by the book edited by Domenico Fiormonte entitled Canoni liquidi (Liquid Canons). Of course, the adjective “liquid” refers to Zygmunt Bauman’s term at which my critique is also indirectly aimed. The title of Fiormonte’s book seems to suggest equivalence between textual “mobility” and “liquidity.” Yet the “liquefying” of (literary) canons and the emergence of new intrinsically kinetic or fluid forms of mobile textuality requires a critical assessment that does not prematurely celebrate the funeral (...) of the text as we know it but pays close attention to what seems to be waiting for us beyond the text, as suggested in Francesco Fiorentino’s recent edited volume. This means paying attention to what in my recent book, Il futuro della letteratura (The Future of Literature), I call digital incunabula: objects/textual tools, devices programmed in a twofold, reciprocal sense, whose linguistic properties and rules interact and interfere with the algorithmic procedures of artificial languages. In this programmed and programmable interaction and intermediation one can perceive the horizon of incomprehensibility of posthuman language, providing a new aporetic dimension to Gadamer’s assertion that “the being that can be understood is language.“ This assertion is by now the most significant issue in the horizon of literary (digital) arts. (shrink)

Why would a country strongly influenced by Buddhism's reverence for life allow legalized, widely used abortion? Equally puzzling to many Westerners is the Japanese practice of mizuko rites, in which the parents of aborted fetuses pray for the well-being of these rejected "lives." In this provocative investigation, William LaFleur examines abortion as a window on the culture and ethics of Japan. At the same time he contributes to the Western debate on abortion, exploring how the Japanese resolve their conflicting emotions (...) privately and avoid the pro-life/pro-choice politics that sharply divide Americans on the issue. (shrink)

This paper comments on a recent article “Revolutionary poetry and liquid crystal chemistry: Herman Gorter, Ada Prins and the interface between literature and science” by Hub Zwart, in which the author explores the influence of the liquid crystal research of Ada Prins on the epic poem Pan written by her long-time lover Herman Gorter. The present paper reviews the basic science of liquid crystals and explains the connections between the work of Prins and its influence on the poem. Other examples (...) of the use of “liquid crystal” as a literary device are identified from renaissance poetry, and the uses of the metaphor in these poems are analysed from a scientific perspective. From these examples it is suggested that creative concepts from poetry may contain elements of substance that appear in hitherto unrecognised scientific realities. (shrink)

‘Thinking liquid thoughts’ is an essay aiming at the aggregation of ideas and concepts which emerge and float when enquiring if there are characteristics related with the research of fields that artists could explore as new poetic venues for further works. Nanosciences and nanotechnologies will affect almost all features of everybody’s lives in the near future. What are the issues, either desirable or undesirable, we should try to point to considering the specific view related with art, architecture and design. We (...) also have to ask, which are the skills and tools that artists, architects and designers will need for developing research and creating work in these new fields. Opening with the idea of thinking liquid thoughts the essay also speculates about the possibility of creating interactive responsive works of art, extremely sensitive, exploring poetic possibilities for the creation of material products aiming a bi-univocal relationship between the computer simulation and the material realm. There is also research related with educational games and the programming of poetic journeys using virtual reality technologies, pointing to the convergence of silicon with carbon, which will bring about deep implications in the mode of production of things, thoughts ands processes.modelling, animation and VRML, Java Script and Java 3D languages. (shrink)

Analyses of contemporary surveillance are considered in relation to the growing liquidity of contemporary social relations. When state surveillance is revealed by Edward Snowden to depend on consumer data, this illustrates Bauman’s observations about today’s rapidly mobile and “extraterritorial” power. Such power is increasingly based on highly asymmetrical visibility of watcher and watched but paradoxically also depends on “panoptic selfie-surveillance” which complicates both analysis and ethics in significant ways. Strongly panoptic power, where it still exists, is largely at the margins, (...) in Bauman’s writing, as seen for instance his gesturing towards Loic Wacquant’s. Here, as in Didier Bigo’s “banopticon” the power is exclusionary rather than inclusionary — which was the form of the original panopticon design. But the soft forms of “selfie surveillance” also have panoptic dimensions that demand consideration. The ethical questions now foregrounded go far beyond questions of “privacy”, narrowly conceived, to issues of social inclusion and democratic participation. (shrink)

Over the last 30 years the effects of economic globalisation have transformed education and its relationship to work and everyday working lives. Market reform and the appropriation of ‘learning’ to fuel the knowledge economy produced a lifelong learning educational order, complemented by social inclusion to manage residual and resistant populations. In the process education was decentred, learning spaces were diversified within an education market that served the world of work. Educators were remaindered by a rising tide of coaches, counsellors, learning (...) managers and mentors who ‘facilitate’ rather than ‘teach’. In this groundbreaking book the author contextualises these changes as a way of re-reading our times and its educational effects. The chapters examine the interface of policy and practice and map the shifting relations between educational work and social organisations of learning by developing three key themes: _Liquid learning_: drawing on Bauman’s characterisation of ‘liquid modernity’, the concept of liquid leaning details the cultural conditions that confront educators and those who seek to use education as a social instrument to address economic, social, cultural, environmental and political development _Making spaces of orientation_: designing and realising strategies to address the challenges of "liquid modernity" _Educational work_: considering the specialist expertise that educators as an occupational group bring to the challenges of liquid learning. The case examples that make up the main body of this book show how spaces of orientation are made and how they can be designed to support learning for living in interdependence. Each of these cases is informed by substantial empirical research and fine-grained analyses are used to define the nature of educational work, the resources that are mobilised in constructing contexts for learning, and its contribution to the art of politics that makes spaces of orientation. As the author demonstrates, educators have expertise that is critical in the contemporary globalised world and its politics. (shrink)

It is common for social theorists to utilize the metaphors of ‘flow’, ‘fluidity’, and ‘liquidity’ in order to substantiate the ways in which speed and mobility form the basis for a new kind of information or network society. Yet rarely have these concepts been sufficiently theorized in order to establish their relevance or appropriateness. This article contends that the notion of flow as utilized in social theory is profoundly metaphysical in nature, and needs to be judged as such. Beginning with (...) a discussion of the accelerating timescape that characterizes the network society, it will then move on to examine three main issues with this ‘metaphysics of flux’. First, that the concept of flows unjustly privileges the process of becoming and, as a result, is unable to account for the materiality, substantiality, and agency of the objects being mobilized, and the contingency of their mediation. Second, that it posits the accelerating tendencies of capital as an ontological inevitability, thus discounting resistance to such forces. Finally, that it ignores the human faculty for reason and speculative thought in developing alternative means of political praxis. The solution, it will be argued, is not to abandon metaphysical accounts of the network society, but rather to challenge those accounts that, in exhibiting a crude empiricism, work to justify the status quo. (shrink)

Résumé Les soulèvements d’étudiants canadiens ne se contentent pas d’occuper les rues. Ils stimulent aussi l’émergence de modèles alternatifs de démocratie, comme la « démocratie liquide ». Celle-ci consiste à recourir régulièrement à des consultations populaires (sous forme de référendums, par exemple) sur des enjeux majeurs, avec la possibilité de transférer son vote à quelqu’un d’autre. De quoi raviver nos institutions sclérosées?

After having promoted and then tacitly abandoned the rhetoric of postmodernism, Zygmunt Bauman settled on the metaphor of a modernity that was growing more ‘liquid’ and ‘lighter’ than before. This essay explores the strengths and weaknesses of these metaphors, and attempts to contextualize Bauman’s insights in what has been called by the historian Yuri Slezkine the ‘Mercurian’ culture of diasporic Jewish life.