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Those with better reputations often obtain more resources than those with poorer reputations. Consequently, gossip might be an evolved strategy to compete for valuable and scarce material and social resources. Influenced by models of non-human primate competition, we test the hypotheses that gossip: (i) targets aspects of reputation relevant to the domain in which the competition is occurring, (ii) increases when contested resources are more valuable, and (iii) increases when resources are scarcer. We then test hypotheses derived from informational warfare theory, which proposes that coalitions strategically collect, analyse and disseminate gossip. Specifically, we test whether: (iv) coalitions deter negative gossip, and (v) whether they increase expectations of reputational harm to competitors. Using experimental methods in a Mechanical Turk sample ( n = 600), and survey and ego network analysis methods in a sample of California sorority women ( n = 74), we found that gossip content is specific to the context of the competition; that more valuable and scarcer resources cause gossip, particularly negative gossip, to intensify; and that allies deter negative gossip and increase expectations of reputational harm to an adversary. These results support social competition theories of gossip. This article is part of the theme issue 'The language of cooperation: reputation and honest signalling'.

Names for colors vary widely across languages, but color categories are remarkably consistent. Shared mechanisms of color perception help explain consistent partitions of visible light into discrete color vocabularies. But the mappings from colors to words are not identical across languages, which may reflect communicative needs-how often speakers must refer to objects of different color. Here we quantify the communicative needs of colors in 130 different languages by developing an inference algorithm for this problem. We find that communicative needs are not uniform: Some regions of color space exhibit 30-fold greater demand for communication than other regions. The regions of greatest demand correlate with the colors of salient objects, including ripe fruits in primate diets. Our analysis also reveals a hidden diversity in the communicative needs of colors across different languages, which is partly explained by differences in geographic location and the local biogeography of linguistic communities. Accounting for language-specific, nonuniform communicative needs improves predictions for how a language maps colors to words, and how these mappings vary across languages. Our account closes an important gap in the compression theory of color naming, while opening directions to study cross-cultural variation in the need to communicate different colors and its impact on the cultural evolution of color categories., Competing Interests: The authors declare no competing interest., (Copyright © 2021 the Author(s). Published by PNAS.)

Since its inception, Shannon's information theory has attracted interest for the study of language and music. Recently, a wide range of converging studies have shown how efficient communication pervades language, from phonetics to syntax. Efficient principles imply that more resources should be assigned to highly informative items. For instance, average information content was shown to be a better predictor of word length than frequency, revisiting the famous Zipf's law. However, in spite of the success of the efficient communication framework in the study of language and speech, very little work has investigated its relevance in the analysis of music. Here, we examine the organization of harmonic information in two large corpora of Western music, one made of MIDI files directly sequenced from scores, and the other made of MIDI recordings of live performances of highly skilled piano players. We show that there is a clear positive relationship between (contextual) information content of harmonic sequences and two essential musical properties, namely duration and loudness: the more unexpected a harmonic event is, the longer and the louder it is., (© 2020 Cognitive Science Society, Inc.)

Organisms have evolved sensory mechanisms to extract pertinent information from their environment, enabling them to assess their situation and act accordingly. For social organisms travelling in groups, like the fish in a school or the birds in a flock, sharing information can further improve their situational awareness and reaction times. Data on the benefits and costs of social coordination, however, have largely allowed our understanding of why collective behaviours have evolved to outpace our mechanistic knowledge of how they arise. Recent studies have begun to correct this imbalance through fine-scale analyses of group movement data. One approach that has received renewed attention is the use of information theoretic (IT) tools like mutual information , transfer entropy and causation entropy , which can help identify causal interactions in the type of complex, dynamical patterns often on display when organisms act collectively. Yet, there is a communications gap between studies focused on the ecological constraints and solutions of collective action with those demonstrating the promise of IT tools in this arena. We attempt to bridge this divide through a series of ecologically motivated examples designed to illustrate the benefits and challenges of using IT tools to extract deeper insights into the interaction patterns governing group-level dynamics. We summarize some of the approaches taken thus far to circumvent existing challenges in this area and we conclude with an optimistic, yet cautionary perspective.

The acceptability of sentences in natural language is constrained not only grammaticality, but also by the relationship between what is being conveyed and such factors as context and the beliefs of interlocutors. In many languages the critical element in a sentence (its focus) must be given grammatical prominence. There are different accounts of the nature of focus marking. Some researchers treat it as the grammatical realization of a potentially arbitrary feature of universal grammar and do not provide an explicit account of its origins; others have argued, however, that focus marking is a (grammaticalized) functional solution to the problem of efficiently transmitting information via a noisy channel. By adding redundancy to highlight critical elements in particular, focus protects key parts of the message from noise. If this information-theoretic account is true, then we should expect focus-like behavior to emerge even in non-linguistic communication systems given sufficient noise and pressures for efficiency. We tested this in an experiment in which participants played a simple communication game in which they had to click cells on a grid to communicate one of two line figures drawn across the grid. We manipulated the noise, available time, and required effort, and measured patterns of redundancy. Because the lines in many cases overlapped, meaning that only some parts of each line could be used to distinguish it from the other, we were able to compare the extent to which effort was expended on adding redundancy to critical (non-overlapping) and non-critical (overlapping) parts of the message. The results supported the information-theoretic account of focus and shed light on the emergence of information structure in language., (© 2019 Cognitive Science Society, Inc.)

It has recently become possible to study the dynamics of information diffusion in techno-social systems at scale, due to the emergence of online platforms, such as Twitter, with millions of users. One question that systematically recurs is whether information spreads according to simple or complex dynamics: does each exposure to a piece of information have an independent probability of a user adopting it (simple contagion), or does this probability depend instead on the number of sources of exposure, increasing above some threshold (complex contagion)? Most studies to date are observational and, therefore, unable to disentangle the effects of confounding factors such as social reinforcement, homophily, limited attention, or network community structure. Here we describe a novel controlled experiment that we performed on Twitter using 'social bots' deployed to carry out coordinated attempts at spreading information. We propose two Bayesian statistical models describing simple and complex contagion dynamics, and test the competing hypotheses. We provide experimental evidence that the complex contagion model describes the observed information diffusion behavior more accurately than simple contagion. Future applications of our results include more effective defenses against malicious propaganda campaigns on social media, improved marketing and advertisement strategies, and design of effective network intervention techniques.

We propose a model that explains the reliable emergence of power laws (e.g., Zipf's law) during the development of different human languages. The model incorporates the principle of least effort in communications, minimizing a combination of the information-theoretic communication inefficiency and direct signal cost. We prove a general relationship, for all optimal languages, between the signal cost distribution and the resulting distribution of signals. Zipf's law then emerges for logarithmic signal cost distributions, which is the cost distribution expected for words constructed from letters or phonemes.

Background: Explaining how the brain processing is so fast remains an open problem (van Hemmen JL, Sejnowski T., 2004). Thus, the analysis of neural transmission (Shannon CE, Weaver W., 1963) processes basically focuses on searching for effective encoding and decoding schemes. According to the Shannon fundamental theorem, mutual information plays a crucial role in characterizing the efficiency of communication channels. It is well known that this efficiency is determined by the channel capacity that is already the maximal mutual information between input and output signals. On the other hand, intuitively speaking, when input and output signals are more correlated, the transmission should be more efficient. A natural question arises about the relation between mutual information and correlation. We analyze the relation between these quantities using the binary representation of signals, which is the most common approach taken in studying neuronal processes of the brain., Results: We present binary communication channels for which mutual information and correlation coefficients behave differently both quantitatively and qualitatively. Despite this difference in behavior, we show that the noncorrelation of binary signals implies their independence, in contrast to the case for general types of signals., Conclusions: Our research shows that the mutual information cannot be replaced by sheer correlations. Our results indicate that neuronal encoding has more complicated nature which cannot be captured by straightforward correlations between input and output signals once the mutual information takes into account the structure and patterns of the signals.

Social animals may share information to obtain a more complete and accurate picture of their surroundings. However, physical constraints on communication limit the flow of information between interacting individuals in a way that can cause an accumulation of errors and deteriorated collective behaviors. Here, we theoretically study a general model of information sharing within animal groups. We take an algorithmic perspective to identify efficient communication schemes that are, nevertheless, economic in terms of communication, memory and individual internal computation. We present a simple and natural algorithm in which each agent compresses all information it has gathered into a single parameter that represents its confidence in its behavior. Confidence is communicated between agents by means of active signaling. We motivate this model by novel and existing empirical evidences for confidence sharing in animal groups. We rigorously show that this algorithm competes extremely well with the best possible algorithm that operates without any computational constraints. We also show that this algorithm is minimal, in the sense that further reduction in communication may significantly reduce performances. Our proofs rely on the Cramér-Rao bound and on our definition of a Fisher Channel Capacity. We use these concepts to quantify information flows within the group which are then used to obtain lower bounds on collective performance. The abstract nature of our model makes it rigorously solvable and its conclusions highly general. Indeed, our results suggest confidence sharing as a central notion in the context of animal communication.

Objective: To develop a model for Bayesian communication to enable readers to make reported data more relevant by including their prior knowledge and values., Background: To change their practice, clinicians need good evidence, yet they also need to make new technology applicable to their local knowledge and circumstances. Availability of the Web has the potential for greatly affecting the scientific communication process between research and clinician. Going beyond format changes and hyperlinking, Bayesian communication enables readers to make reported data more relevant by including their prior knowledge and values. This paper addresses the needs and implications for Bayesian communication. FORMULATION: Literature review and development of specifications from readers', authors', publishers', and computers' perspectives consistent with formal requirements for Bayesian reasoning., Results: Seventeen specifications were developed, which included eight for readers (express prior knowledge, view effect size and variability, express threshold, make inferences, view explanation, evaluate study and statistical quality, synthesize multiple studies, and view prior beliefs of the community), three for authors (protect the author's investment, publish enough information, make authoring easy), three for publishers (limit liability, scale up, and establish a business model), and two for computers (incorporate into reading process, use familiar interface metaphors). A sample client-only prototype is available at http://omie.med.jhmi.edu/bayes., Conclusion: Bayesian communication has formal justification consistent with the needs of readers and can best be implemented in an online environment. Much research must be done to establish whether the formalism and the reality of readers' needs can meet.

While largely ignored in informatics thinking, the clinical communication space accounts for the major part of the information flow in health care. Growing evidence indicates that errors in communication give rise to substantial clinical morbidity and mortality. This paper explores the implications of acknowledging the primacy of the communication space in informatics and explores some solutions to communication difficulties. It also examines whether understanding the dynamics of communication between human beings can also improve the way we design information systems in health care. Using the concept of common ground in conversation, proposals are suggested for modeling the common ground between a system and human users. Such models provide insights into when communication or computational systems are better suited to solving information problems.

Considering communication as an organizational task, this article suggests three variables (availability, uniformity, and independence) that characterize the information task at the work unit level and explicates their dependence on strategic choices by work units. Three sets of propositions are developed relating information task characteristics to: (a) organizational task variables; (b) the organization's communication structure; (c) power and influence in the organization. Implications of the framework are considered.

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Colour naming across languages has traditionally been held to reflect the structure of colour perception. At the same time, it has often, and increasingly, been suggested that colour naming may be shaped by patterns of communicative need. However, much remains unknown about the factors involved in communicative need, how need interacts with perception, and how this interaction may shape colour naming. Here, we engage these open questions by building on general information-theoretic principles. We present a systematic evaluation of several factors that may reflect need, and that have been proposed in the literature: capacity constraints, linguistic usage, and the visual environment. Our analysis suggests that communicative need in colour naming is reflected more directly by capacity constraints and linguistic usage than it is by the statistics of the visual environment.

Languages vary in their number of color terms. A widely accepted theory proposes that languages evolve, acquiring color terms in a stereotyped sequence. This theory, by Berlin and Kay (BK), is supported by analyzing best exemplars ("focal colors") of basic color terms in the World Color Survey (WCS) of 110 languages. But the instructions of the WCS were complex and the color chips confounded hue and saturation, which likely impacted focal-color selection. In addition, it is now known that even so-called early-stage languages nonetheless have a complete representation of color distributed across the population. These facts undermine the BK theory. Here we revisit the evolution of color terms using original color-naming data obtained with simple instructions in Tsimane', an Amazonian culture that has limited contact with industrialized society. We also collected data in Bolivian-Spanish speakers and English speakers. We discovered that information theory analysis of color-naming data was not influenced by color-chip saturation, which motivated a new analysis of the WCS data. Embedded within a universal pattern in which warm colors (reds, oranges) are always communicated more efficiently than cool colors (blues, greens), as languages increase in overall communicative efficiency about color, some colors undergo greater increases in communication efficiency compared to others. Communication efficiency increases first for yellow, then brown, then purple. The present analyses and results provide a new framework for understanding the evolution of color terms: what varies among cultures is not whether colors are seen differently, but the extent to which color is useful.

Gibson et al. () argued that color naming is shaped by patterns of communicative need. In support of this claim, they showed that color naming systems across languages support more precise communication about warm colors than cool colors, and that the objects we talk about tend to be warm-colored rather than cool-colored. Here, we present new analyses that alter this picture. We show that greater communicative precision for warm than for cool colors, and greater communicative need, may both be explained by perceptual structure. However, using an information-theoretic analysis, we also show that color naming across languages bears signs of communicative need beyond what would be predicted by perceptual structure alone. We conclude that color naming is shaped both by perceptual structure, as has traditionally been argued, and by patterns of communicative need, as argued by Gibson et al. -although for reasons other than those they advanced.

Several studies in philosophy, linguistics and neuroscience have tried to define the nature and functions of language. Cybernetics and the mathematical theory of communication have clarified the role and functions of signals, symbols and codes involved in the transmission of information. Linguistics has defined the main characteristics of verbal communication by analyzing the main tasks and levels of language. Paleoanthropology has explored the relationship between cognitive development and the origin of language in Homo sapiens. According to Daniel Dor, language represents the most important technological invention of human beings. Seemingly, the main function of language consists of its ability to allow the sharing of the mind's imaginative products. Following language's invention, human beings have developed multiple languages and cultures, which, on the one hand, have favored socialization within communities and, on the other hand, have led to an increase in aggression between different human groups. [ABSTRACT FROM AUTHOR]

We present an experimental study investigating the role ofinformation-theoretic factors in determining patterns of redun-dancy and focus in language and other communication sys-tems. Pairs of participants played a simple communicationgame using a non-linguistic visual medium to send messagesto each other. We manipulated noise, effort, and time pres-sures and measured message length, redundancy, and accuracy.Participants behaved as predicted based on an information-theoretic model, with message length and redundancy varyingaccording to circumstance, but accuracy remaining constant.

As state-of-the-art deep neural networks are being deployed at the core level of increasingly large numbers of AI-based products and services, the incentive for "copying them" (i.e., their intellectual property, manifested through the knowledge that is encapsulated in them) either by adversaries or commercial competitors is expected to considerably increase over time. The most efficient way to extract or steal knowledge from such networks is by querying them using a large dataset of random samples and recording their output, which is followed by the training of a student network, aiming to eventually mimic these outputs, without making any assumption about the original networks. The most effective way to protect against such a mimicking attack is to answer queries with the classification result only, omitting confidence values associated with the softmax layer. In this paper, we present a novel method for generating composite images for attacking a mentor neural network using a student model. Our method assumes no information regarding the mentor's training dataset, architecture, or weights. Furthermore, assuming no information regarding the mentor's softmax output values, our method successfully mimics the given neural network and is capable of stealing large portions (and sometimes all) of its encapsulated knowledge. Our student model achieved 99% relative accuracy to the protected mentor model on the Cifar-10 test set. In addition, we demonstrate that our student network (which copies the mentor) is impervious to watermarking protection methods and thus would evade being detected as a stolen model by existing dedicated techniques. Our results imply that all current neural networks are vulnerable to mimicking attacks, even if they do not divulge anything but the most basic required output, and that the student model that mimics them cannot be easily detected using currently available techniques. [ABSTRACT FROM AUTHOR]

We elaborate Alfred Schutz's theory of musical communication empirically. Our technique for analysing musical communication aligns Schutz's sociological theory with the mathematics of anticipatory systems. Music, we argue, can be considered as an anticipatory system that articulates through its diachronic unfolding, fundamental symmetries which can be traced back to its initial moments. Following Bohm and Dubois, we argue that these symmetries are present in fractal structures that gradually increase in definition as the music progresses. Critically, we focus on the role of redundancy in this process of providing increasing definition. By analysing the entropy of musical data, we show how graphs of relative entropies can be produced from which a fractal is constructed. In arguing that coherence in music can be established through the alignment of self‐similar patterns, the connection between Dubois's anticipatory systems and Schutz's characterization of the dimensions of musical communication shows how redundancy underlies musical coherence. [ABSTRACT FROM AUTHOR]

We introduce a theory of sequential causal inference in which learners in a chain estimate a structural model from their upstream "teacher" and then pass samples from the model to their downstream "student". It extends the population dynamics of genetic drift, recasting Kimura's selectively neutral theory as a special case of a generalized drift process using structured populations with memory. We examine the diffusion and fixation properties of several drift processes and propose applications to learning, inference, and evolution. We also demonstrate how the organization of drift process space controls fidelity, facilitates innovations, and leads to information loss in sequential learning with and without memory.

In this special issue devoted to speaking across communication subfields, we introduce a domain general explanatory framework that integrates biological explanation with communication science and organizes our field around a shared explanatory empirical model. Specifically, we draw on David Marr's classical framework, which subdivides the explanation of human behavior into three levels: computation (why), algorithm (what), and implementation (how). Prior theorizing and research in communication has primarily addressed Marr's computational level (why), but has less frequently investigated algorithmic (what) or implementation (how all communication phenomena emerge from and rely on biological processes) explanations. Here, we introduce Marr's framework and apply it to three research domains in communication science—audience research, persuasion, and social comparisons—to demonstrate what a unifying framework for explaining communication across the levels of why, what, and how can look like, and how Marr's framework speaks to and receives input from all subfields of communication inquiry. [ABSTRACT FROM AUTHOR]

This essay focuses on the manifestos and theoretical works of Concrete poets--primarily the German-language poets Max Bense and Eugen Gomringer, as well as the Noigandres group--examining their engagement with discourses of postwar modernity, including internationalism, design, and communication and information theory. While the movement's programmatic texts at times proved unpersuasive or inconsistent, they nonetheless demonstrated a readiness or even eagerness to cross boundaries--both national and disciplinary--and to seek inspiration from scientific and technical fields in an attempt to articulate a new poetics suited to the modern age. Rather than see the movement's manifestos and theoretical statements as hubristic promises that its poetry could never keep, this essay proposes that we see the poems and the programmatic texts as two parts of the same project, which claimed a place for poetry in a technologically saturated age. [ABSTRACT FROM AUTHOR]

The signal propagation and logical operations performed by the electrostatic interaction between the nanodots belonging to the quantum cellular automata (QCA) cells of different polarizations are influenced by the environmental noise like temperature fluctuations. The effect of thermal randomness on the computational fidelity of QCA-based 4-bit binary-to-Gray and binary-to-excess-3 code converters is studied in this article. The fidelity of computation of these digital circuits in the presence of noise is calculated by applying Shannon's information-theoretic measures, and thus, the robustness of the quantum cellular automata circuits to thermal noise is estimated. Finally, the temperature range over which the semiconductor quantum cellular automata circuits yield reliable computation is indicated. The proposed converters have minimum number of clock zones and high device density. [ABSTRACT FROM AUTHOR]

There has been comparatively little attention for the fundamental ontology of communication in recent philosophy. Nevertheless, from classical metaphysical accounts of relationality and communal being to the analysis of intersubjectivity in phenomenology and to concrete existence as understood by process philosophy, the communicative structure of the act of being has been, if not explicitly then implicitly, a perennial component of metaphysical reflection. Communication theory can be conceived in such a way that it takes this ontological dimension into account. The ramifications of connecting being to communication in this way are explored in discussion with the conceptualizations of communication in integrationism and biosemiotics. An interpretation of Gabriel Marcel's existential analysis of "my life" is used to show what philosophy as communication theory (in the strong sense of the notion elaborated here) might look like. [ABSTRACT FROM AUTHOR]

Grounded on persuasive communications theory, the impact of source credibility and message variation on response behaviour towards a mail survey on a sample of the general public are examined. An experimental design comprising three levels (high, medium and low) of these variables is employed. Source credibility and the interaction of message variation (i.e. usefulness of the study) and source credibility have a significant impact on response rate. Overemphasising the usefulness of a study is found to be counterproductive. For sources that are arguably average or lower in credibility, a strongly worded message (in terms of usefulness) was less effective than more modest objectives. [ABSTRACT FROM AUTHOR]

Three experiments examine how prevention-focused and promotion-focused consumers evaluate the comparison brand and what information they anchor on in direct comparative ads framed positively or negatively. Negative (vs. positive) frames lead prevention-focused respondents to exhibit higher evaluations for the advertised brand and lower evaluations for the comparison brand. Under promotion focus, positive (vs. negative) frames lead to more favorable attitudes toward the advertised brand with no difference in attitudes for the comparison brand. Preference for consistency is posited as a possible process explanation. We also find an evaluation order effect: prevention-focused (promotion-focused) individuals evaluate the comparison (advertised) brand first. [ABSTRACT FROM AUTHOR]

We revisit the problem of conveying classical messages by transmitting quantum states, and derive new, optimal bounds on the number of quantum bits required for this task. Much of the previous work on this problem, and on other communication tasks in the setting of bounded error entanglement-assisted communication, is based on sophisticated information theoretic arguments. Our results are derived from first principles, using a simple linear algebraic technique. A direct consequence is a tight lower bound for the Inner Product function that has found applications to privacy amplification in quantum key distribution protocols. [ABSTRACT FROM AUTHOR]

Convergence (i.e., mutual understanding) between an organization's CEO and CIO is critical to its efforts to successfully exploit information technology. Communication theory predicts that greater communication frequency and channel richness lead to more such convergence. A postal survey of 202 pairs of CEOs and CIOs investigated the effect of communication frequency and channel richness on CEO/ CIO convergence, as well as the effect of convergence on the financial contribution of information systems (IS) to the organization. Convergence was operationalized in terms of the current and future roles of information technology (IT) as defined by the strategic grid. Rigorous validation confirmed the current role as composed of one factor and the future role as composed of three factors (i.e., managerial support, differentiation, and enhancement). More frequent communication predicted convergence about the current role, differentiation future role, and enhancement future role. The use of richer channels predicted convergence about the differentiation future role. Convergence about the current role predicted IS financial contribution. From a research perspective, the study extended theory about communication frequency, media richness, convergence, and the role of IT in organizations. From a managerial perspective, it provided direction for CEOs and CIOs interested in increasing their mutual understanding of the role of IT. [ABSTRACT FROM AUTHOR]

Communication signals often comprise an array of colours, lines, spots, notes or odours that are arranged in complex patterns, melodies or blends. Receiver perception is assumed to influence preference and thus the evolution of signal design, but evolutionary biologists still struggle to understand how perception, preference and signal design are mechanistically linked. In parallel, the field of empirical aesthetics aims to understand why people like some designs more than others. The model of processing bias discussed here is rooted in empirical aesthetics, which posits that preferences are influenced by the emotional system as itmonitors the dynamics of information processing and that attractive signals have effective designs thatmaximize information transmission, efficient designs that allow information processing at lowmetabolic cost, or both. We refer to the causal link between preference and the emotionally rewarding experience of effective and efficient information processing as the processing bias, and we apply it to the evolutionary model of sensory drive. A sensory drive model that incorporates processing bias hypothesizes a causal chain of relationships between the environment, perception, pleasure, preference and ultimately the evolution of signal design, both simple and complex. [ABSTRACT FROM AUTHOR]

A central question in the classical information theory is that of source compression, which is the task where Alice receives a sample from a known probability distribution and needs to transmit it to the receiver Bob with small error. This problem has a one-shot solution due to Huffman, in which the messages are of variable length and the expected length of the messages matches the asymptotic and independent identically distributed (i.i.d.) compression rate of the Shannon entropy of the source. In this paper, we consider a quantum extension of above task, where Alice receives a sample from a known probability distribution and needs to transmit a part of a pure quantum state (that is associated with the sample) to Bob. We allow entanglement assistance in the protocol, so that the communication is possible through classical messages, for example using quantum teleportation. The classical messages can have a variable length, and the goal is to minimize their expected length. We provide a characterization of the expected communication cost of this task, by giving a lower bound that is near optimal up to some additive factors. A special case of above task, and the quantum analogue of the source compression problem, is when Alice needs to transmit the whole of her pure quantum state. Here, we show that there is no one-shot interactive scheme which matches the asymptotic and i.i.d. compression rate of the von Neumann entropy of the average quantum state. This is a relatively rare case in the quantum information theory where the cost of a quantum task is significantly different from its classical analogue. Furthermore, we also exhibit similar results for the fully quantum task of quantum state redistribution, employing some different techniques. We show implications for the one-shot version of the problem of quantum channel simulation. [ABSTRACT FROM AUTHOR]

The problem of providing privacy, in the private information retrieval (PIR) sense, to users requesting data from a distributed storage system (DSS), is considered. The DSS is coded by an $(n,k,d)$ maximum distance separable code to store the data reliably on unreliable storage nodes. Some of these nodes can be spies which report to a third party, such as an oppressive regime, which data is being requested by the user. An information theoretic PIR scheme ensures that a user can satisfy its request while revealing no information on which data is being requested to the nodes. A user can trivially achieve PIR by downloading all the data in the DSS. However, this is not a feasible solution due to its high communication cost. We construct PIR schemes with low download communication cost. When there is $b=1$ spy node in the DSS, in other words, no collusion between the nodes, we construct PIR schemes with download cost $\frac {1}{1-R}$ per unit of requested data ($R=k/n$ is the code rate), achieving the information theoretic limit for linear schemes. The proposed schemes are universal since they depend on the code rate, but not on the generator matrix of the code. Also, if $b\leq n-\delta k$ nodes collude, with $\delta =\lfloor {\frac {n-b}{k}}\rfloor $ , we construct linear PIR schemes with download cost $\frac {b+\delta k}{\delta }$. [ABSTRACT FROM AUTHOR]