Inverting Onto Functions and Polynomial Hierarchy

In this paper we construct an oracle under which the polynomial hierarchy is infinite but there are non-invertible polynomial time computable multivalued onto functions

The Random Oracle Methodology, Revisited

We take a critical look at the relationship between the security of cryptographic schemes in the Random Oracle Model, and the security of the schemes that result from implementing the random oracle by so called "cryptographic hash functions". The main result of this paper is a negative one: There exist signature and encryption schemes that are secure in the Random Oracle Model, but for which any implementation of the random oracle results in insecure schemes. In the process of devising the above schemes, we consider possible definitions for the notion of a "good implementation" of a random oracle, pointing out limitations and challenges.Comment: 31 page

Evaluating the Efficacy of Value-driven Methods: A Controlled Experiment

A value model is an abstract representation of an organization and is used for capturing and describing the rationale of how the organization creates, delivers, and captures business value. Value-driven development methods use the notion of “economic value exchange” to define more efficient business strategies and align Information Systems with the organization goals. However, current value-driven methods are complex and there is not enough empirical evidence about which of the existing methods is more effective under what circumstances. This paper addresses this issue by presenting a controlled experiment aimed at comparing the Dynamic Value Description (DVD) method, which is a recently defined cognitive early requirements approach, with the well-known e3value method, with respect to their effectiveness, efficiency, perceived ease of use, perceived usefulness and intention to use. The results show that DVD has proved to be a promising method for specifying business value

Strong Turing Degrees for Additive BSS RAM's

For the additive real BSS machines using only constants 0 and 1 and order tests we consider the corresponding Turing reducibility and characterize some semi-decidable decision problems over the reals. In order to refine, step-by-step, a linear hierarchy of Turing degrees with respect to this model, we define several halting problems for classes of additive machines with different abilities and construct further suitable decision problems. In the construction we use methods of the classical recursion theory as well as techniques for proving bounds resulting from algebraic properties. In this way we extend a known hierarchy of problems below the halting problem for the additive machines using only equality tests and we present a further subhierarchy of semi-decidable problems between the halting problems for the additive machines using only equality tests and using order tests, respectively

Efficiency Theory: a Unifying Theory for Information, Computation and Intelligence

The paper serves as the first contribution towards the development of the theory of efficiency: a unifying framework for the currently disjoint theories of information, complexity, communication and computation. Realizing the defining nature of the brute force approach in the fundamental concepts in all of the above mentioned fields, the paper suggests using efficiency or improvement over the brute force algorithm as a common unifying factor necessary for the creation of a unified theory of information manipulation. By defining such diverse terms as randomness, knowledge, intelligence and computability in terms of a common denominator we are able to bring together contributions from Shannon, Levin, Kolmogorov, Solomonoff, Chaitin, Yao and many others under a common umbrella of the efficiency theory. © Taru Publications

Efficiency Theory: a Unifying Theory for Information, Computation and Intelligence

The paper serves as the first contribution towards the development of the theory of efficiency: a unifying framework for the currently disjoint theories of information, complexity, communication and computation. Realizing the defining nature of the brute force approach in the fundamental concepts in all of the above mentioned fields, the paper suggests using efficiency or improvement over the brute force algorithm as a common unifying factor necessary for the creation of a unified theory of information manipulation. By defining such diverse terms as randomness, knowledge, intelligence and computability in terms of a common denominator we are able to bring together contributions from Shannon, Levin, Kolmogorov, Solomonoff, Chaitin, Yao and many others under a common umbrella of the efficiency theory

The random oracle methodology, revisited

We take a critical look at the relationship between the security of cryptographic schemes in the Random Oracle Model, and the security of the schemes that result from implementing the random oracle by so called “cryptographic hash functions”. The main result of this paper is a negative one: There exist signature and encryption schemes that are secure in the Random Oracle Model, but for which any implementation of the random oracle results in insecure schemes. In the process of devising the above schemes, we consider possible definitions for the notion of a “good implementation” of a random oracle, pointing out limitations and challengesAccepted manuscrip

Bot Contracts

In this Article, we explain why the transactions commonly known as “smart contracts” are better understood as “bot contracts.” Taking an interdisciplinary approach, we show why the “smart contracts” moniker is misdescriptive in two important ways. First, these transactions are automated, not smart. Second, they do not afford parties many enforcement rights and defenses that one expects from common law contractual relationships. To fully understand these transactions, it is important to appreciate how the term “smart contracts” differs from what the technology delivers. Our review of the technology explains that these transactions have tremendous practical utility in reducing risk and avoiding the uncertainty and expense of seeking judicial enforcement. However, the electronic processes that occur in this category are not smart in the sense of being thoughtful, creative, or even amenable to change. They are programmed to follow preset instructions and execute automatically. Once the conditions for performance under a smart contract occur, performance cannot be stopped. Because these transactions are automated, they lack features and defenses available to those who enter into typical contractual relationships. Common law contracts are sets of promises or obligations that may be enforced by a court. However, once a smart contract is set in motion, no person or court can reverse the transaction. In this way, smart contracts differ fundamentally from traditional contracts because they leave no room for judicial intervention. By design, they evade the risk of what a court may do in fashioning a remedy. Courts have no power to set the transaction aside if it was induced by fraud or if another common law defense would, under other circumstances, render the transaction void or voidable. Although the term “smart contract” appears to have taken hold, we propose that these transactions are better thought of as “bot” or “automated” agreements. Reframing these transactions in this way would reset expectations in line with what the technology can deliver. Adopting this more encompassing terminology will send a strong informational signal that avoids misrepresenting the abilities of these agreements by more accurately communicating that they execute automatically and eliminate both the risks and benefits that accompany traditional common law contracts