Quantum key distributionQuantum key distribution (QKD) is a secure communication method that implements a cryptographic protocol involving components of quantum mechanics. It enables two parties to produce a shared random secret key known only to them, which then can be used to encrypt and decrypt messages. The process of quantum key distribution is not to be confused with quantum cryptography, as it is the best-known example of a quantum-cryptographic task.
Tax havenA tax haven is a term, sometimes used negatively and for political reasons, to describe a place with very low tax rates for non-domiciled investors, even if the official rates may be higher. In some older definitions, a tax haven also offers financial secrecy. However, while countries with high levels of secrecy but also high rates of taxation, most notably the United States and Germany in the Financial Secrecy Index ("FSI") rankings, can be featured in some tax haven lists, they are often omitted from lists for political reasons or through lack of subject matter knowledge.
Noisy-channel coding theoremIn information theory, the noisy-channel coding theorem (sometimes Shannon's theorem or Shannon's limit), establishes that for any given degree of noise contamination of a communication channel, it is possible to communicate discrete data (digital information) nearly error-free up to a computable maximum rate through the channel. This result was presented by Claude Shannon in 1948 and was based in part on earlier work and ideas of Harry Nyquist and Ralph Hartley.
Scheme (programming language)Scheme is a dialect of the Lisp family of programming languages. Scheme was created during the 1970s at the MIT Computer Science and Artificial Intelligence Laboratory (MIT AI Lab) and released by its developers, Guy L. Steele and Gerald Jay Sussman, via a series of memos now known as the Lambda Papers. It was the first dialect of Lisp to choose lexical scope and the first to require implementations to perform tail-call optimization, giving stronger support for functional programming and associated techniques such as recursive algorithms.
Infimum and supremumIn mathematics, the infimum (abbreviated inf; plural infima) of a subset of a partially ordered set is the greatest element in that is less than or equal to each element of if such an element exists. In other words, it is the greatest element of that is lower or equal to the lowest element of . Consequently, the term greatest lower bound (abbreviated as ) is also commonly used. The supremum (abbreviated sup; plural suprema) of a subset of a partially ordered set is the least element in that is greater than or equal to each element of if such an element exists.
Chicken (Scheme implementation)Chicken (stylized as CHICKEN) is a programming language, specifically a compiler and interpreter which implement a dialect of the programming language Scheme, and which compiles Scheme source code to standard C. It is mostly R5RS compliant and offers many extensions to the standard. The newer R7RS standard is supported through an extension library. Chicken is free and open-source software available under a BSD license. It is implemented mostly in Scheme, with some parts in C for performance or to make embedding into C programs easier.
Ireland as a tax havenIreland has been labelled as a tax haven or corporate tax haven in multiple financial reports, an allegation which the state has rejected in response. Ireland is on all academic "tax haven lists", including the , and tax NGOs. Ireland does not meet the 1998 OECD definition of a tax haven, but no OECD member, including Switzerland, ever met this definition; only Trinidad & Tobago met it in 2017. Similarly, no EU–28 country is amongst the 64 listed in the 2017 EU tax haven blacklist and greylist.
