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European Commission

The European Commission (EC) is the primary executive arm of the European Union (EU). It operates as a cabinet government, with 27 members of the Commission (directorial system, informally known as "Commissioners") headed by a President. It includes an administrative body of about 32,000 European civil servants. The commission is divided into departments known as Directorates-General (DGs) that can be likened to departments or ministries each headed by a Director-General who is responsible to a Commissioner.

There is one member per member state, but members are bound by their oath of office to represent the general interest of the EU as a whole rather than their home state. The Commission President (currently Ursula von der Leyen) is proposed by the European Council (the 27 heads of state/governments) and elected by the European Parliament. The Council of the European Union then nominates the other members of the Commission in agreement with the nominated President, and the 27 members as a team are then subject to a vote of approval by the European Parliament. The current Commission is the Von der Leyen Commission, which took office in December 2019, following the European Parliament elections in May of the same year.

History
The European Commission derives from one of the five key institutions created in the supranational European Community system, following the proposal of Robert Schuman, French Foreign Minister, on 9 May 1950. Originating in 1951 as the High Authority in the European Coal and Steel Community, the commission has undergone numerous changes in power and composition under various presidents, involving three Communities.

Establishment
The first Commission originated in 1951 as the nine-member "High Authority" under President Jean Monnet (see Monnet Authority). The High Authority was the supranational administrative executive of the new European Coal and Steel Community (ECSC). It took office first on 10 August 1952 in Luxembourg City. In 1958, the Treaties of Rome had established two new communities alongside the ECSC: the European Economic Community (EEC) and the European Atomic Energy Community (Euratom). However, their executives were called "Commissions" rather than "High Authorities". The reason for the change in name was the new relationship between the executives and the Council. Some states, such as France, expressed reservations over the power of the High Authority and wished to limit it by giving more power to the Council rather than the new executives.

Louis Armand led the first Commission of Euratom. Walter Hallstein led the first Commission of the EEC, holding the first formal meeting on 16 January 1958 at the Château of Val-Duchesse. It achieved agreement on a contentious cereal price accord, as well as making a positive impression upon third countries when it made its international debut at the Kennedy Round of General Agreement on Tariffs and Trade (GATT) negotiations. Hallstein notably began the consolidation of European law and started to have a notable impact on national legislation. Little heed was taken of his administration at first but, with help from the European Court of Justice, his Commission stamped its authority solidly enough to allow future Commissions to be taken more seriously. In 1965, however, accumulating differences between the French government of Charles de Gaulle and the other member states on various subjects (British entry, direct elections to Parliament, the Fouchet Plan and the budget) triggered the "empty chair" crisis, ostensibly over proposals for the Common Agricultural Policy. Although the institutional crisis was solved the following year, it cost Étienne Hirsch his presidency of Euratom and later Walter Hallstein the EEC presidency, despite his otherwise being viewed as the most 'dynamic' leader until Jacques Delors.

Early development
The three bodies, collectively named the European Executives, co-existed until 1 July 1967 when, under the Merger Treaty, they were combined into a single administration under President Jean Rey. Owing to the merger, the Rey Commission saw a temporary increase to 14 members—although subsequent Commissions were reduced back to nine, following the formula of one member for small states and two for larger states. The Rey Commission completed the Community's customs union in 1968 and campaigned for a more powerful, elected, European Parliament. Despite Rey being the first President of the combined communities, Hallstein is seen as the first President of the modern Commission.

The Malfatti and Mansholt Commissions followed with work on monetary co-operation and the first enlargement to the north in 1973. With that enlargement, the College of Commissioners membership increased to thirteen under the Ortoli Commission (the United Kingdom as a large member was granted two Commissioners), which dealt with the enlarged community during economic and international instability at that time. The external representation of the Community took a step forward when President Roy Jenkins, recruited to the presidency in January 1977 from his role as Home Secretary of the United Kingdom's Labour government, became the first President to attend a G8 summit on behalf of the Community. Following the Jenkins Commission, Gaston Thorn's Commission oversaw the Community's enlargement to the south, in addition to beginning work on the Single European Act.

Jacques Delors

The Commission headed by Jacques Delors was seen as giving the Community a sense of direction and dynamism. Delors and his College are also considered as the "founding fathers of the euro". The International Herald Tribune noted the work of Delors at the end of his second term in 1992: "Mr. Delors rescued the European Community from the doldrums. He arrived when Europessimism was at its worst. Although he was a little-known former French finance minister, he breathed life and hope into the EC and into the dispirited Brussels Commission. In his first term, from 1985 to 1988, he rallied Europe to the call of the single market, and when appointed to a second term he began urging Europeans toward the far more ambitious goals of economic, monetary, and political union".

Jacques Santer
The successor to Delors was Jacques Santer. As a result of a fraud and corruption scandal, the entire Santer Commission was forced by the Parliament to resign in 1999; a central role was played by Édith Cresson. These frauds were revealed by an internal auditor, Paul van Buitenen.

That was the first time a College of Commissioners had been forced to resign en masse, and represented a shift of power towards the Parliament. However, the Santer Commission did carry out work on the Treaty of Amsterdam and the euro. In response to the scandal, the European Anti-Fraud Office (OLAF) was created.

Romano Prodi
Following Santer, Romano Prodi took office. The Amsterdam Treaty had increased the commission's powers and Prodi was dubbed by the press as something akin to a Prime Minister. Powers were strengthened again; the Treaty of Nice, signed in 2001, gave the Presidents more power over the composition of the College of Commissioners.

José Manuel Barroso
José Manuel Barroso became president in 2004: the Parliament once again asserted itself in objecting to the proposed membership of the Barroso Commission. Owing to this opposition, Barroso was forced to reshuffle his College before taking office. The Barroso Commission was also the first full Commission since the enlargement in 2004 to 25 members; hence, the number of Commissioners at the end of the Prodi Commission had reached 30. As a result of the increase in the number of states, the Amsterdam Treaty triggered a reduction in the number of Commissioners to one per state, rather than two for the larger states.

Allegations of fraud and corruption were again raised in 2004 by former chief auditor Jules Muis. A Commission officer, Guido Strack, reported alleged fraud and abuses in his department in the years 2002–2004 to OLAF, and was fired as a result. In 2008, Paul van Buitenen (the former auditor known from the Santer Commission scandal) accused the European Anti-Fraud Office (OLAF) of a lack of independence and effectiveness.

Barroso's first Commission term expired on 31 October 2009. Under the Treaty of Nice, the first Commission to be appointed after the number of member states reached 27 would have to be reduced to "less than the number of Member States". The exact number of Commissioners was to be decided by a unanimous vote of the European Council, and membership would rotate equally between member states. Following the accession of Romania and Bulgaria in January 2007, this clause took effect for the next Commission. The Treaty of Lisbon, which came into force on 1 December 2009, mandated a reduction of the number of commissioners to two-thirds of member-states from 2014 unless the Council decided otherwise. Membership would rotate equally and no member state would have more than one Commissioner. However, the treaty was rejected by voters in Ireland in 2008 with one main concern being the loss of their Commissioner. Hence a guarantee given for a rerun of the vote was that the council would use its power to amend the number of Commissioners upwards. However, according to the treaties it still has to be fewer than the total number of members, thus it was proposed that the member state that does not get a Commissioner would get the post of High Representative – the so-called 26+1 formula. This guarantee (which may find its way into the next treaty amendment, probably in an accession treaty) contributed to the Irish approving the treaty in a second referendum in 2009.

Lisbon also combined the posts of European Commissioner for External Relations with the council's High Representative for the Common Foreign and Security Policy. This post, also a Vice-President of the Commission, would chair the Council of the European Union's foreign affairs meetings as well as the commission's external relations duties. The treaty further provides that the most recent European elections should be "taken into account" when appointing the President of the European Commission, and although they are still proposed by the European Council; the European Parliament "elects" candidates to the office, rather than "approves" them as under the Treaty of Nice.

The Barroso Commission is, in reaction to Euroscepticism, said to have toned down enforcement to increase integration.

Jean-Claude Juncker
In 2014, Jean-Claude Juncker became President of the European Commission.

Juncker appointed his previous campaign director and head of the transition team, Martin Selmayr, as his chief of cabinet. During the Juncker presidency Selmayr has been described as "the most powerful EU chief of staff ever."

Ursula von der Leyen

In 2019, Ursula von der Leyen was appointed as President of the European Commission. She submitted the guidelines of her policy to the European Parliament on 16 July 2019, following her confirmation. She had not been considered a likely candidate (in general, the elected candidate is determined, according to the results of the European election, as winner of the internal election into the dominant European party known as "spitzenkandidat"). While the European People's Party had won the European Parliament election, they had performed worse than expected and therefore nominated von der Leyen instead of Manfred Weber, their original candidate. On 9 September, the Council of the European Union declared a list of candidate-commissioners, which are sent to Brussels by the governments of each member state and which had to be officially approved by the parliament.

Powers and functions
The commission was set up from the start to act as an independent supranational authority separate from governments; it has been described as "the only body paid to think European". The members are proposed by their member state governments, one from each. However, they are bound to act independently – free from other influences such as those governments which appointed them. This is in contrast to the Council of the European Union, which represents governments, the European Parliament, which represents citizens, the Economic and Social Committee, which represents organised civil society, and the Committee of the Regions, which represents local and regional authorities.

Through Article 17 of the Treaty on European Union the commission has several responsibilities: to develop medium-term strategies; to draft legislation and arbitrate in the legislative process; to represent the EU in trade negotiations; to make rules and regulations, for example in competition policy; to draw up the budget of the European Union; and to scrutinise the implementation of the treaties and legislation. The rules of procedure of the European Commission set out the commission's operation and organisation.

Executive power
Before the Treaty of Lisbon came into force, the executive power of the EU was held by the council: it conferred on the Commission such powers for it to exercise. However, the council was allowed to withdraw these powers, exercise them directly, or impose conditions on their use. This aspect has been changed by the Treaty of Lisbon, after which the Commission exercises its powers just by virtue of the treaties. Powers are more restricted than most national executives, in part due to the commission's lack of power over areas like foreign policy – that power is held by the Council of the European Union and the European Council, which some analysts have described as another executive.

Considering that under the Treaty of Lisbon, the European Council has become a formal institution with the power of appointing the commission, it could be said that the two bodies hold the executive power of the EU (the European Council also holds individual national executive powers). However, it is the Commission that currently holds most of the executive power over the European Union.

Legislative initiative
The Commission differs from the other institutions in that it alone has legislative initiative in the EU. Only the commission can make formal proposals for legislation: they cannot originate in the legislative branches. Under the Treaty of Lisbon, no legislative act is allowed in the field of the Common Foreign and Security Policy. In the other fields, the Council and Parliament can request legislation; in most cases the Commission initiates on the basis of these proposals. This monopoly is designed to ensure coordinated and coherent drafting of EU law. This monopoly has been challenged by some who claim the Parliament should also have the right, with most national parliaments holding the right in some respects. However, the Council and Parliament may request the commission to draft legislation, though the Commission does have the power to refuse to do so as it did in 2008 over transnational collective conventions. Under the Lisbon Treaty, EU citizens are also able to request the commission to legislate in an area via a petition carrying one million signatures, but this is not binding.

The commission's powers in proposing law have usually centred on economic regulation. It has put forward a large number of regulations based on a "precautionary principle". This means that pre-emptive regulation takes place if there is a credible hazard to the environment or human health: for example on tackling climate change and restricting genetically modified organisms. The European Commission has committed EU member states to carbon neutrality by 2050. This is opposed to weighting regulations for their effect on the economy. Thus, the Commission often proposes stricter legislation than other countries. Owing to the size of the European market, this has made EU legislation an important influence in the global market. On February 23, 2022, the European Commission published the Corporate Sustainability Due Diligence Directive which establishes a framework of due diligence for companies to identify actual or potential risks and harm to human rights and the environment as well as establishing processes and standards to diminish these risks. The Directive is expected to be officially adopted in 2024 and then be incorporated into domestic laws within two years by all of the European Union member states.

Recently the commission has moved into creating European criminal law. In 2006, a toxic waste spill off the coast of Côte d'Ivoire, from a European ship, prompted the commission to look into legislation against toxic waste. at that time did not even have a crime against shipping toxic waste; this led the Commissioners Franco Frattini and Stavros Dimas to put forward the idea of "ecological crimes". Their right to propose criminal law was challenged in the European Court of Justice but upheld. the only other criminal law proposals which have been brought forward are on the intellectual property rights directive, and on an amendment to the 2002 counter-terrorism framework decision, outlawing terrorism‑related incitement, recruitment (especially via the internet) and training.

Enforcement
Once legislation is passed by the Council and Parliament, it is the commission's responsibility to ensure it is implemented. It does this through the member states or through its agencies. In adopting the necessary technical measures, the commission is assisted by committees made up of representatives of member states and of the public and private lobbies (a process known in jargon as "comitology"). Furthermore, the commission is responsible for the implementation of the EU budget, ensuring, along with the Court of Auditors, that EU funds are correctly spent.

In particular the commission has a duty to ensure the treaties and law are upheld, potentially by taking member states or other institutions to the Court of Justice in a dispute. In this role it is known informally as the "Guardian of the Treaties". Finally, the Commission provides some external representation for the Union, alongside the member states and the Common Foreign and Security Policy, representing the Union in bodies such as the World Trade Organization. It is also usual for the President to attend meetings of the G7.

College of Commissioners
The commission is composed of a "College of Commissioners" of members, including the President and vice-presidents. Even though each member is nominated on the basis of the suggestions made by the national governments, one per state, they do not represent their state in the commission. In practice, however, they do occasionally press for their national interest. Once proposed, the President delegates portfolios among each of the members. The power of a Commissioner largely depends upon their portfolio, and can vary over time. For example, the Education Commissioner has been growing in importance, in line with the rise in the importance of education and culture in European policy-making. Another example is the Competition Commissioner, who holds a highly visible position with global reach. Before the commission can assume office, the college as a whole must be approved by the Parliament. Commissioners are supported by their personal cabinet who give them political guidance, while the Civil Service (the DGs, see below) deal with technical preparation.

Appointment
The President of the Commission is first proposed by the European Council, following a Qualified Majority Vote (QMV), taking into account the latest parliamentary elections (any person from the largest party can be picked ); that candidate then faces a formal election in the European Parliament. Thus this serves as a form of indirect election. If the European Parliament fails to elect the candidate, the European Council shall propose another within one month.

Following the selection of the President, and the appointment of the High Representative by the European Council, each Commissioner is nominated by their member state (except for those states who provided the President and High Representative) in consultation with the Commission President, who is responsible for the allocation of portfolios. The President's proposed College of Commissioners is then subject to hearings at the European Parliament which will question them and then vote on their suitability as a whole. If the European Parliament submits a negative opinion of a candidate, the President must either reshuffle them or request a new candidate from the member state to avoid the college's outright rejection by the European Parliament. Once the college is approved by parliament, it is formally appointed following a QMV vote by the European Council.

Following the college's appointment, the President appoints a number of Vice-Presidents from among the commissioners. Vice-Presidents manage policy areas involving multiple Commissioners. One of these includes the High Representative, who is automatically one of the Vice-Presidents ex officio rather than by appointment and confirmation. Commonly referred to as the 'HR/VP' position, the High Representative also coordinates commissioners' activities involving the external relations and defence cooperation of the European Union. The von der Leyen Commission also created the position of more senior Executive Vice-Presidents, appointed from the three largest political groups in the European Parliament. Unlike the other vice-presidents, their mission is to manage the incumbent Commission's top priority policy areas, for which they receive additional support from a dedicated Directorate-General.

Dismissal
The European Parliament can dissolve the College of Commissioners as a whole following a vote of no-confidence, which requires a two-thirds vote.

Only the President can request the resignation of an individual Commissioner. However, individual Commissioners, by request of the council or Commission, can be compelled to retire on account of a breach of obligation(s) and if so ruled by the European Court of Justice (Art. 245 and 247, Treaty on the Functioning of the European Union).

Political styles
The Barroso Commission took office in late 2004 after being delayed by objections from the Parliament, which forced a reshuffle. In 2007 the Commission increased from 25 to 27 members with the accession of Romania and Bulgaria who each appointed their own Commissioners. With the increasing size of the commission, Barroso adopted a more presidential style of control over the college, which earned him some criticism.

However, under Barroso, the commission began to lose ground to the larger member states as countries such as France, the UK and Germany sought to sideline its role. This has increased with the creation of the President of the European Council under the Treaty of Lisbon. There has also been a greater degree of politicisation within the Commission.

Administration
The commission is divided into departments known as Directorates-General (DGs) that can be likened to departments or ministries. Each covers a specific policy area such as agriculture or justice and citizens' rights or internal services such as human resources and translation and is headed by a director-general who is responsible to a commissioner. A commissioner's portfolio can be supported by numerous DGs; they prepare proposals for them and if approved by a majority of commissioners proposals go forward to the Parliament and Council for consideration. The Commission's civil service is headed by a Secretary General. The position is currently held by Ilze Juhansone. The rules of procedure of the European Commission set out the commission's operation and organisation.

There has been criticism from a number of people that the highly fragmented DG structure wastes a considerable amount of time in turf wars as the different departments and Commissioners compete with each other. Furthermore, the DGs can exercise considerable control over a Commissioner with the Commissioner having little time to learn to assert control over their staff.

According to figures published by the commission, 23,803 persons were employed by the commission as officials and temporary agents in September 2012. In addition to these, 9230 "external staff" (e.g. Contractual agents, detached national experts, young experts, trainees etc.) were employed. The single largest DG is the Directorate-General for Translation, with a 2309-strong staff, while the largest group by nationality is Belgian (18.7%), probably due to a majority (17,664) of staff being based in the country.

Press

Communication with the press is handled by the Directorate-General Communication. The commission's chief spokesperson is Eric Mamer who holds the midday press briefings, commonly known as the "Midday Presser". It takes place every weekday in the commission's press room at the Berlaymont where journalists may ask questions to the Commission officials on any topic and legitimately expect to get an "on the record" answer for live TV. Such a situation is unique in the world.

As an integral part of the Directorate-General for Communication, the Spokesperson's Service, in coordination with the Executive Communication Adviser in the President's Cabinet, supports the President and Commissioners so that they can communicate effectively. On political communication matters, the chief spokesperson reports directly to the President of the European Commission.

It has been noted by one researcher that the press releases issued by the commission are uniquely political. A release often goes through several stages of drafting which emphasises the role of the commission and is used "for justifying the EU and the Commission" increasing their length and complexity. Where there are multiple departments involved a press release can also be a source of competition between areas of the Commission and Commissioners themselves. This also leads to an unusually high number of press releases, and is seen as a unique product of the EU's political set-up.

There is a larger press corps in Brussels than Washington, D.C.; in 2020, media outlets in every Union member-state had a Brussels correspondent. Although there has been a worldwide cut in journalists, the considerable press releases and operations such as Europe by Satellite and EuroparlTV leads many news organisations to believe they can cover the EU from these source and news agencies. The Commission shut down Presseurop on 20 December 2013, though the decision was criticised.

Legitimacy and criticism
As the commission is the executive branch, candidates are chosen individually by the national governments. Within the EU, the legitimacy of the commission is mainly drawn from the vote of approval that is required from the European Parliament, along with its power to dismiss the body. Eurosceptics have therefore raised the concern of the relatively low turnout (often less than 50%) in elections for the European Parliament since 1999. While that figure may be higher than that of some national elections, including the off-year elections of the United States Congress, the fact that there are no direct elections for the position of Commission President calls the position's legitimacy into question in the eyes of some Eurosceptics. The fact that the commission can directly decide (albeit with oversight from specially formed 'comitology committees') on the shape and character of implementing legislation further raises concerns about democratic legitimacy.

Even though democratic structures and methods are changing there is not such a mirror in creating a European civil society. The Treaty of Lisbon may go some way to resolving the perceived deficit in creating greater democratic controls on the commission, including enshrining the procedure of linking elections to the selection of the Commission president. Historically, the commission had indeed been seen as a technocratic expert body which, akin with institutions such as independent central banks, deals with technical areas of policy and therefore ought to be removed from party politics. From this viewpoint, electoral pressures would undermine the commission's role as an independent regulator. Defenders of the Commission point out that legislation must be approved by the Council in all areas (the ministers of member states) and the European Parliament in most areas before it can be adopted, thus the amount of legislation which is adopted in any one country without the approval of its government is limited.

In 2009 the European ombudsman published statistics of citizens' complaints against EU institutions, with most of them filed against the commission (66%) and concerning lack of transparency (36%). In 2010 the commission was sued for blocking access to documents on EU biofuel policy. This happened after media accused the Commission of blocking scientific evidence against biofuel subsidies. Lack of transparency, unclear lobbyist relations, conflicts of interests and excessive spending of the commission was highlighted in a number of reports by internal and independent auditing organisations. It has also been criticised on IT-related issues, particularly with regard to Microsoft. In September 2020, the European Commission put forward an Anti-Racism Action Plan to tackle the structural racism in the European Union, including measures to address the lack of racial diversity among the European decision makers in Brussels, as denounced by the #BrusselsSoWhite movement.

Anti-terrorism
The European Commission has an Action Plan to enhance preparedness against chemical, biological, radiological and nuclear (CBRN) security risks as part of its anti-terrorism package released in October 2017. In recent times Europe has seen an increased threat level of CBRN attacks. As such, the European Commission's preparedness plan is important, said Steven Neville Chatfield, a director for the Centre for Emergency Preparedness and Response in the United Kingdom's Health Protection Agency. For the first time, the European Commission proposed that medical preparedness for CBRN attack threats is a high priority. "The European Commission's (EC) Action Plan to enhance preparedness against CBRN security risks is part of its anti-terrorism package released in October 2017, a strategy aimed at better protecting the more than 511 million citizens across the 27 member states of the European Union (EU)."

COVID-19 response
The European Commission organized a video conference of world leaders on 4 May 2020 to raise funds for COVID-19 vaccine development. US$8 billion was raised.

The European Commission issued a new multi-year data plan in February 2020 pushing the digitalization of all aspects of EU society for the benefit of civic and economic growth.

The goal of this data strategy is to create a single market for data in which data flows across the EU and across sectors while maintaining full respect for privacy and data protection, where access rules are fair, and where the European economy benefits enormously as a global player as a result of the new data economy.

Location

The commission's political seat is in Brussels with the President's office and the commission's meeting room on the 13th floor of the Berlaymont building. The commission also operates out of numerous other buildings in Brussels and Luxembourg City. When the Parliament is meeting in Strasbourg, the Commissioners also meet there in the Winston Churchill building to attend the Parliament's debates. The Members of the Commission and their "cabinets" (immediate teams) are also based in the Berlaymont building in Brussels. Additionally, the European Commission has in-house scientific facilities that support it in: Ispra, Italy; Petten, Netherlands; Karlsruhe, Germany; Geel, Belgium and Seville, Spain. In Grange, County Meath, Ireland, a Commission site is hosting part of DG Santè.

title: European Commission


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Linear filter

Linear filters process time-varying input signals to produce output signals, subject to the constraint of linearity. In most cases these linear filters are also time invariant (or shift invariant) in which case they can be analyzed exactly using LTI ("linear time-invariant") system theory revealing their transfer functions in the frequency domain and their impulse responses in the time domain. Real-time implementations of such linear signal processing filters in the time domain are inevitably causal, an additional constraint on their transfer functions. An analog electronic circuit consisting only of linear components (resistors, capacitors, inductors, and linear amplifiers) will necessarily fall in this category, as will comparable mechanical systems or digital signal processing systems containing only linear elements. Since linear time-invariant filters can be completely characterized by their response to sinusoids of different frequencies (their frequency response), they are sometimes known as frequency filters.

Non real-time implementations of linear time-invariant filters need not be causal. Filters of more than one dimension are also used such as in image processing. The general concept of linear filtering also extends into other fields and technologies such as statistics, data analysis, and mechanical engineering.

Impulse response and transfer function
A linear time-invariant (LTI) filter can be uniquely specified by its impulse response h, and the output of any filter is mathematically expressed as the convolution of the input with that impulse response. The frequency response, given by the filter's transfer function $$H(\omega)$$, is an alternative characterization of the filter. Typical filter design goals are to realize a particular frequency response, that is, the magnitude of the transfer function $$|H(\omega)|$$; the importance of the phase of the transfer function varies according to the application, inasmuch as the shape of a waveform can be distorted to a greater or lesser extent in the process of achieving a desired (amplitude) response in the frequency domain. The frequency response may be tailored to, for instance, eliminate unwanted frequency components from an input signal, or to limit an amplifier to signals within a particular band of frequencies.

The impulse response h of a linear time-invariant causal filter specifies the output that the filter would produce if it were to receive an input consisting of a single impulse at time 0. An "impulse" in a continuous time filter means a Dirac delta function; in a discrete time filter the Kronecker delta function would apply. The impulse response completely characterizes the response of any such filter, inasmuch as any possible input signal can be expressed as a (possibly infinite) combination of weighted delta functions. Multiplying the impulse response shifted in time according to the arrival of each of these delta functions by the amplitude of each delta function, and summing these responses together (according to the superposition principle, applicable to all linear systems) yields the output waveform.

Mathematically this is described as the convolution of a time-varying input signal x(t) with the filter's impulse response h, defined as:

 * $$y(t) = \int_{0}^{T} x(t-\tau)\, h(\tau)\, d\tau$$ or
 * $$y_k = \sum_{i=0}^{N} x_{k-i}\, h_i $$.

The first form is the continuous-time form, which describes mechanical and analog electronic systems, for instance. The second equation is a discrete-time version used, for example, by digital filters implemented in software, so-called digital signal processing. The impulse response h completely characterizes any linear time-invariant (or shift-invariant in the discrete-time case) filter. The input x is said to be "convolved" with the impulse response h having a (possibly infinite) duration of time T (or of N sampling periods).

Filter design consists of finding a possible transfer function that can be implemented within certain practical constraints dictated by the technology or desired complexity of the system, followed by a practical design that realizes that transfer function using the chosen technology. The complexity of a filter may be specified according to the order of the filter.

Among the time-domain filters we here consider, there are two general classes of filter transfer functions that can approximate a desired frequency response. Very different mathematical treatments apply to the design of filters termed infinite impulse response (IIR) filters, characteristic of mechanical and analog electronics systems, and finite impulse response (FIR) filters, which can be implemented by discrete time systems such as computers (then termed digital signal processing).

Infinite impulse response filters
Consider a physical system that acts as a linear filter, such as a system of springs and masses, or an analog electronic circuit that includes capacitors and/or inductors (along with other linear components such as resistors and amplifiers). When such a system is subject to an impulse (or any signal of finite duration) it responds with an output waveform that lasts past the duration of the input, eventually decaying exponentially in one or another manner, but never completely settling to zero (mathematically speaking). Such a system is said to have an infinite impulse response (IIR). The convolution integral (or summation) above extends over all time: T (or N) must be set to infinity.

For instance, consider a damped harmonic oscillator such as a pendulum, or a resonant L-C tank circuit. If the pendulum has been at rest and we were to strike it with a hammer (the "impulse"), setting it in motion, it would swing back and forth ("resonate"), say, with an amplitude of 10 cm. After 10 minutes, say, the pendulum would still be swinging but the amplitude would have decreased to 5 cm, half of its original amplitude. After another 10 minutes its amplitude would be only 2.5 cm, then 1.25 cm, etc. However it would never come to a complete rest, and we therefore call that response to the impulse (striking it with a hammer) "infinite" in duration.

The complexity of such a system is specified by its order N. N is often a constraint on the design of a transfer function since it specifies the number of reactive components in an analog circuit; in a digital IIR filter the number of computations required is proportional to N.

Finite impulse response filters
A filter implemented in a computer program (or a so-called digital signal processor) is a discrete-time system; a different (but parallel) set of mathematical concepts defines the behavior of such systems. Although a digital filter can be an IIR filter if the algorithm implementing it includes feedback, it is also possible to easily implement a filter whose impulse truly goes to zero after N time steps; this is called a finite impulse response (FIR) filter.

For instance, suppose one has a filter that, when presented with an impulse in a time series:
 * 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 ...

outputs a series that responds to that impulse at time 0 until time 4, and has no further response, such as:
 * 0, 0, 0, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0.....

Although the impulse response has lasted 4 time steps after the input, starting at time 5 it has truly gone to zero. The extent of the impulse response is finite, and this would be classified as a fourth-order FIR filter. The convolution integral (or summation) above need only extend to the full duration of the impulse response T, or the order N in a discrete time filter.

Implementation issues
Classical analog filters are IIR filters, and classical filter theory centers on the determination of transfer functions given by low order rational functions, which can be synthesized using the same small number of reactive components. Using digital computers, on the other hand, both FIR and IIR filters are straightforward to implement in software.

A digital IIR filter can generally approximate a desired filter response using less computing power than a FIR filter, however this advantage is more often unneeded given the increasing power of digital processors. The ease of designing and characterizing FIR filters makes them preferable to the filter designer (programmer) when ample computing power is available. Another advantage of FIR filters is that their impulse response can be made symmetric, which implies a response in the frequency domain that has zero phase at all frequencies (not considering a finite delay), which is absolutely impossible with any IIR filter.

Frequency response
The frequency response or transfer function $$|H(\omega)|$$ of a filter can be obtained if the impulse response is known, or directly through analysis using Laplace transforms, or in discrete-time systems the Z-transform. The frequency response also includes the phase as a function of frequency, however in many cases the phase response is of little or no interest. FIR filters can be made to have zero phase, but with IIR filters that is generally impossible. With most IIR transfer functions there are related transfer functions having a frequency response with the same magnitude but a different phase; in most cases the so-called minimum phase transfer function is preferred.

Filters in the time domain are most often requested to follow a specified frequency response. Then, a mathematical procedure finds a filter transfer function that can be realized (within some constraints), and approximates the desired response to within some criterion. Common filter response specifications are described as follows:

 * A low-pass filter passes low frequencies while blocking higher frequencies.
 * A high-pass filter passes high frequencies.
 * A band-pass filter passes a band (range) of frequencies.
 * A band-stop filter passes high and low frequencies outside of a specified band.
 * A notch filter has a null response at a particular frequency. This function may be combined with one of the above responses.
 * An all-pass filter passes all frequencies equally well, but alters the phase relationship among them.
 * An equalization filter is not designed to fully pass or block any frequency, but instead to gradually vary the amplitude response as a function of frequency: filters used as pre-emphasis filters, equalizers, or tone controls are good examples.

FIR transfer functions
Meeting a frequency response requirement with an FIR filter uses relatively straightforward procedures. In the most basic form, the desired frequency response itself can be sampled with a resolution of $$\Delta f$$ and Fourier transformed to the time domain. This obtains the filter coefficients hi, which implements a zero phase FIR filter that matches the frequency response at the sampled frequencies used. To better match a desired response, $$\Delta f$$ must be reduced. However the duration of the filter's impulse response, and the number of terms that must be summed for each output value (according to the above discrete time convolution) is given by $$N=1/(\Delta f \, T)$$ where T is the sampling period of the discrete time system (N-1 is also termed the order of an FIR filter). Thus the complexity of a digital filter and the computing time involved, grows inversely with $$\Delta f$$, placing a higher cost on filter functions that better approximate the desired behavior. For the same reason, filter functions whose critical response is at lower frequencies (compared to the sampling frequency 1/T) require a higher order, more computationally intensive FIR filter. An IIR filter can thus be much more efficient in such cases.

Elsewhere the reader may find further discussion of design methods for practical FIR filter design.

IIR transfer functions
Since classical analog filters are IIR filters, there has been a long history of studying the range of possible transfer functions implementing various of the above desired filter responses in continuous time systems. Using transforms it is possible to convert these continuous time frequency responses to ones that are implemented in discrete time, for use in digital IIR filters. The complexity of any such filter is given by the order N, which describes the order of the rational function describing the frequency response. The order N is of particular importance in analog filters, because an Nth order electronic filter requires N reactive elements (capacitors and/or inductors) to implement. If a filter is implemented using, for instance, biquad stages using op-amps, N/2 stages are needed. In a digital implementation, the number of computations performed per sample is proportional to N. Thus the mathematical problem is to obtain the best approximation (in some sense) to the desired response using a smaller N, as we shall now illustrate.

Below are the frequency responses of several standard filter functions that approximate a desired response, optimized according to some criterion. These are all fifth-order low-pass filters, designed for a cutoff frequency of .5 in normalized units. Frequency responses are shown for the Butterworth, Chebyshev, inverse Chebyshev, and elliptic filters.

As is clear from the image, the elliptic filter is sharper than the others, but at the expense of ripples in both its passband and stopband. The Butterworth filter has the poorest transition but has a more even response, avoiding ripples in either the passband or stopband. A Bessel filter (not shown) has an even poorer transition in the frequency domain, but maintains the best phase fidelity of a waveform. Different applications emphasize different design requirements, leading to different choices among these (and other) optimizations, or requiring a filter of a higher order.

Example implementations
A popular circuit implementing a second order active R-C filter is the Sallen-Key design, whose schematic diagram is shown here. This topology can be adapted to produce low-pass, band-pass, and high pass filters.

An Nth order FIR filter can be implemented in a discrete time system using a computer program or specialized hardware in which the input signal is subject to N delay stages. The output of the filter is formed as the weighted sum of those delayed signals, as is depicted in the accompanying signal flow diagram. The response of the filter depends on the weighting coefficients denoted b0, b1, .... bN. For instance, if all of the coefficients were equal to unity, a so-called boxcar function, then it would implement a low-pass filter with a low frequency gain of N+1 and a frequency response given by the sinc function. Superior shapes for the frequency response can be obtained using coefficients derived from a more sophisticated design procedure.

Mathematics of filter design
LTI system theory describes linear time-invariant (LTI) filters of all types. LTI filters can be completely described by their frequency response and phase response, the specification of which uniquely defines their impulse response, and vice versa. From a mathematical viewpoint, continuous-time IIR LTI filters may be described in terms of linear differential equations, and their impulse responses considered as Green's functions of the equation. Continuous-time LTI filters may also be described in terms of the Laplace transform of their impulse response, which allows all of the characteristics of the filter to be analyzed by considering the pattern of zeros and poles of their Laplace transform in the complex plane. Similarly, discrete-time LTI filters may be analyzed via the Z-transform of their impulse response.

Before the advent of computer filter synthesis tools, graphical tools such as Bode plots and Nyquist plots were extensively used as design tools. Even today, they are invaluable tools to understanding filter behavior. Reference books had extensive plots of frequency response, phase response, group delay, and impulse response for various types of filters, of various orders. They also contained tables of values showing how to implement such filters as RLC ladders - very useful when amplifying elements were expensive compared to passive components. Such a ladder can also be designed to have minimal sensitivity to component variation a property hard to evaluate without computer tools.

Many different analog filter designs have been developed, each trying to optimise some feature of the system response. For practical filters, a custom design is sometimes desirable, that can offer the best tradeoff between different design criteria, which may include component count and cost, as well as filter response characteristics.

These descriptions refer to the mathematical properties of the filter (that is, the frequency and phase response). These can be implemented as analog circuits (for instance, using a Sallen Key filter topology, a type of active filter), or as algorithms in digital signal processing systems.

Digital filters are much more flexible to synthesize and use than analog filters, where the constraints of the design permits their use. Notably, there is no need to consider component tolerances, and very high Q levels may be obtained.

FIR digital filters may be implemented by the direct convolution of the desired impulse response with the input signal. They can easily be designed to give a matched filter for any arbitrary pulse shape.

IIR digital filters are often more difficult to design, due to problems including dynamic range issues, quantization noise and instability. Typically digital IIR filters are designed as a series of digital biquad filters.

All low-pass second-order continuous-time filters have a transfer function given by

 * $$H(s)=\frac{K \omega^{2}_{0}}{s^{2}+\frac{\omega_{0}}{Q}s+\omega^{2}_{0}}.$$

All band-pass second-order continuous-time filters have a transfer function given by

 * $$H(s)=\frac{K \frac{\omega_{0}}{Q}s}{s^{2}+\frac{\omega_{0}}{Q}s+\omega^{2}_{0}}.$$

where
 * K is the gain (low-pass DC gain, or band-pass mid-band gain) (K is 1 for passive filters)
 * Q is the Q factor
 * $$\omega_{0}$$ is the center frequency
 * $$s=\sigma+j\omega$$ is the complex frequency

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: Linear filter


text:
Ergative case

In grammar, the ergative case (abbreviated ) is the grammatical case that identifies a nominal phrase as the agent of a transitive verb in ergative–absolutive languages.

Characteristics
In such languages, the ergative case is typically marked (most salient), while the absolutive case is unmarked. Recent work in case theory has vigorously supported the idea that the ergative case identifies the agent (the intentful performer of an action) of a verb.

In Kalaallisut (Greenlandic) for example, the ergative case is used to mark subjects of transitive verbs and possessors of nouns. This syncretism with the genitive is commonly referred to as the relative case.

Nez Perce has a three-way nominal case system with both ergative (-nim) and accusative (-ne) plus an absolute (unmarked) case for intransitive subjects: hipáayna qíiwn ‘the old man arrived’; hipáayna wewúkiye ‘the elk arrived’; wewúkiyene péexne qíiwnim ‘the old man saw an elk’.

Sahaptin has an ergative noun case (with suffix -nɨm) that is limited to transitive constructions only when the direct object is 1st or 2nd person: iwapáatayaaš łmámanɨm ‘the old woman helped me’; paanáy iwapáataya łmáma ‘the old woman helped him/her’ (direct); páwapaataya łmámayin ‘the old woman helped him/her’ (inverse).

In languages with an optional ergative, the choice between marking the ergative case or not depends on semantic or pragmatics aspects such as marking focus on the argument.

Other languages that use the ergative case are Georgian, Chechen, and other Caucasian languages, Mayan languages, Mixe–Zoque languages, Wagiman and other Australian Aboriginal languages as well as Basque, Burushaski and Tibetan. Among all Indo-European languages, only Yaghnobi, Kurdish language varieties (including Kurmanji, Zazaki and Sorani) and Pashto from the Iranian languages and Hindi/Urdu, along with some other Indo-Aryan languages, are ergative.

The ergative case is also a feature of some constructed languages such as Na'vi, Ithkuil and Black Speech.

title: Ergative case


text:
Ewe

A ewe is a female sheep.

Ewe or EWE may also refer to:

Culture

 * Ewe people, an ethnic group in the Eastern parts of Ghana, Benin and Togo
 * Ewe language
 * Ewe music

Geography

 * Isle of Ewe, an island off the west coast of Scotland
 * Loch Ewe, a sea loch in Scotland
 * St Ewe, a village in Cornwall

People

 * David Ewe, New Zealand rugby player
 * Donna Ewe (born 1964), New Zealand rugby union player

Transportation

 * Eurowings Europe, an Austrian airline
 * Ewell East railway station in Surrey, England
 * Ewer Airport, in Indonesia

Other uses

 * Ecopath with Ecosim, an ecological computer modelling system for fisheries
 * EWE Baskets Oldenburg, a German basketball team
 * Large EWE Arena in Oldenburg, Germany
 * Small EWE Arena in Oldenburg, Germany

title: Ewe


text:
Essenes

The Essenes (Hebrew:, Isiyim; Greek: Ἐσσηνοί, Ἐσσαῖοι, or Ὀσσαῖοι, Essenoi, Essaioi, Ossaioi) or Essenians were a mystic Jewish sect during the Second Temple period that flourished from the 2nd century BCE to the 1st century CE.

The Essene movement likely originated as a distinct group among Jews during Jonathan Apphus' time, driven by disputes over Jewish law and the belief that Jonathan's high priesthood was illegitimate. Most scholars think the Essenes seceded from the Zadokite priests. They saw themselves as the genuine remnant of Israel, upholding the true covenant with God, and attributed their interpretation of the Torah to their early leader, the Teacher of Righteousness, possibly a legitimate high priest. Embracing a conservative approach to Jewish law, they observed a strict hierarchy favoring priests (the Sons of Zadok) over laypeople, emphasized ritual purity, and held a dualistic worldview.

According to Jewish writers Josephus and Philo, the Essenes numbered around four thousand, and resided in various settlements throughout Judaea. Conversely, Roman writer Pliny the Elder positioned them somewhere above Ein Gedi, on the west side of the Dead Sea. Pliny relates in a few lines that the Essenes possess no money, had existed for thousands of generations, and that their priestly class ("contemplatives") did not marry. Josephus gave a detailed account of the Essenes in The Jewish War (c. 75 CE), with a shorter description in Antiquities of the Jews (c. 94 CE) and The Life of Flavius Josephus (c. 97 CE). Claiming firsthand knowledge, he lists the Essenoi as one of the three sects of Jewish philosophy alongside the Pharisees and Sadducees. He relates the same information concerning piety, celibacy; the absence of personal property and of money; the belief in communality; and commitment to a strict observance of Sabbath. He further adds that the Essenes ritually immersed in water every morning (a practice similar to the use of the mikveh for daily immersion found among some contemporary Hasidim), ate together after prayer, devoted themselves to charity and benevolence, forbade the expression of anger, studied the books of the elders, preserved secrets, and were very mindful of the names of the angels kept in their sacred writings.

The Essenes have gained fame in modern times as a result of the discovery of an extensive group of religious documents known as the Dead Sea Scrolls, which are commonly believed to be the Essenes' library. The scrolls were found at Qumran, an archaeological site situated along the northwestern shore of the Dead Sea, believed to have been the dwelling place of an Essene community. These documents preserve multiple copies of parts of the Hebrew Bible along with deuterocanonical and sectarian manuscripts, including writings such as the Community Rule, the Damascus Document, and the War Scroll, which provide valuable insights into the communal life, ideology and theology of the Essenes.

According to the conventional view, the Essenes disappeared after the First Jewish–Roman War, which also witnessed the destruction of the settlement at Qumran. Scholars have noted the absence of direct sources supporting this claim, raising the possibility of their endurance or the survival of related groups in the following centuries. Some researchers suggest that Essene teachings could have influenced other religious traditions, such as Early Christianity and Mandaeism.

Etymology
Josephus uses the name Essenes in his two main accounts, The Jewish War 2.119, 158, 160 and Antiquities of the Jews, 13.171–2, but some manuscripts read here Essaion ("holding the Essenes in honour"; "a certain Essene named Manaemus"; "to hold all Essenes in honor"; "the Essenes").

In several places, however, Josephus has Essaios, which is usually assumed to mean Essene ("Judas of the Essaios race"; "Simon of the Essaios race"; "John the Essaios"; "those who are called by us Essaioi"; "Simon a man of the Essaios race"). Josephus identified the Essenes as one of the three major Jewish sects of that period.

Philo's usage is Essaioi, although he admits this Greek form of the original name, that according to his etymology signifies "holiness", to be inexact. Pliny's Latin text has Esseni.

Gabriele Boccaccini implies that a convincing etymology for the name Essene has not been found, but that the term applies to a larger group within Judea that also included the Qumran community.

It was proposed before the Dead Sea Scrolls were discovered that the name came into several Greek spellings from a Hebrew self-designation later found in some Dead Sea Scrolls, ʻosey haTorah, "'doers' or 'makers' of Torah". Although dozens of etymology suggestions have been published, this is the only etymology published before 1947 that was confirmed by Qumran text self-designation references, and it is gaining acceptance among scholars. It is recognized as the etymology of the form Ossaioi (and note that Philo also offered an O spelling) and Essaioi and Esseni spelling variations have been discussed by VanderKam, Goranson, and others. In medieval Hebrew (e.g. Sefer Yosippon) Hassidim "the Pious" replaces "Essenes". While this Hebrew name is not the etymology of Essaioi/Esseni, the Aramaic equivalent Hesi'im known from Eastern Aramaic texts has been suggested. Others suggest that Essene is a transliteration of the Hebrew word ḥiṣonim (ḥiṣon "outside"), which the Mishnah (e.g. Megillah 4:8 ) uses to describe various sectarian groups. Another theory is that the name was borrowed from a cult of devotees to Artemis in Anatolia, whose demeanor and dress somewhat resembled those of the group in Judea.

Flavius Josephus in Chapter 8 of "The Jewish War" states:

"2.(119)For there are three philosophical sects among the Jews. The followers of the first of which are the Pharisees; of the second, the Sadducees; and the third sect, which pretends to a severer discipline, are called Essenes. These last are Jews by birth, and seem to have a greater affection for each other than other sects have."

Location
According to Josephus, the Essenes had settled "not in one city" but "in large numbers in every town". Philo speaks of "more than four thousand" Essaioi living in "Palestine and Syria", more precisely, "in many cities of Judaea and in many villages and grouped in great societies of many members".

Pliny locates them "on the west side of the Dead Sea, away from the coast... [above] the town of Engeda".

Some modern scholars and archeologists have argued that Essenes inhabited the settlement at Qumran, a plateau in the Judean Desert along the Dead Sea, citing Pliny the Elder in support and giving credence that the Dead Sea Scrolls are the product of the Essenes. This theory, though not yet conclusively proven, has come to dominate the scholarly discussion and public perception of the Essenes.

Rules, customs, theology, and beliefs
The accounts by Josephus and Philo show that the Essenes led a strictly communal life—often compared to later Christian monasticism. Many of the Essene groups appear to have been celibate, but Josephus speaks also of another "order of Essenes" that observed the practice of being engaged for three years and then becoming married. According to Josephus, they had customs and observances such as collective ownership, electing a leader to attend to the interests of the group, and obedience to the orders from their leader. Also, they were forbidden from swearing oaths and from sacrificing animals. They controlled their tempers and served as channels of peace, carrying weapons only for protection against robbers. The Essenes chose not to possess slaves but served each other and, as a result of communal ownership, did not engage in trading. Josephus and Philo provide lengthy accounts of their communal meetings, meals, and religious celebrations. This communal living has led some scholars to view the Essenes as a group practicing social and material egalitarianism.

Despite their prohibition on swearing oaths, after a three-year probationary period, new members would take an oath that included a commitment to practice piety to God and righteousness toward humanity; maintain a pure lifestyle; abstain from criminal and immoral activities; transmit their rules uncorrupted; and preserve the books of the Essenes and the names of the angels. Their theology included belief in the immortality of the soul and that they would receive their souls back after death. Part of their activities included purification by water rituals which was supported by rainwater catchment and storage. According to the Community Rule, repentance was a prerequisite to water purification.

Ritual purification was a common practice among the peoples of Judea during this period and was thus not specific to the Essenes. A ritual bath or mikveh was found near many synagogues of the period continuing into modern times. Purity and cleanliness was considered so important to the Essenes that they would refrain from defecation on the Sabbath.

According to Joseph Lightfoot, the Church Father Epiphanius (writing in the 4th century CE) seems to make a distinction between two main groups within the Essenes: "Of those that came before his [Elxai, an Ossaean prophet] time and during it, the Ossaeans and the Nasaraeans."Part 18 Epiphanius describes each group as following:

"The Nasaraean—they were Jews by nationality—originally from Gileaditis, Bashanitis and the Transjordan... They acknowledged Moses and believed that he had received laws—not this law, however, but some other. And so, they were Jews who kept all the Jewish observances, but they would not offer sacrifice or eat meat. They considered it unlawful to eat meat or make sacrifices with it. They claim that these Books are fictions, and that none of these customs were instituted by the fathers. This was the difference between the Nasaraean and the others..." "After this Nasaraean sect in turn comes another closely connected with them, called the Ossaeans. These are Jews like the former... originally came from Nabataea, Ituraea, Moabitis, and Arielis, the lands beyond the basin of what sacred scripture called the Salt Sea... Though it is different from the other six of these seven sects, it causes schism only by forbidding the books of Moses like the Nasaraean."We do not know much about the canon of the Essenes, and what their attitude was towards the apocryphal writings, however the Essenes perhaps did not esteem the book of Esther highly as manuscripts of Esther are completely absent in Qumran, likely because of their opposition to mixed marriages and the use of different calendars.

The Essenes were unique for their time for being against the practice of slave-ownership, and slavery, which they regarded as unjust and ungodly, regarding all men as having been born equal.

Calendar
The Dead Sea Scrolls Uncovered, a translation by Robert Eisenman and Michael Wise, reveals the Essene calendar as celebrating the Sabbath commencing on the 4th day of Abib (Nisan) page 192 3 days after the new moon of the Passover month then celebrated on the 11th, 18th and 25th. The second Essene month reveals a Sabbath on the second day exactly 7 days from the 25th of Abib Sabbath witnessing a solar calendar continuation. Page 193 of the same translation reveals a second recalibration commencing at the 2nd equinox where at the beginning of the 7th Month of The Feast of Trumpets the Sabbath commences again on the 4th day 3 days after the New Moon. The Essenes did it this way because in Genesis it reads God made the moon on the 4th day and rested 3 days later. The New Moon is the first day of the Hebrew month.

Involvement in the First Jewish–Roman War
At the outset of the First Jewish–Roman War in 66 CE, as Roman advances were anticipated, command over parts of western Judea was assigned to John the Essene (or Essaean), who was placed in charge of the toparchy of Thamna. This region encompassed Lydda, Joppa, and Emmaus.

Scholarly discussion
Josephus and Philo discuss the Essenes in detail. Most scholars believe that the community at Qumran that most likely produced the Dead Sea Scrolls was an offshoot of the Essenes. However, this theory has been disputed by some; for example, Norman Golb argues that the primary research on the Qumran documents and ruins (by Father Roland de Vaux, from the École Biblique et Archéologique de Jérusalem) lacked scientific method, and drew wrong conclusions that comfortably entered the academic canon. For Golb, the number of documents is too extensive and includes many different writing styles and calligraphies; the ruins seem to have been a fortress, used as a military base for a very long period of time—including the 1st century—so they therefore could not have been inhabited by the Essenes; and the large graveyard excavated in 1870, just 50 m east of the Qumran ruins, was made of over 1200 tombs that included many women and children; Pliny clearly wrote that the Essenes who lived near the Dead Sea "had not one woman, had renounced all pleasure... and no one was born in their race". Golb's book presents observations about de Vaux's premature conclusions and their uncontroverted acceptance by the general academic community. He states that the documents probably stemmed from various libraries in Jerusalem, kept safe in the desert from the Roman invasions. Other scholars refute these arguments—particularly since Josephus describes some Essenes as allowing marriage.

Another issue is the relationship between the Essaioi and Philo's Therapeutae and Therapeutrides. He regarded the Therapeutae as a contemplative branch of the Essaioi who, he said, pursued an active life.

One theory on the formation of the Essenes suggests that the movement was founded by a Jewish high priest, dubbed by the Essenes the Teacher of Righteousness, whose office had been usurped by Jonathan (of priestly but not of Zadokite lineage), labeled the "man of lies" or "false priest". Others follow this line and a few argue that the Teacher of Righteousness was not only the leader of the Essenes at Qumran, but was also identical to the original Messianic figure about 150 years before the time of the Gospels. Fred Gladstone Bratton notes that "The Teacher of Righteousness of the Scrolls would seem to be a prototype of Jesus, for both spoke of the New Covenant; they preached a similar gospel; each was regarded as a Savior or Redeemer; and each was condemned and put to death by reactionary factions... We do not know whether Jesus was an Essene, but some scholars feel that he was at least influenced by them." Lawrence Schiffman has argued that the Qumran community may be called Sadducean, and not Essene, since their legal positions retain a link with Sadducean tradition.

Christianity
Rituals of the Essenes and Christianity have much in common; the Dead Sea Scrolls describe a meal of bread and wine that will be instituted by the messiah, both the Essenes and Christians were eschatological communities, where judgement on the world would come at any time. The New Testament also possibly quotes writings used by the Qumran community. Luke 1:31-35 states " And now you will conceive in your womb and bear a son and you will name him Jesus. He will be great and will be called the son of the Most High...the son of God" which seems to echo 4Q 246, stating: "He will be called great and he will be called Son of God, and they will call him Son of the Most High...He will judge the earth in righteousness...and every nation will bow down to him".

Other similarities include high devotion to the faith even to the point of martyrdom, communal prayer, self denial and a belief in a captivity in a sinful world.

John the Baptist has also been argued to have been an Essene, as there are numerous parallels between John's mission and the Essenes, which suggests he perhaps was trained by the Essene community.

In the early church a book called the Odes of Solomon was written. The writer was likely a very early convert from the Essene community into Christianity. The book reflects a mixture of mystical ideas of the Essene community with Christian concepts.

Both the Essenes and Christians practiced voluntary celibacy and prohibited divorce. Both also used concepts of "light" and "darkness" for good and evil.

A few have argued that the Essenes had an idea of a pierced Messiah based on 4Q285; however, the interpretation of the text is ambiguous. Some scholars interpreted it as the Messiah being killed himself, while modern scholars mostly interpret it as the Messiah executing the enemies of Israel in an eschatological war.

Both the Essenes and Christians practiced a ritual of immersion by water, however the Essenes had it as a regular practice instead of a one time event.

Mandaeism
The Haran Gawaita uses the name Nasoraeans for the Mandaeans arriving from Jerusalem meaning guardians or possessors of secret rites and knowledge. Scholars such as Kurt Rudolph, Rudolf Macúch, Mark Lidzbarski and Ethel S. Drower connect the Mandaeans with the Nasaraeans described by Epiphanius, a group within the Essenes according to Joseph Lightfoot. Epiphanius says (29:6) that they existed before Jesus. That is questioned by some, but others accept the pre-Christian origin of the Nasaraeans.

Early religious concepts and terminologies recur in the Dead Sea Scrolls, and Yardena (Jordan) has been the name of every baptismal water in Mandaeism. One of the names for the Mandaean God Hayyi Rabbi, Mara d-Rabuta (Lord of Greatness) is found in the Genesis Apocryphon II, 4. Another early self-appellation is bhiri zidqa meaning 'elect of righteousness' or 'the chosen righteous', a term found in the Book of Enoch and Genesis Apocryphon II, 4. As Nasoraeans, Mandaeans believe that they constitute the true congregation of bnai nhura meaning 'Sons of Light', a term used by the Essenes. Mandaean scripture affirms that the Mandaeans descend directly from John the Baptist's original Nasoraean Mandaean disciples in Jerusalem. Similar to the Essenes, it is forbidden for a Mandaean to reveal the names of the angels to a gentile. Essene graves are oriented north–south and a Mandaean's grave must also be in the north–south direction so that if the dead Mandaean were stood upright, they would face north. Mandaeans have an oral tradition that some were originally vegetarian and also similar to the Essenes, they are pacifists.

The beit manda (beth manda) is described as biniana rab ḏ-srara ("the Great building of Truth") and bit tušlima ("house of Perfection") in Mandaean texts such as the Qolasta, Ginza Rabba, and the Mandaean Book of John. The only known literary parallels are in Essene texts from Qumran such as the Community Rule, which has similar phrases such as the "house of Perfection and Truth in Israel" (Community Rule 1QS VIII 9) and "house of Truth in Israel."

Magarites
The Magharians or Magarites (Al-Maghariyyah, 'people of the caves') were, according to Jacob Qirqisani, a Jewish sect founded in the 1st century BCE. Abraham Harkavy and others identify the Magharians with the Essenes, and their author referred to as the "Alexandrinian" with Philo (whose affinity for the Essenes is well-known), based on the following evidence:
 * The sect's name, which, in his view, does not refer to its books but to its followers who lived in caves or desert areas—an established Essene lifestyle;
 * The sect's founding date coinciding with that of the Essenes;
 * The theory that God interacts with humans through an angel aligning with Essene beliefs, as well as Philo's concept of the Logos;
 * Qirqisani's omission of the Essenes from his list of Jewish sects, which can be explained if he considered the Magharians to be synonymous with the Essenes.

title: Essenes