Asymmetric (pronounced a-sim-et-rick)
(1) Not identical on both sides of a central line;
unsymmetrical; lacking symmetry.
(2) An asymmetric shape.
(3) In logic or mathematics, holding true of members of a
class in one order but not in the opposite order, as in the relation “being an ancestor
of”.
(4) In chemistry, having an unsymmetrical arrangement of
atoms in a molecule.
(5) In chemistry, noting a carbon atom bonded to four different atoms or
groups.
(6) In chemistry (of a polymer), noting an atom or group that
is within a polymer chain and is bonded to two different atoms or groups that
are external to the chain.
(7) In electrical engineering, of conductors having different
conductivities depending on the direction of current flow, as of diodes
(8) In aeronautics, having unequal thrust, as caused by an
inoperative engine in a twin-engined aircraft.
(9) In military theory, a conflict where the
parties are vastly different in terms of military capacity. This situation is not in all circumstances
disadvantageous to the nominally inferior party.
(10) In gameplay, where different players have different experiences
(11) In cryptography, not involving a mutual exchange of keys between sender a7 receiver.
(12) In set theory, of a relation R on a set S: having the property that for any two elements of S (not necessarily distinct), at least one is not related to the other via R.
1870–1875: The construct was a- + symmetric. The a- prefix was from the Ancient Greek ἀ- (a-) (ἀν-) (an- if immediately preceding a vowel) and was added to stems to created the sense of "not, without, opposite of". The prefix is referred to as an alpha privative and is used with stems beginning with consonants (except sometimes “h”); “an-“ is synonymous and is used in front of words that start with vowels and sometimes “h”. Symmetric was from the Latin symmetria from Ancient Greek συμμετρία (summetría). Symmetry was from the 1560s in the sense of "relation of parts, proportion", from the sixteenth century French symmétrie and directly from the Latin symmetria, from the Greek symmetria (agreement in dimensions, due proportion, arrangement", from symmetros (having a common measure, even, proportionate), an assimilated form of syn- (together) + metron (measure) from the primitive Indo-European me- (to measure). The meaning "harmonic arrangement of parts" dates from the 1590s. The suffix -ic was from the Middle English -ik, from the Old French -ique, from the Latin -icus, from the primitive Indo-European -kos & -ḱos, formed with the i-stem suffix -i- and the adjectival suffix -kos & -ḱos. The form existed also in Ancient Greek as -ικός (-ikós), in Sanskrit as -इक (-ika) and the Old Church Slavonic as -ъкъ (-ŭkŭ); A doublet of -y. In European languages, adding -kos to noun stems carried the meaning "characteristic of, like, typical, pertaining to" while on adjectival stems it acted emphatically. In English it's always been used to form adjectives from nouns with the meaning “of or pertaining to”. A precise technical use exists in physical chemistry where it's used to denote certain chemical compounds in which a specified chemical element has a higher oxidation number than in the equivalent compound whose name ends in the suffix -ous; (eg sulphuric acid (H₂SO₄) has more oxygen atoms per molecule than sulphurous acid (H₂SO₃). Asymmetric & asymmetrical are adjectives, asymmetricity, asymmetricality, asymmetricalness & asymmetry are nouns and asymmetrically is an adverb; the noun plural is asymmetries.
The usually symmetrically attired Lindsay Lohan demonstrates the possibilities of asymmetry.
Manufacturers of triple-cylinder motorcycles traditionally used single (3 into 1) or symmetrical (3 into 2) exhaust systems (although, during the 1970s, Suzuki offered some of their "Ram-Air" models with a bizarre 3 into 4 setup, the centre cylinder’s header bifurcated) but in 1969 Kawasaki adopted an asymmetric addition for one of the memorable machines of the time. The Kawasaki 500 H1 Mach III had two outlets to the right, one to the left and was a fast, lethally unstable thing which was soon dubbed the "widow maker". Improvements to the Mach III made it a little more manageable and its successor, the 750 H2 Mach IV was claimed to be better behaved but was faster still and best enjoyed by experts, preferably in a straight line although, with a narrow power band which peaked with a sudden rush, even that could be a challenge. The Kawasaki triples remain the most charismatic of the Japanese motorcycles.
Available only during 1972-1973 and produced in small numbers, the Triumph X75 Hurricane was typical of the motorcycles being produced by the British manufacturers which had neglected development and re-investment and consequently were unable adequately to respond to the offerings of the Japanese which had done both aplenty. Whatever their charms, models like the X75 were being rendered obsolescent, some of the underlying technology dating back decades yet, without the capital to invest, this was as good as it got and some of the fudges of the era were worse. The X-75 was however ahead of its time in one way, it was a “factory special”, a design influenced by what custom shops in the US had been doing as one-offs for customers and in the years ahead, many manufacturers would be attracted by the concept and its healthy profit margins. The X-75 is remembered also for the distinctive asymmetric stack of three exhaust pipes on the right-hand side.
1986 Ferrari Testarossa (1984-1991) with monospecchio.
Some of Ferrari's early-production Testarossas were fitted with a single high-mounted external mirror, on the left or right depending on the market into which it was sold and although the preferred term was the Italian “monospecchio” (one mirror), in the English speaking-world it was quickly dubbed the “flying mirror" (rendered sometimes in Italian as “specchio volante” (a ordinary wing mirror being a “specchietto laterale esterno”, proving everything sounds better in Italian)). The unusual placement and blatant asymmetry annoyed some and delighted others, the unhappy more disgruntled still if they noticed the vent on right of the front spoiler not being matched by one to the left. It was there to feed the air-conditioning’s radiator and while such offset singularities are not unusual in cars, many manufacturers create a matching fake as an aesthetic device: Ferrari did not. The mirror’s curious placement was an unintended consequence of a European Union regulation (and it doubtful many institutions have in a relatively short time created as many regulations of such collective length as the EU) regarding the devices and this was interpreted by the designers as having to provide 100% rearward visibility. Because of the sheer size of the rear bodywork necessitated by the twin radiators which sat behind the side-strakes (another distinctive Testarossa feature), the elevation was the only way this could be done but it later transpired the interpretation of the law was wrong, a perhaps forgivable mistake given the turgidity of EU legalese.
The Blohm & Voss BV 141
In aircraft, designs have for very good reason (aerodynamics, weight distribution, flying characteristics, ease of manufacture et al) tended to be symmetrical, sometimes as an engineering necessity such as the use of contra-rotationg propellers on some twin-engined airframes, a trick to offset the destabilizing effects of the torque when very potent power-plants are fitted. There has though been the odd bizarre venture into structural asymmetry, one of the most intriguing being the Blohm & Voss BV 141, the most distinctive feature of which was an offset crew-capsule. The BV 141 was tactical reconnaissance aircraft built in small numbers and used in a desultory manner by the Luftwaffe (the German air force) during World War II (1939-1945) and although it was studied by engineers from many countries, none seem to have been inspired to repeat the experiment. The origin of the curious craft lay in a specification issued in 1937 by the Reichsluftfahrtministerium (RLM; the German Air Ministry) which called for a single-engine reconnaissance aircraft, optimized for visual observation and, in response, Focke-Wulf responded with their Fw 189 Eurl (Owl) which, because of the then still novel twin-boomed layout, encountered some resistance from the RLM bureaucrats but it found much favor with the Luftwaffe and, over the course of the war, some nine-hundred entered service and it was used almost exclusively as the German's standard battlefield reconnaissance aircraft. In fact, so successful did it prove in this role that the other configurations it was designed to accommodate, that of liaison and close-support ground-attack, were never pursued. Although its performance was modest, it was a fine airframe with superb flying qualities and an ability to absorb punishment which, on the Russian front where it was extensively deployed, became famous and captured examples provide Russian aeronautical engineers with ides which would for years influence their designs.
The RLM had also invited Arado to tender but their Ar 198, although featuring an unusual under-slung and elongated cupola which afforded for the observer a uniquely panoramic view, proved unsatisfactory in test-flights and development ceased. Blohm and Voss hadn't been included in the RLM's invitation but anyway chose to offer a design which was radically different even by the standards of the innovative Fw 189. The asymmetric BV 141 design was eye-catching with the crew housed in an extensively glazed capsule, offset to starboard of the centre-line with a boom offset to the left which housed the single-engine in front with the tail to the rear. Prototypes were built as early as 1938 and the Luftwaffe conducted operational trials over both the UK and USSR between 1939-1941 but, despite being satisfactory in most respects, the Bv 141 was hampered by poor performance, a consequence of using an under-powered engined. A re-design of the structure to accommodate more powerful units was begun but delays in development and the urgent need for the up-rated engines for machines already in production doomed the project and the Bv 141 was in 1943 abandoned.
Blohm & Voss BV 141 prototype with full-width rear elevators & stabilizers.
Despite the ungainly appearance, test-pilots reported the Fw 141 was a nicely balanced airframe, the seemingly strange weight distribution well compensated by (1) component placement, (2) the specific lift characteristics of the wing design and (3) the choice of opposite rotational direction for crankshaft and propeller, the torque generated used as a counter-balance. Nor, despite the expectation of some, were there difficulties in handling whatever behavior was induced by the thrust versus drag asymmetry and pilots all indicated some intuitive trimming was all that was needed to compensate for any induced yaw. The asymmetry extended even to the tail-plane, the starboard elevator and horizontal stabilizer removed (to afford the tail-gunner a wider field of fire) after the first three prototypes were built; surprisingly, this was said barely to affect the flying characteristics. Focke-Wolf pursued the concept, a number of design-studies (including a piston & turbojet-engine hybrid) initiated but none progressed beyond the drawing-board.
Asymmetric warfare
In the twenty-first century, the term “asymmetric warfare” became widely used. The concept describes conflicts in which there are significant disparities in power, capability and strategies between opposing forces and although the phrase has become recently fashionable, the idea is ancient, based often on the successes which could be exploited by small, mobile and agile (often irregular) forces against larger, conventionally assembled formations. Reports of such tactics are found in accounts of conflicts in Asia, Africa, the Middle East and Europe from as early as reliable written records have been found. The classic example is what came later to be called “guerrilla warfare”, hit-and-run tactics which probe and attack a weak spots as they are detected, the ancestor of insurgencies, “conventional” modern terrorism and cyber-attacks. However, even between conventional national militaries there have long been examples of the asymmetric such as the use of small, cheap weapons like torpedo boats and mines which early in the twentieth century proved effective against the big, ruinously expensive Dreadnoughts. To some extent, the spike in use of the phrase in the post-Cold War era happened because it provided such a contrast between the nuclear weapon states which, although having a capacity to destroy entire countries without having one soldier step foot on their territory, found themselves vulnerable to low-tech, cleverly planned attacks.
Although
the term “asymmetric warfare” covers encompasses a wide vista, one increasingly
consistent thread is that it can be a difficult thing for
"conventional" military formations to counter insurgencies conducted
by irregular combatants who, in many places and for much of the time, are
visually indistinguishable from the civilian population. The difficulty lies not in achieving the
desired result (destruction of the enemy) but managing to do so without causing
an “excessive” number of civilian causalities; although public disapproval has
meant the awful phrase “collateral damage” is now rarely heard, civilians (many
of them women & children) continue greatly to suffer in such conflicts, the
death toll high. Thus the critique of
the retaliatory strategy of the Israel Defence Force (IDF) in response to the
attack by the Hamas on 7 October 2023, Palestinian deaths now claimed to exceed
20,000; that number is unverified and will include an unknown number of Hamas
combatants but there is no doubt the percentage of civilian deaths will be
high, the total casualty count estimated early in January 2024 at some
60,000. What the IDF appear to have done
is settle on the strategy adopted by Ulysses S Grant (1822–1885; US president
1869-1877) in 1863 when appointed head of the Union armies: the total
destruction of the opposing forces. That
decision was a reaction to the realization the previous approach (skirmishes
and the temporary taking of enemy territory which was soon re-taken) was
ineffectual and war would continue as long as the other side retained even a
defensive military capacity. Grant’s
strategy was, in effect: destroy the secessionist army and the secessionist
cause dies out.
In
the US Civil War (1861-1965) that approach worked though at an appalling cost,
the 1860s a period when ballistics had advanced to the point horrific injuries
could be inflicted at scale but battlefield medical tools and techniques were
barely advance from Napoleonic times.
The bodies were piled high.
Grant’s success was influential on the development of the US military
which eventually evolved into an organization which came to see problems as
something not to be solved but overwhelmed by the massive application of force,
an attitude which although now refined, permeates from the Pentagon down to
platoon level. As the US proved more
than once, the strategy works as long as there’s little concern about
“collateral damage”, an example of this approach being when the Sri Lankan military
rejected the argument there was “no military solution” to the long running
civil war (1983-2009) waged by the Tamil Tigers (the Liberation Tigers of Tamil
Eelam (LTTE)). What “no military
solution” means is that a war cannot be won if the rules of war are followed so
the government took the decision that if war crimes and crimes against humanity
were what was required to win, they would be committed.
In
the 1990s, a number of political and military theorists actually advanced the
doctrine “give war a chance”, the rationale being that however awful conflicts
may be, if allowed to continue to the point where one side gains an unambiguous
victory, the dispute is at least resolved and peace can ensue, sometimes for
generations. For most of human history,
such was the usual path of war but after the formation of the United Nations
(UN) in 1945 things changed, the Security Council the tool of the great powers,
all of which (despite their publicity) viewed wars as a part of whatever agenda
they were at the time pursuing and depending on this and that, that meant their
interests sometimes lay in ending conflicts and sometimes in prolonging
them. In isolation, such an arrangement
probably could have worked (albeit with much “collateral damage”) but over the
years, a roll-call of nations run by politicians appalled by the consequences
of war began to become involved, intervening with peace plans, offering mediation and urging the UN to
deploy “peacekeeping” forces, something which became an international growth
industry. Added to that, for a number of
reasons, a proliferation of non-government organizations (NGO) were formed,
many of which concerned themselves with relief programmes in conflict zones and
while these benefited may civilians, they also had the effect of allowing
combatant forces to re-group and re-arm, meaning wars could drag on for a
decade or more.
In the dreadful events in Gaza, war is certainly being given a chance and the public position of both the IDF and the Israeli government is that the strategy being pursued is one designed totally “to destroy” not merely the military capacity of Hamas but the organization itself. Such an idea worked for Grant in the 1860s and, as the Sri Lankan military predicted they would, end-game there was achieved in 2009 on the basis of “total destruction”. However, Gaza (and the wider Middle East) is a different time & place and even if the IDF succeeds in “neutralizing” the opposing fighters and destroying the now famous network of tunnels and ad-hoc weapons manufacturing centres, it can’t be predicted that Hamas in some form won’t survive and in that case, what seems most likely is that while the asymmetry of nominal capacity between the two sides will be more extreme than before, Hamas is more likely to hone the tactics than shift the objective. The IDF high command are of course realists and understand there is nothing to suggest “the Hamas problem” can be solved and being practical military types, they know if a problem can’t be solved it must be managed. In the awful calculations of asymmetric conflict, this means the IDF calculate that while future attacks will happen, the more destructive the response now, the longer will be the interval before the next event.
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