If arithmetic is only one branch of mathematics, how many other branches of mathematics are there?
There are different ways of answering this question, but to put it simply, I would break it down like this (and others can add to this list if they like):
Algebra: Subcategories of this topic include linear algebra, abstract algebra, multilinear algebra, commutative algebra, etc.
Analysis: Includes harmonic analysis, functional analysis, etc.
Topology: point-set topology, low-dimensional topology, differential topology, algebraic topology, etc.
Geometry: Euclidean geometry, non-Euclidean geometry, discrete geometry, etc.
Number theory: elementary number theory, analytic number theory, algebraic number theory, etc.
Applied math: statistics, probability theory, numerical analysis, etc.
Combinatorics: graph theory, coding theory, etc.
In addition, there are some areas that combine methods from different areas of mathematics. For example, algebraic topology takes methods from algebra to solve problems in topology. We can probably stick this under topology but that wouldn't exactly be correct. Another obstacle to creating neat divisions between branches of math is category theory, which could be thought of as existing above all of the other branches.
So in this framework, we have six branches with their varying subtopics, and some subtopics belong to one or more branches, and some, such as category, not belonging to any branch. This list could be criticized for being incomplete or grossly generalistic, but is probably sufficient for someone who is a high school student or first-year college student thinking about deeper study of math. (TriviaFan22)
2 answers
Jul 09 25 by odo5435
If arithmetic is only one branch of mathematics, how many other branches of mathematics are there?
How long is a piece of string? Seriously, the answer is constantly changing, from the pre-Renaissance idea that there were two fields (arithmetic and geometry) to the 2020 classification of mathematical topics used by people producing research papers to identify the field in which their work fits. It has 63 top-level groupings, each of which has multiple subcategories. These are listed here.
https://en.wikipedia.org/wiki/Mathematics_Subject_Classification#First-level_areas (looney_tunes)
2 answers
Jul 09 25 by odo5435
Which African head of state sold the government's fleet of expensive Mercedes cars in the 1980s and made a Renault 5 the ministers' official car?
Thomas Sankara, at the age of 33, became the President of the Republic of Upper Volta after a military coup in 1983 and made a long list of series of social, ecological, and economic reforms. He renamed the country as Burkina Faso ('land of the upright people'), and wrote the new national anthem himself. His many radical reforms were aimed at making his country more self-sufficient. Among his more populist reforms, he sold off the government fleet of Mercedes vehicles and made the cheapest car sold in Burkina Faso at that time, the Renault 5, the official vehicle for ministers. He was assassinated in 1987.
https://en.wikipedia.org/wiki/Thomas_Sankara
https://www.thomassankara.net/?lang=en (1nn1)
1 answer
Jul 09 25 by pehinhota
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Jul 09 25 by Thesuperyoshi
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Jul 08 25 by pehinhota
This now defunct company had its main factory in what is now the Czech Republic and its name is a portmanteau of two English words (one misspelt). It popularised something found in libraries across the USA and beyond, which are named after a profession in another setting (i.e. not librarian). What are the company and the object so described?
Emeralite Inc ceased to exist in 1962. It had changed its name to Tilarem Inc in 1960 and was dissolved two years later. [quote] What is the story behind the green desk lamp that appears on film so often? Who made green banker lamps?
The official name of this lamp is the Emeralite Desk Lamp, which is also widely known as the Bankers Lamp. The inventor is Harrison D. McFaddin, who made various types of lamps. The signature feature of his lamps is the emerald green lampshade, known as the Emerald Shades. He established the H.G. McFaddin & Co. company to produce this type of lamp. The main factory was located in the city of Rapotin, Moravia, which is now part of the Czech Republic. The earliest Bellova and Emeralite lamps were born in 1909. On May 11th of the same year, they obtained the original appearance patent in the United States (patent number 39984), and they were produced for 50 years. The glass factory of J. Schreiber & Neffen specialized in producing the lampshade for this lamp. It is said that many bankers who work late into the night liked this lamp, hence it is also called the banker's lamp ...
In 1939, the founder wanted to retire, and then the company was acquired by an employee named Charles Inness Brown and was renamed The Emeralite Co., Inc. The production direction also shifted from the collectible art lamps of Emeralite and Bellova to more modern models, but naturally, it also lost its original value. By the 1950s, the company's profits were very problematic. After Inness-Brown died in 1960, the company was transferred again, and the company was renamed once more to Tilarem, Inc. (which is the original company name with the first and last letters removed and then reversed, quite creative~). By 1962, the company was completely dissolved. It became history.[/quote] https://www.cordless-lamps.com/en-au/blogs/news/what-is-the-story-behind-the-green-desk-lamp-that-appears-on-film-so-often-who-made-green-banker-lamps
(gtho4)
2 answers
Jul 06 25 by gmackematix
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Jul 06 25 by gmackematix
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Jul 07 25 by pehinhota
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Jul 03 25 by chabenao1
How did Residente and Visitante, members of the hip-hop group Calle 13, get their stage names?
Residente and Visitante adopted their stage names from a system used in the gated community in Trujillo Alto, Puerto Rico, where they grew up.
René Pérez Joglar (Residente) lived inside the community. When he returned home, he would tell the security guard he was a "residente" (resident).
His stepbrother Eduardo Cabra (Visitante) lived elsewhere. When he came to visit René, he had to register at the gate as a "visitante" (visitor).
https://en.wikipedia.org/wiki/Calle_13_(band)#2004-2005:_early_years (wellenbrecher)
1 answer
Jul 06 25 by Thesuperyoshi
1 answer
Jul 05 25 by gmackematix
What does the song "Salma Ya Salama" (Dalida 1976) translate as?
"Welcome Back To Safety"
[quote]We also hear the strains of "Salma Ya Salama" (Welcome Back to Safety), another renowned Darwish song, being sung in Tahrir. This tune celebrated the return of Egyptian laborers recruited (usually by coercion) to assist in the war effort in World War I. The workers numbered about 1 million. The song was an immediate hit and has remained popular ever since. It has been recorded by many artists, most famously in 1997 by Dalida, the Egyptian-born French music star.[/quote]
https://merip.org/2012/02/traditions-of-tahrir/ (elburcher)
1 answer
Jul 05 25 by chabenao1
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Jun 17 25 by Thesuperyoshi
Did any chess player have a positive score against Bobby Fisher or Mikhail Tal?
Tigran Petrosian beat Mikhail Tal 6 to 4, with 35 draws in classical games. Including rapid/exhibition games: Tigran Petrosian beat Mikhail Tal 6 to 5, with 36 draws.
https://www.chessgames.com/perl/ezsearch.pl?search=Petrosian-tal
Anatoly Karpov beat Mikhail Tal 1 to 0, with 19 draws in classical games. Including rapid/exhibition games: Anatoly Karpov beat Mikhail Tal 2 to 1, with 19 draws.
https://www.chessgames.com/perl/ezsearch.pl?search=Karpov-tal (wellenbrecher)
2 answers
Jun 18 25 by chabenao1
3 answers
Jun 27 25 by apathy100
Why is "orange" (the fruit) called "Burtukal" (Portugal) in Arabic?
Oranges are not native to Europe or the Middle East. They were originally cultivated in southern China and northern India, and only reached the Mediterranean region much later via trade routes.
During the 15th and 16th centuries, it was Portuguese traders who played a key role in bringing sweet oranges from Asia to Europe and North Africa. As they spread through the Arab world, Arabic speakers began to associate the fruit with the people who had brought it: the Portuguese. Consequently, in many Arabic dialects, the word for orange became "burtuqal", which literally means "Portugal".
But Arabic isn't alone. Many other languages in the Middle East and Southeastern Europe have had the same idea.
Greek: portokáli
Turkish: portakal
Amharic: burtukan
Albanian: portokalli
Romanian: portocala
Bulgarian: portokal
Macedonian: portokal
Kurdish: pirteqal
Georgian: portokhali
Azeri: portagal
https://www.reddit.com/r/linguistics/comments/1cmhsv/the_word_for_the_fruit_orange_in_various_european/#lightbox (wellenbrecher)
1 answer
Jul 04 25 by chabenao1
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Jul 04 25 by Thesuperyoshi
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Jul 03 25 by pehinhota
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Jul 03 25 by chabenao1
4 answers
Jul 03 25 by chabenao1
What is the largest and heaviest animal found in South America?
The South American tapir is the largest and heaviest animal found in South America. They can weigh up to 700 pounds (318 kg). I'm not sure what defines the largest but the green anaconda can reach lengths of up to 30 feet.
https://colombiaone.com/2025/06/28/tapir-south-america-brazil/ (Triviaballer)
4 answers
Jul 03 25 by chabenao1
1 answer
Jun 30 25 by unclerick
Who is the lowest drafted NHL player to play at least 1000 games and have a successful career?
Martin St. Louis was undrafted in the 1997 NHL draft (8 rounds; 246 picks) and had to go play for the Cleveland Lumberjacks in the IHL to keep playing in fall 1997. (He was only 5'8" and had played college hockey in the U.S., which was then not respected by the NHL.) However, he eventually ended up playing 1,134 games in the NHL (mostly with Tampa Bay), won the MVP award in 2003-4, and was elected to the Hockey Hall of Fame in 2018, his first year of eligibility.
https://en.m.wikipedia.org/wiki/Martin_St._Louis (AyatollahK)
3 answers
Jun 27 25 by apathy100
Which is the longest-running show, "Cats" or "Les Miz"?
All of the above pale to London's West End Play "The Mousetrap" which ran from October 6, 1952 until it was shut down for COVID March 16, 2020, it reopened May 17, 2021 and is still going. It celebrated 30,000th performance March 19, 2025 it's 73rd year,
That makes its initial run from 1952 to 2020
24,634 days that's 67 years, 5 months and 11 days!
https://themousetrap.com/
(elburcher)
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Jun 27 25 by chabenao1
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Jun 28 25 by pehinhota
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Jun 27 25 by apathy100
Which is the longest-running show, "Cats" or "Les Miz"?
It depends on where you look.
On Broadway, Cats defeats Les Mis by two years, 18 years to 16.
https://en.wikipedia.org/wiki/List_of_the_longest-running_Broadway_shows
In London's West End, Les Mis is ahead by at least 19 years - it is still running in year 40, while Cats was cancelled on its 21st anniversary.
https://en.wikipedia.org/wiki/List_of_the_longest-running_West_End_shows
Worldwide, Cats defeats Les Mis simply by virtue of being four years older - both shows always had at least one running instance somewhere (Cats has been running continuously in Tokyo since the 1990s - combined with the West End run up to 2003, these two provide for at least one performing theater at all times)
Another extremely long run is Starlight Express in Bochum, Germany, where a hall was specifically built for the show. It started in 1988 and is still going strong there.
https://en.wikipedia.org/wiki/Starlight_Express (WesleyCrusher)
2 answers
Jun 27 25 by chabenao1
If the national cricket teams of two nations not currently among the ICC "Test" nations were to meet and play a 5-day match according to test rules, what status would that match have? Could it be counted as a sanctioned international at all or would it be no better than two amateur village teams playing a 5-day match?
This is purely hypothetical. To my knowledge (and just researched) this type of match has never taken place since the formation of the International Cricket Council (ICC). An answer can only be speculative.
It is a long way from a 'village' cricket match to an international 'Test' match. There are currently 12 'full' Test playing members of the ICC.
https://en.wikipedia.org/wiki/List_of_International_Cricket_Council_members#Full_members
The road to full membership is demanding. It requires achieving 'associate' membership by meeting several criteria and then meeting further conditions to apply for 'full' membership. [quote]In order for a nation to apply for associate membership they must meet 5 criteria given by the ICC:[12][13]
An appropriate domestic cricket structure.
A recognized administrative governing body.
Proper domestic cricket competitions.
At least two cricket grounds in the country.
A "National Development Plan" and an annual budget.
For an associate member to apply for full membership they must have the following in-addition to the above criteria:[12][13]
At least three appearances in men's Cricket World Cups or men's T20 World Cups in the last ICC men's hosts cycle.
Four wins against two or more full members over the last ICC men's hosts cycle.
At least one appearance in women's Cricket World Cup or women's T20 World Cup in the last ICC women's hosts cycle.
Currently present on the ICC Women's ODI Team Rankings.
If a member country (full or associate) fails to adhere to the ICC membership criteria, they will be suspended or expelled by the ICC.[14][15][/quote]https://en.wikipedia.org/wiki/List_of_International_Cricket_Council_members
Therefore, if a five day match such a that proposed in the question was to take place, it would NOT be a 'Test' match. The match might possibly be 'sanctioned' by the ICC as, say, an 'exhibition' match but that has yet to be determined. However, IMVHO, I believe such a match would receive quite an amount of attention and would be considered as somewhat more than a 'village' game.
----
BTW but not entirely off-topic, the ICC will shortly be testing (sorry) a rule change that will allow 4-day 'Test' matches (which, as a traditionalist, I find horrifying). (odo5435)
1 answer
Jun 23 25 by WesleyCrusher
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Jun 23 25 by pehinhota
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Jun 23 25 by chabenao1
Why was one of the newest federal electoral divisions in Australia named 'Bullwinkel'?
The seat was named with some controversy for Vivian Bullwinkel.
[quote]Vivian Bullwinkel, sole survivor of the 1942 Banka Island massacre, was born on 18 December 1915 at Kapunda, South Australia. She trained as a nurse and midwife at Broken Hill, New South Wales, and began her nursing career in Hamilton, Victoria, before moving to the Jessie McPherson Hospital in Melbourne in 1940.
In 1941, wanting to enlist, Bullwinkel volunteered as a nurse with the RAAF but was rejected for having flat feet. She was, however, able to join the Australian Army Nursing Service; assigned to the 2/13th Australian General Hospital (2/13th AGH), in September 1941 she sailed for Singapore. After a few weeks with the 2/10th AGH, Bullwinkel rejoined the 13th AGH in Johor Baharu.
Japanese troops invaded Malaya in December 1941 and began to advance southwards, winning a series of victories and, in late January 1942, forcing the 13th AGH to evacuate to Singapore. But the short-lived defence of the island ended in defeat, and, on 12 February, Bullwinkel and 65 other nurses boarded the SS Vyner Brooke to escape the island.
Two days later, the ship was sunk by Japanese aircraft. Bullwinkel, 21 other nurses and a large group of men, women, and children made it ashore at Radji Beach on Banka Island; they were joined the next day by about 100 British soldiers. The group elected to surrender to the Japanese, and while the civilian women and children left in search of someone to whom they might surrender, the nurses, soldiers, and wounded waited.
Some Japanese soldiers came and killed the men, then motioned the nurses to wade into the sea. They then machine-gunned the nurses from behind. Bullwinkel was struck by a bullet and pretended to be dead until the Japanese left. She hid with a wounded British private for 12 days before deciding once again to surrender. They were taken into captivity, but the private died soon after. Bullwinkel was reunited with survivors of the Vyner Brooke. She told them of the massacre, but none spoke of it again until after the war lest it put Bullwinkel, as witness to the massacre, in danger. Bullwinkel spent three and half years in captivity; she was one of just 24 of the 65 nurses who had been on the Vyner Brooke to survive the war.
Bullwinkel retired from the army in 1947 and became Director of Nursing at Melbourne's Fairfield Hospital. She devoted herself to the nursing profession and to honouring those killed on Banka Island, raising funds for a nurses' memorial and serving on numerous committees, including a period as a member of the Council of the Australian War Memorial, and later president of the Australian College of Nursing.
In the decades following the war, Bullwinkel received many honours and awards, including the Florence Nightingale Medal, an MBE and the AO. She married in 1977 and returned to Banka Island in 1992 to unveil a shrine to the nurses who had not survived the war. Vivian Bullwinkel died on 3 July 2000.[/quote]
https://www.awm.gov.au/collection/P10676383
https://www.aec.gov.au/profiles/wa/bullwinkel.htm (elburcher)
1 answer
Jun 22 25 by odo5435
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Jun 22 25 by odo5435
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Jun 22 25 by odo5435
Why would a hydrometer be used instead of a hygrometer?
Important applications for a hydrometer include winemaking and brewing when measurements of a liquid's density is important. A hydrometer measures the specific gravity or density of a liquid whereas a hygrometer measures the amount of water vapor in the air (humidity).
https://en.wikipedia.org/wiki/Hydrometer#:~:text=Not%20to%20be%20confused%20with,read%20off%20the%20scale%20A. (Triviaballer)
1 answer
Jun 22 25 by odo5435
What is the difference between, and the correct usage of, the words "toward" and "towards"?
They are completely interchangeable and have both been used since they first appeared in English in the 9th century. In North America, people are more likely to use toward, while everywhere else towards is more common. Both forms, however, are used everywhere and both are completely correct. There have been some suggestions about different usages (e.g., one is the adjective, one the adverb or preposition), but they are not widely accepted, and are at variance with the fact that both forms have always been used interchangeably.
https://www.merriam-webster.com/grammar/toward-towards-usage
(It's a bit like grey vs gray.)
(looney_tunes)
1 answer
Jun 20 25 by RedRobin7
How many named seas are recognized in the English language?
Since there are a number of regions which are named as seas by locals, and there is no official designation of exact areas defined by specific names, there cannot be a definitive answer to this question. This page lists a large number of seas, but excludes any that are not part of the World Ocean (the major named oceans and their branches as bays, etc.) - so there are more places called a sea, but the exact number is indeterminate. Given those provisos, I cannot be bothered counting the entries, and checking to make sure that any listed under more than one category have only been counted once. Others may have the necessary energy for the task.
[quote]Sea has several definitions:
*A division of an ocean, delineated by landforms, currents (e.g., Sargasso Sea), or specific latitude or longitude boundaries. This includes but is not limited to marginal seas, and this is the definition used for inclusion in this list.
*A marginal sea is a division of an ocean, partially enclosed by islands, archipelagos, or peninsulas, adjacent to or widely open to the open ocean at the surface, and/or bounded by submarine ridges on the sea floor.
*The World Ocean. For example, the Law of the Sea states that all of the World Ocean is "sea", and this is also common usage for "the sea".
*Any large body of water with "Sea" in the name, including lakes.
...
Entities called "seas" which are not divisions of the World Ocean are not included in this list. Excluded are:
Lakes, ponds, etc.: Salt lakes with "Sea" in the name: Aral Sea, Dead Sea, Caspian Sea, Salton Sea; Freshwater lakes with "Sea" in the name: Sea of Galilee
...
(Note) There is no accepted technical definition of sea among oceanographers. A rather weak definition is that a sea is a subdivision of an ocean, which means that it must have oceanic basin crust on its floor. This definition, for example, accepts the Caspian Sea, which was once part of an ancient ocean, as a sea. The Introduction to Marine Biology defines a sea as a "landlocked" body of water, adding that the term "sea" is only one of convenience, but the book is written by marine biologists, not oceanographers. The Glossary of Mapping Sciences similarly states that the boundaries between seas and other bodies of water are arbitrary.[/quote]
https://en.wikipedia.org/wiki/List_of_seas_on_Earth (looney_tunes)
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Jun 20 25 by RedRobin7
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Jun 20 25 by RedRobin7
What was the first area code in the USA to have a middle digit other than 0 or 1?
In 1947, the USA was divided into 86 different telephone area codes, which were defined as having three digits, with the middle digit being 0 or 1, as these numbers were not used in the previous assignment of two-digit area codes. At first, area codes with the middle digit 0 were assigned to a plan area that comprised an entire state, but states with multiple numbering plan areas received area codes having 1 as the second digit. Eg Oregon was assigned 503, but California received 213, 415, and 916.
After valid area codes were used up by expansion, there was a need to allow the digits 2 through 8 to be used as a middle digit in new area code assignments (with 9 being reserved for even more future expansion). "The first area codes without a 1 or 0 as the middle digit were area code 334 in Alabama and area code 360 in Washington, which both began service on January 15, 1995. This was followed quickly by area code 520 serving Arizona on March 19, 1995'.
https://en.wikipedia.org/wiki/Original_North_American_area_codes
https://en.wikipedia.org/wiki/North_American_Numbering_Plan (1nn1)
1 answer
Jun 19 25 by serpa
Did any chess player have a positive score against Bobby Fisher or Mikhail Tal?
Efim Geller had a record of 5 wins, 3 losses and 2 draws against Bobby Fischer
https://www.chessgames.com/perl/chessplayer?pid=15712
https://www.chessgames.com/perl/chess.pl?yearcomp=exactly&year=&playercomp=either&pid=19233&player=&pid2=15712&player2=&movescomp=exactly&moves=&opening=&eco=&result=
Boris Spassky was 9 wins, 6 losses and 27 draws against Mikhail Tal
https://www.chessgames.com/perl/chess.pl?yearcomp=exactly&year=&playercomp=either&pid=14380&player=&pid2=21136&player2=&movescomp=exactly&moves=&opening=&eco=&result=
Lev Polugaevsky was 8 wins, 2 losses and 23 draws against Mikhail Tal
https://www.chessgames.com/perl/chess.pl?yearcomp=exactly&year=&playercomp=either&pid=14380&player=&pid2=&player2=Polugaevsky&movescomp=exactly&moves=&opening=&eco=&result= (elburcher)
2 answers
Jun 18 25 by chabenao1
1 answer
Jun 17 25 by pehinhota