Hot answers tagged

42 votes

Why are quaternions more popular than tessarines despite being non-commutative?

Commutativity is over-rated: in fact, it holds back bicomplex numbers: It prevents your number system characterising non-commuting operations, e.g. rotations in $3$-dimensional space, Hamilton's ...
J.G.'s user avatar
  • 1,720
27 votes

Why are quaternions more popular than tessarines despite being non-commutative?

Your description "total uselessness of quaternions" in a comment above is poorly chosen, and reflects more on your interests than on the real state of knowledge of mathematics. The Hamilton ...
KCd's user avatar
  • 5,312
12 votes
Accepted

Historical origin of commas and periods in numbers

(I must admit that I'm writing this mostly from memory and I don't have sources and not enough time to look for any, so some details may be wrong.) Simon Stevin, who developed the notation of decimal ...
Stephan Matthiesen's user avatar
11 votes

Why are quaternions more popular than tessarines despite being non-commutative?

Hamilton expected that the quaternions would be of physical interest. In this, he was right. But he was too early. He had discovered them in 1843, it was almost a century later, in 1928, when Dirac ...
Mozibur Ullah's user avatar
10 votes
Accepted

Has the idea that the result of division of positive number by negative number should be negative ever been controversial?

Much has been written about various roadblocks to the acceptance of negative numbers, and I have a folder containing photocopies of a few such papers, but I don't have time now to look for that folder....
Dave L Renfro's user avatar
9 votes
Accepted

Why do South Asians often use "lakhs" and "crores" instead of "millions"? What is the historical origin of this system?

What is the origin of this special numbering system? Was there a more practical reason for having a special numbering system for South Asia? The use of the terms "lakhs" and "crores&...
Big Brother's user avatar
  • 2,157
6 votes
Accepted

When did the word "Real number" begin to be used as an official terminology to refer to both rational and irrational numbers?

It is hard to say what "official" means exactly, it is not like there was a bureau of terminological standards. But "real numbers", "real values" and "real ...
Conifold's user avatar
  • 74.8k
6 votes
Accepted

Why did the romans use IV and why doesn't it overcomplicate things?

I'd like to add my comment as an answer to have memory of a side comment. As I was saying the subtractive notation was a way of sparing characters in carving and this is the reason behind it becoming ...
Nicola Ciccoli's user avatar
6 votes

Gate 44 at the Colosseum in Rome: XLIIII or XLIV? When and why the change?

Literature on the subject seems to agree about the fact that purely additive forms, as IIII, are the most ancient forms and the preferred forms in early Roman times, and the subtractive forms as IV ...
BakerStreet's user avatar
5 votes

Did Fibonacci not grasp the idea of zero?

The nonzero digits are also numbers that were considered by the Greeks as existing entities (the case for 1 was seen as somewhat special as it is not composed of other entities; Simon Stevin notably ...
Mikhail Katz's user avatar
  • 5,421
4 votes
Accepted

Was there ever a word for 24 like "dozen" for 12?

I am not aware of any current or archaic English word for 24 other than the obvious combinations like "double dozen" or "score and four" ("score" is 20). German style ...
Conifold's user avatar
  • 74.8k
4 votes
Accepted

What is the origin of Arabic numerals

The problem with very old historical stuff including the origins of a certain concepts and giving due credit where it is due is one of the most difficult questions in history. The truth is that we may ...
AChem's user avatar
  • 4,049
2 votes

How was addition and multiplication of natural numbers defined before 1870 (Cantor and modern set theory)?

The addition and multiplication of numbers were seen as so intuitively obvious that no-one bothered to formalise them before the modern period with Peano's axioms and also the development of set ...
Mozibur Ullah's user avatar
2 votes
Accepted

How was addition and multiplication of natural numbers defined before 1870 (Cantor and modern set theory)?

In the first appendix (Note I) to his 1821 book Analyse Algebrique, Cauchy discusses multiplication of signs in detail, and then gives the following definition of addition: Ajouter au nombre A le ...
Mikhail Katz's user avatar
  • 5,421
2 votes

Was the concept of zero ever developed without relation to positional number systems?

According to wikipedia article on the Number 0, by 1740 BC, the Egyptians had a symbol for zero in accounting texts. The symbol nfr, meaning beautiful, was also used to indicate the base level in ...
AlainD's user avatar
  • 199
2 votes
Accepted

Was the concept of zero ever developed without relation to positional number systems?

The concept of zero (as a number) is not necessary for positional notation, one can do with a placeholder symbol, used like a punctuation mark, or even with just a blank space. This is exactly what ...
Conifold's user avatar
  • 74.8k
2 votes

What is the origin of Arabic numerals

The first 3 digits can be easily explained by the rapid tracing of strokes without lifting the writing stylus from the surface of the paper. If you look at the Chinese characters for 1, 2 and 3: 一, 二, ...
Leo's user avatar
  • 421
1 vote

Gate 44 at the Colosseum in Rome: XLIIII or XLIV? When and why the change?

When, was during the "Renaissance period, long after the fall of the Roman empire". Why is more difficult to ascertain. There are a number of speculative reasons. As you state, IIII was the ...
Fred's user avatar
  • 348
1 vote

Did anyone ever propose a hypercomplex numbers system with more than one anisotropic axis?

This won't be much of a "historical" answer (although my external links probably have interesting history in them), but hopefully it'll be mathematically useful, at least if construed as a ...
J.G.'s user avatar
  • 1,720
1 vote
Accepted

Who is the Dottie number named after?

The Dottie number is named in Samuel Kaplan's (2007) paper after the women who discovered it. The Dottie number was the nickname among my graduate school friends for the unique real root of cos(x) = ...
aitía's user avatar
  • 139
1 vote

What is the origin of Arabic numerals

You can see the origin of modern numerals and zero from Sanskrit, carved in granite, also at https://youtu.be/pElvQdcaGXE?t=101 in a Temple for zero in a talk by Marcus du Sautoy who looks at the ...
Partha Shakkottai's user avatar
1 vote

Was the concept of zero ever developed without relation to positional number systems?

It is well known that positional numeral systems are not possible without the concept of zero and corresponding notation. This is the necessary condition, but not sufficient one. This is wrong. See ...
Matthias's user avatar

Only top scored, non community-wiki answers of a minimum length are eligible