P vs NP completion problems
- Sep 2019
-
theconversation.com theconversation.com
- Jul 2019
-
mml-book.github.io mml-book.github.io
-
One major idea in mathematics is the idea of “closure”. This is the ques-tion: What is the set of all things that can result from my proposed oper-ations? In the case of vectors: What is the set of vectors that can result bystarting with a small set of vectors, and adding them to each other andscaling them? This results in a vector space
closure in mathematics. sounds similar to domain of a function
Tags
Annotators
URL
-
-
en.wikipedia.org en.wikipedia.org
-
In Hardy's words, "Exposition, criticism, appreciation, is work for second-rate minds. [...] It is a melancholy experience for a professional mathematician to find himself writing about mathematics. The function of a mathematician is to do something, to prove new theorems, to add to mathematics, and not to talk about what he or other mathematicians have done."
similar to Nassim Taleb's "History is written by losers"
Tags
Annotators
URL
-
- May 2019
-
www.businessinsider.com www.businessinsider.com
-
If you do the math
Here is the math: 2020-2023 4 years (Jan 1-Dec 31). 1 million annual is 4 million. That is way more than the 1.7 million
-
four
3 million vehicles divided by 4 years divided by 500,000 per factory makes less than two factories in my book.
-
- Mar 2019
-
sprott.physics.wisc.edu sprott.physics.wisc.edu
-
pi = 3.1415 ... e = 2.718 ... Euler's constant, gamma = 0.577215 ... = lim n -> infinity > (1 + 1/2 + 1/3 + 1/4 + ... + 1/n - ln(n)) (Not proven to be transcendental, but generally believed to be by mathematicians.) Catalan's constant, G = sum (-1)^k / (2k + 1 )^2 = 1 - 1/9 + 1/25 - 1/49 + ... (Not proven to be transcendental, but generally believed to be by mathematicians.) Liouville's number 0.110001000000000000000001000 ... which has a one in the 1st, 2nd, 6th, 24th, etc. places and zeros elsewhere. Chaitin's "constant", the probability that a random algorithm halts. (Noam Elkies of Harvard notes that not only is this number transcendental but it is also incomputable.) Chapernowne's number, 0.12345678910111213141516171819202122232425... This is constructed by concatenating the digits of the positive integers. (Can you see the pattern?) Special values of the zeta function, such as zeta (3). (Transcendental functions can usually be expected to give transcendental results at rational points.) ln(2). Hilbert's number, 2(sqrt 2 ). (This is called Hilbert's number because the proof of whether or not it is transcendental was one of Hilbert's famous problems. In fact, according to the Gelfond-Schneider theorem, any number of the form ab is transcendental where a and b are algebraic (a ne 0, a ne 1 ) and b is not a rational number. Many trigonometric or hyperbolic functions of non-zero algebraic numbers are transcendental.) epi pie (Not proven to be transcendental, but generally believed to be by mathematicians.) Morse-Thue's number, 0.01101001 ... ii = 0.207879576... (Here i is the imaginary number sqrt(-1). Isn't this a real beauty? How many people have actually considered rasing i to the i power? If a is algebraic and b is algebraic but irrational then ab is transcendental. Since i is algebraic but irrational, the theorem applies. Note also: ii is equal to e(- pi / 2 ) and several other values. Consider ii = e(i log i ) = e( i times i pi / 2 ) . Since log is multivalued, there are other possible values for ii. Here is how you can compute the value of ii = 0.207879576... 1. Since e^(ix) = Cos x + i Sin x, then let x = Pi/2. 2. Then e^(iPi/2) = i = Cos Pi/2 + i Sin Pi/2; since Cos Pi/2 = Cos 90 deg. = 0. But Sin 90 = 1 and i Sin 90 deg. = (i)*(1) = i. 3. Therefore e^(iPi/2) = i. 4. Take the ith power of both sides, the right side being i^i and the left side = [e^(iPi/2)]^i = e^(-Pi/2). 5. Therefore i^i = e^(-Pi/2) = .207879576... Feigenbaum numbers, e.g. 4.669 ... . (These are related to properties of dynamical systems with period-doubling. The ratio of successive differences between period-doubling bifurcation parameters approaches the number 4.669 ... , and it has been discovered in many physical systems before they enter the chaotic regime. It has not been proven to be transcendental, but is generally believed to be.)
Tags
Annotators
URL
-
- Jan 2019
-
en.wikipedia.org en.wikipedia.org
-
A rooted binary tree is full if every vertex has either two children or no children.
Example of Catalan Numbers use case.
Tags
Annotators
URL
-
-
en.wikipedia.org en.wikipedia.org
-
Catalan numbers notation and short explanation of it.
Use - LookUP: Combinatorics (non crossing combinations) ex: ((())), ()(()), ()()(), (())(), (()())
ref: https://www.geeksforgeeks.org/program-nth-catalan-number/
-
- Dec 2018
-
www.npr.org www.npr.org
-
computer owned by Patrick Laroche of Ocala, Fla., discovered the number on Dec. 7,
Newest Mersenne Prime was discovered in Ocala, FL, very close to us.
Interesting tidbit :)
-
- Nov 2018
-
www.coursera.org www.coursera.org
-
Basic Statistics
part of specialization
Tags
Annotators
URL
-
-
www.coursera.org www.coursera.org
-
Mathematics for Machine Learning
specialization
-
-
meduza.io meduza.io
-
Начните с нескольких основных книг, которые изменят ваши представления о математикеЛучше всего «ставит голову» книга «Начала теории множеств» Николая Верещагина и Александра Шеня. Она даст основу для понимания (а в дальнейшем и самостоятельного построения!) логических рассуждений. С нее же начнется и понимание теории множеств, лежащей в основе современной математики.Охватить больше разделов математики поможет книга Рихарда Куранта и Герберта Роббинса «Что такое математика?». Как и книгу Верещагина и Шеня, эту книгу нужно читать внимательно, делая все упражнения. Если первые две книги окажутся сложными, можете начать с моей «Математики для гуманитариев». Ее также следует читать с самого начала, страницу за страницей, не стоит браться за чтение с середины. Она не очень простая, но предварительных сведений и математической культуры не предполагает.Чтобы понять, каким образом математика входит в нашу жизнь, можно прочитать «Кому нужна математика?» Андрея Райгородского и Нелли Литвак или «Математическую составляющую» (сборник сюжетов под редакцией Николая Андреева).
nice books
-
- Sep 2018
-
blog.emacsen.net blog.emacsen.net
-
Learning Math Earlier With Computers
-
- Apr 2018
-
www.tandfonline.com www.tandfonline.com
-
we found advanced math and science courses advertised but not actually offered and specialized STEM programs eroded or discontinued within a few years of inception.
Some interesting data points in this article.
-
-
www.edweek.org www.edweek.org
-
Yet, across the country, 2 in 5 high schools don't offer physics, according to an Education Week Research Center analysis of data from the U.S. Department of Education's office for civil rights.
How widely known is this figure?
-
-
-
n this note we determine thetorsion subgroup of the additive group of (1.1) in the case whereLhas rank 2, thatisXis a set of two elements, andcis a prime number
Wow!
Tags
Annotators
URL
-
-
link.springer.com link.springer.com
-
Of particular interest are the lower central series: G1=GG1=GG_1 =G, Gi+1=[Gi,G]Gi+1=[Gi,G]G_{i+1} = [G_i, G], i≥1i≥1i \ge 1, and, for a fixed prime number p, the Zassenhaus series (see [7, 8]).
This is interesting.
-
-
www.exploratorium.edu www.exploratorium.edu
-
Leonhard Euler, who adopted it in 1737
Actually, he first used π in 1727, and it meant 6.28.., not 3.14..
Tags
Annotators
URL
-
- Mar 2018
-
www.wias-berlin.de www.wias-berlin.de
-
- Gummel mapping/method
- the part about machine-executed proofs sounds like https://media.ccc.de/v/34c3-9105-coming_soon_machine-checked_mathematical_proofs_in_everyday_software_and_hardware_development
- "semantic TeX" => CTAN package?
- OMDoc
- sTeX
- MMT
- TGView
- MPD Viewer
- OpenDreamKit = domain-specific language?
- MaMoReD
Tags
Annotators
URL
-
-
www.wias-berlin.de www.wias-berlin.de
-
- R/(gg)plots visualise => linguists detect interesting phenomena to analyse further
- Wang2Vec: train backprogagation network
Tags
Annotators
URL
-
- Feb 2018
-
yt-project.github.io yt-project.github.io
-
Let’s use some common units as examples: gram (g), erg (erg), and solar mass per cubic megaparsec (Msun / Mpc33^3). g is an atomic, CGS base unit, erg is an atomic unit in CGS, but is not a base unit, and Msun/Mpc33^3 is a combination of atomic units, which are not in CGS, and one of them even has an SI prefix. The dimensions of g are mass and the cgs factor is 1. The dimensions of erg are mass * length$^2$ * time−2−2^{-2} and the cgs factor is 1. The dimensions of Msun/Mpc33^3 are mass / length33^3 and the cgs factor is about 6.8e-41.
Tags
Annotators
URL
-
- Jul 2017
-
www.degruyter.com www.degruyter.com
-
satisfy the two usual distributive laws. Singlesemirings as well as classes of semirings form important structures in Automataand Formal Languages Theories [5
Like so.
-
- May 2017
-
coolwanglu.github.io coolwanglu.github.io
-
1st order Eulerian numbers:Permutations
Annotate math with math!
$$\varepsilon = \frac{2}{h^3} \int_0^{p_F} \sqrt{p^2 c^2 + m^2 c^4} \cdot 4 \pi p^2 dp=$$
$$\frac{8 \pi}{h^3} \frac{m c^2}{\lambda^3} \int_0^x \sqrt{1+y^2} \cdot y^2 dy $$
Tags
Annotators
URL
-
-
www.annualreviews.org www.annualreviews.org
-
The first review, by C. Hendricks Brown et al., poses the issues raised by the growingrecognition
$$\varepsilon = \frac{2}{h^3} \int_0^{p_F} \sqrt{p^2 c^2 + m^2 c^4} \cdot 4 \pi p^2 dp=$$
$$\frac{8 \pi}{h^3} \frac{m c^2}{\lambda^3} \int_0^x \sqrt{1+y^2} \cdot y^2 dy$$
-
- Apr 2017
-
www.cogentoa.com www.cogentoa.com
-
For detailed study of various properties, generalization and application of Wrightfunction and generalized Wright function,
-
- Jan 2017
-
betterexplained.com betterexplained.com
-
Whether you're a student, parent, or teacher, this book is your key to unlocking the aha! moments that make math click -- and learning enjoyable.
You had me already at the Coffee Cup picture over the equations! :)
-
-
academic.evergreen.edu academic.evergreen.edu
-
LSB (least significant bit): The rightmost bit MSB (most significant bit): The leftmost bit
This only applies to Little-endian architecture. Big-endian is reversed.
-
- Nov 2016
-
www.knewton.com www.knewton.com
-
x2
maybe it should be \(x^3\)
-
- Oct 2016
-
bullshit.ist bullshit.ist
-
Sunil Singh asks us to stop promoting mathematics based on its current applications in business and science. Math is an art that should be enjoyed for its own sake.
This reminded me of A Mathematician's Lament by Paul Lockhart. This is a 25-page essay which was later worked into a 140-page book. (And Sunil Singh has read at least one of them. He credits Lockhart in one of the replies.)
It also reminds me of this article on the history of Gaussian elimination and the birth of matrix algebra. Newton's algebra text included instructions for solving systems of equations -- but it didn't have much practical use until later. (Silly word problems are as old as mathematics.)
-
- Sep 2016
-
en.wikipedia.org en.wikipedia.org
-
A forest is just a collection of trees. The main difference is that a forest does not necessarily need to be connected.
-
- Jul 2016
-
www.quantamagazine.org www.quantamagazine.org
-
hyperuniform distribution - Appears random at smaller scales, but more predictable at larger scales.
-
-
steinhardt.nyu.edu steinhardt.nyu.edu
-
The first set, called Math Instructional, was for apps that would make math relevant for students by linking it to their lives and enabling students at different ability levels to work together
This has real potential because of the research base that supports the instructional approach.
-
- Mar 2016
-
www.quantamagazine.org www.quantamagazine.org
-
New property of prime numbers discovered. Primes greater than 5 can end with 1, 3, 7, or 9. The next prime is less likely to end with the same digit, and biased toward one of the remaining three. For instance, a prime ending in 3 is most likely to be followed by a prime ending in 9. The bias evens out as the primes get larger, but only very slowly.
-
- Feb 2016
-
www.math-cs.gordon.edu www.math-cs.gordon.edu
-
Number Theory: In Context and Interactive, Karl-Dieter Crisman (online textbook)
-
-
linear.pugetsound.edu linear.pugetsound.edu
-
A First Course in Linear Algebra, Robert A. Beezer<br> Free as PDF or online.
Tags
Annotators
URL
-
-
www.complexityexplorer.org www.complexityexplorer.org
-
Free courses and tutorials from the Santa Fe Institute on subjects related to complex systems science.
-
- Jan 2016
-
blogs.scientificamerican.com blogs.scientificamerican.com
-
P(B|E) = P(B) X P(E|B) / P(E), with P standing for probability, B for belief and E for evidence. P(B) is the probability that B is true, and P(E) is the probability that E is true. P(B|E) means the probability of B if E is true, and P(E|B) is the probability of E if B is true.
-
The probability that a belief is true given new evidence equals the probability that the belief is true regardless of that evidence times the probability that the evidence is true given that the belief is true divided by the probability that the evidence is true regardless of whether the belief is true. Got that?
-
-
www.gutenberg.org www.gutenberg.org
-
I would like to see an accurate array of photographs of these tasty lunch options. What does a a "Princess Sandwich" even look like? Is a "Celery Sandwich" satisfying? I'd be pleased to see precise measurements of the ideal "Tea Biscuit" Sandwich.
-
-
category-theory.mitpress.mit.edu category-theory.mitpress.mit.edu
-
Category Theory for the Sciences by David I. Spivak<br> Creative Commons Attribution-NonCommercial-ShareAlike 4.0<br> MIT Press.
-
-
-
Open source textbooks approved by the American Institute of Mathematics.
Tags
Annotators
URL
-
- Mar 2015
-
arxiv.org arxiv.org
-
θ dμ ≥ p 16 π | Σ |
Qual a relação dessa desigualdade com a dita desigualdade de Penrose Riemanniana provada por Huisken-Ilmanen e Bray?
-
GIBBONS-PENROSE INEQUALITY
Qual a relação dessa desigualdade com a dita desigualdade de Penrose Riemanniana provada por Huisken-Ilmanen e Bray?
-
θ dμ ≥ p 16 π | Σ |
Isso significa que a taxa expansão nula futura (para fora) \( \theta \) é no mínimo $$ \sqrt{16 \pi |\Sigma|} $$
-
- Jan 2015
-
mathinsight.org mathinsight.org
-
A function like f(x,y)=x+y is a function of two variables. It takes an element of R2, like (2,1), and gives a value that is a real number (i.e., an element of R), like f(2,1)=3. Since f maps R2 to R, we write f:R2→R. We can also use this “mapping” notation to define the actual function. We could define the above f(x,y) by writing f:(x,y)↦x+y. To contrast a simple real number with a vector, we refer to the real number as a scalar. Hence, we can refer to f:R2→R as a scalar-valued function of two variables or even just say it is a real-valued function of two variables. Everything works the same for scalar valued functions of three or more variables. For example, f(x,y,z), which we can write f:R3→R, is a scalar-valued function of three variables.
f:R^2 \rightarrow R demek f(x,y)=z | Skalar-Değerli f f:R \rightarrow R^2 demek f(x)=(y,z) | VektörelDeğ f
-
f:R→R as a shorthand way of expressing that f is a function from R onto R.
Tags
Annotators
URL
-
- Sep 2013
-
en.wikipedia.org en.wikipedia.org
-
A computable Dedekind cut is a computable function which when provided with a rational number as input returns or ,
This definition of computable Dedekind cut is wrong. The correct definition is that the lower and the upper cut be computably enumerable.
Tags
Annotators
URL
-