Skip to main content

All Questions

0 votes
0 answers
16 views

AES S-box as simple algebraic transformation

The next matrix represents the Rijndael S-box according to wikipedia and other sources $$\begin{bmatrix}s_0\\s_1\\s_2\\s_3\\s_4\\s_5\\s_6\\s_7\end{bmatrix} = \begin{bmatrix} 1 & 0 & 0 &...
Keplerto's user avatar
  • 463
0 votes
0 answers
20 views

How to understand 'the problem of determining the exact number of monomials in P(x) given by a black box is #P-Complete'

In this paper:https://dl.acm.org/doi/pdf/10.1145/62212.62241, what's given is $P(x)$ a (sparse) multivariate polynomial with real(or complex) coefficients. The author claimed two things. It is known ...
Youzhe Heng's user avatar
1 vote
1 answer
32 views

Equivalent polynomials over a finite field

Disclamer. I'm not good at math, and the last time I did it in school was 10 years ago, so I'm writing everything in my own words. Suppose we are working with polynomials in the space of remainders ...
ddvamp's user avatar
  • 13
1 vote
0 answers
54 views

Does there exists something like the BKK Theorem for polynomials over finite fields?

I'm trying to count the number of common $\mathbb{F}_q^\times$-zeros of some polynomials $f,g \in \mathbb{F}_q[x,y]$. I thought I had a solution using the BKK theorem but I reread the theorem ...
Amelia Gibbs's user avatar
0 votes
1 answer
92 views

Extended euclidian algorithm

I'm trying to understand how the matrix form of the extended euclidian algorithm for polynomials works for a BCH code with coefficients from $GF(2^4)$ in https://en.wikipedia.org/wiki/BCH_code for ...
user159729's user avatar
2 votes
2 answers
85 views

In polynomial quotient rings over $\mathbb{F}_2$, how to use Chinese Remainder Theorem to solve equations?

Suppose I work over the polynomial quotient ring $\mathbb{F}_2[x,y]/\langle x^m+1,y^n+1\rangle$, and I want to solve for polynomials $s[x,y]$ that simultaneously solve the equations \begin{equation} a[...
JoJo P's user avatar
  • 133
1 vote
0 answers
86 views

Number of irreducible polynomials of degree at most n over a finite field

We know that the number $N(n,q)$ of irreducible polynomials of degree $n$ over the finite field $\mathbb{F}_q$ is given by Gauss’s formula $$N(n,q)=\frac{q-1}{n} \sum_{d\mid n}\mu(n/d)q^d.$$ The number ...
Hassen Chakroun's user avatar
1 vote
0 answers
29 views

Order of $\mathbb F _p [x] / (f)$.

I could use some help with the following exercise: Find the number of reducible monic polynomials of degree $2$ over $\mathbb F_p$. Show this implies that for every prime $p$ there exists a field of ...
RatherAmusing's user avatar
0 votes
0 answers
28 views

What's the point of the local zeta function?

I'm currently reading through Ireland and Rosen's "A Classical Introduction to Modern Number Theory", and I feel I'm missing the point of Chapter 11 on (local) zeta functions. When I see ...
Samuel Johnston's user avatar
0 votes
2 answers
82 views

Is this $f(x) = x^{6}+x^{5}+x^{4}+x^{3}+x^{2}+x+1$ irreducible in GF(5)?

Perhaps one can somehow apply Eisenstein's sign here by considering $f(x+1)$, but by default it is formulated for the expansion over $\mathbb{Q}$ of a polynomial from $\mathbb{Z}[x]$. Here we have $GF(...
mackenzie's user avatar
0 votes
1 answer
77 views

Show that GF(81) is an $x^{26}+x^{8}+x^{2}+1$ decomposition field

I tried decomposing the polynomial, but after taking out $(x^{2}+1)$ you have to break the remainder into polynomials of degree 4, which is manually hard. Perhaps this is solved by using Frobenius ...
mackenzie's user avatar
3 votes
0 answers
67 views

Is this connection between prime numbers, prime polynomials, and finite fields true?

I recently learned of the following connection between prime numbers and prime polynomials in the field of cardinality $2$. Namely, you take a natural number $n$, and use the digits of the base $2$ ...
user107952's user avatar
  • 21.4k
2 votes
1 answer
73 views

Why should a splitting field of a polynomial over $\mathbb{F}_p[X]$ be a cyclotomic extension?

I have just been doing a Galois theory exercise and one part of the exercise requires me to explain why, if $f \in \mathbb{F}_p[X]$ is a polynomial of degree $n$, its splitting field $L$ is a ...
Featherball's user avatar
0 votes
0 answers
54 views

When is $f = X^4 -1 \in \mathbb{F}_p[X], p $prime, irreducible and/or seperable? [duplicate]

I'm having some trouble figuring out a solution to this. I understand that $f$ is separable, iff all its roots are distinct, however I'm completely clueless about how to investigate that criterion......
Raiden's user avatar
  • 17
6 votes
2 answers
151 views

Irreducible polynomial in $\Bbb{Z}_2[x]$

Suppose $2k + 1 \equiv 3 \mod 4$ in $\Bbb{Z}_{\geq 1}$. Is the polynomial: $p_k(x) = x^{2k + 1} + x^{2k - 1} \dots + x + 1$ irreducible in $\Bbb{Z}_2[x]$? I do not know whether it is true or not... (...
Gamow Drop's user avatar

15 30 50 per page
1
2 3 4 5
54