All Questions
Tagged with computability-theory algebraic-number-theory
6 questions
5
votes
0
answers
187
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Is there an effective way to compute the square root of an algebraic number?
For an algebraic number $\alpha$, let $f_\alpha$ denote its minimal polynomial. We can symbolically represent an algebraic number $\alpha$ by the tuple
$$
(f_\alpha, x, y, r) \in \mathbb{Q}[x] \times ...
16
votes
2
answers
1k
views
Is it decidable whether two real algebraic irrationals generate the same extension of the rationals?
For an algebraic number $\alpha$, let $f_\alpha$ denote its minimal polynomial. We can symbolically represent an algebraic number $\alpha$ by the tuple
$$
(f_\alpha, x, y, r) \in \mathbb{Q}[x] \times ...
0
votes
1
answer
126
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Integer quadratic representation subject to discriminant minimization algorithm
Let $f(x)=ax^2+bx+c$ and $f(x)=n$. Is there an algorithm to choose $a,b,c$ such that the discriminant is minimized? Where $a,b,c,n,x$ are all integers.
More concretely, is there an algorithm to find $...
4
votes
0
answers
249
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Coefficients in Hilbert's tenth problem over number rings: do they matter?
Here are two ways to define Hilbert's tenth problem over a ring $R$:
Given a polynomial $p \in \mathbb Z[x_1,\ldots,x_n]$, can one decide whether it has a solution in $R^n$?
Given a polynomial $p \in ...
4
votes
0
answers
242
views
Rational point oracle for smooth projective varieties
You have an oracle that decides if a smooth projective variety over $\mathbb{Q}$ has a $\mathbb{Q}$-point.
Can you then algorithmically decide if an arbitrary variety over $\mathbb{Q}$ has a $\mathbb{...
28
votes
0
answers
907
views
On certain representations of algebraic numbers in terms of trigonometric functions
Let's say that a real number has a simple trigonometric representation, if it can be represented as a product of zero or more rational powers of positive integers and zero or more (positive or ...