Are the irrationals + zero an additive group?
158368
Irrationals: A Group?
113572
Are all multiplicative functions additive?
92298
The additive group $\mathbb{G}_a$ over an infinite field $k$ is not a topological group
22408
Jutifying: irrational + rational = irrational
122914
An integer $n$, such that $nx = 0$, where $x$ belongs to the quotient group $\Bbb Q/\Bbb Z$
20315
$\sqrt[31]{12} +\sqrt[12]{31}$ is irrational
81150
Positive integer multiples of an irrational mod 1 are dense
26394
Is the sum and difference of two irrationals always irrational?
151876
Is irrational times rational always irrational?
22783
Is the set $Z_n = \{ 0, 1, . . . , n-1 \}$ for $n ≥ 1$ is a group under addition modulo n?
53945
The square root of a prime number is irrational
126513
Automorphism of the group of rational numbers under addition
88645
Prove that the additive groups $\mathbb{R}$ and $\mathbb{Q}$ are not isomorphic.
120401
Does there exist a pair of infinite fields, the additive group of one isomorphic to the multiplicative group of the other?
129433
$\sqrt{m_1}+\sqrt{m_2}+ \cdots + \sqrt{m_n}$ is Irrational
42444
Irrationality of $\sum_{p\in\mathbb{P}} \frac{1}{2^{p}}$
13550
For an irrational number $\alpha$, prove that the set $\{a+b\alpha: a,b\in \mathbb{Z}\}$ is dense in $\mathbb R$