New posts in abstract-algebra

Adjunctions are Kan Extensions.

If ideal quotients of a ring are isomorphic, are these ideals isomorphic?

Normalizer of a Sylow 2-subgroups of dihedral groups

Splitting field implies Galois extension

prove that $\mathbb{C}$ and $\mathbb{R}$ are not isomorphic as rings

What is the significance of multiplication (as distinct from addition) in algebra & ring theory?

Characteristic of a simple ring is either prime or $0$

Primes of form $a^2 + 24b^2$

Is every commutative ring having the invariant basis number property equivalent to AC?

Any element of $\mathbf{Z}[\xi]$ is congruent to an integer modulo $(1-\xi)^2$ if multiplied by a suitable power of $\xi$

Graphically Organizing the Interrelationships of Basic Algebraic Structures

Prove every group of order less or equal to five is abelian [closed]

Showing $K[u]$ is a field when $u$ is algebraic over $K$.

If M+N and M$\cap$N are finitely generated modules, so are M and N.

Understanding of exterior algebra

Finitely generated projective modules are isomorphic to their double dual.

$2 \otimes_{R} 2 + x \otimes_{R} x$ is not a simple tensor in $I \otimes_R I$

Elements of $S_n$ can be written as a product of $k$-cycles.

Why is the quotient map $SL_n(\mathbb{Z})$ to $SL_n(\mathbb{Z}/p\mathbb Z)$ is surjective?

Minimal polynomial of $\zeta+\zeta^{-1}$