Is there a characterization of modules (AND equivalent characterizations of rings R) over integral domains R with the property that each left ideal in R is flat?When all left ideals are projective,then we have Dedekind domains,right?
2026-04-02 00:57:33.1775091453
ideal,ring,flat module,modules over R
191 Views Asked by Bumbble Comm https://math.techqa.club/user/bumbble-comm/detail At
1
There are 1 best solutions below
Related Questions in RING-THEORY
- Jacobson radical = nilradical iff every open set of $\text{Spec}A$ contains a closed point.
- A commutative ring is prime if and only if it is a domain.
- Find gcd and invertible elements of a ring.
- Prove that $R[x]$ is an integral domain if and only if $R$ is an integral domain.
- Prove that $Z[i]/(5)$ is not a field. Check proof?
- If $P$ is a prime ideal of $R[x;\delta]$ such as $P\cap R=\{0\}$, is $P(Q[x;\delta])$ also prime?
- Let $R$ be a simple ring having a minimal left ideal $L$. Then every simple $R$-module is isomorphic to $L$.
- A quotient of a polynomial ring
- Does a ring isomorphism between two $F$-algebras must be a $F$-linear transformation
- Prove that a ring of fractions is a local ring
Related Questions in MODULES
- Idea to make tensor product of two module a module structure
- $(2,1+\sqrt{-5}) \not \cong \mathbb{Z}[\sqrt{-5}]$ as $\mathbb{Z}[\sqrt{-5}]$-module
- Example of simple modules
- $R$ a domain subset of a field $K$. $I\trianglelefteq R$, show $I$ is a projective $R$-module
- $S_3$ action on the splitting field of $\mathbb{Q}[x]/(x^3 - x - 1)$
- idempotent in quiver theory
- Isomorphism of irreducible R-modules
- projective module which is a submodule of a finitely generated free module
- Exercise 15.10 in Cox's Book (first part)
- direct sum of injective hull of two modules is equal to the injective hull of direct sum of those modules
Related Questions in IDEALS
- Prime Ideals in Subrings
- Ideals of $k[[x,y]]$
- Product of Ideals?
- Let $L$ be a left ideal of a ring R such that $ RL \neq 0$. Then $L$ is simple as an R-module if and only if $L$ is a minimal left ideal?
- Show $\varphi:R/I\to R/J$ is a well-defined ring homomorphism
- A question on the group algebra
- The radical of the algebra $ A = T_n(F)$ is $N$, the set of all strictly upper triangular matrices.
- Prove that $\langle 2,1+\sqrt{-5} \rangle ^ 2 \subseteq \langle 2 \rangle$
- $\mathbb{Z}[i] / (2+3i)$ has 13 elements
- Ideal $I_p$ in $\mathbb{F}_l[x]/(x^p -1)$ where $\frac{\epsilon p}{2} \leq \dim(I_p) < \epsilon p$
Trending Questions
- Induction on the number of equations
- How to convince a math teacher of this simple and obvious fact?
- Find $E[XY|Y+Z=1 ]$
- Refuting the Anti-Cantor Cranks
- What are imaginary numbers?
- Determine the adjoint of $\tilde Q(x)$ for $\tilde Q(x)u:=(Qu)(x)$ where $Q:U→L^2(Ω,ℝ^d$ is a Hilbert-Schmidt operator and $U$ is a Hilbert space
- Why does this innovative method of subtraction from a third grader always work?
- How do we know that the number $1$ is not equal to the number $-1$?
- What are the Implications of having VΩ as a model for a theory?
- Defining a Galois Field based on primitive element versus polynomial?
- Can't find the relationship between two columns of numbers. Please Help
- Is computer science a branch of mathematics?
- Is there a bijection of $\mathbb{R}^n$ with itself such that the forward map is connected but the inverse is not?
- Identification of a quadrilateral as a trapezoid, rectangle, or square
- Generator of inertia group in function field extension
Popular # Hahtags
second-order-logic
numerical-methods
puzzle
logic
probability
number-theory
winding-number
real-analysis
integration
calculus
complex-analysis
sequences-and-series
proof-writing
set-theory
functions
homotopy-theory
elementary-number-theory
ordinary-differential-equations
circles
derivatives
game-theory
definite-integrals
elementary-set-theory
limits
multivariable-calculus
geometry
algebraic-number-theory
proof-verification
partial-derivative
algebra-precalculus
Popular Questions
- What is the integral of 1/x?
- How many squares actually ARE in this picture? Is this a trick question with no right answer?
- Is a matrix multiplied with its transpose something special?
- What is the difference between independent and mutually exclusive events?
- Visually stunning math concepts which are easy to explain
- taylor series of $\ln(1+x)$?
- How to tell if a set of vectors spans a space?
- Calculus question taking derivative to find horizontal tangent line
- How to determine if a function is one-to-one?
- Determine if vectors are linearly independent
- What does it mean to have a determinant equal to zero?
- Is this Batman equation for real?
- How to find perpendicular vector to another vector?
- How to find mean and median from histogram
- How many sides does a circle have?
You're sending some mixed signals here by referring to things which are often considered commutative (integral domains and Dedekind domains) and also referring to left modules. I'll do my best to address everything.
It's true that a commutative domain is Dedekind if and only if all of its ideals are projective, and that a commutative domain is Prufer if and only if all ideals are flat.
For noncommutative rings, a ring in which all left ideals are projective is called a left hereditary ring. If it's a domain it's just called a left hereditary domain. This turns out to be equivalent to the category of left $R$ modules being "hereditarily projective" in the sense that submodules of projective modules are projective.
Some people have found additional conditions to add in order to justify noncommutative definitions of Dedekind domains, but I don't know them well enough to comment.
Among noncommutative rings, I don't think I've run across a special name for rings with all left ideals flat, but it's well known that it is equivalent to the category of left modules for the ring being "hereditarily flat," by which I mean that submodules of flat left modules are flat. Again, as mentioned above, this condition on a commutative domain is the same thing as a Prufer domain.
A weaker notion of "left hereditary" is "left semihereditary" where we only require the finitely generated left ideals of the ring to be flat. Among commutative domains, this is equivalent to being Prufer, but for noncommutative rings I haven't seen anything that leads me to believe that "all left ideals flat" is the same as "left semihereditary." I think left semihereditary rings have the property that left ideals are flat, though.