Ali Taghavi

Ali Taghavi
Qom University Of Technology

PHD

About

17
Publications
10,612
Reads
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12
Citations
Additional affiliations
September 2014 - September 2014
Institut de Recherches Mathematiques Avancée
Institut de Recherches Mathematiques Avancée
Position
  • A short vist
Description
  • I presented a talk at IRMA, entitled: "What theories can be related to limit cycle theory" My talk was based on the second partof this note; http://arxiv.org/abs/1302.0001
September 2006 - December 2020
Damghan University
Position
  • Professor (Assistant)
Description
  • Some Graduate courses I have taught: Operator theory, Algebraic Topology, Differentiable Manifold, K-theory, Real Analysis. Functional Analysis.
September 1999 - June 2000
University of Burgundy
Position
  • Visiting researcher(As a PHD student)
Education
September 1996 - September 2002
Sharif University of Technology
Field of study
  • Mathematics, Dynamical system

Publications

Publications (17)
Article
Full-text available
In this paper we give an alternative proof for a vanishing result about flat functions proved in G.Stoica, "When must a flat function be identically zero", The American Mathematical Monthly 125(7)648-649, 2018. With a dynamical approach we give a generalization of this result to multidimensional variables.
Preprint
Full-text available
In this paper we give an alternative proof for a vanishing result about flat functions proved in G.Stoica, "When must a flat function be identically zero", The American Mathematical Monthly 125(7)648-649,2018. With a dynamical approach we give a generalization of this result to multidimensional variables.
Data
My teaching statement
Preprint
Full-text available
We give a counter example to the MO question below. Despite of two MO bounties on this question, it was unanswered for more than 1 year https://mathoverflow.net/questions/293197/a-complex-limit-cycle-not-intersecting-the-real-plane
Research
Full-text available
Bulletin of Iran. math Society Vol 42 (2016) No 5 pp. 1169-1177
Article
Full-text available
Using characteristic classes, we give an alternative proof for the fixed point property of CP2n
Article
Let $A$ be a $C^{*}$ algebra and $T: A\rightarrow A$ be a symmetric linear map which satisfies in functional equation $T(x)T(y)=T^{2}(xy)$. We prove that under each of the following conditions, $T$ must be the trivial map $T(x)=\lambda x$ for some $\lambda \in \mathbb{R}: $A$ is a simple $C^{*}$-algebra. $A$ is unital with trivial center and has a...
Article
We study some properies of $Z^{*}$ algebras, thos C^* algebra which all positive elements are zero divisors. We show by means of an example that an extension of a Z* algebra by a Z* algebra is not necessarily Z* algebra. However we prove that an extension of a non Z* algebra by a non Z* algebra is again a Z^* algebra. As an application of our metho...
Article
Full-text available
A consequence of the Gauss Bonnet theorem is interpreted in term of operator theory by Alain Connes in his book, Non Commutative geometry. In this note we explain in details about his method. We also introduce an operator theoretical nature for limit cycle theory.
Article
In this paper we concern with positive zero divisors in $C^{*}$ algebras. By means of zero divisors, we introduce a hereditary invariant for $C^{*}$ algebras. Using this invariant, we give an example of a $C^{*}$ algebra $A$ and a $C^{*}$ sub algebra $B$ of $A$ such that there is no a hereditary imbedding of $B$ into $A$. We also introduce a new co...
Article
Full-text available
Using methods from the theory of commutative graded Banach algebras, we obtain a generalization of the two dimensional Borsuk-Ulam theorem as follows: Let $\phi:S^{2} \rightarrow S^{2}$ be a homeomorphism of order n and $\lambda\neq 1$ be an nth root of the unity, then for every complex valued continuous function $f$ on $S^{2}$ the function $\sum_{...
Article
Full-text available
We present some questions and suggestion on the second part of the Hilbert 16th problem
Article
Using Singular Rescaling We Prove Some Bifurcation Results. This note Presents short proofs for some Bifurcation results which had been appeared with other Authors
Article
We prove that coexistence of two limit cycles with disjoint interior can not occur in certain quadratic systems
Article
Full-text available
We Prove That The Uniform Upper Bound for the Number Of Limit Cycles Of The Lienard Equation of Degree 4 Can not be equals to 2. Further We Suggest to Embedding Planar Lienard Equations In Higher Dimension and Present question of completly integrabiolity of Corresponding Hamiltonians. Actually this Question Suggest To Look at to Limit Cycles Proble...
Article
Problem asks for a uniform upper bound H(n) for the number of limit cycles of a polynomial vector field X of degree n on the Plane. More ever it seems that ”limit cycles ” are The only obstructions for solving the ”PDE ” X.g = f, globally in the plane The following observation about Lienard equation suggests to look at the Hilbert 16th problem as a...
Article
Full-text available
It is conjectured by Pugh, Lins and de Melo in (7) that the system of equations ( ú x = y − F(x) ú y = −x

Questions

Questions (53)
Question
Dear colleagues.
In the following question i try to extend the concept of characters in group theory to a wilder class of functions. A character on a group G is a group homomorphism $\phi:G \to S^1$.
For every character $\phi=X+iY$ on a group $G$, we have $Cov(X.Y)=0$.
This is a motivation to consider all $\phi=X+iY: G\to S^1$ with $Cov(X,Y)=0$.
Please see this post:
So this question can be a starting point to translate some concepts in geometric group theory or theory of bamenability of groups in terms of notations and terminologies in statistics and probability theory.
Do you have any ideas, suggestions or comments?
Thank you
Question
Dear colleagues,
I would appreciate if you give comment on the following question:
In this question, the components of a vector field satisfy certain partial differential equation. then we guess that under this condition the vector field can not have any limit cycle:
Thank you for your attention

Projects

Project (1)
Project
In this project we search for some new interpretations for concept "limit cycle". Limit cycles are the main object of the second part of the Hilbert 16th problem. In foliation terminology, a limit cycle is a compact leaf of a one dimensional foliation ofa surface whose holonomy is different from the identity map. Some questions in this directions: https://mathoverflow.net/questions/219638/proposals-for-polymath-projects/264440#264440 http://mathoverflow.net/questions/160945/limit-cycles-as-closed-geodesicsin-negatively-curved-space http://mathoverflow.net/questions/164059/codimension-of-the-range-of-certain-linear-operators https://www.researchgate.net/deref/https%3A%2F%2Fmathoverflow.net%2Fquestions%2F335820%2Fa-cohomology-associated-to-a-not-necessarily-integrable-distribution-hilbert