Andrei Sipoș
Research Assistant @
TUD
Scientific Researcher @
IMAR
Building S2|15 (Mathebau), Room 225,
Fachbereich Mathematik, TU Darmstadt,
Schlossgartenstraße 7,
64289 Darmstadt,
Germany.
(
Curriculum Vitæ
,
arXiv
,
OPC
)
Employment
since Oct. 2017 — Research Assistant in the
Department of Mathematics
,
Technische Universität Darmstadt
.
since Oct. 2017 — Scientific Researcher at the
“Simion Stoilow” Institute of Mathematics of the Romanian Academy
(IMAR).
Nov. 2014 - Sep. 2017 — Research Assistant at IMAR.
Education
2017 — PhD in Mathematics,
Facultatea de Matematică și Informatică
(FMI),
University of Bucharest
(UB).
Advisor:
Laurențiu Leuștean
.
Thesis title:
Contributions to proof mining
.
2014 — MSc in Mathematics (Algebra and Number Theory), FMI, UB.
2012 — BSc in Computer Science, FMI, UB.
2012 — BSc in Mathematics, FMI, UB.
Papers
Publications
“Quantitative results on the Ishikawa iteration of Lipschitz pseudo-contractions”
(with
Laurențiu Leuștean
and Vlad Radu),
Journal of Nonlinear and Convex Analysis
, Volume 17, Number 11, 2277–2292, 2016
.
“Effective results on a fixed point algorithm for families of nonlinear mappings”
,
Annals of Pure and Applied Logic
, Volume 168, Issue 1, 112–128, 2017
.
“A note on the Mann iteration for $k$-strict pseudocontractions in Banach spaces”
,
Numerical Functional Analysis and Optimization
, Volume 38, Issue 1, 80–90, 2017
.
“Codensity and Stone spaces”
,
Mathematica Slovaca
, Volume 68, Issue 1, 57–70, 2018
.
“An application of proof mining to the proximal point algorithm in CAT(0) spaces”
(with
Laurențiu Leuștean
),
in:
A. Bellow, C. Calude, T. Zamfirescu (eds.),
Mathematics Almost Everywhere. In Memory of Solomon Marcus
(pp. 153–168), World Scientific, Singapore, 2018
.
“Effective strong convergence of the proximal point algorithm in CAT(0) spaces”
(with
Laurențiu Leuștean
),
Journal of Nonlinear and Variational Analysis
, Volume 2, Issue 2, 219–228, 2018
.
“An abstract proximal point algorithm”
(with
Laurențiu Leuștean
and Adriana Nicolae),
Journal of Global Optimization
, Volume 72, Issue 3, 553–577, 2018
.
“The asymptotic behaviour of convex combinations of firmly nonexpansive mappings”
,
arXiv:1802.08476 [math.OC], 2018. To appear in:
Journal of Convex Analysis
.
Preprints
“Proof mining in $L^p$ spaces”
,
arXiv:1609.02080 [math.LO], 2016. Submitted.
“The finitary content of sunny nonexpansive retractions”
(with
Ulrich Kohlenbach
),
arXiv:1812.04940 [math.FA], 2018. Submitted.
“Bounds on strong unicity for Chebyshev approximation with bounded coefficients”
,
arXiv:1904.10284 [math.CA], 2019. Submitted.
Talks
Codensity and Stone spaces
, at the
Eighth Congress of Romanian Mathematicians
, Iași, 2015.
Codensity and Stone spaces
, at
Logic Colloquium 2015
, Helsinki, 2015.
Proof mining and families of mappings
, at
PhDs in Logic VIII
, Darmstadt, 2016.
Effective results on algorithms using strict pseudocontractions
, during a scientific visit to
Universidad de Sevilla
, Spain, at the
IMUS
Analysis Seminar, Seville, 2016.
Proof mining and positive-bounded logic
, at
Logic Colloquium 2016
, Leeds, 2016.
Proof mining and positive-bounded logic
, at
Colloquium Logicum 2016
, Hamburg, 2016.
Proof mining in $L^p$ spaces
, during a scientific visit to
TU Darmstadt
, Germany, at the
TUD Logic Seminar
, Darmstadt, 2016.
Proof mining in convex optimization
, at
PhDs in Logic IX
, Bochum, 2017.
Representable functions in Moisil logic
, at
FROM 2017
, București, 2017.
Proof mining in convex optimization
, at
Logic Colloquium 2017
, Stockholm, 2017.
Playing with the logic of Moisil: nuances, games and representations
, at
BuCal 2017
, București, 2017.
Proof mining and the proximal point algorithm
, at
MFO Workshop no. 1745 (on Proof Theory and Constructive Mathematics)
, Oberwolfach, 2017.
Quantitative results on the method of averaged projections
, at the
Workshop on Proofs and Computation
(part of the
HIM Trimester Program on Types, Sets and Constructions
), Bonn, 2018.
Quantitative results on the method of averaged projections
, at
Logic Colloquium 2018
, Udine, 2018.
The finitary content of sunny nonexpansive retractions
, at
Days of Logic and Computability IV (Shanin-100)
, St. Petersburg, 2019.
The finitary content of sunny nonexpansive retractions
, at the
Ninth Congress of Romanian Mathematicians
, Galați, 2019.
The finitary content of sunny nonexpansive retractions
, at the
13th International Conference on Fixed Point Theory and its Applications
, Xinxiang, 2019.
The finitary content of sunny nonexpansive retractions
, at the
PCC (Proof, Computation, Complexity) 2019
, Djursholm, 2019.
Expository notes
Some notes on sheaf-theoretic model theory
.
An exposition of D. Ellerman's work from his PhD thesis.
Ultraproducts and uniform rates of asymptotic regularity and metastability
.
A detailed survey of J. Avigad and J. Iovino's results on the application of ultraproducts to quantifying results in nonlinear functional analysis.
Scientific Seminars
UB/IMAR Logic Seminar
TUD Doktorandentreff
Research Grants
January 2012 - May 2013: Member of the Grant
Universal Logic Methods for Computer Science
, CNCS Romania, PN-II-ID-PCE-2011-3-0439.
January 2015 - October 2016: Member of the Grant
Proof mining in metric analysis, geometric group theory and ergodic theory
, CNCS Romania, PN-II-ID-PCE-2011-3-0383.
October 2015 - September 2017: Member of the Grant
Modelling uncertainty in non-classical logics
, CNCS Romania, PN-II-RU-TE-2014-4-0730.
since April 2018: Member of DFG Project KO 1737/6-1 —
Proof Mining in Convex Optimization and Related Areas
.
Teaching
At TU Darmstadt
Introduction to Mathematical Logic, 3rd year exercise session, Winter Term 2017/2018 (
moodle link
), 2018/2019 (
moodle link
).
Applied Proof Theory, 1st Master's year exercise session, Summer Term 2017/2018.
At the University of Bucharest
Mathematical and Computational Logic, 1st year tutorial, Winter Term
2013/2014
,
2014/2015
, 2015/2016, 2016/2017.
Logic Programming, 2nd year lab and tutorial, Summer Term 2013/2014, 2014/2015, 2015/2016,
2016/2017
.
Declarative Programming, 3rd year lab, Winter Term 2014/2015.
Model Theory, 1st Master's year tutorial, Summer Term 2016/2017.