# International conference "Greedy approximation and related questions" ("Approximation and discretization")

The conference will be held from August 30 to September 3 in the Moscow hotel "Golden Ring", in the room "Serguiev Posad". 29 August is an arrival day, 4 September is a departure day.

We plan to have morning sessions (10.00-13.30, plenary talks for 50 minutes) and evening sessions (15.00-18.20, evening talks for 25 minutes).

Participant registration: on Monday, August 30, in the room "Serguiev Posad", from 9.00 to 9.50.

The sessions on Thursday, September 2, are dedicated to the 70th anniversary of the academician B.S. Kashin.

**Photos** (New!)

**Video** (New!)

Plenary talks:

S.V. Astashkin, P. Berna, P.A. Borodin, A.V. Dereventsov, R. DeVore, M.I. Dyachenko, G. Garrigos, G.A. Karagulyan, K. Kazarian, S.V. Konyagin, E. Kopecká, A.M. Olevskii, E.M. Semenov, M.A. Skopina, М.М. Skriganov, A.Yu. Shadrin, V.N. Temlyakov, S.Yu. Tikhonov.

Evening talks:

M.Sh. Burlutskaya, L.Sh. Burusheva, M.A. Chahkiev, V.V. Galatenko, S.L. Gogyan, B.I. Golubov, D.V. Gorbachev, M.G. Grigoryan, A.B. Kalmynin, E.D. Kosov, V.V. Lebedev, I.V. Limonova, S.Ya. Novikov, A.S. Orlova, M.G. Plotnikov, K.V. Runovskii, K.S. Ryutin, S.P. Sidorov, K.S. Shklyaev, P.A. Terekhin, A.I. Tyulenev, Al.R. Valiullin, Ar.R. Valiullin, M.A. Valov, K.S. Vishnevetskii.

Program (Moscow time):

August 30, Monday:

10.00, *V. Temlyakov*, "Greedy approximations in Banach spaces";

11.00, *A. Dereventsov*, "High-Dimensional Approximation via Smoothing-Based Gradient Free Optimization";

12.00–12.30, Coffee break

12.30, *S. Konyagin*, "On adaptive Fourier decomposition".

**Break**

15.00, *G. Garrigos (online)*, "Weak Chebyshev greedy algorithms";

16.00, *E. Kosov*, "Marcinkiewicz type problems for discretization of integral norms";

16.30–16.50, Coffee break

16.50, *Al. & Ar. Valiullins*, "Sharp sufficient condition for the convergence of greedy expansions with errors in coefficient computation";

17.20, *K. Vishnevetskii*, "On the coincidence of pure greedy and best m-term approximations";

17.50, *M. Valov*, "Conical orthogonal greedy algorithm".

August 31, Tuesday:

10.00, *M. Skopina*, "Around sampling-type approximation and Kotelnikov-Shannon formula";

11.00, *E. Semenov (online)*, "Orthogonal elements of rearrangement invariant spaces";

12.00–12.30, Coffee break

12.30, *P. Berna (online)*, "The bidemocracy in the world of greedy approximation".

**Break**

15.00, *S. Sidorov*, "Dual Estimates on Convergence Rate for Greedy Optimization Algorithms in Banach Spaces";

15.30, *P. Terekhin*, "Sequences of dilations and translations in function spaces";

16.00, *S. Novikov*, "Frames as dictionaries of sparse representations and their sparks";

16.30–16.50, Coffee break

16.50, *L. Burusheva*, "Refinement of the convergence rate of a greedy algorithm for special dictionaries";

17.20, *K. Shklyaev*, "Approximation by sums of shifts and dilations of a single function and ridge functions";

17.50, *A. Orlova*, "Convergence of weak orthogonal greedy approximations for one-element extensions of an orthogonal dictionary".

September 1, Wednesday:

10.00, *M. Dyachenko*, "Hardy-Littlewood theorem, Hardy transform and generalized piecewise monotone functions";

11.00, *S.Tikhonov*, "New estimates for the maximal functions";

12.00–12.30, Coffee break

12.30, *K. Kazarian*, "On Beurling's approximation theorem".

**Break**

15.00, *B. Golubov*, "Dyadic derivatives and integrals";

15.30, *M. Plotnikov*, "Capacities of positive measure sets and recovery of functions";

16.00, *K. Ryutin*, "Several problems of Compressed Sensing";

16.30–16.50, Coffee break

16.50, *V. Galatenko (online)*, "Convergence almost everywhere of orthorecursive expansions in Systems of Translates and Dilates";

17.20, *A. Kalmynin*, "Orthorecursive expansions of unity";

17.50, *A. Tyulenev*, "Some geometric properties of sets related to the \(d\)-Hausdorff content".

September 2, Thursday:

10.00, *P. Borodin*, "Selected Kashin theorems";

11.00, *A. Olevskii (online)*, "On one of the Luzin conjectures";

12.00–12.30, Coffee break

12.30, *M. Skriganov*, "Point distributions in the Hamming space";

**Break**

14.30–15.20, *G. Karagulyan*, "Orthogonal polynomials and Weyl multipliers";

15.30, *M. Grigoryan*, "Nonlinear approximation, Fourier coefficients and modifications of functions";

16.00, * V. Lebedev*, "Compact sets in the torus. Wiener Algebra and some other function spaces.
Extention operator";

16.30, *I. Limonova*, "Partition of a matrix into two submatrices with extremely small norm".

September 3, Friday:

10.00, *A. Shadrin*, "On stable reconstruction from Fourier samples";

11.00, *S. Astashkin*, "A new comparison method of norms in scales of function spaces";

12.00–12.30, Coffee break

12.30, *E. Kopecká (online)*, "Interplay of alternating projections and greedy approximation".

**Break**

15.00, *K. Runovskii*, "Approximation of periodic functions with high generalized smoothness by trigonometric polynomials";

15.30, *D. Gorbachev*, "Boundaries of the Nikolskii spherical \(\mathcal{L}_1\)-constants and \(L^p\)-approximation for \(p < 1\)";

16.00, *M. Burlutskaya*, "On divergent series in the Fourier method";

16.30–16.50, Coffee break

16.50, *M. Chahkiev*, "Exact value of the exponent convergence of the singular integral in Tarry's problem for homogeneous polynomials of degree \(n\) in two variables";

17.20, *S. Gogyan*, "Greedy algorithms in \(L_1\)";

17.50–18.40, *R. DeVore (online)*, "Thoughts on Deep Learning".

Organizing Committee:

→ V. Temlyakov (Chair)

→ P. Borodin (Deputy Chair)

→ A. Solodov (Deputy Chair)

→ V. Podolskii