Education:
Ph.D., Mathematics, Brown University
M.Sc., Mathematics, Brown University
B.Sc., Mathematics, University of Cyprus
Research Interests:
Partial differential equations of mixed type; nonlinear hyperbolic conservation laws; kinetic theory; nonlinear diffusive-dispersive equations; differential geometry
Courses Taught at WVU:
Math 758. Theory of Partial Differential Equations 2
Math 757. Theory of Partial Differential Equations 1
Math 651. Real Variables 2
Math 568. Advanced Calculus
Math 567. Advanced Calculus
Math 566. Intermediate Partial Differential Equations
Math 560. Introduction to Dynamical Systems and Applications
Math 555. Complex Variables 1
Math 551. Real Variables 1
Math 465. Partial Differential Equations
Math 460. Introduction to Dynamical Systems and Applications
Math 456. Complex Variables
Math 451. Introduction to Real Analysis 1
Math 441. Applied Linear Algebra
Math 375. Applied Modern Algebra
Math 261. Elementary Differential Equations
Math 251. Multivariable Calculus
Math 155. Calculus 1
Math/DSCI 191. First-Year Seminar
Recent Publications:
Solving the Wave Equation on Discrete Time Scales, Davis Funk and Charis Tsikkou, (2025). To appear in Involve – a journal of Mathematics
An analysis of a 2×2 Keyfitz–Kranzer type balance system with varying generalized Chaplygin gas, Jack Frew, Nigel Keyser, Ethan Kim, Griffin Paddock, Camden Toumbleston, Sara Wilson and Charis Tsikkou, Physics of Fluids, 36 (2024), 096132
Radially symmetric non-isentropic Euler flows: Continuous blowup with positive pressure, Helge Kristian Jenssen and Charis Tsikkou, Physics of Fluids, 35 (2023), 016117
Amplitude Blowup in Radial Isentropic Euler Flow, Helge Kristian Jenssen and Charis
Tsikkou, SIAM Journal on Applied Mathematics, 80 (2020), no. 6, 2472-2495. MR4181105
Multi-d isothermal Euler flow: existence of unbounded radial similarity solutions, Helge Kristian Jenssen and Charis Tsikkou, Physica D. Nonlinear Phenomena, 410 (2020), 132511, 14 pp. MR4091348
On similarity flows for the compressible Euler system, Helge Kristian Jenssen and Charis Tsikkou, Journal of Mathematical Physics, 59 (2018), no. 12, 121507, 25. pp. MR3894017
Riemann Problems for the Nonlinear Wave System: Rarefaction Wave Interactions, Eun Heui Kim and Charis Tsikkou, Discrete and Continuous Dynamical Systems, 37 (2017), no. 12, 6257-6289. MR3690303
Radial solutions to the Cauchy problem for $\square_{1+3}U=0$ as limits of exterior solutions, Helge Kristian Jenssen and Charis Tsikkou, Journal of Hyperbolic Differential Equations, 13 (2016), no. 4, 833-860. MR3593709
Grants:
(with Adam Halasz, Casian Pantea, Adrian Tudorascu) NSF, DMS - 2417985, Applied Mathematics. Conference: The 42nd Southeastern-Atlantic Regional Conference on Differential Equations. Principal Investigator. July 1, 2024 - June 30, 2025. Amount: $30,000
(Adrian Tudorascu as Senior Personnel) NSF, DMS - 2349040, REU Site: Undergraduate Research in Applied Analysis at West Virginia University. Principal Investigator. April 1, 2024 - March 31, 2027. Amount: $ 371,990.
(with Qingtian Zhang and Adrian Tudorascu) NSF, DMS - 2309801, Applied Mathematics. Conference: Systems of PDEs in Fluid Mechanics and Atmospheric Sciences. Co-Principal Investigator. August 1, 2023 - July 31, 2025. Amount: $29,996
(with Casian Pantea) Mathematical Association of America's Dolciani Mathematics Enrichment Grant Program. Title: West Virginia University Junior Math Club. Co-Principal Investigator. May 1, 2021 - May 9, 2025. Amount: $5,000
NSF, DMS - 1714912, Applied Mathematics. Title: Solutions of Nonlinear Hyperbolic
and Mixed Type Partial Differential Equations. Principal Investigator. July 15,
2017 - June 30, 2022. Amount: $141,000
(with Casian Pantea) WVU Internal Grants Program, Community Engagement. Title: WVU Junior Math Club. Co-Principal Investigator. October 1, 2016 - May 31, 2017. Amount: $5,526
(with Casian Pantea) Mathematical Association of America's Dolciani Mathematics Enrichment Grant Program. Title: West Virginia University Junior Math Club. Co-Principal Investigator. March 20, 2015 - May 31, 2017. Amount: $6,000
(with Adrian Tudorascu) NSF, DMS - 1400168, Applied Mathematics, Analysis Program, Award DMS-1400168. Title: Entropy and Singular Solutions for Conservation Laws; Pressureless Gas Dynamics and other applications. Co-Principal Investigator. May 1, 2014 - April 30, 2016. Amount: $37,000
WVU Internal award by the WVU ADVANCE Sponsorship Program, funded by NSF Advance-Institution Transformation, CLB-Advance-IT program under the Award HRD-1007978. Title: Symmetric Solutions to Hyperbolic Conservation Laws. Principal Investigator. October 1, 2014 - December 31, 2015. Amount: $15,000
Recent Talks:
88th Midwest PDE Seminar, The Ohio State University, Columbus, Department of Mathematics, April 27, 2024
41st Southeastern-Atlantic Regional Conference on Differential Equations, Florida A&M University in collaboration with Florida State University, Tallahassee, November 18-19, 2023
AMS Fall Eastern Sectional Meeting. Special Session: “Nonlinear Partial Differential Equations in Fluids and Waves”, Buffalo, NY, September 9, 2023
Joint Mathematics Meetings. Special Session: “Partial Differential Equations and Complex Variables”, Boston, MA, January 7, 2023
Organized the WVU Integration Bee, a mathematical competition open to all WVU and local high school students, Spring of 2014-2015 (with Casian Pantea), Spring of 2016-2018 (with Casian Pantea and Adrian Tudorascu), Spring of 2019, 2023-2025 (with Casian Pantea, Galyna Voitiuk and Iwona Wojciechowska), Spring of 2022 (with Ela Celikbas and Adrian Tudorascu)
Organized the WVU Junior Math Competition, a mathematical competition for high-school students, Spring 2017 (with Casian Pantea), Spring 2023 (with Casian Pantea, Galyna Voitiuk, and Qingtian Zhang), Fall 2024 (with Casian Pantea, and Galyna Voitiuk), Spring 2025 (with Casian Pantea, Galyna Voitiuk, and Iwona Wojciechowska)