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Hire Dr. Zacharias R.
Greece
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Astrophysicist PhD | Scientific Researcher Educator Writer Editor Communicator | Translator English/Greek
Profile Summary
Subject Matter Expertise
Services
Work Experience
Marie Curie Research Fellow
University of Milano-Bicocca
2024 - 2026 
Lecturer (Asst. Professor)
British University in Egypt
2019 - 2023
Adjunct Lecturer
University of Crete
February 2022 - August 2022
Adjunct Lecturer
University of Ioannina
2018 - 2019
Adjunct Lecturer
University of the Aegean
2017 - 2018
ERC Postdoctoral Research Fellow
Eötvös Loránd University
2015 - 2017
Postdoctoral Research Fellow
National Centre for Scientific Research-Demokritos
2014 - 2015
PhD scholarship
National Centre for Scientific Research-Demokritos
2009 - 2013
Education
PhD in Physics (Department of Physics and Applied Mathematics)
National Technical University of Athens
2009 - 2013
MSc in Nuclear and Particle Physics (Department of Physics)
National and Kapodistrian University of Athens
2004 - 2006
BSc in Physics (Department of Physics)
National and Kapodistrian University of Athens
1996 - 2000
Certifications
Publications
JOURNAL ARTICLE
Zacharias Roupas (2025). Black hole mass function shift in proto-stellar clusters driven by gas accretion . Astronomy & Astrophysics.
Zacharias Roupas (2025). Radical reform is needed to combat power abuses in academia . Nature Human Behaviour.
Roupas, Z.(2025). Radical reform is needed to combat power abuses in academia . Nature Human Behaviour.
Zacharias Roupas (2024). Self-gravitating isothermal sphere in an expanding background . Physical Review D.
Roupas, Z.(2024). Self-gravitating isothermal sphere in an expanding background . Physical Review D. 110. (12).
Zacharias Roupas (2023). Thermodynamic instability of dark energy equation of state . Physics of the Dark Universe.
Roupas, Z.(2023). Thermodynamic instability of dark energy equation of state . Physics of the Dark Universe. 40.
Roupas, Z.(2023). Thermodynamic instability of dark energy equation of state . Physics of the Dark Universe. 40.
Zacharias Roupas(2022). Detectable universes inside regular black holes . The European Physical Journal C. 82. (3). Springer Science and Business Media {LLC}
Roupas, Z.(2022). Detectable universes inside regular black holes . European Physical Journal C. 82. (3).
Thermodynamic origin of quantum time-energy uncertainty relation @article {
author = {Roupas, Zacharias and Autor correspondente: Roupas, Zacharias.},
title = {Thermodynamic origin of quantum time-energy uncertainty relation},
journal = {Journal of Statistical Mechanics: Theory and Experiment},
volume = {2021},
number = {9},
pages = {093207--093207},
year = {2021},
month = {sep},
url = {http://dx.doi.org/10.1088/1742-5468/ac21d5},
doi = {10.1088/1742-5468/ac21d5}
} . Journal of Statistical Mechanics: Theory and Experiment.
Zacharias Roupas(2021). Thermodynamic origin of quantum time–energy uncertainty relation . Journal of Statistical Mechanics: Theory and Experiment. 2021. (9). p. 093207. {IOP} Publishing
Zacharias Roupas, Grigoris Panotopoulos, Ilídio Lopes(2021). QCD color superconductivity in compact stars: Color-flavor locked quark star candidate for the gravitational-wave signal GW190814 . Physical Review D. 103. (8). American Physical Society ({APS})
Zacharias Roupas(2021). Gravitational Brownian motion as inhomogeneous diffusion: Black hole populations in globular clusters . Astronomy & Astrophysics. {EDP} Sciences
Zacharias Roupas(2021). Relativistic gravitational collapse by thermal mass . Communications in Theoretical Physics. 73. (1). p. 015401. {IOP} Publishing
Zacharias Roupas(2021). Secondary component of gravitational-wave signal GW190814 as an anisotropic neutron star . Astrophysics and Space Science. 366. (1). Springer Science and Business Media {LLC}
Roupas, Z., Panotopoulos, G., Lopes, I.(2021). QCD color superconductivity in compact stars: Color-flavor locked quark star candidate for the gravitational-wave signal GW190814 . Physical Review D. 103. (8).
Roupas, Z.(2021). Thermodynamic origin of quantum time-energy uncertainty relation . Journal of Statistical Mechanics: Theory and Experiment. 2021. (9).
Roupas, Z.(2021). Gravitational Brownian motion as inhomogeneous diffusion: Black hole populations in globular clusters . Astronomy and Astrophysics. 646.
Roupas, Z.(2021). Secondary component of gravitational-wave signal GW190814 as an anisotropic neutron star . Astrophysics and Space Science. 366. (1).
Roupas, Z.(2021). Relativistic gravitational collapse by thermal mass . Communications in Theoretical Physics. 73. (1).
Roupas, Z.(2021). Relativistic gravitational collapse by thermal mass . Communications in Theoretical Physics. 73. (1).
Zacharias Roupas, Amr A El-Zant, Joseph Silk(2020). Ejection of supermassive black holes and implications for merger rates in fuzzy dark matter haloes . Monthly Notices of the Royal Astronomical Society. Oxford University Press ({OUP})
(2020). Anisotropic neutron stars modelling: constraints in Krori–Barua spacetime . European Physical Journal C, 80, 905 (2020).
Ejection of supermassive black holes and implications for merger rates in fuzzy dark matter haloes @article {
author = {Amr A El-Zant and Zacharias Roupas and Joseph Silk},
title = {Ejection of supermassive black holes and implications for merger rates in fuzzy dark matter haloes},
journal = {Monthly Notices of the Royal Astronomical Society},
year = {2020},
month = {sep},
url = {https://doi.org/10.1093/mnras/staa2972},
doi = {10.1093/mnras/staa2972}
} . Monthly Notices of the Royal Astronomical Society.
Roupas, Zacharias, Nashed, Gamal G. L. (2020). Anisotropic neutron stars modelling: constraints in Krori-Barua spacetime . European Physical Journal C.
Zacharias Roupas(2020). Gravitational potential from maximum entropy principle . Classical and Quantum Gravity. {IOP} Publishing
Zacharias Roupas(2020). Gravitational potential from maximum entropy principle . Classical and Quantum Gravity. {IOP} Publishing
Zacharias Roupas(2020). Statistical mechanics of gravitational systems with regular orbits: rigid body model of vector resonant relaxation . Journal of Physics A: Mathematical and Theoretical. 53. (4). p. 045002. {IOP} Publishing
Roupas, Z.(2020). Statistical mechanics of gravitational systems with regular orbits: Rigid body model of vector resonant relaxation . Journal of Physics A: Mathematical and Theoretical. 53. (4).
Roupas, Z.(2020). Gravitational potential from maximum entropy principle . Classical and Quantum Gravity. 37. (9).
Roupas, Z., Nashed, G.G.L.(2020). Anisotropic neutron stars modelling: constraints in Krori–Barua spacetime . European Physical Journal C. 80. (10).
El-Zant, A.A., Roupas, Z., Silk, J.(2020). Ejection of supermassive black holes and implications for merger rates in fuzzy dark matter haloes . Monthly Notices of the Royal Astronomical Society. 499. (2). p. 2575-2586.
(2019). Generation of massive stellar black holes by rapid gas accretion in primordial dense clusters . Astronomy & Astrophysics.
Roupas, Zacharias, Kazanas, Demosthenes (2019). Generation of massive stellar black holes by rapid gas accretion in primordial dense clusters . Astronomy and Astrophysics.
(2019). Gravitational Instability Caused by the Weight of Heat . Symmetry.
(2019). Gravitational Instability Caused by the Weight of Heat . Symmetry.
Zacharias Roupas (2019). Gravitational Instability Caused by the Weight of Heat . Symmetry.
Roupas, Zacharias (2019). Gravitational Instability Caused by the Weight of Heat . Symmetry.
Zacharias Roupas, Pierre-Henri Chavanis (2019). Relativistic gravitational phase transitions and instabilities of the Fermi gas . Classical and Quantum Gravity.
Zacharias Roupas(2019). The Gravothermal Instability at All Scales: From Turnaround Radius to Supernovae . Universe. 5. (1). p. 12. {MDPI} {AG}
Zacharias Roupas (2019). The Gravothermal Instability at All Scales: From Turnaround Radius to Supernovae . Universe.
(2019). Binary black hole growth by gas accretion in stellar clusters . Astronomy & Astrophysics.
(2019). Binary black hole growth by gas accretion in stellar clusters . Astronomy & Astrophysics.
Roupas, Z.(2019). Gravitational instability caused by theweight of heat . Symmetry. 11. (12).
Roupas, Z., Chavanis, P.-H.(2019). Relativistic gravitational phase transitions and instabilities of the Fermi gas . Classical and Quantum Gravity. 36. (6).
Roupas, Z., Kazanas, D.(2019). Binary black hole growth by gas accretion in stellar clusters . Astronomy and Astrophysics. 621.
Roupas, Z.(2019). The gravothermal instability at all scales: From turnaround radius to supernovae . Universe. 5. (1).
Roupas, Z., Kazanas, D.(2019). Generation of massive stellar black holes by rapid gas accretion in primordial dense clusters . Astronomy and Astrophysics. 632.
(2018). Gravitational instability caused by the weight of heat . Symmetry.
{Roupas}, Z.(2018). Relativistic Gravothermal Instability: the Weight of Heat . ArXiv e-prints.
{Roupas}, Z.(2018). The Gravothermal Instability at all scales: from Turnaround Radius to Supernovae . ArXiv e-prints.
{Roupas}, Z. and {Kazanas}, D.(2018). Binary Black Holes Growth and Hardening by Gas Accretion in Stellar Clusters . ArXiv e-prints.
{Roupas}, Z. and {Chavanis}, P.-H.(2018). Relativistic Gravitational Phase Transitions and Instabilities of the Fermi Gas . ArXiv e-prints.
Zacharias Roupas, Bence Kocsis, Scott Tremaine (2017). Isotropic–Nematic Phase Transitions in Gravitational Systems . The Astrophysical Journal.
Zacharias Roupas, Bence Kocsis, Scott Tremaine (2017). Isotropic-Nematic Phase Transitions In Gravitational Systems . Zenodo.
Zacharias Roupas, Bence Kocsis, Scott Tremaine (2017). Isotropic-Nematic Phase Transitions In Gravitational Systems . Zenodo.
Zacharias Roupas, Bence Kocsis, Scott Tremaine (2017). Isotropic-Nematic Phase Transitions In Gravitational Systems . Zenodo.
Roupas, Zacharias, Kocsis, Bence, Tremaine, Scott (2017). Isotropic-Nematic Phase Transitions in Gravitational Systems . The Astrophysical Journal.
Roupas, Z., Kocsis, B., Tremaine, S.(2017). Isotropic-Nematic Phase Transitions in Gravitational Systems . Astrophysical Journal. 842. (2).
Zacharias Roupas(2015). Relativistic gravothermal instabilities . Classical and Quantum Gravity. 32. (13). p. 135023. {IOP} Publishing
Zacharias Roupas(2015). Corrigendum: Thermodynamical instabilities of perfect fluid spheres in General Relativity (2013Class. Quantum Grav.30115018) . Classical and Quantum Gravity. 32. (11). p. 119501. {IOP} Publishing
Zacharias Roupas(2015). Thermal mass limit of neutron cores . Physical Review D. 91. (2). American Physical Society ({APS})
Roupas, Z.(2015). Relativistic gravothermal instabilities . Classical and Quantum Gravity. 32. (13).
Roupas, Z.(2015). Thermal mass limit of neutron cores . Physical Review D - Particles, Fields, Gravitation and Cosmology. 91. (2).
Roupas, Z.(2015). Erratum: Thermodynamical instabilities of perfect fluid spheres in General Relativity (Class. Quantum Grav. (2013) 30 (115018)) . Classical and Quantum Gravity. 32. (11).
Zacharias Roupas, Minos Axenides, George Georgiou, Emmanuel N. Saridakis(2014). Galaxy clusters and structure formation in quintessence versus phantom dark energy universe . Physical Review D. 89. (8). American Physical Society ({APS})
Roupas, Z., Axenides, M., Georgiou, G., Saridakis, E.N.(2014). Galaxy clusters and structure formation in quintessence versus phantom dark energy universe . Physical Review D - Particles, Fields, Gravitation and Cosmology. 89. (8).
Zacharias Roupas, Minos Axenides, George Georgiou(2013). Gravitational instabilities of isothermal spheres in the presence of a cosmological constant . Nuclear Physics B. 871. (1). p. 21--51. Elsevier {BV}
Zacharias Roupas(2013). Thermodynamical instabilities of perfect fluid spheres in General Relativity . Classical and Quantum Gravity. 30. (11). p. 115018. {IOP} Publishing
Zacharias Roupas, Minos Axenides, George Georgiou(2013). Gravothermal instability with a cosmological constant in the canonical ensemble . Journal of Physics: Conference Series. 410. p. 012130. {IOP} Publishing
Axenides, M., Georgiou, G., Roupas, Z.(2013). Gravitational instabilities of isothermal spheres in the presence of a cosmological constant . Nuclear Physics B. 871. (1). p. 21-51.
Roupas, Z.(2013). Thermodynamical instabilities of perfect fluid spheres in General Relativity . Classical and Quantum Gravity. 30. (11).
Zacharias Roupas, Minos Axenides, George Georgiou(2012). Gravothermal catastrophe with a cosmological constant . Physical Review D. 86. (10). American Physical Society ({APS})
Zacharias Roupas(2012). Phase space geometry and chaotic attractors in dissipative Nambu mechanics . Journal of Physics A: Mathematical and Theoretical. 45. (19). p. 195101. {IOP} Publishing
Phase space geometry and chaotic attractors in dissipative Nambu mechanics @article {
author = {Zacharias Roupas},
title = {Phase space geometry and chaotic attractors in dissipative Nambu mechanics},
journal = {Journal of Physics A: Mathematical and Theoretical},
volume = {45},
number = {19},
pages = {195101--195101},
year = {2012},
month = {apr},
url = {https://doi.org/10.1088%2F1751-8113%2F45%2F19%2F195101},
doi = {10.1088/1751-8113/45/19/195101}
} . Journal of Physics A: Mathematical and Theoretical.
Roupas, Z.(2012). Phase space geometry and chaotic attractors in dissipative Nambu mechanics . Journal of Physics A: Mathematical and Theoretical. 45. (19).
Axenides, M., Georgiou, G., Roupas, Z.(2012). Gravothermal catastrophe with a cosmological constant . Physical Review D - Particles, Fields, Gravitation and Cosmology. 86. (10).
Lari, T., Pape, L., Porod, W., Aguilar-Saavedra, J.A., Allanach, B.C., Burdman, G., Castro, N., Klasen, M., Krasnikov, N., Krauss, F., et al.(2008). Collider aspects of flavor physics at high Q . European Physical Journal C. 57. (1-2). p. 183-307.
Collider aspects of flavor physics at high Q @article {
author = {Roupas, Zacharias},
title = {Collider aspects of flavor physics at high Q},
journal = {The European Physical Journal C},
volume = {57},
pages = {183--183},
year = {2008},
doi = {10.1140/epjc/s10052-008-0713-4}
} . The European Physical Journal C.
PREPRINT
Zacharias Roupas (2025). Radical reform is needed to combat power abuses in academia .
Zacharias Roupas (2025). Radical reform is needed to combat power abuses in academia .
(2020). Ejection of supermassive black holes and implications for merger rates in fuzzy dark matter haloes .
OTHER
Roupas, Z.(2024). Self-gravitating isothermal sphere in an expanding background . arXiv.
Roupas, Z.(2024). Self-gravitating isothermal sphere in an expanding background . arXiv.
Roupas, Z.(2023). Thermodynamic instability of dark energy equation of state . arXiv.
Roupas, Z.(2022). Detectable universes inside regular black holes . arXiv.
Roupas, Z.(2022). The Cosmological Black Hole . arXiv.
Roupas, Z.(2021). Thermodynamic origin of quantum time-energy uncertainty relation . arXiv.
Roupas, Z.(2020). Gravitational potential from maximum entropy principle . arXiv.
Roupas, Z., Nashed, G.G.L.(2020). Anisotropic Neutron Stars Modelling: Constraints in Krori-Barua Spacetime . arXiv.
El-Zant, A.A., Roupas, Z., Silk, J.(2020). Ejection of supermassive black holes and implications for merger rates in fuzzy dark matter haloes . arXiv.
Roupas, Z.(2020). Relativistic gravitational collapse by thermal mass . arXiv.
Roupas, Z.(2020). Gravitational brownian motion as inhomogeneous diffusion: Black hole populations in globular clusters . arXiv.
Roupas, Z.(2020). Secondary component of gravitational-wave signal GW190814 as an anisotropic neutron star . arXiv.
Roupas, Z., Panotopoulos, G., Lopes, I.(2020). QCD color superconductivity in compact stars: Color-flavor locked quark star candidate for the gravitational-wave signal GW190814 . arXiv.
Roupas, Z., Kazanas, D.(2019). Generation of massive stellar black holes by rapid gas accretion in primordial dense clusters . arXiv.
Roupas, Z.(2019). Statistical Mechanics of Gravitational Systems with Regular Orbits: Rigid Body Model of Vector Resonant Relaxation . arXiv.
Roupas, Z., Chavanis, P.-H.(2018). Relativistic gravitational phase transitions and instabilities of the fermi gas . arXiv.
Roupas, Z., Kazanas, D.(2018). Binary black hole growth by gas accretion in stellar clusters . arXiv.
Roupas, Z.(2018). The gravothermal instability at all scales: from turnaround radius to supernovae <sup>∗</sup> . arXiv.
Roupas, Z.(2018). The gravothermal instability at all scales: from turnaround radius to supernovae <sup>∗</sup> . arXiv.
Roupas, Z.(2018). Relativistic Gravothermal Instability: the Weight of Heat . arXiv.
Roupas, Z., Kocsis, B., Tremaine, S.(2017). Isotropic-nematic phase transitions in gravitational systems . arXiv.
CONFERENCE PAPER
Zacharias Roupas(2023). The cosmological black hole . 11TH INTERNATIONAL CONFERENCE ON MATHEMATICAL MODELING IN PHYSICAL SCIENCES. {AIP} Publishing
Roupas, Z.(2023). The cosmological black hole . AIP Conference Proceedings. 2872. (1).
(2013). Gravitational-thermodynamic instabilities of isothermal spheres in dS and AdS. Facultat de Fisica, Universitat de Barcelona
Gravitational-thermodynamic instabilities of isothermal spheres in dS and AdS @inproceedings {
author = {Roupas, Zacharias},
title = {Gravitational-thermodynamic instabilities of isothermal spheres in dS and AdS},
year = {2013},
month = {may},
booktitle = {Barcelona Postgrad Encounters on Fundamental Physics},
pages = {31--42},
publisher = {Facultat de Fisica, Universitat de Barcelona}
}.
Axenides, M., Georgiou, G., Roupas, Z.(2013). Gravothermal instability with a cosmological constant in the canonical ensemble . Journal of Physics: Conference Series. 410. (1).
WORKING PAPER
Roupas, Zacharias (2022). Detectable universes inside regular black holes. arXiv e-prints.
Roupas, Zacharias (2020). Gravitational potential from maximum entropy principle. arXiv e-prints.
Roupas, Zacharias (2019). Statistical Mechanics of Gravitational Systems with Regular Orbits: Rigid Body Model of Vector Resonant Relaxation. arXiv e-prints.
Roupas, Zacharias (2013). Gravitational-thermodynamic instabilities of isothermal spheres in dS and AdS. arXiv e-prints.
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