Dr. Lavrentios Kazantzidis

123339432_843614923050280_8273293846527441365_n

Personal Information

(+30) 26510 - 08451
l.kazantzidis@uoi.gr
lawrence.kazantzidis
Lavrentios Kazantzidis

Research Interests

My main research interests include theoretical and astrophysical aspects of cosmology, modified gravity theories (extensions of General Relavity), as well as cosmological data analysis.

Short Curriculum Vitae

Education



2017 – 2022         
Ph.D. in Physics
                                Thesis Title: “Cosmological Implications of Scalar Tensor Theories”
                                Department of Physics, University of Ioannina
2015 – 2017         Postgraduate Studies (M.Sc.) in Physics
                                Graduated with an overall grade 8.44/10.00
                                Department of Physics, University of Ioannina
2011 – 2015         Bachelor of Science certificate (B.Sc.) in Physics
                                Graduated with an overall grade 7.47/10.00
                                Department of Physics, University of Ioannina

Scholarships/Grants


2021 – Present    Tilted Cosmology
                                Role: Partner
                                Funding Source: Hellenic Foundation of Research and Innovation (HFRI) – “1st Call for Hellenic Foundation for Research and
                                Innovation Research Projects to support Faculty members and Researchers and the procurement of high-cost research equipment”.

2018 – 2021         Cosmological Aspects of Modified Theories of Gravity
                                Fellow of the Greek State Scholarships Foundation (IKY) for Ph.D. Studies.

Computer Skills


Operating Systems     Windows & Linux
Programming               C & Wolfram Mathematica
Scientific Software     (MG)CAMB, (MG)COSMOMC, CLASS, MontePython, LaTeX

Languages


Greek        Native
English      First Certificate in English (FCE)
                   Examination for the Certificate of Competency in English (ECCE)
French       Diplôme d’études en langue française (DELF) B1

Collaborations 


2021 – 2022    Snowmass2022 
2017 – 2021    Cosmology and Astrophysics Network for Theoretical Advances and Training Actions (CANTATA)

Peer Review 


Physics of the Dark Universe

Societies


2018 – Present    Junior Member of the Hellenic Society on Relativity, Gravitation and Cosmology

Publication Record

For the full list of my publications please visit the inspirehep database.

Cosmology Intertwined: A Review of the Particle Physics, Astrophysics, and Cosmology Associated with the Cosmological Tensions and Anomalies
E. Di Valentino et al., Contribution to the 2022 Snowmass Summer Study
JHEAp 34 (2022) 49-211
DOI: 10.1016/j.jheap.2022.04.002


Observational constraints on the deceleration parameter in a tilted universe
K. Asvesta, L. Kazantzidis, L. Perivolaropoulos and C. G. Tsagas
arXiv: 2202.00962, Supplemental Material


Late-transition vs smooth H(z) deformation models for the resolution of the Hubble crisis
G. Alestas, D. Camarena, E. Di Valentino, L. Kazantzidis, V. Marra, S. Nesseris and L. Perivolaropoulos
Phys. Rev. D 105, 063538
DOI: 10.1103/PhysRevD.105.063538, Supplemental Material


A w – M phantom transition at zt<0.1 as a resolution of the Hubble tension
G. Alestas, L. Kazantzidis, L. Perivolaropoulos
Phys.Rev.D 103 (2021) 8, 083517
DOI: 10.1103/PhysRevD.103.083517, Supplemental Material


Hints for possible low redshift oscillation around the best fit ΛCDM model in the expansion history of the universe
L. Kazantzidis, H. Koo, S. Nesseris, L. Perivolaropoulos, A. Shafieloo
Mon.Not.Roy.Astron.Soc. 501 (2021) 3, 3421-3426
DOI: 10.1093/mnras/staa3866


H0 tension, phantom dark energy, and cosmological parameter degeneracies
G. Alestas, L. Kazantzidis, L. Perivolaropoulos
Phys.Rev.D 101 (2020) 12, 123516
DOI: 10.1103/PhysRevD.101.123516, Supplemental Material


Hints of a Local Matter Underdensity or Modified Gravity in the Low z Pantheon data
L. Kazantzidis, L. Perivolaropoulos
Phys.Rev.D 102 (2020) 2, 023520
DOI: 10.1103/PhysRevD.102.023520, Supplemental Material


Hints of modified gravity in cosmos and in the lab?
Leandros Perivolaropoulos, Lavrentios Kazantzidis
Int.J.Mod.Phys.D 28 (2019) 05, 1942001, Invited Review for Special Issue on Modified Gravity
DOI: 10.1142/S021827181942001X


Constraining power of cosmological observables: blind redshift spots and optimal ranges
L. Kazantzidis, L. Perivolaropoulos, F. Skara
Phys.Rev.D 99 (2019) 6, 063537
DOI: 10.1103/PhysRevD.99.063537, Supplemental Material


σ8 Tension. Is gravity getting weaker at low z? Observational evidence and theoretical implications
Lavrentios Kazantzidis, Leandros Perivolaropoulos
Invited contribution for the White Paper of COST CA-15117 project “CANTATA” (Cosmology and Astrophysics Network for Theoretical Advances and Training   Actions) “Observational Discriminators” section.
DOI: 10.1007/978-3-030-83715-0_33, arXiv: 1907.03176, Supplemental Material


Consistency of modified gravity with a decreasing  Geff (z) in a ΛCDM background
Radouane Gannouji, Lavrentios Kazantzidis, Leandros Perivolaropoulos, David Polarski
Phys.Rev.D 98 (2018) 10, 104044
DOI: 10.1103/PhysRevD.98.104044, Supplemental Material


Evolution of the 8 tension with the Planck15/ΛCDM determination and implications for modified gravity theories
Lavrentios Kazantzidis, Leandros Perivolaropoulos
Phys.Rev.D 97 (2018) 10, 103503
DOI: 10.1103/PhysRevD.97.103503, Supplemental Material

Experience

Teaching Assistance


Winter Semesters 2017 – 2022     Classical Electrodynamics I (5th Semester Core Course – 52)
                                                              Department of Physics, University of Ioannina, Greece
Spring Semesters 2020 – 2022     Cosmology (Advanced Undergraduate Elective Course – 105)
                                                              Department of Physics, University of Ioannina, Greece
Spring Semesters 2018 – 2019     Gravity and Cosmology (Advanced Graduate Elective Course – M122) 
                                                              Department of Physics, University of Ioannina, Greece

M.Sc. Diploma Thesis


Title: Dark Energy from Generalized Gravitational Theories with a Time-dependent Newton’s Constant (scalar tensor theories).
Abstract:
This work is focused on alternative forms of Dark Energy. The challenges that the ΛCDM model faces led to a variety of alternative models, such as extra dimensions, quintessence models, $f(R)$ extended gravity theories, scalar tensor quintessence models etc. The main goal of my master thesis is to investigate the cosmological dynamics for general scalar tensor quintessence field models. Firstly, we introduce the reader to the mathematical formalism of  Standard Cosmology and then, we study alternative theories that can play the role of Dark Energy such as quintessence models based on linear-negative potentials of the form $V (\phi) = −s \, \phi$. In the second part of this work we review the scalar tensor quintessence field models and their theoretical background. We investigate the equation of state parameter $w(z)$ for these particular models and we use the Union2.1 dataset of 580 SnIa as a validity test and to explore the observational consistency of the theoretical model and its predictions for the fate of our Universe. Finally we study qualitatively different potentials of the form $V = s \, |\phi|^{n}$ and use, once again the Union2.1 dataset as a consistency test of our model.  

You can see my full M.Sc. thesis here