World's Best Scientists 2026 revealed!
VIEW LIST
Romain Teyssier

D-Index & Metrics

Discipline name D-Index World Ranking Current World Ranking National Ranking Current National Ranking Publications Citations
Physics 100 1646 1566 36 36 344 37678

Romain Teyssier publications per year

The chart shows the history of publications by Romain Teyssier between 1978 and 2026, highlighting the no. of papers published in each year and offering an overview of the publication velocity of this scholar. Romain Teyssier published across 49 years, from 1978 to 2026, averaging 8.4 papers a year. Output peaked at 34 publications in 2010. 30 of the 414 publications appeared in the last two years.

No. of publications
10 20 30
Bar chart. Horizontal axis: year, 1978 to 2026. Vertical axis: number of publications, 0 to 34. Peak 34 publications in 2010. 1978: 1 publication 1979: 0 publications 1980: 0 publications 1981: 2 publications 1982: 0 publications 1983: 0 publications 1984: 0 publications 1985: 1 publication 1986: 0 publications 1987: 0 publications 1988: 0 publications 1989: 1 publication 1990: 0 publications 1991: 0 publications 1992: 0 publications 1993: 0 publications 1994: 3 publications 1995: 0 publications 1996: 1 publication 1997: 4 publications 1998: 4 publications 1999: 6 publications 2000: 3 publications 2001: 7 publications 2002: 4 publications 2003: 3 publications 2004: 5 publications 2005: 3 publications 2006: 12 publications 2007: 18 publications 2008: 20 publications 2009: 22 publications 2010: 34 publications 2011: 26 publications 2012: 19 publications 2013: 14 publications 2014: 14 publications 2015: 21 publications 2016: 10 publications 2017: 13 publications 2018: 15 publications 2019: 8 publications 2020: 18 publications 2021: 21 publications 2022: 18 publications 2023: 12 publications 2024: 21 publications 2025: 27 publications 2026: 3 publications
1978 2026

414 publications in total across all disciplines

View publications per year as a table
Romain Teyssier: publications per year, 1978 to 2026
Year Publications
1978 1
1979 0
1980 0
1981 2
1982 0
1983 0
1984 0
1985 1
1986 0
1987 0
1988 0
1989 1
1990 0
1991 0
1992 0
1993 0
1994 3
1995 0
1996 1
1997 4
1998 4
1999 6
2000 3
2001 7
2002 4
2003 3
2004 5
2005 3
2006 12
2007 18
2008 20
2009 22
2010 34
2011 26
2012 19
2013 14
2014 14
2015 21
2016 10
2017 13
2018 15
2019 8
2020 18
2021 21
2022 18
2023 12
2024 21
2025 27
2026 3
Total 414
Download as CSV

Romain Teyssier publication distribution in Physics in 2026

The chart shows the distribution of publications by all Research.com ranked scientists in the field of Physics in 2026. The highlighted bar marks where Romain Teyssier sits on this spectrum.

No. of scientists
50 100 150
Bar chart with 70 bars. Horizontal axis: publications, 103–122 to 1,469+. Vertical axis: number of scientists, 0 to 162. Most scientists, 162, have 323–342 publications. The last bar groups every scientist with 1,469 publications or more. The highlighted bar, 343–362 publications, is where this scientist sits. 103–122 publications: 7 scientists 123–142 publications: 10 scientists 143–162 publications: 31 scientists 163–182 publications: 35 scientists 183–202 publications: 53 scientists 203–222 publications: 81 scientists 223–242 publications: 85 scientists 243–262 publications: 112 scientists 263–282 publications: 114 scientists 283–302 publications: 126 scientists 303–322 publications: 136 scientists 323–342 publications: 162 scientists 343–362 publications: 155 scientists 363–382 publications: 156 scientists 383–402 publications: 134 scientists 403–422 publications: 145 scientists 423–442 publications: 147 scientists 443–462 publications: 131 scientists 463–482 publications: 131 scientists 483–502 publications: 116 scientists 503–522 publications: 106 scientists 523–542 publications: 103 scientists 543–562 publications: 87 scientists 563–582 publications: 84 scientists 583–602 publications: 94 scientists 603–622 publications: 70 scientists 623–642 publications: 76 scientists 643–662 publications: 60 scientists 663–682 publications: 54 scientists 683–702 publications: 60 scientists 703–722 publications: 48 scientists 723–742 publications: 64 scientists 743–762 publications: 48 scientists 763–782 publications: 37 scientists 783–802 publications: 43 scientists 803–822 publications: 34 scientists 823–842 publications: 36 scientists 843–862 publications: 32 scientists 863–882 publications: 32 scientists 883–902 publications: 31 scientists 903–922 publications: 25 scientists 923–942 publications: 15 scientists 943–962 publications: 24 scientists 963–982 publications: 13 scientists 983–1,002 publications: 21 scientists 1,003–1,022 publications: 21 scientists 1,023–1,042 publications: 16 scientists 1,043–1,062 publications: 9 scientists 1,063–1,082 publications: 19 scientists 1,083–1,102 publications: 11 scientists 1,103–1,122 publications: 17 scientists 1,123–1,142 publications: 11 scientists 1,143–1,162 publications: 7 scientists 1,163–1,182 publications: 4 scientists 1,183–1,202 publications: 10 scientists 1,203–1,222 publications: 8 scientists 1,223–1,242 publications: 16 scientists 1,243–1,262 publications: 4 scientists 1,263–1,282 publications: 10 scientists 1,283–1,302 publications: 5 scientists 1,303–1,322 publications: 7 scientists 1,323–1,342 publications: 4 scientists 1,343–1,362 publications: 8 scientists 1,363–1,382 publications: 6 scientists 1,383–1,402 publications: 7 scientists 1,403–1,422 publications: 3 scientists 1,423–1,442 publications: 4 scientists 1,443–1,462 publications: 4 scientists 1,463–1,468 publications: 3 scientists 1,469+ publications: 100 scientists
103–122 publications 1,469+

This scientist: 344 publications — 26th percentile

26% of scientists in this discipline score the same or lower.

The last bar groups every scientist with 1,469 publications or more.

View publications distribution as a table
Number of Physics scientists by publication count, Research.com 2026 ranking edition. Based on 3,678 ranked scientists.
Publications Scientists This scientist
103–122 7
123–142 10
143–162 31
163–182 35
183–202 53
203–222 81
223–242 85
243–262 112
263–282 114
283–302 126
303–322 136
323–342 162
343–362 155 344
363–382 156
383–402 134
403–422 145
423–442 147
443–462 131
463–482 131
483–502 116
503–522 106
523–542 103
543–562 87
563–582 84
583–602 94
603–622 70
623–642 76
643–662 60
663–682 54
683–702 60
703–722 48
723–742 64
743–762 48
763–782 37
783–802 43
803–822 34
823–842 36
843–862 32
863–882 32
883–902 31
903–922 25
923–942 15
943–962 24
963–982 13
983–1,002 21
1,003–1,022 21
1,023–1,042 16
1,043–1,062 9
1,063–1,082 19
1,083–1,102 11
1,103–1,122 17
1,123–1,142 11
1,143–1,162 7
1,163–1,182 4
1,183–1,202 10
1,203–1,222 8
1,223–1,242 16
1,243–1,262 4
1,263–1,282 10
1,283–1,302 5
1,303–1,322 7
1,323–1,342 4
1,343–1,362 8
1,363–1,382 6
1,383–1,402 7
1,403–1,422 3
1,423–1,442 4
1,443–1,462 4
1,463–1,468 3
1,469+ 100
Download as CSV

Romain Teyssier D-index placement in Physics in 2026

The chart shows the D-index (discipline H-index) distribution of Physics scientists ranked by Research.com in 2026. The highlighted bar marks where Romain Teyssier sits on this spectrum.

No. of scientists
50 100 150
Bar chart with 59 bars. Horizontal axis: D-Index, 70–71 to 185+. Vertical axis: number of scientists, 0 to 167. Most scientists, 167, have 80–81 D-Index. The last bar groups every scientist with 185 D-Index or more. The highlighted bar, 100–101 D-Index, is where this scientist sits. 70–71 D-Index: 76 scientists 72–73 D-Index: 110 scientists 74–75 D-Index: 143 scientists 76–77 D-Index: 153 scientists 78–79 D-Index: 144 scientists 80–81 D-Index: 167 scientists 82–83 D-Index: 167 scientists 84–85 D-Index: 166 scientists 86–87 D-Index: 132 scientists 88–89 D-Index: 155 scientists 90–91 D-Index: 134 scientists 92–93 D-Index: 137 scientists 94–95 D-Index: 102 scientists 96–97 D-Index: 112 scientists 98–99 D-Index: 110 scientists 100–101 D-Index: 116 scientists 102–103 D-Index: 97 scientists 104–105 D-Index: 103 scientists 106–107 D-Index: 87 scientists 108–109 D-Index: 90 scientists 110–111 D-Index: 67 scientists 112–113 D-Index: 78 scientists 114–115 D-Index: 75 scientists 116–117 D-Index: 67 scientists 118–119 D-Index: 69 scientists 120–121 D-Index: 60 scientists 122–123 D-Index: 59 scientists 124–125 D-Index: 53 scientists 126–127 D-Index: 42 scientists 128–129 D-Index: 41 scientists 130–131 D-Index: 33 scientists 132–133 D-Index: 32 scientists 134–135 D-Index: 45 scientists 136–137 D-Index: 19 scientists 138–139 D-Index: 24 scientists 140–141 D-Index: 28 scientists 142–143 D-Index: 31 scientists 144–145 D-Index: 22 scientists 146–147 D-Index: 20 scientists 148–149 D-Index: 12 scientists 150–151 D-Index: 16 scientists 152–153 D-Index: 24 scientists 154–155 D-Index: 23 scientists 156–157 D-Index: 15 scientists 158–159 D-Index: 15 scientists 160–161 D-Index: 11 scientists 162–163 D-Index: 17 scientists 164–165 D-Index: 12 scientists 166–167 D-Index: 11 scientists 168–169 D-Index: 9 scientists 170–171 D-Index: 9 scientists 172–173 D-Index: 11 scientists 174–175 D-Index: 4 scientists 176–177 D-Index: 8 scientists 178–179 D-Index: 5 scientists 180–181 D-Index: 3 scientists 182–183 D-Index: 4 scientists 184 D-Index: 4 scientists 185+ D-Index: 99 scientists
70–71 D-Index 185+

This scientist: 100 D-Index — 56th percentile

56% of scientists in this discipline score the same or lower.

The last bar groups every scientist with 185 D-Index or more.

View D-Index distribution as a table
Number of Physics scientists by D-index, Research.com 2026 ranking edition. Based on 3,678 ranked scientists.
D-Index Scientists This scientist
70–71 76
72–73 110
74–75 143
76–77 153
78–79 144
80–81 167
82–83 167
84–85 166
86–87 132
88–89 155
90–91 134
92–93 137
94–95 102
96–97 112
98–99 110
100–101 116 100
102–103 97
104–105 103
106–107 87
108–109 90
110–111 67
112–113 78
114–115 75
116–117 67
118–119 69
120–121 60
122–123 59
124–125 53
126–127 42
128–129 41
130–131 33
132–133 32
134–135 45
136–137 19
138–139 24
140–141 28
142–143 31
144–145 22
146–147 20
148–149 12
150–151 16
152–153 24
154–155 23
156–157 15
158–159 15
160–161 11
162–163 17
164–165 12
166–167 11
168–169 9
170–171 9
172–173 11
174–175 4
176–177 8
178–179 5
180–181 3
182–183 4
184 4
185+ 99
Download as CSV

Overview

Romain Teyssier is affiliated with the University of Zurich in Switzerland and has contributed extensively to research in the field of Physics and Astronomy. Their scientific output includes numerous publications focused on Astronomy and Astrophysics, Instrumentation, Computational Mechanics, Nuclear and High Energy Physics, and Statistical and Nonlinear Physics.

The scientist's research encompasses multiple topics such as:

  • Galaxies: Formation, Evolution, Phenomena
  • Astronomy and Astrophysical Research
  • Astrophysics and Star Formation Studies
  • Stellar, planetary, and galactic studies
  • Astrophysics and Cosmic Phenomena
  • Cosmology and Gravitation Theories
  • Gamma-ray bursts and supernovae

Frequent co-authors with whom Romain Teyssier has collaborated include:

  • Pierre Ocvirk
  • Paul R. Shapiro
  • Joseph S. W. Lewis
  • Gustavo Yepes
  • Kyungjin Ahn

Publications by Romain Teyssier are often found in key scientific venues, including:

  • arXiv (Cornell University)
  • Monthly Notices of the Royal Astronomical Society
  • The Astrophysical Journal
  • Astronomy and Astrophysics
  • Journal of Cosmology and Astroparticle Physics

Among recent papers authored or co-authored by Romain Teyssier are:

  • Euclid Spectroscopic Image Simulations and Reconstruction, 2024, arXiv (Cornell University)
  • Cosmic Dawn II (CoDa II): a new radiation-hydrodynamics simulation of the self-consistent coupling of galaxy formation and reionization, 2020, Monthly Notices of the Royal Astronomical Society
  • Euclid preparation: IX. EuclidEmulator2 - power spectrum emulation with massive neutrinos and self-consistent dark energy perturbations, 2021, Monthly Notices of the Royal Astronomical Society
  • Efficient early stellar feedback can suppress galactic outflows by reducing supernova clustering, 2021, Monthly Notices of the Royal Astronomical Society
  • Baryonic effects for weak lensing. Part I. Power spectrum and covariance matrix, 2020, Journal of Cosmology and Astroparticle Physics

Best Publications

  • Cold streams in early massive hot haloes as the main mode of galaxy formation.

    A. Dekel;Y. Birnboim;Y. Birnboim;G. Engel;J. Freundlich

  • Cosmological hydrodynamics with adaptive mesh refinement - A new high resolution code called RAMSES

    Romain Teyssier

  • Euclid Definition Study Report

    R. Laureijs;J. Amiaux;S. Arduini;J.-L. Auguères

  • Fundamental differences between SPH and grid methods

    Oscar Agertz;Ben Moore;Joachim Stadel;Doug Potter

  • Dancing in the dark: galactic properties trace spin swings along the cosmic web

    Y. Dubois;C. Pichon;C. Welker;C. Welker;D. Le Borgne

  • Morphological Quenching of Star Formation: Making Early-Type Galaxies Red

    Marie Martig;Frédéric Bournaud;Romain Teyssier;Avishai Dekel

  • Fundamental differences between SPH and grid methods

    Oscar Agertz;Ben Moore;Joachim Stadel;Doug Potter

  • A High Order Godunov Scheme with Constrained Transport and Adaptive Mesh Refinement for Astrophysical MHD

    S.Fromang;P.Hennebelle;R.Teyssier

  • The Aquila comparison project: the effects of feedback and numerical methods on simulations of galaxy formation

    C. Scannapieco;M. Wadepuhl;O.H. Parry;O.H. Parry;J.F. Navarro

  • Bimodal gas accretion in the Horizon–MareNostrum galaxy formation simulation

    P. Ocvirk;C. Pichon;C. Pichon;R. Teyssier

  • Cusp-core transformations in dwarf galaxies: observational predictions

    Romain Teyssier;Romain Teyssier;Andrew Pontzen;Yohan Dubois;Justin I. Read;Justin I. Read

  • A high order Godunov scheme with constrained transport and adaptive mesh refinement for astrophysical magnetohydrodynamics

    Sebastien Fromang;Sebastien Fromang;P. Hennebelle;R. Teyssier

  • The formation of disc galaxies in a LCDM universe

    Oscar Agertz;Romain Teyssier;Ben Moore

  • Self-regulated growth of supermassive black holes by a dual jet/heating AGN feedback mechanism: methods, tests and implications for cosmological simulations

    Yohan Dubois;Julien Devriendt;Adrianne Slyz;Romain Teyssier

  • ISM properties in hydrodynamic galaxy simulations: turbulence cascades, cloud formation, role of gravity and feedback

    Frédéric Bournaud;Bruce G. Elmegreen;Romain Teyssier;David L. Block

  • Self-regulated growth of supermassive black holes by a dual jet-heating active galactic nucleus feedback mechanism: methods, tests and implications for cosmological simulations

    Yohan Dubois;Julien Devriendt;Julien Devriendt;Adrianne Slyz;Romain Teyssier;Romain Teyssier

  • Black Hole growth and AGN obscuration by instability-driven inflows in high-redshift disk galaxies fed by cold streams

    Frederic Bournaud;Avishai Dekel;Romain Teyssier;Marcello Cacciato

  • The formation of disc galaxies in a ΛCDM universe

    Oscar Agertz;Romain Teyssier;Romain Teyssier;Ben Moore

  • On the onset of galactic winds in quiescent star forming galaxies

    Yohan Dubois;Romain Teyssier

  • Cosmological constraints from archeops

    Alain Benoit;P. Ade;A. Amblard;R. Ansari

Frequent Co-Authors

Frédéric Bournaud
Frédéric Bournaud University of Paris-Saclay
Ben Moore
Ben Moore University of Zurich
Simon Prunet
Simon Prunet Observatoire de la Côte d’Azur
Avishai Dekel
Avishai Dekel Hebrew University of Jerusalem
Gilles Chabrier
Gilles Chabrier École Normale Supérieure de Lyon
Gustavo Yepes
Gustavo Yepes Autonomous University of Madrid
Joachim Stadel
Joachim Stadel University of Zurich
Patrick Hennebelle
Patrick Hennebelle University of Paris-Saclay
François R. Bouchet
François R. Bouchet Institut d'Astrophysique de Paris
Lucio Mayer
Lucio Mayer University of Zurich

External Links

Personal website of Romain Teyssier

If you think any of the details on this page are incorrect, let us know.

Report an issue

We appreciate your kind effort to assist us to improve this page, it would be helpful providing us with as much detail as possible in the text box below:

Best Scientists Citing Romain Teyssier

Volker Springel

Volker Springel

Max Planck Institute for Astrophysics

Publications: 271

Avishai Dekel

Avishai Dekel

Hebrew University of Jerusalem

Publications: 177

Joop Schaye

Joop Schaye

Leiden University

Publications: 149

Romeel Davé

Romeel Davé

University of Edinburgh

Publications: 149

Joseph Silk

Joseph Silk

Johns Hopkins University

Publications: 141

Frédéric Bournaud

Frédéric Bournaud

University of Paris-Saclay

Publications: 136

Patrick Hennebelle

Patrick Hennebelle

University of Paris-Saclay

Publications: 133

Philip F. Hopkins

Philip F. Hopkins

California Institute of Technology

Publications: 128

Ralf S. Klessen

Ralf S. Klessen

Heidelberg University

Publications: 123

Anton M. Koekemoer

Anton M. Koekemoer

Space Telescope Science Institute

Publications: 121

Mark Vogelsberger

Mark Vogelsberger

MIT

Publications: 121

Emanuele Daddi

Emanuele Daddi

University of Paris-Saclay

Publications: 116

Andreas Burkert

Andreas Burkert

Ludwig-Maximilians-Universität München

Publications: 115

Tom Theuns

Tom Theuns

Durham University

Publications: 115

Stefano Borgani

Stefano Borgani

University of Trieste

Publications: 113

Shy Genel

Shy Genel

Columbia University

Publications: 108

Trending Scientists

Andreas Fery

Andreas Fery

Leibniz-Institut für Polymerforschung Dresden e. V.

Peter Donnelly

Peter Donnelly

University of Oxford

David Pommerenke

David Pommerenke

Graz University of Technology

Tsung-Ping Su

Tsung-Ping Su

National Institute on Drug Abuse

Amalia Conte

Amalia Conte

University of Foggia

Dario Grattapaglia

Dario Grattapaglia

Brazilian Agricultural Research Corporation

Pierre Casellas

Pierre Casellas

Sanofi (France)

Hans Jörnvall

Hans Jörnvall

Karolinska Institute

Boaz Luz

Boaz Luz

Hebrew University of Jerusalem

Huub M. Toussaint

Huub M. Toussaint

Amsterdam University of Applied Sciences

Ali Akbar Shaikh

Ali Akbar Shaikh

University of Burdwan

Peter Y. A. Ryan

Peter Y. A. Ryan

University of Luxembourg

Thomas Diez

Thomas Diez

University of Tübingen

Han Dorussen

Han Dorussen

University of Essex

Valery E. Forbes

Valery E. Forbes

University of Minnesota

S. Peter Henzi

S. Peter Henzi

University of Lethbridge

Related Physics Rankings & Guides

2027 Best Online Space Studies Degree Programs

2027 Best Online Space Studies Degree Programs
2027 Online Photography Degree Programs Costs: Tuition & Fees

2027 Online Photography Degree Programs Costs: Tuition & Fees
2027 How To Become a Paleontologist? Salary & Career Paths

2027 How To Become a Paleontologist? Salary & Career Paths
2027 Online Photography Degree Programs for Veterans: GI Bill Benefits, Costs & Top Considerations

2027 Online Photography Degree Programs for Veterans: GI Bill Benefits, Costs & Top Considerations
2027 Best Online Physics Degree Programs

2027 Best Online Physics Degree Programs
2027 Most Affordable Online Physics Degree Programs

2027 Most Affordable Online Physics Degree Programs
2027 Most Affordable Online Space Studies Degree Programs

2027 Most Affordable Online Space Studies Degree Programs
2027 Fastest Online Urban Planning Degree Programs You Can Finish in Under 2 Years

2027 Fastest Online Urban Planning Degree Programs You Can Finish in Under 2 Years
2027 Admission Requirements for Physics Degree Programs

2027 Admission Requirements for Physics Degree Programs

Recently Published Articles

2027 Military-Friendly Online Human Resource Management Degree Programs: Benefits, Accreditation, and Career Outcomes

2027 Military-Friendly Online Human Resource Management Degree Programs: Benefits, Accreditation, and Career Outcomes
2027 What is a PACU Nurse: Salary & Career Paths?

2027 What is a PACU Nurse: Salary & Career Paths?
2027 How to Become a Middle School Math Teacher in Ohio: Requirements & Certification

2027 How to Become a Middle School Math Teacher in Ohio: Requirements & Certification
2027 Fastest Online Master’s Degree in Nonprofit Management

2027 Fastest Online Master’s Degree in Nonprofit Management
2027 Most Affordable Online Master’s Degrees in Human Resources

2027 Most Affordable Online Master’s Degrees in Human Resources
2027 Hardest and Easiest Courses in an Architecture Degree Program

2027 Hardest and Easiest Courses in an Architecture Degree Program
2027 Cheapest Way to Get a Teaching Credential in Mississippi: Requirements & Certification

2027 Cheapest Way to Get a Teaching Credential in Mississippi: Requirements & Certification
2027 Youth and Family Ministry Master's Degree Licensure Requirements by State

2027 Youth and Family Ministry Master's Degree Licensure Requirements by State
2027 Are Online Occupational Therapy Degrees Respected by Employers?

2027 Are Online Occupational Therapy Degrees Respected by Employers?
2027 Best Online Masters in Business Intelligence Programs

2027 Best Online Masters in Business Intelligence Programs
2027 Best Family Nurse Practitioner Degrees for Working Adults

2027 Best Family Nurse Practitioner Degrees for Working Adults
2027 Online Doctor of Education (EdD) Programs with No Residency Requirement

2027 Online Doctor of Education (EdD) Programs with No Residency Requirement
2027 Occupational Therapy Degree Programs for Career Changers

2027 Occupational Therapy Degree Programs for Career Changers
2027 Is a 2-Year Applied Science Degree Worth It: Accelerated Bachelor's ROI & Time Trade-Offs

2027 Is a 2-Year Applied Science Degree Worth It: Accelerated Bachelor's ROI & Time Trade-Offs
2027 How to Become a Mechanic in Louisiana: Requirements & Certification

2027 How to Become a Mechanic in Louisiana: Requirements & Certification
2027 Shortest Online Psychiatric Mental Health Nurse Practitioner Degree Master's Programs That Pay Well: Cost, Time to Completion, and Salary Outlook

2027 Shortest Online Psychiatric Mental Health Nurse Practitioner Degree Master's Programs That Pay Well: Cost, Time to Completion, and Salary Outlook
2027 Which Psychiatric Mental Health Nurse Practitioner Degree Careers Offer the Best Work-Life Balance?

2027 Which Psychiatric Mental Health Nurse Practitioner Degree Careers Offer the Best Work-Life Balance?
2027 Highest-Paying Jobs You Can Get With a Psychology Degree

2027 Highest-Paying Jobs You Can Get With a Psychology Degree
2027 Online Pharmacy Degree Programs Costs: Tuition & Fees

2027 Online Pharmacy Degree Programs Costs: Tuition & Fees
2027 Online Respiratory Care Therapy Bachelor's Degree Programs With No Prerequisites

2027 Online Respiratory Care Therapy Bachelor's Degree Programs With No Prerequisites
2027 How to Become a Caregiver: Certification Requirements in Georgia

2027 How to Become a Caregiver: Certification Requirements in Georgia