Welcome to the website supporting the virtual seminar series on Pseudo-Hermitian Hamiltonians in Quantum Physics.

This virtual seminar series is part of the regular real life seminar series on Pseudo-Hermitian Hamiltonians in Quantum Physics that was initiated by Miloslav Znojil in 2003. It is intended to bridge the gap, caused by the COVID-19 pandemic, between the real life XIXth meeting and the upcoming XXth meeting in Santa Fe in 2021. For past events see the PHHQP website. The subject matter of this series is the study of physical aspects of non-Hermitian systems from a theoretical and experimental point of view. Of special interest are systems that possess a PT-symmetry (a simultaneous reflection in space and time).

Proceedings: Journal of Physics: Conference Series Volume 2038


Upcoming: Sandra Klevansky, (Universität Heidelberg, Germany) 26/01/2023,15:00 London time (=15:00 GMT)

Underdetermined Dyson-Schwinger equations

Abstract: This talk examines the effectiveness of the Dyson-Schwinger (DS) equations as a calculational tool in quantum field theory. The DS equations are an infinite sequence of coupled equations that are satisfied exactly by the connected Green’s functions Gn of the field theory. These equations link lower to higher Green’s functions and, if they are truncated, the resulting finite system of equations is underdetermined. The simplest way to solve the underdetermined system is to set all higher Green’s function(s) to zero and then to solve the resulting determined system for the first few Green’s functions. The G1 or G2 so obtained can be compared with exact results in solvable models to see if the accuracy improves for high-order truncations. Five D=0 models are studied: Hermitian φ4 and φ6 and non-Hermitian iφ3, -φ4, and iφ5 theories. The truncated DS equations give a sequence of approximants that converge slowly to a limiting value but this limiting value always differs from the exact value by a few percent. More sophisticated truncation schemes based on mean-field-like approximations do not fix this formidable calculational problem.

This is joined work with Carl M. Bender and Christos Karapoulitidis

Check your local time here https://www.timeanddate.com/worldclock/

14:00 GMT = 15:00 in London = 10:00 New York = 23:00 Tokyo

Upcoming seminars

Sandra Klevansky, 26/01/23, 15:00 London time (=15:00 GMT)

Underdetermined Dyson-Schwinger equations

Wen-Yuan Ai, 09/02/23, 15:00 London time (=15:00 GMT)

A conjectural relation for the PT-symmetric -gφ 4-theory

Takanobu Taira, 23/02/23, 15:00 London time (=15:00 GMT)


Junggi Yoon, 09/03/23, 15:00 London time (=15:00 GMT)

TTbar deformation and negative norm states

The Seminars 2021: Term II – XIX(opens in a new tab)

Complete list of speakers

  1. Ali Mostafazadeh, (Koç University, Turkey) 07/05/2020
  2. Nick Mavromatos, (King’s College, Uni. of London, UK) 14/05/2020
  3. Phillip Mannheim, (University of Connecticut, US) 21/05/2020
  4. Fabio Bagarello, (University of Palermo, Italy) 04/06/2020
  5. Dorje Brody, (University of Surrey, UK) 18/06/2020
  6. Savannah Garmon, (Osaka Prefecture University, Japan) 02/07/2020
  7. Yogesh Joglekar, (Indiana Uni. Purdue University, US) 16/07/2020
  8. Andrei Smilga, (University of Nantes, France) 23/07/2020
  9. Eva-Maria Graefe, (Imperial College London, UK) 30/07/2020
  10. Avadh Saxena, (Los Alamos National Laboratory, US) 13/08/2020
  11. Li Ge, (City University of New York, US) 20/08/2020
  12. Carl Bender, (Washington University in St. Louis, US) 27/08/2020
  13. Vladimir Konotop, (Universidade de Lisboa, Portugal) 10/09/2020
  14. Joshua Feinberg, (University of Haifa and Technion, Israel) 24/09/2020
  15. Bhabani Prasad Mandal, (BHU, Varanasi, India) 08/10/2020
  16. Stéphane Boris Tabeu, (University of Yaounde, Cameroon) 15/10/2020
  17. Naomichi Hatano, (University of Tokyo, Japan) 22/10/2020
  18. Stefan Rotter, (Vienna University of Technology, Austria) 05/11/2020
  19. Maxim Chernodub, (Inst Denis Poisson, CNRS, France) 12/11/2020
  20. Pijush Ghosh, (Siksha-Bhavana, Visva-Bharati, India) 19/11/2020
  21. Mikhail Plyushchay, (Universidad de Santiago, Chile) 03/12/2020
  22. Qing-hai Wang, (National Univ. of Singapore, Singapore) 17/12/2020
  23. Gonzalo Muga, (University of the Basque Country, Spain) 14/01/2021
  24. Stella Schindler, (Massachusetts Institute of Technology, US) 21/01/2021
  25. Miloslav Znojil, (Nucl. Phys. Inst. of the AS, Czech Republic) 28/01/2021
  26. Roman Riser, (University of Haifa, Israel) 11/02/2021
  27. Duncan O’Dell, (McMaster University, Canada) 25/02/2021
  28. Mustapha Maamache, (Ferhat Abbas University, Algeria) 11/03/2021
  29. Andreas Ruschhaupt, (University College Cork, Ireland) 01/04/2021
  30. Hamidreza Ramezani, (Univ. of Texas Rio Grande Valley, US) 08/04/2021
  31. Andreas Fring, (City, University of London, UK) 22/04/2021
  32. Andrew Harter, (University of Tokyo, Japan) 06/05/2021
  33. Özlem Yeşiltaş, (Gazi University, Turkey) 20/05/2021
  34. Iveta Semorádová, (Czech Techn. Univ. Prague, Czech Republic) 03/06/2021
  35. Hugh Jones, (Imperial College London, UK) 17/06/2021
  36. Marta Reboiro, (University of La Plata, Argentina) 01/07/2021
  37. Ken Mochizuki, (Tohoku University, Japan) 15/07/2021
  38. Daniel Dizdarevic, (Universität Stuttgart, Germany) 29/07/2021
  39. Philip Mannheim, (University of Connecticut, US) 09/09/2021
  40. Latevi Lawson, (African Inst. for Math. Sciences, Ghana) 23/09/2021
  41. Jacob Muldoon, (Indiana University Purdue University, US) 30/09/2021
  42. Ross Wakefield, (University of Bristol, UK) 30/09/2021
  43. Abdelhafid Bounames, (University of Jijel, Algeria) 30/09/2021
  44. Himadri Barman, (Zhejiang University, China) 30/09/2021
  45. Andrei Smilga, (University of Nantes, France) 07/10/2021
  46. Takanobu Taira (City, University of London, UK) 14/10/2021
  47. Rebecca Tenney (City, University of London, UK) 14/10/2021
  48. Akhil Kumar, (Indian Inst. of Science Educ. and Res., India) 14/10/2021
  49. Kaustubh Argarwal, (Indiana University Purdue University, US) 14/10/2021
  50. Federico Roccati, (Università degli Studi di Palermo, Italy) 21/10/2021
  51. Ali Mostafazadeh, (Koç University, Turkey) 04/11/2021
  52. Yogesh Joglekar, (Indiana Uni. Purdue University, US) 18/11/2021
  53. Fabio Bagarello, (Università degli Studi di Palermo, Italy) 02/12/2021
  54. Kohei Kawabata, (University of Tokyo, Japan) 09/12/2021
  55. Tsuneya Yoshida, (University of Tsukuba, Japan) 16/12/2021
  56. Kazuki Yokomizo, (RIKEN National Science Institute, Japan) 06/01/2022
  57. Hamed Ghaemidizicheh, (Univ. Texas Rio Grande Valley, US) 20/01/2022
  58. Géza Lévai, (Institute for Nuclear Research, Hungary) 03/02/2022
  59. Aurelia Chenu, (University of Luxembourg, Luxembourg) 17/02/2022
  60. Adolfo del Campo, (Univ. of Luxembourg, Luxembourg) 03/03/2022
  61. Carl Bender, (Washington University in St. Louis, US) 17/03/2022
  62. Micheline Soley, (Yale Quantum Institute, US) 31/03/2022
  63. Michael Lubasch, (Quantinuum Ltd, UK) 14/04/2022
  64. Karl Landsteiner, (Inst. de Física Teórica UAM/CSIC, Spain) 28/04/2022
  65. Ion Cosma Fulga, (Leibniz Institute Dresden, Germany) 12/05/2022
  66. Barry Sanders, (University of Calgary, Canada) 26/05/2022
  67. Sujit Sarkar, (Poornaprajna Inst. of Scientific Res., India) 09/06/2022
  68. Gernot Akemann, (Universität Bielefeld, Germany) 23/06/2022
  69. Chia-Yi Ju, (National Sun Yat-sen University, Taiwan) 07/07/2022
  70. Eric Pap, (University of Groningen, The Netherlands) 21/07/2022
  71. Jan Wiersig, (Otto-von-Guericke University Magdeburg, Germany) 04/08/2022
  72. Stefan Rotter, (Vienna University of Technology, Austria) 06/10/2022
  73. Marco Merkli, (Memorial Univ. of Newfoundland, Canada) 13/10/2022
  74. Andrei Smilga, (University of Nantes, France) 20/10/2022
  75. Emil Bergholtz, (Stockholm University, Sweden) 27/10/2022
  76. Cancelled: Jacob Muldoon, (Indiana University Purdue Univ., US) 10/11/2022
  77. Fabio Bagarello, (Università degli Studi di Palermo, Italy) 24/11/2022
  78. Ali Mostafazadeh, (Koç University, Turkey) 01/12/2022
  79. Marta Reboiro, (University of La Plata, Argentina) 15/12/2022
  80. Carl Bender/Sandra Klevansky, (Washington University in St. Louis, US)/(Universität Heidelberg, Germany) 26/01/2023
  81. Wen-Yuan Ai, (King’s College London, UK) 09/02/2023
  82. Takanobu Taira, (The University of Tokyo, Japan) 23/02/2023
  83. Junggi Yoon, (Asia Pacific Center for Theoretical Physics, South Korea) 09/03/2023
  84. Latévi Lawson, (African Institute for Mathematical Sciences, Ghana) 23/03/2023
  85. Özlem Yeşiltaş, (Gazi University, Turkey) 09/04/2023