#  Practicing carpe diem in the journey of studying physics
—A brief review of the scientific contribution of Ru-Keng Su

Shaoyu Yin1 Wei-Liang Qian2,3 Ping Wang4 Bin Wang3,5 Rong-Gen Cai6,7,8 1
Institute for Theoretical Physics & Cosmology, Zhejiang University of
Technology, Hangzhou 310032, China  2 Escola de Engenharia de Lorena,
Universidade de São Paulo, 12602-810, Lorena, SP, Brazil  3 Center for
Gravitation and Cosmology, College of Physical Science and Technology,
Yangzhou University, Yangzhou 225009, China  4 Institute of High Energy
Physics, CAS, P. O. Box 918(4), Beijing 100049, China  5 School of Aeronautics
and Astronautics, Shanghai Jiao Tong University, Shanghai 200240, China  6 CAS
Key Laboratory of Theoretical Physics, Institute of Theoretical Physics,
Chinese Academy of Sciences, Beijing 100190, China  7 School of Physical
Sciences, University of Chinese Academy of Sciences, Beijing 100049, China  8
School of Fundamental Physics and Mathematical Sciences, Hangzhou Institute
for Advanced Study, University of Chinese Academy of Sciences, Hangzhou
310024, China

(Oct. 12th, 2022)

###### Abstract

We briefly review the scientific contributions of the late Prof. Ru-Keng Su in
his academic life. In the area of intermediate and high-energy nuclear
physics, Su explored various topics in high-energy nuclear physics and
particle physics, inclusively about the finite temperature field theory,
effective models for nuclear and quark matter, soliton, and quasiparticle
models, among others. In gravity and cosmology, Su’s research primarily
embraces black hole thermodynamics, quasinormal modes, cosmological microwave
background radiation, modified theories of gravity, and AdS/CFT correspondence
and its applications. Besides, many aspects of Su’s distinguished impact on
the Chinese academic physics community are discussed. We also summarize the
biographical and academic career of Su. This article is an elaborated version
of the memorial article that will be published in symmetry.

##  I Introduction

Ru-Keng Su (May 27, 1938 - June 3, 2022) was a highly respected Chinese
theoretical physicist whose research interests span from the depth of the
subatomic realm to the far reaches of the universe. During his academic
career, Su made notable contributions to intermediate and high-energy nuclear
physics, general relativity, and cosmology. As one of the leading physicists
in China, he has assisted in developing Chinese physical society to date. This
article elaborates on a few scientific results in memory of Su’s contributions
to the community.

The remainder of the article is organized as follows. The following Sec. II.1
and II.2 are devoted to discussing Su’s contributions, respectively, to the
areas of nuclear and particle physics and general relativity. We give a brief
account of relevant studies and, inclusively, those carried out in
collaboration with his students and collaborators. The appendices consist of a
brief biography and a summary of academic achievements of Su. As his
disciples, we understand that it would be beneficial and educative for the
followers to revisit his academic achievements as well as the personal life of
our beloved supervisor. With the help of his family and friends, we tried to
collect as much information as possible. Although we are aware that the
writing may be subjective, as they are presented from our point of view, we
sincerely hope it will help the readers appreciate how extraordinary Su’s life
has been.

Figure 1: Ru-Keng Su, in 2007 at Zhang Jiajie, Hunan.

##  II Publications

Overall, Prof. Su has published more than 200 academic papers in prestigious
journals in physics, with a wide range of topics covering from the microscopic
particles to the immense universe. His research interest can be categorized
mainly into (1) nuclear and particle physics and (2) general relativity (GR)
and cosmology.

###  II.1 Nuclear and Particle Physics

Su explored various topics in intermediate and high energy nuclear physics and
particle physics, inclusively about the gauge fields [1], Higg mechanism [2,
3], soliton solutions and confinement [4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14,
15, 16, 17], and vacuum and fractional charge [18, 19, 20, 21]. Notably, Su is
well-known for his significant contributions to finite-temperature field
theory [22], embracing both the real-time [4, 23, 24, 7, 20, 25, 10, 26, 13,
27, 28, 29, 30, 31, 32, 33, 34, 35] and imaginary time [11, 12, 36, 37, 38,
16, 39, 40, 41] formalisms. Among others, these studies were primarily carried
out with his students Song Gao, Yi-Jun Zhang, Zhi-Xing Qian et al.

In [4], using generalized Bogoliubov transformation associated with the
coherent state, a kink-soliton solution in $(1+1)$ dimensional real $\phi^{4}$
theory is derived. The solution is interpreted as transitioning from a normal
to the superfluidity state triggered by a spontaneous symmetry breaking of the
vacuum state. Subsequently, the spectra of the underlying system at zero and
finite temperature are evaluated using the real-time Green function formalism.
The properties of the phase transition are elaborated, and as expected, the
symmetry is restored at higher temperatures from which the critical
temperature is derived. In [11], imaginary-time formalism is employed to
explore the non-topological solitons proposed by Friedberg and Lee [42, 43],
applied to the context of scalar soliton stars. This type of soliton is
triggered by the specific form of the effective potential and does not feature
a topologically non-trivial profile. By deriving the form of an effective
Lagrangian at finite temperature, the gravitational field equations are
derived and solved analytically under reasonable approximation. The physical
characteristics of the soliton star are evaluated and compared to those
obtained under mean-field scenarios and/or at vanishing temperatures.

Su’s main contributions to nuclear physics consist of studies primarily on the
effective models for nuclear and quark matter. They have explored topics such
as Coulomb instability [15, 44, 45, 46, 47], the speed of sound [48], hadrons
in medium [49], thermodynamics [50, 51, 52, 53], phase transition [54, 55] of
hadronic matter, and the quasiparticle models.

In [15], the Coulomb instability in hot nuclei is explored in the context of
the Skyrme model. As a self-consistent mean-field approach comprised of a
zero-range interaction with kinetic and density-dependent terms, the model is
a viable tool in investigating the nuclear structure and low-energy dynamics,
where collective correlations have been a priori built into the theoretical
framework. Utilizing finite-temperature real-time Green’s function, a detailed
analysis is carried out focusing on the stability in the low-temperature and
high-density regions of the system. The stability’s bound, the limit
temperature, is found to be approximately proportional to the critical
temperature. By comparing various models, it is also argued that the analysis
discriminates between different approaches. The liquid-gas phase transition in
the hadronic matter as a two-component system was explored in [54]. It was
found that the isospin degree of freedom plays a crucial role in the phase
transition of the underlying system. The phase diagram in the parameter space
regarding isospin asymmetry and concentration is significantly modified when
the interaction becomes isospin dependent. In particular, a “cut-off” feature
is observed, and the critical temperature in the original system is replaced
by a limit temperature. The latter, subsequently, gives rise to various
scenarios of phase transition regarding how the system is initially prepared.
The hadron properties [56, 57, 58, 59, 60, 61, 62, 62, 63], thermodynamics
[64, 65], and phase transition [47, 66, 67] of strange hadronic matter were
investigated. The studies were also performed for systems of quark degree of
freedom to scrutinize the thermodynamics [68, 69, 70, 71, 72] of quark matter,
and thermodynamics [73, 74, 75, 76, 77] of strange quark matter. The stability
conditions for strangelet and strange matter were closely analyzed.

Su has also made noticeable contributions to various relevant aspects of the
quasiparticle model, as well as the thermodynamic properties and consistency.
In [78], the role of an additional contribution to the thermal potential and
its consequential effect on the strange quark matter were explored. A series
of studies regarding the quark mass density- and temperature-dependent (QMDTD)
model was performed in [73, 74, 76, 70]. The temperature dependence of the
stable radius of a strangelet was discussed in [73]. The temperature
dependence of the bag constant $B$ was explored and shown to cure the
divergence that occurred at vanishing baryon density in the phase diagram for
the bulk strange quark matter of the original QMDTD model [74]. A systematic
analysis regarding the stability of strangelet was performed in [76] in the
framework of the QMDTD model. It was observed that stable strangelets are more
likely to be encountered in the region with a sizeable negative electric
charge and significant strangeness. The analysis was then extended to the
dibaryon systems [70] regarding different decay channels, and the results were
found in good agreement with those obtained by the chiral SU(3) quark model.
The QMDTD setup was then applied to the context of Friedberg-Lee soliton bag
[42, 43, 79] nonlinear coupled to the sigma [71] as well as omega [72] mesons.
The model was further extended to investigate the properties of deconfinement
[80, 72] and nuclear matter [81]. As an alternative approach to address the
thermodynamic consistency, an additional fictitious degree of freedom was
introduced [82, 83] to elaborate a generalized version of the first law of
thermodynamics. These works were primarily carried out in collaboration with
Hong-Qiu Song, as well as Su’s students Zhi-Xin Qian, Ping Wang, Yun Zhang,
Wei-Liang Qian, Li Yang, Chen Wu, and Shaoyu Yin.

###  II.2 General Relativity and Cosmology

In GR and cosmology, Prof. Su’s research was carried out mainly with his
students Rong-Gen Cai, Bin Wang, Cheng-Gang Shao, Li-Hui Xue, Da-Ping Du,
Weigang Qiu, Jian-Yong Shen, Songbai Chen, Qiyuan Pan, Shaoyu Yin, Chang Feng,
etc., along with other collaborators.

Prof. Su’s interest in GR and cosmology dates back to his early publications
after the Cultural Revolution. In several papers published in Chinese and
later in English, he discussed cosmological responses, gravitational
radiation, cosmological microwave background radiation, the open universe
model, Dirac’s cosmological model and large number assumption [84], Einstein-
Dirac equation, wormholes, higher-order gravitational theory, among others.
Though these publications primarily aimed to introduce the research frontier
to more Chinese readers, the selection revealed his insight, fast response,
and personal interest. Such work prepared him for innovative research in GR,
and some topics had long been among his favorite ones, which he dwelled on
throughout his research career.

Prof. Su’s formal research on GR started at a regular pace in 1992 with two
publications on black holes and wormholes [16, 85]. Since then, his research
has been carried out simultaneously on both sides of nuclear-particle physics
and the GR. Soon there was a big boost owing to the excellent collaboration
with Rong-Gen Cai, a doctoral candidate under the supervision of Prof. Su.
They studied various properties of different types of black objects, including
thermodynamics for dilaton black holes, neutral or charged [86, 87, 88], as
well as black strings and p-branes [89], phase transitions of black holes [90,
91], stability of Cauchy horizons [92], statistical mechanics [93] and Hawking
radiation [94] of BTZ black holes.

In this period, the most fruitful direction of their research is about the
thermodynamics and statistical properties of black objects. Prof. Su and his
collaborators successfully applied the Landau nonequilibrium fluctuation and
phase transition theory in discussing the phase transition of various types of
black holes. Specifically, the discussions of some divergent second moments
helped to clarify the nature of phase transitions [86, 90, 87, 91]. They also
showed particular interest in the dilaton black hole [86, 90, 87, 91], which
stems from string theory and has many interesting characters such as the
secondary hair [95] and unusual thermal properties [96, 97].

A second boost appeared when Bin Wang joined Prof. Su’s group as a doctoral
candidate and later as a permanent staff member. Then Prof. Su and Prof. Wang
formed a minority group in the Department of Physics at Fudan University,
where most of the teams focused on condensed matter, but their group remained
the most productive one as judged by their academic output. Their study on
black objects was continued and grew even more diversified and productive [98,
99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114,
115], and numerical simulation of quasinormal modes had also been developed
later [116, 117, 118, 119, 120, 121, 122, 123].

Meanwhile, their research topic extended to cosmology, with rich topics
including the influnce of particle process on cosmological evolution [124],
relation between the Cardy formula of entropy and the Friedmann equation in
the context of AdS/CFT duality for the (A)dS universes [125] as well as the
brane universes [126], quasi-normal modes of de-Sitter space-time [127],
tachyonic inflation [128], brane-world [129], curvature of the universe based
on supernova measurement [130], cosmological constant and dark sectors [131,
132, 133, 134, 135, 136], cosmic microwave background radiation [137],
modified gravity such as using the Dirac cosmology, which he favored all
along, to explain the accelerated expansion of contemprary universe [138] and
the $1/R$ gravity in the solar system tests [139], thermal effetc in inflation
[140], entanglement entropy in holographic models [141], etc. It can be
inferred from the publications’ titles that the scope of the research was not
limited to a thin branch. Generally speaking, a visible trend in their
research direction is to expand from the purely mathematical study, such as
the stability and geometry of black hole horizon in various dimensions of
space-time [98, 99, 100], to topics more related to actual observations. This
revealed their crucial value in keeping pace with the fast progress of
cosmology and positively and vigorously participating the international
competition. They did well, and their group became one of China’s most active
and prestigious research teams on GR and cosmology.

The collaboration between Su and Wang significantly contributed to the field
of black hole quasi-normal modes and the constraints on the cosmological
model. Among dozens of articles published in high-impact journals, several
most frequently cited works include testing the viability of the interacting
holographic dark energy model[135], where they utilized observational
constraints combining the latest gold type Ia supernova samples, Wilkinson
Microwave Anisotropy Probe observations, the baryon acoustic oscillation
measurement, $H(z)$ and lookback time measurements, the joint statistical
analysis provided the state-of-the-art testing of the interacting holographic
dark energy model contemporarily. They have also studied with a similar
approach the constraints on the dark energy from the holographic connection
the small $l$ CMB suppression [132], on dark energy from holography [131], on
the dark energy and dark matter mutual coupling [136], from which it can be
seen how Prof. Su’s group tried to catch up the academic frontier and to
compete with the world-leading research teams.

Prof. Su’s research on GR had some prominent characteristics. First of all,
taking advantage of his expertise in nuclear and high-energy physics, he could
make cross-field studies combining topics in GR with nuclear and particle
physics or utilizing the thermal field theory as a handy tool, such as in the
study of the scalar wormhole at finite temperature [142] and astrophysics of
compact objects involving both GR and nuclear/particle models [16, 143, 114].
Secondly, he encouraged students’ initiative and would like the abled students
to choose their favorite topics rather than simply make an assignment for
them. For instance, when Cheng-Gang Shao worked as a postdoc in Su’s group, he
studied gravitational test [139], slightly deviated from the mainstream of the
group’s research; while Li-Hui Xue, a student with excellent programming
skills contributed significantly in developing the numerical codes. As a
matter of fact, many new research branches in Su’s group were initialized by
some energetic students. However, it is worth emphasizing that, in all the
projects, Prof. Su always keeps pace with the progress and makes necessary
guidance with excellent insight. In Prof. Su’s group, there was always an
active and democratic atmosphere and open for any discussion. One of his
slogans is “I only worry about those of my students who do not dispute against
me”.

##  III Other Scientific Writings

Prof. Su authored several highly appreciated and widely used textbooks,
including “Quantum Mechanics” (first edition in 1997 by Fudan University
Press, second edition in 2002 by Higher Education Press), “Statistical
Physics” (first edition in 1990 by Fudan University Press, second edition in
2004 by Higher Education Press), “Advanced Quantum Mechanics” (English
version, co-authored with Bin Wang in 2004 by Fudan University Press), and
“Challenges in Physics - Selected Frontiers and Basic Topics of Physics” (in
1991 by Liaoning Education Press). He also translated A. Messiah’s “Quantum
Mechanics” (Volume 1, in collaboration with Jiayong Tang, published in 1986 by
Science Press).

##  Appendix A Life, Education, and Academic career

Born on May 27, 1938, Prof. Ru-Keng Su was a native of Shunde, a prosperous
town close to the Pearl (Zhujiang) River delta in the Guangdong Province of
China. Though he rarely talked about his childhood, it can be inferred that he
was born into a well-off family, as he suffered during the Cultural Revolution
due to his parentage. This explains the excellent education he received and
his exquisite taste in literature and classical Chinese poems. At eighteen, he
was admitted to Peking University, the top university in China, to study
Physics. Subsequently, he left the southern border of China and traveled to
the capital in the far north. The journey was uneasy for him at that time,
which took several days. He told us more than once very vividly how he took
the boat to cross the Yangtze river at Wuhan when the famous bridge crossing
the river had not been built yet and experienced distinct folk customs in
Central China.

Though harassed by continual political movements and limited food rationing
during that special period, Mr. Su won top-notch scores in his undergraduate
studies, despite the disturbance of coercive collective labor on farmland in
the daytime and volunteer work at night. Specially, Mr. Su had been working
extensively to assist Prof. Zhuxi Wang in composing a booklet of Concise
10-digit Logarithmic Tables as an offering to the first-decade celebration of
P. R. China. He used a rolling calculator, a state-of-the-art facility in
China then, while Prof. Wang double-checked his results using two abacuses.
His talent was recognized, and when he graduated in 1960, he was chosen to
work at Fudan University, a prestigious university in Shanghai. Since then, he
started his life there and contributed all his passion to teaching and
research in the Department of Physics at Fudan University for more than half-
century. He told us that on his first night in Shanghai, he wandered alone in
the university stadium under the bright mid-autumn moon, hungry and pondering
about his possible future at Fudan.

Prof. Su felt fortunate that he was assigned to the division of theoretical
physics, where he joined the research group of senior professor Shixun Zhou.
Prof. Su enthusiastically plucked himself into heavy teaching and research
tasks. Prof. Zhou composed a concise textbook on quantum mechanics, which
became popular in numerous Chinese universities in the 1960s. This inspired
Prof. Su to enrich the contents, notably more modern progress, and elaborate
his renowned Quantum Mechanics, which has become one of China’s most widely
adopted textbooks. Even during the difficult period, Su still managed to be
active in research for as long as possible, which brought him trouble and
punishment. Nevertheless, his optimism allowed him to be determined in his
research and pursue a valuable life, even if he was persecuted and forced to
take on unpleasant chores. After the 70s, his effort was rewarded,
demonstrated by the burst of publications. He was promoted to associate
professor in 1982, then to full professor in 1987, owing to his distinctive
achievements in teaching and research. Since 1987, Prof. Su has started to
serve as a Ph.D. supervisor.

Encouraged by Prof. Chen-Ning Yang, Fudan University established a local
research team on nuclear physics. The team was led by Prof. Fujia Yang, whose
members include, among others, Prof. Chaohao Gu and Prof. Daqian Li. As an
active team member, Prof. Su’s expertise and devotion were highly appreciated.
Subsequently, he was invited by Prof. Yang and visited the nuclear physics
research group at Stony Brook, New York State University, three times between
1984 and 1990. During his stay in the United States, Prof. Su also visited the
Institute of Nuclear Physics at the University of Washington in Seattle in
1985, where he collaborated with E.M. Henley. Besides, he visited the
Department of Physics and Astronomy, University of Kentucky, from September
1989 to February 1990. Prof. Su loved to tell the following story, especially
to those heading for the States to pursue their studies. Once, he had to
transfer in Chicago on a journey from Seattle to New York. Having heard of
violent crimes in the city, he was pretty worried about being robbed of his
hard-earned salary carrying with himself. Taking advice from some Chinese
fellows, he decided to wear a pair of sunglasses and a black overcoat with his
hands stuck in the pockets, forming the shape of a gun. Having camouflaged
himself in such an over-the-top stereotype of the local Chinese gangster and
strode defiantly through the crowd in public, Prof. Su arrived at his
destination safely and happily, with himself and the cash intact.

In the 1990s, he worked at the City University of Hong Kong for a couple of
years, where he made some good friends, including Prof. Jiju Xiao, who used
Prof. Su’s Quantum Mechanics as a textbook in his lessons. It was the first
Chinese physics textbook adopted in the university, extending its readership
beyond Mainland China. At the beginning of the 1990s, he was invited by Prof.
Tsung-Dao Lee and became a member of the advisory committee at the Chinese
Center of Advanced Science and Technology. As a reward for his academic
activity and support for the center, as well as a personal expression of
friendship, for many years, Prof. Su received greeting cards or books with
Prof. Lee’s paintings as New Year gifts.

##  Appendix B Notable status and awards

Given his academic achievement, Prof. Su had been elected as the vice-chairman
of the Chinese Society of High Energy Physics and a member of the Senate in
the Division of Mathematics and Physics of the National Natural Science
Foundation of China (NSFC). Prof. Su was also an active member of the Center
of Theoretical Nuclear Physics in the National Laboratory of Heavy Ion
Collisions in Lanzhou. In his public services, his integrity and insight were
highly appreciated by his colleagues and peers. Many junior scientists are
still grateful for the unbiased and unselfish support they received from him.

Su received three times the second prize for Scientific and Technological
Development issued by the Ministry of Education. He was awarded in 1988 for
“Vacuum stability, spontaneous symmetry breaking, and thermal field theory”
(in collaboration with Guang-Jiong Ni), in 1992 by “Theoretical research on
phase transition in nuclear matter at finite temperature and density”, and in
1996 by “Temperature field theory and its application in nuclear physics and
astrophysics”. In 1999, he won the second prize in the prestigious Natural
Science Award issued by the Chinese Academy of Science for “Critical phenomena
in nuclear systems and the effect of many-body correlation” (in collaboration
with Hongqiu Song). In 2003, he received the second prize in the Shanghai
Science and Technology Achievement Award for “Theoretical research of
holographic principle in black hole physics and cosmology” (in collaboration
with Bin Wang).

He has served on national boards of physics and astronomy foundations and
played a pivotal role in promoting the development of Chinese physics society.
In particular, he consistently served as a member of the core evaluation
committee of the National Natural Science Foundation of China (NSFC) and the
academic advisory committee of the China Center of Advanced Science and
Technology (CCAST).

##  Appendix C Miscellaneous contributions

Su’s interest in physics is not limited to the above topics in theoretical
physics. He also significantly contributed to science popularization in China,
fulfilling the vital task of making scientific knowledge understandable and
accessible to the lay public. Moreover, Su had also deeply indulged himself in
other fundamental problems in theoretical physics. Relevant topics include the
time arrow, negative temperature, hidden variables of quantum mechanics,
neutrino mass, the essence of light, coherent states, and the Klein paradox,
among others. He was not only among the first few Chinese physicists working
on finite-temperature field theory but also played a vital role in promoting
its usage by fellow Chinese physicists.

Besides scholastic publications, Su is well-known for his talent in classical
Chinese poems in the Chinese high-energy physics community. For a specific
period in the past, Su and his peers were accustomed to sending correspondence
in the form of poems to express their feelings about research and life. Su
later showed those pieces to the students who attended his lectures. He had
also published two reviews in the “Journal of Football” which, according to
some readers, demonstrated better logic than some experts of the sport.

##  Appendix D Teaching and orientations

Prof. Su had taught at Fudan University for more than half a century. His
lectures covered all major physics courses and contributed significantly to
the curriculum reform in Fudan. For undergraduate students, he lectured
“quantum mechanics”, “thermodynamics”, “statistical physics”, “classical
mechanics”, “modern physics”, “methods of mathematical physics”, among others.
For graduate students, he had given “advanced quantum mechanics”, “advanced
statistical physics”, “many body theory”, “frontiers in nuclear and particle
physics”, “quantum field theory”, “thermal field theory”, “general relativity
and cosmology”, “soliton and instanton”, “quantum field theory in curved
spacetime”. In 1999, his textbook “quantum mechanics” was awarded the first
prize in Shanghai Excellent Teaching Materials for Universities. He also
played a major role in tutoring students to prepare for CUSPEA, which
contributed significantly to the excellent scores won by the students from
Fudan.

Su was highly acclaimed for his humorous, passionate, and modern teaching
methodology. He was a prominent educator who cast a remarkable constructive
impact on his students. Students overwhelmingly adored him for his profound
insights and clear explanations and rated him as the most popular teacher at
Fudan for many successive years. Over the decades, tens of thousands of
students have listened to his lectures in person, while countless others have
studied following his textbooks and online video records.

Figure 2: Prof. Ru-Keng Su was well-known for his patent energy and expressive
body language in the classroom.

In 1993, Su was awarded the second prize in the Shanghai Excellent Teaching
Achievement Award for “constantly reforming teaching content and methods to
cultivate potential talents”. In 1999, he won the Baosteel Excellent Teacher
Award. In 2001, he won the second prize in the Shanghai Excellent Education
Achievement Award for “merging the frontier of science into didactic materials
and profound development of the pedagogy in teaching quantum mechanics”. In
2003, he won the Shanghai Teaching Master Award. As a part of the unique
collection of colleague physics materials (in collaboration with Qimin Jia and
Guangjiong Ni), his textbook won the first prize in Shanghai Excellent
Education Achievement Award and the second prize in National Teaching
Achievement Award; Soil" won the second prize of Shanghai Teaching Achievement
Award. In 2004, “quantum mechanics” was selected as a national premier course
for its excellency. In 2016, the Ministry of Education included it as part of
the first batch of “Public Courses of National Excellent Resource”. The
corresponding online course accumulated at least several hundred thousand
views. Many audiences claimed that Su’s energetic and charming teaching style
inspired their interest, helped them to understand esoteric quantum mechanics,
and even to pass the graduate school entrance exam.

Su cultivated eleven Ph.D. and dozens of masters and supervised hundreds of
undergraduate students. The Ph.D. students are Rong-Gen Cai (1995), Song Gao
(1995), Yi-Jun Zhang (1997), Bin Wang (1998), Ping Wang (1999), Yun Zhang
(2003), Wei-Liang Qian (2003), Wei-Gang Qiu (2005), Jian-Yong Shen (2008),
Chen Wu (2009), and Shaoyu Yin (2010). There also were three postdoctoral
fellows: Shuqian Ying (1993-1997), Cheng-Gang Shao (2004-2006), and Songbai
Chen (2006-2008). These students who have benefited from Su’s teaching are
engaged in various trades worldwide, and many are working at the front line of
scientific research and education. Su’s knowledge and spirit will continue to
be passed on and carried forward from generation to generation.

## References

  * [1] P.-C. Yin and R.-K. Su,  Guangzhou Conference on Theoretical Particle Physics (1980).
  * [2] G.-J. Ni and R.-K. Su,  (1980).
  * [3] G.-J. Ni, R.-K. Su, and S.-Q. Chen,  HEPNP 5, 429 (1981).
  * [4] R.-K. Su, P.-Z. Bi, and G.-J. Ni,  J. Phys. A 16, 2445 (1983).
  * [5] R.-K. Su and Y.-H. Zhang,  J. Phys. A 17, 851 (1984).
  * [6] R.-k. Su and Z.-Q. Ma,  J. Phys. A 19, 1739 (1986).
  * [7] R.-K. Su and X.-G. Gu,  J. Phys. A 19, 2891 (1986).
  * [8] G. E. Brown, H. Q. Song, R. K. Su, and K. F. Liu,  Nucl. Phys. A 458, 573 (1986).
  * [9] R.-K. Su and T. Chen,  J. Phys. A 20, 5939 (1987).
  * [10] R.-K. Su and Z. Hu,  Phys. Lett. A 141, 420 (1989).
  * [11] R.-K. Su and R.-S. Pan,  Phys. Lett. B 230, 99 (1989).
  * [12] R.-S. Pan and R.-K. Su,  Chin. Phys. Lett. 7, 1 (1990).
  * [13] R.-K. Su and Z. Hu,  Phys. Lett. A 147, 115 (1990).
  * [14] Y. G. Liang, B.-A. Li, K.-F. Liu, and R. K. Su,  Phys. Lett. B 243, 133 (1990).
  * [15] H. Q. Song and R. K. Su,  Phys. Rev. C 44, 2505 (1991).
  * [16] R.-S. Pan and R.-K. Su,  Phys. Rev. D 45, 2144 (1992).
  * [17] R.-K. Su, X.-L. Chen, and R.-S. Pan,  Chin. Phys. Lett. 9, 637 (1992).
  * [18] G.-J. Ni and R.-K. Su,  Phys. Lett. B 143, 437 (1984).
  * [19] Z.-Q. Ma, H. T. Nieh, and R.-K. Su,  Phys. Rev. D 32, 3268 (1985).
  * [20] R.-K. Su and T. Chen,  Phys. Lett. B 188, 469 (1987).
  * [21] R.-K. Su, Z.-Y. Yang, and T. Chen,  J. Phys. A 21, L593 (1988).
  * [22] R.-K. Su and P.-Z. Bi,  3rd Marcel Grossmann Meeting on the Recent Developments of General Relativity (1982).
  * [23] G. J. Ni and R.-k. Su,  (1984).
  * [24] R.-K. Su and P.-Z. Bi,  HEPNP 8, 177 (1984).
  * [25] T. Chen and R.-K. Su,  HEPNP 12, 140 (1988).
  * [26] R.-K. Su and F.-M. Lin,  Phys. Rev. C 39, 2438 (1989).
  * [27] R.-K. Su, Z.-X. Qian, and G.-T. Zheng,  J. Phys. G 17, 1785 (1991).
  * [28] R.-K. Su and Z.-X. Qian,  Phys. Rev. C 46, 1528 (1992).
  * [29] Z.-X. Qian, R.-K. Su, and C.-G. Su,  Phys. Rev. C 47, 877 (1993).
  * [30] Z.-X. Qian, R.-K. Su, and P. K. N. Yu,  Z. Phys. C 63, 651 (1994).
  * [31] S. Gao, R.-K. Su, and P. K. N. Yu,  Phys. Rev. C 49, 40 (1994).
  * [32] R.-K. Su, T. Long, and Y.-J. Zhang,  Phys. Rev. C 51, 1265 (1995).
  * [33] S. Gao, Y.-J. Zhang, and R.-K. Su,  Phys. Rev. C 52, 380 (1995).
  * [34] S. Gao, Y.-J. Zhang, and R.-K. Su,  Phys. Rev. C 53, 1098 (1996).
  * [35] S. Gao, Y.-J. Zhang, and R.-K. Su,  Chin. Phys. Lett. 13, 89 (1996).
  * [36] R.-K. Su and G.-T. Zheng,  J. Phys. G 16, 203 (1990).
  * [37] G.-T. Zheng and R.-K. Su,  HEPNP 14, 220 (1990).
  * [38] G.-T. Zheng and R.-K. Su,  HEPNP 14, 220 (1990).
  * [39] R.-K. Su, C.-G. Su, and R.-S. Pan,  Phys. Lett. B 278, 297 (1992).
  * [40] R.-K. Su, G.-T. Zheng, and G. G. Siu,  J. Phys. G 19, 79 (1993).
  * [41] S.-Z. Hu, S.-S. Cai, R.-K. Su, and G.-T. Zheng,  Chin. Phys. Lett. 10, 79 (1993).
  * [42] R. Friedberg and T. D. Lee,  Phys. Rev. D 15, 1694 (1977).
  * [43] R. Friedberg and T. D. Lee,  Phys. Rev. D 16, 1096 (1977).
  * [44] H. Q. Song, Z. X. Qian, and R. K. Su,  Phys. Rev. C 47, 2001 (1993).
  * [45] H. Q. Song, Z. X. Qian, and R. K. Su,  Phys. Rev. C 49, 2924 (1994).
  * [46] L. L. Zhang, H. Q. Song, P. Wang, and R. K. Su,  Phys. Rev. C 59, 3292 (1999).
  * [47] W. L. Qian, R.-K. Su, and H. Q. Song,  Phys. Lett. B 520, 217 (2001), arXiv:nucl-th/0107036.
  * [48] R. K. Su, H. Q. Song, and T. T. S. Kuo,  Phys. Rev. C 37, 1770 (1988).
  * [49] P. Wang and R.-K. Su,  Chin. Phys. Lett. 16, 793 (1999).
  * [50] Z.-X. Qian, H.-Q. Song, and R.-K. Su,  Phys. Rev. C 48, 154 (1993).
  * [51] L. Li, P. Wang, Y.-J. Zhang, S.-Q. Ying, and R.-K. Su,  J. Phys. G 25, 2297 (1999).
  * [52] P. Wang, Z.-W. Chong, R.-K. Su, and P. K. N. Yu,  Phys. Rev. C 59, 928 (1999).
  * [53] P. Wang, R. K. Su, H. Q. Song, and L. L. Zhang,  J. Phys. G 26, 11 (2000).
  * [54] W. L. Qian, R.-K. Su, and P. Wang,  Phys. Lett. B 491, 90 (2000), arXiv:nucl-th/0008057.
  * [55] W. L. Qian, R. K. Su, and H. Q. Song,  J. Phys. G 28, 379 (2002).
  * [56] L. L. Zhang, H. Q. Song, and R. K. Su,  J. Phys. G 23, 557 (1997).
  * [57] P. Wang, R. K. Su, H. Q. Song, and L. L. Zhang,  Nucl. Phys. A 653, 166 (1999).
  * [58] L. L. Zhang, H. Q. Song, P. Wang, and R. K. Su,  J. Phys. G 26, 1301 (2000).
  * [59] L.-L. Zhang, H.-Q. Song, P. Wang, and R.-K. Su,  Chin. Phys. Lett. 17, 874 (2000).
  * [60] P. Wang, R.-K. Su, H.-Q. Song, and L.-L. Zhang,  Commun. Theor. Phys. 35, 61 (2001).
  * [61] H. Q. Song, L. L. Zhang, P. Wang, and R. K. Su,  AIP Conf. Proc. 597, 98 (2001).
  * [62] P. Wang et al.,  Nucl. Phys. A 705, 455 (2002).
  * [63] H. Q. Song, R. K. Su, D. H. Lu, and W. L. Qian,  Phys. Rev. C 68, 055201 (2003).
  * [64] W.-L. Qian, R.-K. Su, and H.-Q. Song,  Commun. Theor. Phys. 40, 466 (2003).
  * [65] W. L. Qian, R.-K. Su, and H. Q. Song,  J. Phys. G 30, 1893 (2004), arXiv:nucl-th/0409063.
  * [66] L. Yang, W. L. Qian, R.-K. Su, and H. Q. Song,  Phys. Rev. C 70, 045207 (2004), arXiv:nucl-th/0311017.
  * [67] L. Yang, S. Y. Yin, W. L. Qian, and R.-k. Su,  Phys. Rev. C 73, 025203 (2006), arXiv:nucl-th/0506060.
  * [68] H. Q. Song and R. K. Su,  Phys. Lett. B 358, 179 (1995).
  * [69] H. Q. Song and R. K. Su,  J. Phys. G 22, 1025 (1996).
  * [70] Y. Zhang and R.-K. Su,  J. Phys. G 30, 811 (2004), arXiv:nucl-th/0304047.
  * [71] C. Wu, W. L. Qian, and R.-K. Su,  Phys. Rev. C 72, 035205 (2005), arXiv:nucl-th/0507012.
  * [72] C. Wu, W.-L. Qian, and R.-K. Su,  Phys. Rev. C 77, 015203 (2008), arXiv:0706.1349.
  * [73] Y. Zhang, R.-K. Su, S.-q. Ying, and P. Wang,  EPL 53, 361 (2001), arXiv:nucl-th/0203006.
  * [74] Y. Zhang and R.-K. Su,  Phys. Rev. C 65, 035202 (2002), arXiv:nucl-th/0201045.
  * [75] Y. Zhang and R.-K. Su,  (2002), arXiv:nucl-th/0203007.
  * [76] Y. Zhang and R.-K. Su,  Phys. Rev. C 67, 015202 (2003), arXiv:nucl-th/0207071.
  * [77] Y. Zhang and R.-K. Su,  Mod. Phys. Lett. A 18, 143 (2003).
  * [78] P. Wang,  Phys. Rev. C 62, 015204 (2000).
  * [79] R. Goldflam and L. Wilets,  Phys. Rev. D 25, 1951 (1982).
  * [80] H. Mao, R.-K. Su, and W.-Q. Zhao,  Phys. Rev. C74, 055204 (2006), arXiv:hep-ph/0606239.
  * [81] C. Wu and R.-K. Su,  J. Phys. G 36, 095101 (2009), arXiv:0809.2966.
  * [82] S. Yin and R.-K. Su,  Int. J. Mod. Phys. A 25, 1449 (2010), arXiv:0811.0483.
  * [83] S.-y. Yin and R.-K. Su,  Phys. Rev. C 77, 055204 (2008), arXiv:0801.2813.
  * [84] R.-K. Su and S.-W. Zhang,  (1982).
  * [85] Y.-G. Shen, R.-S. Pan, and R.-K. Su,  Sci. Sin. A 35, 991 (1992).
  * [86] R.-G. Cai, R.-K. Su, and P. K. N. Yu,  Phys. Rev. D 48, 3473 (1993).
  * [87] R.-G. Cai, R.-K. Su, and P. K. N. Yu,  Phys. Rev. D 50, 2719 (1994).
  * [88] R.-G. Cai and R.-K. Su,  Chin. Phys. Lett. 11, 526 (1994).
  * [89] R.-G. Cai, R.-K. Su, and P. K. N. Yu,  Phys. Lett. A 195, 307 (1994).
  * [90] R.-K. Su, R.-G. Cai, and P. K. N. Yu,  Phys. Rev. D 50, 2932 (1994).
  * [91] R.-G. Cai, R.-K. Su, and P. K. N. Yu,  Phys. Rev. D 52, 6186 (1995).
  * [92] R.-G. Cai and R.-K. Su,  Phys. Rev. D 52, 666 (1995).
  * [93] R.-G. Cai, R.-K. Su, and P. K. N. Yu,  Phys. Lett. A 199, 158 (1995).
  * [94] R.-G. Cai, Y.-J. Zhang, and R.-K. Su,  Chin. Phys. Lett. 12, 446 (1995).
  * [95] C. Wu, Y.-G. Ma, W.-L. Qian, and R.-K. Su,  Nucl. Phys. B378, 175 (1992).
  * [96] J. Preskill, P. Schwarz, A. Shapere, S. Trivedi, and F. Wilczek,  Mod. Phys. Lett. A 6, 2353 (1991).
  * [97] C. F. E. Holzhey and F. Wilczek,  Nucl. Phys. B390, 447 (1992).
  * [98] B. Wang and R.-K. Su,  Phys. Rev. D 53, 1950 (1996).
  * [99] B. Wang, R.-K. Su, and P. K. N. Yu,  Phys. Rev. D 54, 7298 (1996).
  * [100] B. Wang, R.-K. Su, and P. K. N. Yu,  Phys. Rev. D 58, 124026 (1998), arXiv:gr-qc/9801075.
  * [101] B. Wang, R.-K. Su, P. K. N. Yu, and E. C. M. Young,  Phys. Rev. D 57, 5284 (1998), arXiv:gr-qc/9802032.
  * [102] B. Wang and R.-K. Su,  Phys. Lett. B 432, 69 (1998), arXiv:gr-qc/9807050.
  * [103] B. Wang, R.-K. Su, and P. K. N. Yu,  Phys. Lett. B 438, 47 (1998), arXiv:gr-qc/9807053.
  * [104] B. Wang and R.-K. Su,  Phys. Rev. D 59, 104006 (1999), arXiv:gr-qc/9901085.
  * [105] B. Wang, E. Abdalla, and R.-K. Su,  Mod. Phys. Lett. A 14, 1329 (1999).
  * [106] B. Wang, E. Abdalla, and R.-K. Su,  Phys. Rev. D 62, 047501 (2000), arXiv:gr-qc/9911018.
  * [107] B. Wang, R.-K. Su, and E. Abdalla,  Int. J. Mod. Phys. A 16, 1367 (2001), arXiv:hep-th/0005043.
  * [108] W. Qiu, B. Wang, R.-K. Su, and E. Abdalla,  Phys. Rev. D 64, 027503 (2001).
  * [109] J.-y. Shen, R.-G. Cai, B. Wang, and R.-K. Su,  Int. J. Mod. Phys. A 22, 11 (2007), arXiv:gr-qc/0512035.
  * [110] W.-J. Mo, R.-G. Cai, and R.-K. Su,  Commun. Theor. Phys. 46, 453 (2006).
  * [111] S. Chen, B. Wang, and R.-K. Su,  Phys. Lett. B 647, 282 (2007), arXiv:hep-th/0701209.
  * [112] S. Chen, B. Wang, and R.-K. Su,  Phys. Rev. D 77, 024039 (2008), arXiv:0710.3240.
  * [113] S. Chen, B. Wang, R.-K. Su, and W. Y. P. Hwang,  JHEP 03, 019 (2008), arXiv:0711.3599.
  * [114] S. Yin, J. Zang, and R.-K. Su,  Eur. Phys. J. A 43, 295 (2010), arXiv:0908.0235.
  * [115] S. Yin et al.,  Phys. Rev. D 82, 064025 (2010), arXiv:1004.4244.
  * [116] L.-H. Xue, B. Wang, and R.-K. Su,  Phys. Rev. D 66, 024032 (2002), arXiv:hep-th/0205267.
  * [117] L.-H. Xue, Z.-X. Shen, B. Wang, and R.-K. Su,  Mod. Phys. Lett. A 19, 239 (2004), arXiv:gr-qc/0304109.
  * [118] Z.-X. Shen, B. Wang, and R.-K. Su,  Chin. Phys. Lett. 21, 428 (2004), arXiv:gr-qc/0307097.
  * [119] D.-P. Du, B. Wang, and R.-K. Su,  Phys. Rev. D 70, 064024 (2004), arXiv:hep-th/0404047.
  * [120] C.-G. Shao, B. Wang, E. Abdalla, and R.-K. Su,  Phys. Rev. D 71, 044003 (2005), arXiv:gr-qc/0410025.
  * [121] J.-y. Shen, B. Wang, and R.-K. Su,  Phys. Rev. D 74, 044036 (2006), arXiv:hep-th/0607034.
  * [122] J. Shen, B. Wang, C.-Y. Lin, R.-G. Cai, and R.-K. Su,  JHEP 07, 037 (2007), arXiv:hep-th/0703102.
  * [123] Q.-Y. Pan and R.-K. Su,  Commun. Theor. Phys. 55, 221 (2011).
  * [124] R.-K. Su, Z.-X. Qian, B. Wang, P. K. N. Yu, and E. C. M. Young,  Nuovo Cim. B 113, 385 (1998).
  * [125] B. Wang, E. Abdalla, and R.-K. Su,  Phys. Lett. B 503, 394 (2001), arXiv:hep-th/0101073.
  * [126] B. Wang, E. Abdalla, and R.-K. Su,  Mod. Phys. Lett. A 17, 23 (2002), arXiv:hep-th/0106086.
  * [127] W.-G. Qiu, B. Wang, and R.-K. Su,  Chin. Phys. Lett. 19, 1587 (2002).
  * [128] B. Wang, E. Abdalla, and R.-K. Su,  Mod. Phys. Lett. A 18, 31 (2003), arXiv:hep-th/0208023.
  * [129] D.-P. Du, B. Wang, E. Abdalla, and R.-K. Su,  Int. J. Mod. Phys. A 19, 4085 (2004), arXiv:hep-th/0312087.
  * [130] B. Wang, Y.-g. Gong, and R.-K. Su,  Phys. Lett. B 605, 9 (2005), arXiv:hep-th/0408032.
  * [131] B. Wang, E. Abdalla, and R.-K. Su,  Phys. Lett. B 611, 21 (2005), arXiv:hep-th/0404057.
  * [132] J.-y. Shen, B. Wang, E. Abdalla, and R.-K. Su,  Phys. Lett. B 609, 200 (2005), arXiv:hep-th/0412227.
  * [133] Z.-Y. Huang, B. Wang, R.-G. Cai, and R.-K. Su,  Chin. Phys. Lett. 23, 2621 (2006), arXiv:astro-ph/0511745.
  * [134] Z.-Y. Huang, B. Wang, and R.-K. Su,  Int. J. Mod. Phys. A 22, 1819 (2007), arXiv:astro-ph/0605392.
  * [135] C. Feng, B. Wang, Y. Gong, and R.-K. Su,  JCAP 09, 005 (2007), arXiv:0706.4033.
  * [136] C. Feng, B. Wang, E. Abdalla, and R.-K. Su,  Phys. Lett. B 665, 111 (2008), arXiv:0804.0110.
  * [137] Z.-Y. Huang, B. Wang, E. Abdalla, and R.-K. Su,  JCAP 05, 013 (2006), arXiv:hep-th/0501059.
  * [138] C.-G. Shao, J.-y. Shen, B. Wang, and R.-K. Su,  Class. Quant. Grav. 23, 3707 (2006), arXiv:gr-qc/0508030.
  * [139] C.-G. Shao, R.-G. Cai, B. Wang, and R.-K. Su,  Phys. Lett. B 633, 164 (2006), arXiv:gr-qc/0511034.
  * [140] S. Yin, B. Wang, and R.-K. Su,  Phys. Lett. B 675, 84 (2009), arXiv:0810.3465.
  * [141] R.-G. Cai, L. Li, L.-F. Li, and R.-K. Su,  JHEP 06, 063 (2013), arXiv:1303.4828.
  * [142] R.-S. Pan, R.-K. Su, and C.-G. Su,  Chin. Phys. Lett. 12, 261 (1995).
  * [143] J.-y. Shen, Y. Zhang, B. Wang, and R.-K. Su,  Int. J. Mod. Phys. A 20, 7547 (2005), arXiv:gr-qc/0503015.