Part A. PERSONAL DATA

A.1 Current Professional Status

Institution: University of Valencia

Department: Theoretical Physics (Faculty of Physics) and IFIC (Joint UV-CSIC Center)

Professional Category: Full Professor

UNESCO Code: 2212 Theoretical Physics

Keywords: Quantum field theory, electroweak theory, QCD, and Higgs physics. Theories beyond the Standard Model: Dual and string theories

A.2 Academic Background

Degree: Bachelor of Science in Physics, University of Valencia (1981)

Degree: Doctor of Philosophy in Physics, University of Valencia (1985)

A.3 General Indicators of Scientific Production Quality

• Number of six-year research periods: 6 (last six-year period 2012-2017)

• Field of Scientific Activity: Theoretical Physics (Dual and string theories. Theory and phenomenology of elementary particles and their interactions.)

• Research Associate at the Rutherford Laboratory (U.K.) from 1986 to 1991.

• Publications: approximately 75 articles in journals indexed in the SCI (Physical Review, Physical Review Letters, JHEP, Nuclear Physics, Astrophysical Journal, Europhysics Letters, etc.).

• Total citations (Inspire Hep): 1240

• Hours: 21

• Award from the Royal Academy of Exact and Physical Sciences (1985).

A4. General Academic Indicators

4.1. Teaching Service Periods: 6

4.2. Teaching Evaluation Results:

Evaluation of activity through the DOCENTIA program (2015–2020): 189/200

Annual evaluation reports (2019–2024). Average: 4.45

4.3. Management Positions Held (in the past).

Head of the Department of Theoretical Physics: one term.

Secretary of the Department of Theoretical Physics: three terms.

Coordinator of International Relations for Physics for eleven years.

Part B. CURRICULUM VITAE SUMMARY

ORCID Code: 0000-0002-0511-271X

Fields within Theoretical Physics in which I have developed activities whose results are published in international journals.

• Theories beyond the Standard Model (from 2000 to the present and future project). Work carried out with Professors H. M. Chan (Rutherford Lab.) and T. S. Tseung (University of Oxford), along with doctoral students and other occasional collaborators. 35 publications.

Contribution: Development of a theory of elementary particles beyond the Standard Model (Framed Standard Model or FSM) that aims to address some outstanding theoretical problems, such as the hierarchy of fermion masses and mixtures, or "strange" experimental results recently observed in particle physics. During the period indicated, an exhaustive study of the model was conducted, comparing it with experimental data without, so far, finding any contradictions. The results have led to approximately fifty publications and conference presentations.

• Summation rules in Quantum Chromodynamics (1986-89 and 2000-10). This work was carried out with Professors C. Domínguez (University of Cape Town), F. Schilcher (University of Mainz), J. A. Peñarrocha, and V. Giménez (University of Valencia), along with doctoral students and other occasional collaborators. 17 publications. Based on general properties of the two-point correlation function, relationships are established between its asymptotic expansion at high energies and its imaginary part in the domain of hadronic physics.

Novel contribution: Introduction of the finite-energy Laplace summation rule to estimate quark-gluon condensates, heavy quark masses (charm and bottom), decay constants of mesons containing b or s quarks, and other problems related to low-energy hadronic physics.

• String and superstring field theory (1986–2001). Work carried out with Professors H. M. Chan (Rutherford Lab.) and T. S. Tseung (University of Oxford), along with doctoral students and other occasional collaborators. 18 publications.

Novel Contribution 1 (1986-90): Discretization of strings. Treatment of functional integrals through string discretization and numerical calculation of interaction amplitudes.

Novel Contribution 2 (1991-2001): Interpretation of the interaction in string theory by applying the original half-string overlap mechanism to (non-polynomial) string field theory, identifying the parameter space in the different channels as well as the transition region between them, which does not appear in an explicit formulation using Feynman diagrams and must be explicitly included at each order.

Novel Contribution 3: Description of the theory using half-string oscillators (“commas”). Calculation of amplitudes and study of formal aspects of string theory in this formulation, particularly suitable for the formulation of a field theory.

• Two-photon physics in the lepton-hadron collision (1981-85). 3 publications and subject of the Doctoral Thesis. Study of the electromagnetic interaction beyond the one-photon exchange approximation by calculating the two-photon exchange interaction in the lepton-nucleus collision predicted by QED.

Contribution: treatment of the hadronic continuum that depends on characteristic magnitudes of the hadronic structure.

• Parity violation in atoms (1981 and 87). 2 publications and subject of the Bachelor's Thesis. Study of electroweak couplings between quarks and leptons at energies typical of the atomic structure by analyzing atomic transitions sensitive to the mixing of parity-defined states induced by neutral currents.

Novel contribution: introduction of nuclear spin in the study of parity violation-sensitive electromagnetic transitions in muonic atoms.

Part C. MOST RELEVANT MERITS.

C.1. Ten most interesting publications (in my opinion).

1. J. Bordes, H. M. Chan and S. T. Tsou, “A vacuum transition in the FSM with a possible new take on the horizon problem in cosmology”, Int. J. Mod. Phys. A 38 (2023) no. 25, 2350124 doi:10.1142/S0217751X23501245
2. J. Bordes, H. M. Chan and S. T. Tsou, “Unified FSM treatment of CP physics extended to hidden sector giving (i) δCP for leptons as prediction, (ii) new hints on the material content of the universe,” Int. J. Mod. Phys. A 36 (2021) no.31n32, 2150238 doi:10.1142/S0217751X21502389
3. J. Bordes, H. M. Chan and S. T. Tsou, “Accommodating three low-scale anomalies (g-2, Lamb shift, and Atomki) in the framed standard model,” Int. J. Mod. Phys. A 34 (2019) no.25, 1950140 doi:10.1142/S0217751X19501409
4. J. Bordes, H. M. Chan and S. T. Tsou, “Generation patterns, modified γ−Z mixing, and hidden sector with dark matter candidates as framed standard model results,” Int. J. Mod. Phys. A 33 (2019) no.36, 1830034 doi:10.1142/S0217751X1830034X
5. S. Bodenstein, J. Bordes, C. A. Dominguez, J. Penarrocha and K. Schilcher, “Bottom quark mass from finite energy QCD sum rules,” Phys. Rev. D 85 (2012), 034003 doi:10.1103/PhysRevD.85.034003
6. J. Bordes, H. M. Chan and S. T. Tsou, “A Dynamical mechanism for quark mixing and neutrino oscillations,” Eur. Phys. J. C 10 (1999), 63-70 doi:10.1007/s100529900092
7. J. Bordes, H. M. Chan, J. Faridani, J. Pfaudler and S. T. Tsou, “Possible test for the suggestion that air showers with E > 10**20-eV are due to strongly interacting neutrinos,” Astropart. Phys. 8 (1998), 135-140 doi:10.1016/S0927-6505(97)00039-X
8. J. Bordes, H. M. Chan, L. Nellen and S. T. Tsou, “HALF STRING OSCILLATOR APPROACH TO STRING FIELD THEORY,” Nucl. Phys. B 351 (1991), 441-473 doi:10.1016/0550-3213(91)90097-H
9. J. Bordes and F. Lizzi, “Computation of Amplitudes in the Discretized Approach to String Field Theory,” Phys. Rev. Lett. 61 (1988), 278 doi:10.1103/PhysRevLett.61.278
10. J. Bordes, “E(6) Signatures in Atomic Physics,” Phys. Lett. B 190 (1987), 97 doi:10.1016/0370-2693(87)90846-X

C.2. Participation in R&D&I Projects

• Participation in projects funded by the Spanish Ministry of Education and Science (or equivalent at the time) and the EU from 1981 to the present in the field of “Elementary Particles: The Standard Model and its extensions”. Currently with reference PID2023-151418NB-I00 MCIU/AEI/10.13039/501100011033/FEDER.
• Participation in PROMETEO projects funded by the Valencian Regional Government from 2002 to the present in the field of “Particle Physics and their interactions”. Currently with reference PROMETEO CIPROM/2022/36.
• Member of IFIC, Severo Ochoa Center. Currently with reference CEX2023-001292-S.
• Participation in the UVEG innovation project in the period 2009-2015: Virtual Laboratory of Chemical Physics.

[Biography, english version]

[Biography, english version]

Scientific Career:

In 1987-88, I was a postdoc at Carnegie Mellon University, Pittsburgh (USA). In 1989-90, I was a postdoc at the Max Planck Institute for Physics in Munich, Germany. In 1989, I obtained a tenured position as Associate Professor at the University of Valencia through a competitive examination. From 1992-94, I held a CERN fellowship at CERN, Geneva, Switzerland. In 2007, I obtained the qualification for Full Professor through a competitive examination, and since 2008, I have been a Full Professor at the University of Valencia.

Research lines and key contributions:

1. Quantum Corrections in the Standard Model:
   Various results have been obtained in this area, but perhaps the most significant is the discovery of the non-decoupling effects of the top quark in the Z-b-b interaction. This result was published at the time and was essential in determining the top quark mass at LEP before its discovery at Fermilab (Bernabéu, Pich & Santamaria).

2. Massive Neutrinos:
   Recently, we have confirmed that neutrinos do indeed have mass. However, there is still no “standard model of massive neutrinos.” It is therefore crucial to develop a model capable of describing all experimental data and that can be tested in the future. In this field, we have published several high-impact articles proposing and studying different models to explain the small neutrino masses (with Bertolini, Valle, Nebot, Oliver, Palao, del Águila, Bhattacharya, Aparici, Wudka, Herrero-Garcia, Rius, Das, Alcaide).

3. Higgs Boson Physics in the Standard Model and Its Extensions:
   The Higgs boson has finally been discovered at the LHC, and exploring its properties is crucial. We have been working in this area for some time. We studied the possibility of the Higgs boson decaying invisibly into other scalars (Bertolini & Santamaria). Recently, CMS and ATLAS reported hints of Higgs decays violating lepton flavor, and we have thoroughly explored this possibility (Herrero-Garcia, Rius & Santamaria). We have also analyzed the scalar mass spectrum in a model with scalar triplets, considering the known properties of the Higgs boson (Das & Santamaria).

4. Tau Lepton Physics:
   A phenomenological resonance model was developed to describe tau lepton decays into two and three pions, which has been widely used (Kühn & Santamaria). Additionally, the magnetic moment of the tau lepton was determined using experimental data from LEP (Gonzalez-Springer, Santamaria & Vidal).

5. Particles in Astrophysics:
   In this field, aside from implications for specific models, a key contribution was the systematic study of new neutrino interactions in supernova cooling (Choi & Santamaria).

    

6. Effective Quantum Field Theories (EFTs):
   We have studied, in general, the use of EFTs to analyze new physics (Bilenky & Santamaria) and to simplify the calculation of radiative corrections in renormalizable theories (Peris & Santamaria). In recent years, we have also used EFTs to describe neutrino masses in the most model-independent way possible (del Águila, Aparici & Wudka).

7. Theories with Extra Dimensions:
   We have analyzed the quantum effects of additional dimensions in the decay of the Z boson into b quarks (Oliver, Papavassiliou & Santamaria). Additionally, we have studied the calculability of quantum effects that grow with energy in such models. Controlling these effects is essential for constructing a theory that unifies all interactions at experimentally accessible energy scales (Oliver, Papavassiliou & Santamaria).

8. Mass Running and QCD:
   In quantum field theories, mass appears as another parameter of the theory, almost at the same level as coupling constants. As such, it is not a fixed quantity but varies with energy. However, until recently, the variation of mass with energy had never been experimentally verified. A key milestone was suggesting that the LEP experiment might have the necessary precision to test the energy dependence of the b quark mass (Bilenky, Rodrigo & Santamaria). This verification required highly complex calculations by our group and a sophisticated experimental analysis carried out by the DELPHI collaboration in Valencia (Fuster et al.). Thanks to this collaboration between theoretical and experimental groups in Valencia, we can now confirm that quark masses evolve with the energy scale.

Degree in Physics from the University of Valencia, July 1993. PhD in Physics from the University of Valencia, September 1997.

Postdoctoral appointments at Brookhaven National Laboratory, New York (February–August 1998); EU Marie Curie fellowship at SISSA, Trieste (Italy) from September 1998 to September 2000; Marie Curie reintegration grant at the University of Valencia from October 2000 to October 2001; European research network appointment at the University of Oxford from October 2001 to November 2003; and Fellow at CERN from January 2004 to December 2005.

Ramón y Cajal contract at the University of Valencia from December 2005 to December 2008. Associate Professor at the University of Valencia from December 2008 to October 2025. Full Professor since November 2025.

Supervision of five PhD theses.