1. Full name: Do Thu Ha                                                2. Sex: Female

3. Date of birth: 01/05/1986                                4. Place of birth: Hai Duong

5. Admission decision number: Number 3035/QĐ-ĐHKHTN, date 22/08/2016 by University of Science, Viet Nam National University.

6. Changes in academic process: Extension decision number 567/QĐ-ĐHKHTN, date 14/02/2020; Extension decision number 318/QĐ-ĐHKHTN, date 01/02/2021.

7. Official thesis title: Straight line approximation for high-energy scattering processes in quantum gravity theory

8. Major: Theoretical Physics and Mathematical Physics             9. Code: 9440130.01

10. Supervisors: Professor. Doctor of Science. Nguyen Xuan Han           

11. Summary of the new findings of the thesis

- Obtain the scattering cross section of the particle on two external potentials, namely the Gauss potential and the Yukawa potential.

- Obtain a linear trajectory representation for the scattering amplitude for the Newtonian potential, including the contribution of relativistic correction and quantum correction from the one-loop diagram in the effective quantum gravity theory.

- Obtain the straight orbital expression for the scattering amplitude and its complement term using the quasipotential method in coordinate representation within the framework of linear quantum gravity theory.

- The novelty and difference of the above results compared to previous studies is that we have combined relativistic effects and quantum effects in gravitational scattering to clarify part of the relationship between effective quantum field theory of general relativity and relativistic quantum mechanics. Specifically:

+ The relativistic correction term is calculated from non-analytical contributions and is explained as the result of "zitterbewegung" vibrations when the distance between particles is shifted by an amount equal to the length of a Compton wavelength. This contribution is related to particle nonlocality. If a particle has mass, it cannot be localized in a volume with linear dimensions less than the Compton wavelength of the corresponding particle, in other words - the concept of particle coordinates in the usual sense of the word is complete. completely meaningless.

+ The quantum correction term related to Planck's constant is also found. This is a new result and needs to be considered more specifically at the Planck energy level when taking into account higher order loop corrections.

12. Paratical applicability, if any: The results obtained in the thesis, on the basis of approximating straight orbits using a series of different approaches, are the basis for continuing to study the gravitational scattering problem as well as unifying four types of interactions: electromagnetic interaction, weak interaction, strong interaction and gravitational interaction.

13. Further research directions, if any: Attractive interactions, Unifying the four types of interactions.

14. Thesis-related publications:

[1]. N. S. Han, D. T. Ha, and N. N. Xuan (2019), “The contribution of effective quantum gravity to the high energy scattering in the framework of modified perturbation theory and one loop approximation”, European Physical Journal C, Vol. 79, No. 10, pp. 835-847.

[2]. D. T. Ha (2020), “High Energy Scattering Amplitude in The Linearized Gravitational Theory”, Scientific Journal of Hanoi Metropolitan University, Vol. 39, pp. 49-54.

[3]. C. T. Vi Ba, D. T. Ha, N. N. Xuan, and D. D. Thanh (2022), “Functional Integral Method for Potential Scattering Amplitude in Quantum Mechanics”, VNU Journal of Science: Mathematics - Physics, Vol. 38, No. 4, pp. 45-60.

[4]. D. T. Ha and N. T. Huong (2023), “The High Energy Scattering Amplitude in The One - Loop Effective Gravitation Field Theory”, VNU Journal of Science: Mathematics – Physics, Vol. 39, No. 4, pp. 64-70.