I apologize, but I couldn't find any information about Prof. Ali Abdulla or their specific views on stars and quantum tunneling. It's possible that the reference you mentioned is not widely known or might be specific to a particular context or discussion.
However, I can provide a general explanation regarding the role of quantum tunneling in nuclear reactions, such as the formation of deuterium in stars.
Quantum tunneling is a phenomenon in quantum mechanics where a particle can pass through a potential barrier even if it does not possess enough energy to surmount that barrier classically. This effect arises due to the wave-like nature of particles at the quantum level.
In the context of nuclear reactions in stars, such as nuclear fusion, quantum tunneling plays a crucial role in enabling certain processes to occur. For example, in the core of a star, protons (hydrogen nuclei) collide with each other and need to overcome the electrostatic repulsion between them to fuse and form deuterium (a stable bound state of a proton and a neutron).
Quantum tunneling allows some protons to overcome this electrostatic barrier by passing through it, despite not having sufficient energy to do so classically. Through the process of tunneling, these protons can enter a region where the attractive nuclear force between the protons and neutrons can bind them together, resulting in the formation of deuterium.
It's worth noting that stars are not purely quantum mechanical systems at macroscopic scales. However, the behavior of particles within stars, including the processes involved in nuclear fusion, can be accurately described using quantum mechanics due to the microscopic nature of particles and the influence of quantum effects at that scale.
If you have any other questions or need further clarification, please let me know.