according to Newton gravity and GR a star with mass exceeding the Chandrasekhar limit collapses to a point and mass density becomes infinite, what is nonsense and shows the limit of especially GR.. A new formulation of W.Greiner an collaborators has been given, which avoids this problem.
please comment.
The discussion around the Chandrasekhar limit and the collapse of stars into singularities touches upon the edges of our current understanding of physics, particularly within the realms of general relativity (GR) and quantum mechanics. The Chandrasekhar limit specifically refers to the maximum mass (about 1.4 times the mass of the Sun) that a stable white dwarf star can have. Beyond this limit, the star is believed to collapse into a neutron star or a black hole, depending on its mass, due to the gravitational force overcoming electron degeneracy pressure.
so, going back to General Relativity;
as we know, it predicts the formation of singularities under certain conditions, such as in the centers of black holes where, theoretically, density and gravity become infinite ( whether it actually can exist or not is a matter for another discussion..)
This prediction is often considered a sign that the theory breaks down under extreme conditions, because the notion of an "infinite" physical quantity does not make practical sense and because GR does not incorporate quantum mechanics, which is essential for describing the universe at very small scales.
in my view, the mention of W. Greiner and collaborators refers to efforts to reformulate our understanding of gravitation and stellar collapse in a way that avoids these singularities. Walter Greiner was a prominent physicist known for his work in various areas, including heavy ion physics and quantum electrodynamics. While I don't know the latest specifics of his work or related theories, the general endeavour I assume involve integrating principles of quantum mechanics with general relativity to arrive at a more complete theory of quantum gravity.
Several approaches to quantum gravity, such as string theory and loop quantum gravity, aim to provide a framework where the singularities predicted by general relativity are resolved or avoided. These theories suggest that at very small scales, the fabric of spacetime becomes quantized, and thus the traditional concept of a singularity, where matter is infinitely dense, is replaced by a scenario where quantum effects dominate, potentially avoiding infinite densities.It's crucial to acknowledge that while general relativity and quantum mechanics are extremely successful in their respective domains, their unification into a single coherent theory remains the current Holy grail. Any proposal, like that of Greiner and his collaborators, may represents a step towards this ultimate goal, and would be subject to rigorous scrutiny, experimentation, et al.
I don’t find it particularly satisfying explanation at present
Greiner's paper is certainly not the solution. nevertheless it s a very interesting ansatz.
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