Talk detail

Participant	Xue, She-Sheng
Institution	ICRANet - Piazzale della Repubblica, - Pescara - Abrruzo - Italy

Session	SF1-2	Accepted	Yes	Order	4	Time	15:30	15'
Talk	Oral abstract	Title	Gravitational and electricenergies in gravitational collapses
Coauthors	Ruffini Remo
Abstract	We discuss in gravitational collapses how gravitational energy is converted to both kinetic and electric energies in form of electron-positron-photon plasma. It is shown that (i) averaged kinetic and electric energies are the same order, about an half of gravitational energy of stellar cores in collapse; (ii) caused by radiating and rebuilding electric energy, gravitational collapse undergoes a sequence of ``on and off'' hopping steps in the microscopic Compton scale, and it is slowed down as kinetic energy is reduced and collapsing time becomes longer.
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Session	DE1	Accepted	Yes	Order	13	Time	18:25	15'
Talk	Oral abstract	Title	How universe evolves with cosmological and gravitational constants (Nucl. Phys. B in press)
Coauthors
Abstract	We study a regularized and quantized Einstein-Cartan gravitational field theory and its domains of ultraviolet-unstable fixed point $g_{\rm ir}\gtrsim 0$ and ultraviolet-stable fixed point $g_{\rm uv}\approx 4/3$ of the gravitational gauge coupling $g=(4/3)G/G_{\rm Newton}$. Because the fundamental operators of quantum gravitational field theory are dimension-2 area operators, the cosmological constant is inversely proportional to the squared correlation length $\Lambda\propto \xi^{-2}$. The correlation length $\xi$ characterizes an infrared size of a causally correlate patch of the universe. The cosmological constant $\Lambda$ and the gravitational constant $G$ are related by a generalized Bianchi identity. As the basic space-time cutoff $\tilde\ell$ decreases and approaches to the Planck length $\ell_{\rm pl}$, the universe undergoes inflation in the domain of the ultraviolet-unstable fixed point $g_{\rm ir}$, then evolves to the low-redshift universe in the domain of ultraviolet-stable fixed point $g_{\rm uv}$. We give the quantitative description of the low-redshift universe in the scaling-invariant domain of the ultraviolet-stable fixed point $g_{\rm uv}$, and its deviation from the $\Lambda$CDM can be examined by low-redshift $(z\lesssim 1)$ cosmological observations, such as supernova Type Ia.
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