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arXiv · 1912.00900

Significantly super-Chandrasekhar mass-limit of white dwarfs in noncommutative geometry

Surajit Kalita·Banibrata Mukhopadhyay·T. R. Govindarajan
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Abstract

Chandrasekhar made the startling discovery about nine decades back that the mass of compact object white dwarf has a limiting value, once nuclear fusion reactions stop therein. This is the Chandrasekhar mass-limit, which is $\sim1.4M_\odot$ for a non-rotating non-magnetized white dwarf. On approaching this limiting mass, a white dwarf is believed to spark off with an explosion called type Ia supernova, which is considered to be a standard candle. However, observations of several over-luminous, peculiar type Ia supernovae indicate that the Chandrasekhar mass-limit to be significantly larger. By considering noncommutativity among the components of position and momentum variables, hence uncertainty in their measurements, at the quantum scales, we show that the mass of white dwarfs could be significantly super-Chandrasekhar and thereby arrive at a new mass-limit $\sim 2.6M_\odot$, explaining a possible origin of over-luminous peculiar type Ia supernovae. The idea of noncommutativity, apart from the Heisenberg's uncertainty principle, is there for quite sometime, without any observational proof however. Our finding offers a plausible astrophysical evidence of noncommutativity, arguing for a possible second standard candle, which has many far-reaching implications.

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Surajit Kalita, Banibrata Mukhopadhyay, T. R. Govindarajan. 2019-11-26. Significantly super-Chandrasekhar mass-limit of white dwarfs in noncommutative geometry. https://doi.org/10.1142/s0218271821500346

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