Statistical Significance of Lorentz invariance violation from GRB 160625B

Ganguly, S and Desai, Shantanu (2017) Statistical Significance of Lorentz invariance violation from GRB 160625B. arXiv. pp. 1-6. (Submitted)

[img]
Preview
Text (arXiv copy)
1706.01202.pdf - Accepted Version

Download (372kB) | Preview

Abstract

Recently Wei et al (arXiv:1612.09425) have found evidence for a transition from positive time lags to negative time lags in the spectral lag data of GRB 160625B. They have fit these observed lags to a sum of two components: an intrinsic time lag due to astrophysical mechanisms and an energy-dependent speed of light due to violation of Lorentz invariance, which could be a signature of quantum gravity. Here, we examine the statistical significance of the evidence for this claim using the same data by comparing it against the null hypothesis, viz. the time-lags are induced only by intrinsic delays. We use three different model comparison techniques: a frequentist test and two information based criteria (AIC and BIC). From the frequentist model comparison test, we find that evidence for Lorentz violation is favoured at 3.05σ and 3.74σ for linear and quadratic models respectively and do not cross the 5σ discovery threshold. We find that ΔAIC and ΔBIC have values ≳ 10 for the quadratic Lorentz violating model pointing to "decisive evidence" against Lorentz invariance violation compared to only astrophysically induced intrinsic emission. Another concern however is that none of the three models (including the null hypothesis) provide a good fit to the data, which implies that there is additional physics or systematic errors, which are not accounted for while fitting the data to these models.

[error in script]
IITH Creators:
IITH CreatorsORCiD
Desai, Shantanuhttp://orcid.org/0000-0002-0466-3288
Item Type: Article
Subjects: Physics > Astronomy Astrophysics
Depositing User: Team Library
Date Deposited: 12 Jun 2017 05:10
Last Modified: 05 Sep 2017 06:16
URI: http://raiith.iith.ac.in/id/eprint/3206
Publisher URL:
Related URLs:

Actions (login required)

View Item View Item
Statistics for RAIITH ePrint 3206 Statistics for this ePrint Item