3,415 research outputs found
Lorentz invariance violation from GRB221009A
The Large High Altitude Air Shower Observatory~(LHAASO) reported observation
of photons with energies above 10~TeV from gamma ray burst GRB221009A. A
suggestion was proposed that this result may contradict with our knowledge of
special relativity~(SR) and the standard model~(SM), according to which photons
of about 10~TeV from such a distant object should be severely suppressed
because of the absorption by extragalactic background light. As a result, a
number of mechanisms have been proposed to solve this potential puzzle,
including Lorentz invariance violation~(LIV). In this work, we perform a
detailed numerical calculation and show the feasibility to constrain LIV of
photons from the LHAASO observation of GRB221009A quantitatively.Comment: 6 pages, 1 figur
Revisiting Lorentz invariance violation from GRB 221009A
As a potential consequence of Lorentz invariance violation~(LIV), threshold
anomalies open a window to study LIV. Recently the Large High Altitude Air
Shower Observatory~(LHAASO) reported that more than 5000 photons from GRB
221009A have been observed with energies above 500~GeV and up to
. In the literature, it is suggested that this observation may
have tension with the standard model result because extragalactic background
light~(EBL) can prevent photons around 18~TeV from reaching the earth and that
LIV induced threshold anomalies might be able to explain the observation. In
this work we further study this proposal with more detailed numerical
calculation for different LIV scales and redshifts of the sources. We find that
GRB 221009A is a rather unique opportunity to search LIV, and a LIV scale
is
feasible to the observation of GRB 221009A on 9 October, 2022.Comment: 10 pages, 7 figures, final version for journal publicatio
Quantum phase transitions in a two-dimensional quantum XYX model: Ground-state fidelity and entanglement
A systematic analysis is performed for quantum phase transitions in a
two-dimensional anisotropic spin 1/2 anti-ferromagnetic XYX model in an
external magnetic field. With the help of an innovative tensor network
algorithm, we compute the fidelity per lattice site to demonstrate that the
field-induced quantum phase transition is unambiguously characterized by a
pinch point on the fidelity surface, marking a continuous phase transition. We
also compute an entanglement estimator, defined as a ratio between the
one-tangle and the sum of squared concurrences, to identify both the
factorizing field and the critical point, resulting in a quantitative agreement
with quantum Monte Carlo simulation. In addition, the local order parameter is
"derived" from the tensor network representation of the system's ground state
wave functions.Comment: 4+ pages, 3 figure
Constraint on Lorentz invariance violation from Vela pulsar
The High Energy Stereoscopic System (H.E.S.S) Collaboration reported the
discovery of a novel radiation component from the Vela pulsar by their
Cherenkov telescopes. It is of great importance that gamma rays with energies
of at least 20~TeV are recorded unexpectedly. The H.E.S.S Collaboration argued
that such results may challenge the state-of-the-art models for the high-energy
emission of pulsars. We point out in this work that these results also provide
a unique opportunity to constrain certain Lorentz invariance violation
parameters, leading to the realization of studying Lorentz invariance violation
by using gamma-ray pulsars. The Lorentz invariance violation scale is
constrained at the level of for
the linear scenario, and for the
quadratic scenario. We anticipate that digging into the detailed features of
the data of the Vela pulsar and analyzing potentially more very-high-energy
photon data from pulsars in the future would improve the constraints on Lorentz
invariance violation.Comment: 2 pages, no figur
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