NASA's Fermi gamma-ray space telescope. has observed high-energy photons arriving up to 20 minutes behind smaller low-energy ones from a source 12 billion light years away. Why the Lag?
Mark
Question on Gamma Ray Time Lags
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Question on Gamma Ray Time Lags
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Re: Question
Source?mark swain wrote:NASA's Fermi gamma-ray space telescope. has observed high-energy photons arriving up to 20 minutes behind smaller low-energy ones from a source 12 billion light years away.
http://asterisk.apod.com/vie ... =8&t=17555
Re: Question
Many times source events just take that long or longer. A gamma-ray burst (GRB), which I believe is the source here, can keep emitting gamma rays for over an hour after the initial photons get emitted.
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Re: Question
Thanks for the link. That clears things up a bit. I believe the galaxy Markarian 501 gamma-ray measurement occurred in 2005. There is later data that, I believe, better confines quantum gravity-related dispersion with GRBs. Please see:
http://arstechnica.com/science/news/200 ... -burst.ars
http://arstechnica.com/science/news/200 ... -burst.ars
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Re: Question
Quantum gravity theories wiped out by a gamma ray burst, Oh dear.
Hey, maybe Quantum Gravity, decided 'It' was going to fool us.
Thanks for the interesting link RJN.
Mark
Hey, maybe Quantum Gravity, decided 'It' was going to fool us.
Thanks for the interesting link RJN.
Mark
Always trying to find the answers