Timeline for Gravitons with negative mass?
Current License: CC BY-SA 3.0
6 events
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| Nov 10, 2017 at 4:38 | comment | added | Bob Bee | I can't remember the exact number, I posted on it a few days after and it is one part in about $10^{15}$. You can also see the same numbers in a LIGO papaer on it. The 1.7 seconds is from threshold to threshold, but the calculations added more time because of the uncertainty of the model of when the gamma rays were produced. But yes, they did use some model results also. So, not exact but the number is still pretty amazing. Even 100 seconds would still be the same speed with the exponent being 13. The graviton mass limits were also calculated but some model dependency also. | |
| Nov 9, 2017 at 15:41 | comment | added | LostCause | We need to be very precise because 1.7 light seconds is a bigger distance than the distance between earth and moon. Nevertheless, these types of detection help us correct our understanding of science. | |
| Nov 9, 2017 at 15:37 | comment | added | LostCause | @BobBee I think you are talking about the recent neutron stars collision. Don't think your numbers are correct. The collision happened 130 million light-years away. The gravitational wave signal lasted about 100 secs. And our Fermi gamma-ray telescope identified gamma rays 1.7 sec later. Now, if gravitational waves travel slower, then why did we observe the light after the waves? I think we need precise calculation on how long does it take for light to emerge after the gravitational wave is created and then go from there. | |
| Nov 9, 2017 at 1:08 | comment | added | Bob Bee | The theory has long been considered. The first experimental result is from the recent kilonova detection which saw gravitational waves and EM waves only 1.2 sec later, over a distance of more than a billion light years. That is the same speed to within 1 part in about $10^{15}$, indeed a nice limit on the graviton mass. | |
| Nov 8, 2017 at 17:18 | history | edited | LostCause | CC BY-SA 3.0 |
added 344 characters in body
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| Nov 8, 2017 at 17:11 | history | answered | LostCause | CC BY-SA 3.0 |