Timeline for Why do photons add mass to a black hole?
Current License: CC BY-SA 3.0
8 events
| when toggle format | what | by | license | comment | |
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| Oct 20, 2012 at 0:36 | vote | accept | Argus | ||
| Aug 21, 2012 at 19:10 | comment | added | Argus | To expand on my "soft" understanding the photon does not hit the eh just the backup of material created by the eh. Does the same increase occur if the photon crosses the eh "un-interrupted" not yet quite far enough to prove GR mute when would the momentum effect the BH as soon as it passes the eh or is there a certain point were the energy becomes part of the BH. | |
| Aug 21, 2012 at 14:39 | comment | added | John Rennie | You're quite correct of course. Put it down to old age and impending senility. | |
| Aug 21, 2012 at 14:36 | comment | added | Alan Rominger | I don't even understand how you can be unsure, if a photon hits the event horizon it will increase the mass of the BH. I don't understand where there is room for skepticism. Photons have no rest mass but they can impart mass onto other things. If this were about a particle of ordinary matter, a fully absorbed photon would impart mass through increased KE plus heat energy. In the case of a BH taken to be stationary, photon hitting at CM, there is no KE change, and 100% of the photon's energy adds to the BH mass. I'm baffled b/c you're the expert of the 2 of us! | |
| Aug 21, 2012 at 14:31 | history | edited | John Rennie | CC BY-SA 3.0 |
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| Aug 21, 2012 at 14:27 | comment | added | John Rennie | @alanse: I didn't say you could measure a different inertia from gravitational mass, I said I wasn't sure if you would. Having said that, you're quite right of course because even though photons are massless they have a momentum. I was just suffering a temporary brain fade. Thanks for the injection of sanity :-) | |
| Aug 21, 2012 at 14:02 | comment | added | Alan Rominger | The first part of your answer is a gem, but I was quite taken aback by the statement that you could measure a different $\Delta M$ from the gravitational field created and the inertia. Wasn't this equivalency the entire point of GR? I'm sitting here thinking "no way that's what he meant". My understanding would be completely wrong about everything if that's true. | |
| Aug 21, 2012 at 9:03 | history | answered | John Rennie | CC BY-SA 3.0 |