Maximum gravity

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>[Rudolf]: what's the current explanation or list of explanations for 'gamma ray bursts' events? I recall reading black hole evaporation as one but since they don't exist...?<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

The association with supernovas for at least some gamma ray bursts is looking pretty strong in recent data.

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>What is the status of LIGO?<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

Operational but not seeing anything yet.


<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>[123]: Isn't the Cherenkov radiation considered a "shock wave" of the electromagnetic type? It seems that any situation in which a source travels faster than the medium, "shock waves" are produced in the medium (the waves in the medium get bunched since it can't get ahead of the source of the disturbance). Thus theoretically, gravitational "shock waves" would be produced if 1) gravitational waves exist, and 2) some source causing disturbances in the gravitational medium is traveling faster than the speed limit of the gravitational waves.<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

True enough. We can see Cherenkov radiation, although have not seen its effects on material surrounding the source.

Of course, the waves themselves are still constrained to propagate at the wave speed of the medium. For Cherenkov radiation, just as for a jet exceeding the speed of sound, only the source (e.g., the jet) travels faster than the wave speed. That can create a large number of bunched-up waves all traveling together at the normal wave speed. (A sonic boom from a jet plane is like that, traveling at the speed of sound, and therefore comes from the direction where the jet was, not where it is now.)

Anyway, I suppose one could get gravitational waves arriving all bunched together in this way. In general, whatever can happen to radio waves usually can happen to gravitational waves too. But anything producing Cherenkov radiation is more likely to produce high-energy waves than low-energy waves. This suggests the thought that gamma ray bursts might be the "sonic booms" from supernova explosions. -|Tom|-

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>
[tvf]
... gamma ray bursts might be the "sonic booms" from supernova explosions.
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? Photonic boom ?

LB

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>

Anyway, I suppose one could get gravitational waves arriving all bunched together in this way. In general, whatever can happen to radio waves usually can happen to gravitational waves too. But anything producing Cherenkov radiation is more likely to produce high-energy waves than low-energy waves. This suggests the thought that gamma ray bursts might be the "sonic booms" from supernova explosions. -|Tom|-


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I think the energy of the wave produced would more likely depend on what the medium is composed of. Electromagnetic disturbances in water might appear blue (e.g. Cherenkov radiation) but if done in a different medium, say chlorine for example, the "photonic boom" observed might come out green..purple...red....silver..anything from microwave to yray.

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote> Tom - The association with supernovas for at least some gamma ray bursts is looking pretty strong in recent data.<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

Some types of supernovas are associated with things like neutron stars and other collapsed objects. Since these objects are already extremely dense I just wonder if not part of the reason is linked to the idea I had. Perhaps when the white dwarf/neutron star/'black hole' have accumulated enough material from the binary neighbor some phase change occurs triggering the explosion which might be in part because of a gravitational collapse?

I also wonder about the directional component of 'events'? What I mean is simply what would cause a burst to travel in our specific direction? Or, does it expand radially or spherically?

Rudolf

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>[Rudolf]: I just wonder if not part of the reason is linked to the idea I had.<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

Collisions? The time scale is too slow for those -- minutes to hours.

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>Perhaps when the white dwarf/neutron star/'black hole' have accumulated enough material from the binary neighbor some phase change occurs triggering the explosion which might be in part because of a gravitational collapse?<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

Same problem with explosions. If Earth exploded, it would not be at all as seen in "Star Wars". A blast wave traveling outward at 20 km/sec would take five mintes to travel from Earth's center to its surface.

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>I also wonder about the directional component of 'events'? What I mean is simply what would cause a burst to travel in our specific direction? Or, does it expand radially or spherically?<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

Directed events are supposed to be caused by relativistic jets, which is a stretch. Any theory that can explain an event with an isotropic flux is sure to be more plausible. -|Tom|-

Thanks for the explanations.

Are there any publicly available papers on 'Gamma ray burst' events or collisions of massive objects on the Internet?

Rudolf