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Astronomers Find Brightest Pulsar Ever Observed
An anonymous reader writes: Astronomers using the Chandra X-ray Observatory and the NuSTAR satellite have discovered a pulsar so bright that it challenges how scientists think pulsars work. While observing galaxy M82 in hopes of spotting supernovae, the researchers found an unexpected source of X-rays very close to the galaxy's core. It was near another source, thought to be a black hole. But the new one was pulsing, which black holes don't do. The trouble is that according to known pulsar models, it's about 100 times brighter than the calculated limits to its luminosity (abstract). Researchers used a different method to figure out its mass, and the gap shrank, but it's still too bright to fit their theories.
I don't find their hypothesis very persuasive. They don't go into any details. How exactly is this mechanism supposed to work? How high luminosities should be expected? What limits on pulse rates does their model predict? How is the energy generated? How large are pulsars? If they aren't compact objects, why do we have pairs of them that are separated by half the diameter of the sun?
If the standard model of pulsars were held to the same stnadard of handwaviness, one wouldn't even have discovered that there might be a problem with a too high luminosity for this pulsar. You only discover that sort of problems once you actually get down to it and calculate the consequences of your model. Examples of predictions made by the neutron star model of pulsars is: Pulsars should have quite well-defined maximum and minimum masses, and maximum and minimum sizes and surface gravities. They can't be too light, or they wouldn't collapse to form neutron stars, they would be white dwarves instead. And they can't be too heavy, or they would collapse to form black holes. These upper and lower bounds are called the Chandrasekhar limit (1.4 solar masses) and Tolman–Oppenheimer–Volkoff limit (about 3 solar masses). If the neutron star is to stay together it can't rotate so fast that the centrifugal force wins over gravity. This, together with the limits on surface gravity and diameter implies a maximum rotation frequency. All pulsars we have seen so far fit with these limits.
The reason why a too high luminosity is considered problematic is that the energy source of ultraluminous pulsars is belived to be accretion: Matter falling down towards the surface of the neutron star, and converting lots of potential energy into kinetic energy and then heat radiation as it does so. But if too much radiation is emitted, this radiation exerts a pressure on the infalling matter that is so great that it pushes the matter back out. So if the pulsar (or any other thing driven by accretion) gets too bright, it ends up starving itself, and can't stay brighter than the point where radiation exactly cancels gravity for very long. That limit is called the Eddington limit, and the problem in this case is that the pulsar is 100 times brighter than this limit.
You can get around the Eddington limit by allowing for an asymmetric infall: More matter falling from some directions than other directions (example: a meteor hitting the earth is asymmetric accretion). But it's hard to go all the way up to 100 times the Eddington limit with realistic accretion scenarios. So this really is an interesting object.
But my point is that the Electric Universe guys don't do anything to explain the power source of the pulsar. If one assumes that it is powered by accretion as in the standard model, then they have exactly the same problem as the standard model. And if it isn't powered by accretion, where does it get its energy from? The article you link to talks about emission mechanisms, but not where the energy comes from in the first place. Also, the link they give to the press release is about a variant on the standard neutron star picture - it does not support the Electric Pulsar hypothesis.
Think about the way the moon causes the liquid part of the earth to stretch in the directions both exactly toward the moon and exactly away from it.
Nothing's stretching away. In order of distance from the Moon we have:
1) nearside oceans
2) the Earth itself
3) farside oceans
All of them are attracted towards the Moon, but at decreasing strength due to distance. The nearside ocean gets pulled closer to the Moon than the Earth does, and the Earth gets pulled closer to the Moon than the farside ocean does. Hence, two bulges, but not because the far one is being pushed away from the Moon.
However, you've got that other star circling around the black hole - stretching it into an oval shape.
When you say "it," do you mean the star or the black hole? It seems like you mean the black hole...
A black hole isn't a physical object. It's a surface around an object at which the gravitational field strength has a particular value. I'm not sure it would be influenced in such a way by the presence of another object.
then perhaps the distortion of the gravity field is sufficient such that it allows the light to escape
What light are you talking about?
systemd is Roko's Basilisk.