Gareth Samuel Malfunctioning Electric Stars Thunderbolts

Technical Ladder
47 followers
1 Video View·Nov 4, 2022
Gareth Samuel Malfunctioning Electric Stars Thunderbolts
Pulsars are mysterious objects that emit electromagnetic radiation in a clockwork-like
fashion. The period of this pulsing can be extremely short. Back in 1967, Jocelyn Bell
Burnell, using a newly commissioned radio telescope, discovered a very strange signal.
It was initially dismissed as radio interference by her supervisor,
but continued observations showed that it appeared at the same declination and right ascension
which ruled out a terrestrial source of interference. They eventually were able to
resolve the signal as a series of pulses, evenly spaced every 1.33 seconds. At the time,
no astronomical object of that nature had ever been observed. Speculation as to the origin of
the signal started to grow, with some even suggesting that the signal might be beamed
to Earth from extraterrestrial intelligence. In December of the same year, she managed to
discover a second pulsar and ruled out the idea of it being a signal from ETs.
In 1968, Thomas Gold suggested that pulsars were highly magnetised, rapidly rotating neutron stars.
This model required a high-energy plasma beam to be emitted from the poles of a spinning neutron
star and accelerated along the star's dipole magnetic field, emitting radiation as pulses
towards the observer, like the sweeping lights from a lighthouse. Since then, many more pulsars
have been observed and the shortest pulse ever detected was a staggering 1.4 milliseconds.
Where does the neutron star come from and why does it rotate so fast?
The mainstream idea is that these objects are the remnants of a supernova explosion.
The central region of the star collapses, crushing together every proton and electron
into a neutron. The dense core of the star is all that is left. The angular momentum of the
original star is conserved, meaning the much smaller object has to rotate at an incredible
speed. The only way for those beams to be produced is in the presence of a very strong magnetic field.
But all we have are neutrons. The origin of the critically strong magnetic field
required for their model is therefore unclear. To add to these problems, a new pulsar has been
discovered which seems to rewrite a lot of these ideas. The pulsar had one of the slowest pulse
rates ever seen at 76 seconds. Most are between a few seconds down to milliseconds. Apart from
the unexpected pulse rate, it also seems to reside in what scientists call the neutron star
graveyard. This is a region of space where they don't expect to detect any radio emissions at all.
This is because they theorise that neutron stars here are at the end of their life cycle
and therefore not active. It is also unique as it appears to produce at least 7 distinctly
pulse shapes, whereas most neutron stars don't exhibit much variety.
This makes it hard for them to explain using their model of a rotating beam.
One particular type of pulse shows a strong quasi-periodic structure.
This suggests that a type of oscillation is driving the radio emissions.
This is a large clue to understanding what causes the pulses in the pulsar.
Anthony Peratt and Kevin Healy have proposed a completely different mechanism,
which would not require a fast spinning plasma beam but instead utilise the known properties
of transmission lines. This is similar to the way planetary magnetospheres are described.
If the star is surrounded by a disk of plasma then it is likely that it is electromagnetically
coupled to the magnetosphere via field-aligned currents. In a lossless line with perfect
n-conductors the pulses propagate back and forth forever. In reality the kinetic energy
of the relativistic current flowing along the guide magnetic field is lost in synchrotron
radiation. Any disturbance on a transmission line such as an arc discharge or an interruption of
steady state condition results in initiation of travelling waves, which propagate towards
the ends of the line, where they may be reflected and modified, attenuated and distorted by any
losses until they die out. Field-aligned current pulses propagate at high latitudes along the
dipole magnetic field. Two regions of high-density plasma terminate this magnetospheric transmission
line, plasma near the pulsar surface and plasma at the disk. The transmission line may also contain
a double layer. This structure forms a torus and the relativistic current pulses propagate within
a toroid waveguide. The pulsar's magnetospheric transmission line can be modelled by two current
conducting boundaries that represent the inward and outward field-aligned currents. The line is
terminated by two conductors, the pulsar surface and the disk. A voltage pulse is launched from
the pulsar surface. This ends up being reflected back, which changes its polarity. In both simulations
and experiments carried out by Peratt and Healy, they saw both single and double pulse profiles.
When they included the effects of plasma flowing between the current boundaries,
some important modifications were observed. As the electric field propagates along the line,
electrons accelerate away from the boundary. Due to the intense magnetic field associated
with the current pulse, they are constrained to flow along the E x B drift rather than across
the line. This means that the entire line acts as a continuous source of low-level radiation and noise.
All pulsars show this background radiation. Whether the radiated pulse has a single or
double pulse profile will depend on the extent of the radiation region at the pulsar surface.
If the radiating current is confined to a shallow region instead of an extended region,
a single pulse profile will replace the double profile. This effect is actually frequency
dependent. Lower frequencies are associated with fields that are extended in the emission region
and are more likely to show pulse structure. The source of the radiation energy is not contained
within the pulsar, but may instead derive from either the pulsar's interaction with its environment
or by energy delivered by an external circuit. This means that pulsars do not have to be composed
of neutrons. They are simply no different to a normal star. What has changed is its electrical
environment causing a resonance in the circuit which creates the pulses. In the distant past,
this star might have suffered a catastrophic short circuit. So violent is the discharge that
is not only creating heavier elements in the process but also explodes the entire surface
double layer. With nothing to hold back the charges, the majority of the material that
made up the star races outwards in an explosion. In some cases, a remnant remains after this process.
The electrical power input continues to drive the magnetospheric circuit to produce the
characteristic pulsar emissions. No neutrons, no spinning beams, simply a star that has changed
its electrical environment causing a resonance in its circuit which creates the pulses.
