
Giant magnetic ropes seen in Whale Galaxy's halo - dnetesn
https://phys.org/news/2019-12-giant-magnetic-ropes-whale-galaxy.html
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DiabloD3
It's pretty cool they've been able to discover and image galactic Birkeland
currents. Alfvén's work predicted that such things exist and, sadly, he didn't
live long enough to see today's cosmologists continue his work.

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flareback
How do they get an image of the magnetic fields?

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gattr
By measuring polarization of the received radio-frequency signals. The
polarization is affected by magnetic fields ("Faraday rotation", see [0, 1]).

[0]
[https://en.wikipedia.org/wiki/Faraday_effect#In_the_interste...](https://en.wikipedia.org/wiki/Faraday_effect#In_the_interstellar_medium)

[1] [https://www.mpifr-
bonn.mpg.de/research/fundamental/cosmag](https://www.mpifr-
bonn.mpg.de/research/fundamental/cosmag)

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EddieCPU
What does this mean for the long term evolution of galaxies, no need for dark
matter?

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pfdietz
No. The forces on stars from galactic magnetic fields are insignificantly
small.

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zyxzevn
Strong magnetic fields in galaxies are very common.
[http://scholarpedia.org/article/Galactic_magnetic_fields](http://scholarpedia.org/article/Galactic_magnetic_fields)

But there is a huge problem with them. Like Alfven, I am against the idea of
frozen magnetic fields. Frozen fields were invented to explain how magnetic
fields can exist, without the need for electric currents. At that time they
thought that space was a very good isolator. Thanks to laboratories and
satellites we now know different.

With my background in electromagnetism, I have to go one step further: frozen
fields are physically impossible. The papers and text-books about them show
false usage of induction laws. As if magnetism behaves like a current, like in
a waveguide with electromagnetic waves. Sadly this is completely false.
Induction in gasses or plasma behave a bit like those in a fluid, and they
disperse the magnetic field. A bit like eddy currents. That is also what we
see in our laboratories.

But magnetic fields can easily be caused by electric currents instead, because
any electric current creates a magnetic field. This field is stronger when we
measure closer to the current. So we can get very strong magnetic fields as we
see inside young galaxies. Link: [https://www.discovermagazine.com/the-
sciences/weirdly-strong...](https://www.discovermagazine.com/the-
sciences/weirdly-strong-magnetic-field-in-young-galaxy-perplexes-astronomers)
So we have electric plasma currents, instead of "magnetic ropes". Like in our
laboratories. But I am not sure whether the community is ready to accept
that..

Instead of the dynamo model, strong electric currents can easily come from
nuclear explosions. These have been reported, but due to the secrecy they are
not openly reported. Just a magnetic field can create a homopolar dynamo in an
electric current. Currents are usually circular, but in a large space and very
high speeds, the charge can take a long time to come around. It will be very
interesting to actually measure the scale at which these occur.

Now if we have a black-hole like object in the centre of a galaxy, that spews
out matter into 2 main directions. Because it also has a magnetic field, it is
very likely that this matter has a certain charge. So this creates a current
in the galaxy, which also generates the magnetic field. This how I think the
magnetic field is generated.

The strength of these electric currents is in the order of 1/R, where R is the
distance travelled. That is because currents are usually concentrated into one
direction, like lightning, and only resistance hinders it. Magnetic objects
encounter a force of 1/R^4 because magnetic objects have 2 poles. So these
electric currents can transfer energy over very long distances.

As this matter-beam reaches the edge of the galaxy, it will turn around and go
back to the galaxy. And because it has some charge, it will create a
polarizing field in the halo.It would be interesting to see if there is also
some sustained charge in these halos.

[https://fermi.gsfc.nasa.gov/science/constellations/pages/bub...](https://fermi.gsfc.nasa.gov/science/constellations/pages/bubbles.html)
I suspect that the Fermi bubbles might have an opposite charge.

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mathiasrw
This is no surprise if you follow the wave of evidence for the electrical
universe model. It puts electricity and magnetism as the main shaping force of
the universe while considering gravity a negligible influence.

Look on youtube. Lots of good material.

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fsloth
Look... the are bunch of us here who recieved a scientific training. While we
don't claim that science can explain _everything_ at the moment, we do claim
that there are a lot of crackpots out there with appealing ideas but zero
capability of explaining them in a credible fashion.

For some reason these crackpot theories appeal to people who feel for one
reason or other that they are "missing something". Then charismatic
personalities gravitate towards these communities and spin out yarn that feels
right to the specific people listening to them creating a belief. _Feels
right_ and _belief_ are the keywords here. There is no proof that would
withstand rigorous criticism.

With science, you should love your pet theory, put also put the hard labour in
to prove it. And if your testing creates evidence to the contrary, you should
be cognitively able to abandon it.

These crackpot theorists start from their pet theory, don't actually study
physics or what ever their theory is about, and spend all the effort in
spinning yarn about how great their theory is, instead of actually proving it.

If you want to learn about actual physics, there is great introduction lecture
series by Leaonard Susskind called "The theoretical minimum":

[https://www.youtube.com/playlist?list=PL47F408D36D4CF129](https://www.youtube.com/playlist?list=PL47F408D36D4CF129)

Grab a pencil and paper and start watching :) !

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erikpukinskis
I’m not sure I understand what you’re trying to say... that you have put in
the effort and you are confident in your analysis that this “electrical
universe” hypothesis is not well formed?

I think it’s a bit disingenuous to give a long, vague treatise on crackpots in
response to an actual human being, without directly addressing them.

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8bitsrule
I "recieved [sic] a scientific training" as well, and I choose not to call
people names for trying out new ideas. Given the state of cosmology these
days, all the questions and recent and unexplained phenomena, an open mind
towards new hypotheses (yes, _and_ encouraging following them up with tests
... in a non-snide way) is important.

"The suppression of uncomfortable ideas may be common in religion or in
politics, but it is not the path to knowledge, and there's no place for it in
the endeavor of science. We do not know beforehand where fundamental insights
will arise from.... Fundamental insights can arise from the most unexpected
sources." \- Sagan

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bananabreakfast
There is an ocean of difference between being open to new ideas and just
letting any new concept get your equal mindshare without a compelling reason
like evidence.

There is a reason no one that is respected talks about these "crackpot" ideas.
The established ideas are here because they survived decades of trying to be
proved wrong but they survive since they fit observed nature. New ideas are
just that: new.

When someone introduces a new type of database HN doesn't say "why won't
people take new ideas with an open mind??", they say "SQL works and has been
proven. You have to prove your new idea is better before I'll use it."

Exact same concept.

