Thursday, January 7, 2010

Magnetic Universe



"The example of the magnet I have hit upon is a very pretty one, and entirely suited to the subject; indeed, it is little short of being the very truth." -- Johannes Kepler, astronomer/mathematician, 1609

"It is therefore plausible, since the Earth moves the moon through its species and magnetic body, while the sun moves the planets similarly through an emitted species, that the sun is likewise a magnetic body." -- Johannes Kepler, astronomer/mathematician, 1609

"But come: let us follow more closely the tracks of this similarity of the planetary reciprocation [libration] to the motion of a magnet, and that by a most beautiful geometric demonstration, so that it might appear that a magnet has such a motion as that which we perceive in the planet." -- Johannes Kepler, astronomer/mathematician, 1609

There is a giant magnet at the center of the Milky Way. It is the "black hole" in the logic, or rather lack thereof, of gravitation.

Science Daily: Center of Milky Way's Magnetic Attraction Ten Times Stronger Than Rest of Galaxy.

ScienceDaily (Jan. 7, 2010) — An international research project involving the University of Adelaide has revealed that the magnetic field in the centre of the Milky Way is at least 10 times stronger than the rest of the Galaxy.

The evidence is significant because it gives astronomers a lower limit on the magnetic field, an important factor in calculating a whole range of astronomical data.

Researchers from the Max-Planck-Institute for Nuclear Physics, the University of Adelaide, Monash University and the United States have recently published their findings in Nature.

Dr Roland Crocker, the lead author, and Dr David Jones both worked on the project while based at Monash University and the University of Adelaide's School of Chemistry and Physics. The two physicists are now based at the Max-Planck-Institute for Nuclear Physics in Heidelberg, Germany.

"This research will challenge current thinking among astronomers," Dr Crocker says. "For the last 30 years there has been considerable uncertainty of the exact value of the magnetic field in the centre of the Milky Way. The strength of this field enters into most calculations in astronomy, since almost all of space is magnetised," he says.

Dr Jones says the findings will affect diverse fields, from star formation theory to cosmology.

"If our Galactic Centre's magnetic field is stronger than we thought, this raises additional questions of how it got so strong when fields in the early universe are, in contrast, quite weak. We know now that more than 10% of the Galaxy's magnetic energy is concentrated in less than 0.1% of its volume, right at its centre," he says.

Dr Jones completed his PhD at Adelaide, studying the Galactic Centre magnetic field under the supervision of Dr Raymond Protheroe, Associate Professor of Physics at the University of Adelaide, and Dr Crocker, a former postdoctoral researcher at the University.

"The Milky Way just glows in radio waves and in gamma-rays produced by collisions of energetic particles, and is brightest near its centre. Knowing the magnetic field there helps us understand the source of the radio and gamma-rays better," says Dr Protheroe.

The Australian Research Council provided funding for the project.
Is it my imagination or is Australia starting to dominate science?

8 comments:

Jeffery Keown said...

Have a look at the orbits of the stars at the center of our galaxy. They are orbiting something we can't see, and they are orbiting it very fast.

Doing the math, one can calculate the mass that they are orbiting. It weighs more than 2 million solar masses.

Now... figure out the escape velocity of this unseen object. It is higher than the speed of light.

So... no matter what else is discovered... there is a black hole there. Like it or not.

However, since Oils routinely denies empiricism... he'll have a thought experiment and a ream of quotes ready to combat this notion. My prediction is that he'll bring up the paper about a lack of gravitational lensing at our galaxy's core, and claim this single example denies all of the other gravititational lensing data we have so far collected.

KV said...

OIM,

A moving charge is required for a magnetic field, no moving charge no magnetic field. A very strong magnetic field requires a very trong quantity of moving charges at very high speed... That leads to what JK wrote...

Quantum_Flux said...

There does not need to be a moving charge for a magnetic field to exist, a photon for example, contains an oscillating EM field and yet a photon has no charge.

Nobody has ever observed a black hole up close, so how could one distinguish a black hole from a bunch of dark matter or a ring of superatoms?

Unknown said...

"There is a giant magnet at the center of the Milky Way. It is the "black hole" in the logic, or rather lack thereof, of gravitation."

So... because there is a magnet, that is what is holding everything in orbit around the center of the galaxy, rather than gravity.

That's what you're saying? I don't want to get the wrong idea, here.

Thing is, you seem to be very adamant in misinterpreting pretty much all of science.

Do magnets, such as the possible ones sticking to your refrigerator even as you read this, have mass?

If you believe in mass, then mass is what gravity is influenced by. Two objects will attract each other, and the more massive they are, the larger the attraction. This also holds for three objects, as well as five, seventeen, and most other numbers of objects.

So just because something has a magnetic field, like the sun, that is what you think holds the earth in orbit around it (you do believe the earth orbits the sun, right?) and not gravity due to the mass of these objects.

I'd like to see any single person with a doctorate say anything to that effect.

Show me a link where anyone argues for anything similar to what you seem to (want to) believe.

Go ahead. Disprove gravity. Write out the equations. Explain how gravity lensing is actually just light in magnetic fields.

Sure, there's magnetism everywhere. We see radiation from certain bandwidths of the electromagnetic spectrum.

But we're kept in orbit, and on this planet, because we, and it, and everything, has mass.

Also, here's a neat article about magnetism.

http://blogs.discovermagazine.com/badastronomy/2008/08/20/the-magnetic-tendrils-of-ngc-1275/

The guy that wrote it is a scientist named Phil, and he writes

"Magnetism is a very important topic in astrophysics (despite some pseudoscientists lying and saying this force is ignored), but it’s not well-understood. It’s fiendishly complex, so much so that it’s a joke in astronomy: when giving a colloquium about an astronomical object’s weird features, saying it’s due to magnetism will always get a chuckle out of an audience. And it’s a standard joke that if you want to derail a talk, ask the speaker about the effects of magnetism. In three dimensions, magnetism is ferociously difficult to model.

But these fantastic images of tendrils show that magnetism is still a major player in galactic dynamics, and if we want to understand the effects of this long-reaching force, we may need to get comfortable in its loving arms. Or tentacles."

Actually, you've probably read this before, since you almost quote him on your blog page.

Except you quote him incorrectly, saying

“Magnetism is … a joke in astronomy….” — Phil Plait, writer, August 2008

You should probably fix that, before you get accused of taking his words out of context to try and suit your own agenda.

Jeffery Keown said...

You should probably fix that, before you get accused of taking his words out of context to try and suit your own agenda.

Too late. I accuse him of lying and quote mining every chance I get.

He should come with a label or something... Like a Mr Yuk sticker, but for science.

KV said...

QF,

In physics, a photon is an elementary particle, the quantum of the electromagnetic field and the basic "unit" of light and all other forms of electromagnetic radiation.

It is also the force carrier for the electromagnetic force. The effects of this force are easily observable at both the microscopic and macroscopic level, because the photon has no rest mass; this allows for interactions at long distances. Like all elementary particles, photons are governed by quantum mechanics and will exhibit wave-particle duality – they exhibit properties of both waves and particles. For example, a single photon may be refracted by a lens or exhibit wave interference, but also act as a particle giving a definite result when quantitative mass is measured.
(from Wiki, search photon).


There was no knowledge of photon when Maxwell developed his theories...

The key in understanding the photon is the concept of carrier of the electromagnetic force Which becomes easier by understanding the "spin" in quantum states...

When a charge is "spinning" it is moving on its axis of spin with zero translation.

Quantum_Flux said...

Hey, if you understand it like that KV....I think that Maxwell's equations having to do with time rates of change of the magnetic fields don't really apply to light speed objects and thereby you can have E-field polarizations in the shape of the chromosphere or electron orbital from which it came from, it is perhaps only when it interacts with a new charge (index of refraction) that the magnetic field begins oscillating.

Fungus the Photo! said...

Was Kepler finding this out for himself or was he alerted to it by someone else?

The obsession by the herd with defending gravity is fascinating! Do you all think it will disappear if you do not do so?

What is, is!