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Topic Title: 3D Magnetic field rotation of light
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Created On: 10 February 2014 09:02 AM
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 18 March 2014 10:15 AM
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jarathoon

Posts: 1042
Joined: 05 September 2004

The latest cosmological discovery at the south pole by the Bicep2 collaboration has been in the news over the last few days impacts on this discussion..."Detection of B-mode Polarization at Degree Angular Scales" - i.e. the spectacular new structure identified in regards to the rotation of the polarization angle of cosmic microwave background radiation.

Primordial gravitational wave discovery heralds 'whole new era' in physics

BICEP2: Primordial Gravitational Waves!

BICEP2 2014 Results Release

As this has been raised here, it would indeed be interesting to know more about the size and nature of the magnetic fields in the early universe that would needed to fully or partially account for the observed B-mode Polarization patterns (Faraday Effect) and perhaps any other potentially plausible explanations as well.

The Bicep2 team confidently ascribe the striking patterns in the B-mode Polarization to gravitational waves at a very early phase of a big bang inflationary expansion. I would like to know if there some physical reason for definitively ruling out magnetic fields affecting light polarization, much later on in the development of the universe?

If the BICEP2 teams measurement results holds up to later scrutiny they are definitely worthy of a Nobel Prize in their own right (independent of the theorical model to explain the results). Given the very speculative nature of cosmology my preference would be for the measurement team to be much more guarded in regards to theoretical interpretation at this stage, letting the theorists fight over the detailed interpretation as a separate exercise and in separate papers.

Without a little forced separation between theorists and experimentalists, the danger is that experimental researchers only end up seeing what they expect to see according to a single dominent theoretical paradigm, and discount measurement anomalies that don't quite fit their theory laden expectations.

My personal view is that the public pay more than enough money into the science to allow more than one scientific theoretical school of thought to co-exist simultaneously, especially so in a subject so speculative as cosmology. If strong churning convective mass flows and magnetic fields in the early universe cannot be ruled out as a possible theoretical explanation for these results then how can we really definitively know that the BICEP2 team have detected gravitational waves existing in their model of a very early inflationary universe?


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James Arathoon
 25 March 2014 03:45 PM
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acsinuk

Posts: 153
Joined: 30 June 2007

Hi James
Thank you so much for the links to BICEP2 sites. The guys at the South pole telescope are obviously very excited about the discovery that when looking to the very edge of the universe in the most unpopulated [clear] area that the MBR is not random and a balanced mix of B and E mode waves but rather highly polarized in one direction. To try and explain their finding to particle physicists they have unfortunately dreamed up gravitrons and dark matter which is totally misleading.
Why don't they just state that the universe appears to be magnetized and polarized in a common direction right from the time of the big bang. Then using Maxwells laws explain how that magnetization/polarization is responsible for pushing the stars apart and thus they could rightly claim to have solved the dark energy problem.
Their call for new 3D electromagnetic physics to explain these effects is of course totally justified.
CliveS
 25 March 2014 09:32 PM
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kengreen

Posts: 400
Joined: 15 April 2013

The most simple reply to all this is that modern physics is completely bonkers. They have yet to produce a believable hypothesis reference the Big Bang, Dark Matter, the lunatic assumption that the Universe has a boundary which is progressing (expanding) into an entity which does not/cannot exist - to name but a few of the red herrings! Hypothesis can only be converted to Theory when acceptable experiment offers confirmation? Is all very exciting fantasy.

Ken Green
 26 March 2014 08:38 AM
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ectophile

Posts: 546
Joined: 17 September 2001

Physics has been completely bonkers since the invention of relativity and quantum theory. But it works. It has delivered technologies that we now use in our every-day lives that shouldn't even be possible according to classical physics.

That's the thing about quantum theory in particular. Physicists can't even agree what it says about how the universe works, yet the equations deliver the correct answers.

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S P Barker BSc PhD MIET
 26 March 2014 03:46 PM
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jarathoon

Posts: 1042
Joined: 05 September 2004

ectophile is right; the computational frameworks that have been developed in physics, deliver the results that agree well with experiment and observation (when the handle is turned in just the right way of course). These are empirical and data driven methods that have great utility in very well defined domains; the sort of methods engineers are used to working with and in part helped to inspire.

Cosmology is difficult and speculative, firstly because observational evidence is limited to our single view of the sky, and secondly because creating a consensus overarching teaching framework, the so called "standard model of cosmology", needs multiple inconsistent and incomplete physical theories to be glued and stitched together in just the right way, using a range of new hypothetical fields and substances (dark energy, one or more inflation fields and dark matter).

The two main approaches to producing better physical theory are:

(a) using top-down approach to generalise lower level theories in a mathematical sense, even if these lower level theories are a range of logically inconsistent mathematical frameworks, designed specifically to work within more limited and differentiated domains (This approach often consists in adding more physical spatial dimensions or more universes in addition to the one we observe);

(b) using a more bottom-up and philosophical approach of examining existing and more historic qualitative assumptions and concepts (explicit and implicit) for clues in how to proceed.

Einstein used both these two approaches in his career, so they are not necessarily mutually exclusive paths to take. However examining existing and historic assumptions and concepts (explicit and implicit) is time consuming and difficult, and does not result in large volumes of papers at the "cutting edge of science". Given the pressure on professional academics to produce lots of papers each year, it is quite clear why most academics follow route (a) exclusively, even if it becomes illogical, unproductive and dysfunctional in the extreme (in the extreme producing vast numbers of theories and speculations that cannot be tested and differentiated using experiment or observation). Perhaps we should just admit that route (b) in physics is now more suited to a crowd of amateur scientists with a range of different biases and crazy ideas, rather than professional scientists that need to earn an income and peer support for their research efforts. However if this is admitted perhaps some professional mainstream effort should go into managing and nurture this free resource of amateurs.

My personal belief is that there is probably enough observational and experimental data available to do a better job in creating a smaller set of more consistent wider domain physical theories than my teachers could provide me with. The major area of science I got interested in, in my youth, where there was indeed a recent and significant revolution of ideas, concepts, outlooks, interpretations and measurement techniques, was in the field of geophysics and geology. This revolution started in the 1950's with the reappraisal of Alfred Wagener's Continental Drift Theory. I don't think this earth science revolution is fully completed yet and I still hope that the outwash from it may eventually help transform our current views of mainstream physics, chemistry and biology.


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James Arathoon
 26 March 2014 05:19 PM
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Zuiko

Posts: 521
Joined: 14 September 2010

Originally posted by: ectophile

Physics has been completely bonkers since the invention of relativity and quantum theory. But it works. It has delivered technologies that we now use in our every-day lives that shouldn't even be possible according to classical physics.


I'd disagree that special relativity is bonkers. It's common sense, the maths is simple enough for school children, being little more than the application of pythagoras's theorem.

General relativity may appear bonkers because it predicts how fast accelerating massive objects appear to behave in all frames of reference (a phenomena we do not encounter in our every day lives); and the maths is very difficult.

Quantum mechanics is only appears bonkers because it is statistical and the maths is beyond most engineers and many scientists, who resort to the help of mathematicians. But then so is Boltzmann's thermodynamics a statistical theory. And that is mind-bending. Even Einstein considered Boltzmann's papers difficult to understand.


The world is a stranger place than we imagine; we are evolved to understand and predict the behaviour of slow moving, medium sized objects such as animals on the African Savannah. That the rest of nature is not constrained to behave like our everyday experience should not be considered bonkers, it seems completely logical!

Edited: 26 March 2014 at 05:39 PM by Zuiko
IET » Energy » 3D Magnetic field rotation of light

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