Ruling on Einstein's BH's:

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Nice try....but really the proof of the pudding and all that?

Derailing? Nonsense, just showing hypocrisy for what it is.

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That's done everyday by others here more political savvy then I.

While flat Earth theory does have very limited applications and boundaries, GR of course is plainly opposite and quite encompassing, other than for the quantum/Planck limit.

And likewsie I care nought about your own opinions.
Again, for a professional, you are so unprofessional.

That's nice...See you at the Nobels....in your dreams

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Meaningless comment.

Self-reflecting then. I've commented on the pattern before. Very occasionally, you get your ears boxed for going too far too often, like happened here:
http://www.sciforums.com/threads/problem-of-gravitons-and-black-holes.157927/page-4#post-3410474
and later posts. There follows a phase where paddoboy acts passably civil and even objective. But it never lasts long. being contrary to paddoboy's ingrained nature. And it's showing again this thread.

 

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Think more about the proposition I think it would be impossible.
I base my conclusion upon my understanding of the limits of our imaging capabilities.

We can not get an image in the visable spectrum of a planet in a solar system in the closest of star systems and I think the challenge of capturing a disk or ring may be even greater.

Alex

 

Internet is a great resource but very few get to utilize it to any great effect. Instead of traveling miles and miles to the nearest uni library and spend dreary hours sifting through catalogues then journals etc. as in 'the good old days', now one CAN just type into a search-bar say 'event horizon telescope'. And, without moving from the chair, up pops hits like:
www.eventhorizontelescope.org [with various tabbed subcategory's - one with a nice, date ordered list of relevant technical articles]
http://www.bbc.com/news/science-environment-35258378
It is necessary to read the stuff though, and it helps to have a minimal background in physics and maths. A decent forum populated by competent folks does have the added advantage of, most times, acting as a 'crank filter' for those without critical reasoning skills.

 

Yes that's all I did and did not look at anything past wiki.
And all on a smart phone so dangerous in the hands of the masses.
Alex

 

Not really....Your claim/s re the two sensationalist threads, remain as wasted cyber space, and is there for all to see, if anyone takes the time to bother.

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Really once again your hypocrisy is astounding considering your own vitriol style: A pity I failed to report some of that nonsense instead of feeling sorry for you.

One can also think back to the extreme, episode of false indignation, angst and blow hard nonsense, you peppered the forum with when it had a three day breakdown.....

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Nice links. Thank you.

 

Searching and sifting does consume time, often too much, which then easily becomes an addiction downside.

Careful! There's a faint whiff of 'conspiracy theory' lurking there. You know - hintoid (my TM word) of a clever plot by TPTB to ironically dumb us all down via 'smart' phones. And we all know who will prick up the ears and launch into a tirade against 'conspiracy theories' at the slightest excuse, or often even without any excuse needed.

 

Well here the thing...I don't know.
I don't need to know I don't even want to know.
I have my thoughts about the various folk here but I don't care.

My judgement or say so does not highlight or confirm a fact.

Things just are and will remain so even without my personal qualification or judgement.

Finding facts on this forum can be demanding but I am prepared to sift thru all that goes on to pick out a few gems of knowledge.

Alex

 

Wiki was rather good I thought in particular their list of the various bodies or groups involved.

Wiki certainly has changed discussions at the pub.
Once folk would argue and rant, bully wave the finger, stamp around.

These days someone whispers into their phone holds it up to each in the group each nod and no fists thrown.

A backward step I say.

Alex

 

The simple fact Alex, as you recognised in your first post, the gist of the article in recognising and virtually imaging BH's or really their shadows, is certainly an example of the technology now available to cosmologists.
It works well with the aLIGO verification of gravitational waves and binary BH pairs. We have come a long way since the first Cygnus X-1 observation.

 

But he didn't. A sign you were rattled, but regardless of it being a blunder, you owe ForrestDean an apology.

Dredging really hard now. Vintage paddoboy. Go ahead, quote in context and in full what I actually wrote then if you wish to risk further Mod intervention. Fact is, I alone undertook the task of restoring quite a few entire threads that otherwise would have been radically mangled or entirely lost forever. With precious little thanks for doing so.

 

And of course aLIGO is due to come back on line again shortly after more upgrades.
Exciting times ahead!

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It is easy to be hard on journalists.

And they often get things wrong.

That can be annoying if you let it get to you but I see any news as just news.

If I want to know more I can whisper to my phone and it offers me everything in the world available on the subject.

Folk should not shoot the messenger either, in this case you, after all it is you that has taken the time to bring something back to the forum which you hope members will enjoy.

And good for you that you do.

I certainly do appreciate it.

As you know I don't like the squabbles that go on as I like to see everyone friends and happy together.

But I understand how things can go.
And I even got rattled at one stage such that I forgot my placid approach to conflict.

But I won't judge others because in truth so much of the time I am not even sure what folk are disagreeing about.

My astronomy forum is different, no fights there, I won't allow it even though I am not a moderator I seperate the parties before it gets ruff.

So my experience there is different to here.

My resolve here is to be respectful to everyone.

If some one is wrong it will stand out without my input.

I applause your efforts to bring in news and even though others have their issues with you I do wish they could appreciate your effort.

Alex

 

Thanks Alex.
While certainly journalists do tend to sensationalise, as do even forum members as I have pointed out, It's worth noting in this case the three who have raised objections, or see an excuse to cry foul, all have opposing or alternative agendas.

 

'Agendas'. Ah yes, I should have added 'agendas' to 'conspiracy theories' in #29. Well let's have it, shit stirrer. Since you have directly implied I have an 'agenda', you must know what it is. So exactly what is my nasty little 'agenda' that you are claiming to know? Vague BS won't cut it.

 

The following paper discusses aspects of the OP.......

https://arxiv.org/pdf/1410.3492v1.pdf

THE POWER OF IMAGING: CONSTRAINING THE PLASMA PROPERTIES OF GRMHD SIMULATIONS USING EHT OBSERVATIONS OF Sgr A∗


ABSTRACT
Recent advances in general relativistic magnetohydrodynamic simulations have expanded and improved our understanding of the dynamics of black-hole accretion disks. However, current simulations do not capture the thermodynamics of electrons in the low density accreting plasma. This poses a significant challenge in predicting accretion flow images and spectra from first principles. Because of this, simplified emission models have often been used, with widely different configurations (e.g., disk- versus jet-dominated emission), and were able to account for the observed spectral properties of accreting black-holes. Exploring the large parameter space introduced by such models, however, requires significant computational power that exceeds conventional computational facilities. In this paper, we use GRay, a fast GPU-based ray-tracing algorithm, on the GPU cluster El Gato, to compute images and spectra for a set of six general relativistic magnetohydrodynamic simulations with different magnetic field configurations and black-hole spins. We also employ two different parametric models for the plasma thermodynamics in each of the simulations. We show that, if only the spectral properties of Sgr A∗ are used, all twelve models tested here can fit the spectra equally well. However, when combined with the measurement of the image size of the emission using the Event Horizon Telescope, current observations rule out all models with strong funnel emission, because the funnels are typically very extended. Our study shows that images of accretion flows with horizon-scale resolution offer a powerful tool in understanding accretion flows around black-holes and their thermodynamic properties.


6. CONCLUSIONS:
In this paper, we analyzed the predicted spectra and images of various GRMHD simulations and plasma models for the accretion flow around Sgr A∗ , and narrowed the model parameter range by imposing the requirement that our predictions be consistent with the observed spectra and the 1.3 mm image size of Sgr A∗ . As seen in Figure 9, the best fit model spectra agree with observational data very well. The models are most variable at infrared wavelengths, which is also consistent with observations. It is important to emphasize here that, if the spectral properties of Sgr A∗ were considered without any image size constraints, the range of allowed model parameter would be significantly wider. This demonstrates the power of using images with horizon-scale resolution to distinguish between models that would otherwise make seemingly similar predictions. Future imaging observations from the completed EHT is expected to more easily distinguish disk-dominated from all funnel-dominated models. In Figure 11, we show the predicted 1.3 mm images for Sgr A∗ for the GRMHD simulations and plasma model parameters that are consistent with all current spectra and imaging observations. With the completed EHT, it will be straightforward to distinguish between the first two pairs of images from the remaining three pairs of images shown, i.e., the diskdominated from the funnel models, respectively. However, distinguishing among the various disk-dominated models and measuring the parameters of the black-hole and of the plasma, will require additional information from the EHT, including the polarization and scale dependent variability. We will explore these aspects of our models in future work.

 

Thank you Paddoboy for the recognition.
Of course the folk who have opposing or alternate agendas use opportunity as they see opportunity present that they feel will support their view.
That is a reasonable expectation.
So you should not be surprised.
If they seek to stir you up it is up to you how to manage that situation but you know it will come and I just think it is a pity threads get off track.

My concern is I do not like discord.
Does it affect the site?
I doubt it in fact there would be a case that may suggest the conflict generates traffic.
No doubt all players have folk out there who read what they say and probably hope their favorite poster will put so and so in his place.
I don't know and what I do know does not matter.
Anyways don't let anything upset you and keep up the good work.
Alex

 

and another......
https://arxiv.org/pdf/1303.5057v1.pdf


: A MASSIVELY PARALLEL GPU-BASED CODE FOR RAY TRACING IN RELATIVISTIC SPACETIMES:

ABSTRACT
We introduce GRay, a massively parallel integrator designed to trace the trajectories of billions of photons in a curved spacetime. This GPU-based integrator employs the stream processing paradigm, is implemented in CUDA C/C++, and runs on nVidia graphics cards. The peak performance of GRay using single precision floating-point arithmetic on a single GPU exceeds 300 GFLOP (or 1 nanosecond per photon per time step). For a realistic problem, where the peak performance cannot be reached, GRay is two orders of magnitude faster than existing CPU-based ray tracing codes. This performance enhancement allows more effective searches of large parameter spaces when comparing theoretical predictions of images, spectra, and lightcurves from the vicinities of compact objects to observations. GRay can also perform on-the-fly ray tracing within general relativistic magnetohydrodynamic algorithms that simulate accretion flows around compact objects. Making use of this algorithm, we calculate the properties of the shadows of Kerr black holes and the photon rings that surround them. We also provide accurate fitting formulae of their dependencies on black hole spin and observer inclination, which can be used to interpret upcoming observations of the black holes at the center of the Milky Way, as well as M87, with the Event Horizon Telescope.