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Imaging a black hole - the EHT

Green Baron

By Green Baron
in Science & Spaceflight

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Green Baron

Green Baron

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Karl Schwarzschild

I can't bear it any more. Many have tried to pronounce it, especially in silly videos, few do it right and many even write it wrong (tz, sh or similar crippledness). For those like me who can't figure out how the international phonetic alphabet really sounds here a try on how to pronounce that name and the corresponding radius correctly:

The German "r" is spoken with an easy tongue instead of a broad retracted one, and the tongue's base is lifted up close to the soft palate. There is no rolling in it like in Italian or Spanish nor chewing gum like sounds or meowing like in American English. Maybe like the British English "barber", but a little more accentuated r, not just a prolonged ah.

 

Schwarz: sh like in shambles, v like Vladimir (Harkonnen, not Putin), a long "a" like the second one in banana, (not an "äi" like baby) the z is like a ts, spoken with some time. A "tz" exists in German as well ("Platz"), but this is shorter and harder. "Schwarz" is the colour "black".

-schild: this one is easier. Like the "shield" (that's what in means), but the i is shorter like the one in mill and the trailing d is pronounced between d and t, not as soft as in building and not as hard as in mattress.

And take your time, there is a short reconfiguration of the speech organ between the two words, even for a native speaker.

 

I want you all to practice that, exam next week.

:o:cool::D

 

Edited by Green Baron
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K^2

K^2

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8 hours ago, KG3 said:

But a magnetic field line that originates near a black hole doesn't lose strength do to general relativity?

There are definitely relativistic effects there, especially if the black hole rotates, which will affect strength and orientation of the fields. But it won't extinguish these fields entirely.

As for gravity, thinking of it as a field doesn't make much sense outside of classical physics. There are related fields in General Relativity, but none of them are "gravity" in the same sense we think of it in classical physics. For starters, most of these are tensor fields, not vector fields...

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Green Baron

Green Baron

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A proposed method to simplify the data and help finding relevant information:

Comment: https://aasnova.org/2018/09/24/planning-for-images-of-a-black-hole/

and the paper http://iopscience.iop.org/article/10.3847/1538-4357/aad37a/meta

I must say, it is over my poor head. But i like the closing paragraph in the comment: "soon". Whatever that means ...

:-)

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Green Baron

Green Baron

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Data evaluation from a 2013 observation campaign with a "smaller version" spanning about half the world:

http://iopscience.iop.org/article/10.3847/1538-4357/aabe2e

and:

https://www.mpifr-bonn.mpg.de/pressreleases/2018/7

tl, dr: Up to then, they were down to a resolution of about 3 Schwarzschild radii of the black hole in Sag A*. More can be expected from the "full size version".

Time to start gnawing fingernails ? :cool:

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Green Baron

Green Baron

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The EHT page has been updated by some pop science articles and presentations, as well as an outlook to future observations, when new telescopes in France and Greenland join (2020).

https://eventhorizontelescope.org/

Haven't watched yet, maybe tonight.

Took a break and watched the SXSW 2019 video. To me, there was some really good info in it.

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Green Baron

Green Baron

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An announcement for a presentation of first results:

https://eventhorizontelescope.org/blog/media-advisory-first-results-event-horizon-telescope-be-presented-april-10th

Starts at 13:00 UTC, links to channels that will stream the press conferences online:

https://www.youtube.com/watch?reload=9&v=Dr20f19czeE

east and:

https://www.youtube.com/c/VideosatNSF/live

west of the pond.

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Starstruck69

Starstruck69

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Thanks baron i missed that one:)

Not sure if the links below have already been posted but i will attach just in case. The map gives you an idea of the locations if you scroll down the link.

 

https://www.nature.com/news/how-to-hunt-for-a-black-hole-with-a-telescope-the-size-of-earth-1.21693?WT.mc_id=SFB_NNEWS_1508_RHBox

This could of course challenge Einsteins theory of relativity!!!

I will be watching this one intently:) :targetretro:

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YNM

YNM

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4 minutes ago, klesh said:

Slightly more oblong shadow than I would've imagined. Interesting.

It might be doppler shift...

But yeah. Might also have something to do with the rotation, or other things. Would be helpful to see more.

Edited by YNM
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