
Telescope Sees Star Dance Around Supermassive Black Hole, Proves Einstein Right - lelf
https://www.eso.org/public/news/eso2006/
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m12k
_Once again fails to falsify Einstein 's prediction_ This notion that anything
is ever fully proven needs to stop being spread around. Maybe pedantic, but
the anti-science crowd latches on to things like this - e.g. 'Science is
claiming to have all the right answers just as much as religion!' No it
doesn't, it has a long, long list of wrong answers, and a short list of
answers that haven't yet been proven wrong, which makes up our current best
approximation of 'the truth'. Einstein's theory just withstood another attack,
so it gets to keep its crown for now.

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doublesCs
No, you're mistaken. A _prediction_ was made and matches experiment, therefore
the _prediction_ was proven correct.

I believe you're repeating the idea that "_theories_ aren't proven correct,
you can only ever fail to falsify them", which is true. But you're applying
the idea to predictions, which makes it false because predictions absolutely
can be proven correct. In my opinion you come across as confused about these
ideas.

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m12k
You are correct, my comment should have read 'theory' rather than prediction.
Alas it is too late for me to edit it, so it will be forever wrong.

~~~
brlewis
Fortunately, HN has a list of your other comments, many of which have yet to
be proven wrong.

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willyg123
This video of stars orbiting Sagittarius A* taken over 20 years never ceases
to blow my mind. [https://youtu.be/DRCD-zx5QFA](https://youtu.be/DRCD-zx5QFA)

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fjfaase
Actually, the effect described here (if I am not mistaken), was already
observed in the orbit of Mercury before the theory of Einstein explained it.
See:
[https://en.wikipedia.org/wiki/Tests_of_general_relativity#Pe...](https://en.wikipedia.org/wiki/Tests_of_general_relativity#Perihelion_precession_of_Mercury)

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imvetri
Good point. Orbit is an orbit. "Don't just draw a full cycle of orbits to
highlight it is some amazing finding"

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evanb
Because the gravity is stronger in these cases it's possible that effects not
captured by Einstein's theory could be seen, just as Mercury probed stronger
fields, falsifying Newton's theory. But Einstein's theory survived this
scrutiny.

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kevin_thibedeau
In case anyone hasn't seen it here is the time lapse of stars orbiting
Sagittarius A:

[https://www.youtube.com/watch?v=TF8THY5spmo](https://www.youtube.com/watch?v=TF8THY5spmo)

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sq_
From the article:

> One hundred years later we have now detected the same effect in the motion
> of a star orbiting the compact radio source Sagittarius A* at the centre of
> the Milky Way. This observational breakthrough strengthens the evidence that
> Sagittarius A* must be a supermassive black hole of 4 million times the mass
> of the Sun

I love that scientists are so careful about stating that something is absolute
fact when they can't be 100% sure. The public's idea of things is definitely
that Sagittarius A* is a supermassive black hole, but that compact radio
source _could_ be something else, so they're careful to note that.

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jonnypotty
Such an amazing experiment, it's incredible that we can measure such things at
these distances with this level of accuracy. A shame we're more interested in
our own opinions than the science.

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akkartik
Anybody know what the precession period is for Mercury and this star? How long
does it take for the orbit to return to some starting orientation?

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akkartik
3 million years for Mercury, by my calculations and
[https://en.wikipedia.org/wiki/Apsidal_precession#Calculation](https://en.wikipedia.org/wiki/Apsidal_precession#Calculation)

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vagab0nd
How does one with good math/physics background gain a deeper understanding of
black holes? I'm fascinated by them and want to systematically learn the
theory behind it.

My plan is to start with General Relativity and Einstein's equations, maybe
some journal articles about black holes. Do you have any suggestions?

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abdullahkhalids
Watch some course lectures on Youtube. Work your way through some books such
as by Schutz or Sean Carroll, or if you are brave by Misner, Thorn and
Wheeler.

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greglindahl
I walked past a guy standing outside the Palo Alto Creamery, and he was
reading from a copy of Misner, Thorne, and Wheeler -- it's a very distinctive
looking book. Turns out he was a guy with a non-math background who had taught
himself enough to follow the book. I was impressed!

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JJMcJ
That book is big enough to visibly distort space-time on its own.

I'm impressed that the reader learned the math on his own. And, uh, what's my
excuse?

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ck2
Probably easier to list number of times Einstein was wrong (it's not even a
half dozen).

I hope I live long enough to see then use the moon for lensing or put
radio/telescopes on the far side.

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GuB-42
Ironically, one of these times is when he doubted the existence of black
holes. Yes, it means the article could have been subtitled "proves Einstein
wrong".

To be clear, while general relativity predicted the existence of black holes,
Einstein initially thought that they wouldn't be able to form in reality. [1]

[1]
[https://www.jstor.org/stable/1968902](https://www.jstor.org/stable/1968902)

