Kevin's Watch

Wow sooo cool Nano .. bigger than our entire solar system? Wow

Why would that be impossible? You mean impossible for this particular telescope(s) to see a planet? Or impossible for a planet to orbit a black hole? I'm guessing the former, since the latter is possible.

However, the black hole at the center of M87 is truly gigantic. Its mass is about 7 billion times the mass of our sun. And its dimensions are huge as black holes go. It is a sphere with a radius about 130 times that of the Earth's orbit or about three times bigger than the average orbit of Pluto.

I agree that sounds like an unlikely place to find a planet orbitting.

wayfriend wrote:

However, the black hole at the center of M87 is truly gigantic. Its mass is about 7 billion times the mass of our sun. And its dimensions are huge as black holes go. It is a sphere with a radius about 130 times that of the Earth's orbit or about three times bigger than the average orbit of Pluto.

I agree that sounds like an unlikely place to find a planet orbitting.

Not really unlikely. A big fucker like that that hasn't had time to suck everything in YET, could have tons of planets. In fact, technically, being at the center of a galaxy, it has billions of STARS orbiting it, and most of them have planets.
HOWEVER:::whatever it is, can't be a planet. We simply could not see it if it was a planet.

But what I want to see [as I was saying to Ali elsewhere, and nano mentioned they're working on the image of] is OUR black hole Sag.A*. Wish the fuckers would hurry up.
[[ours is MUCH smaller---BUT it's so much closer the picture might be better, BUT it might not cuz there might be a lot more interfering stuff...if I recall the early storied about this correctly, looking at ours we're looking long-wise, THROUGH all the stuff in the plane of our galaxy [that's definitely so. we are] but M87 we're looking cross-wise, the thin direction ...so a lot less stuff in the way.

As long as you do not go beyond the event horizon, black holes are just like any other source of gravity. They have less mass than their original star, since they formed from a supernova ( at least at first, before they start attracting any other matter). And there was nothing preventing that star from having planets. The main difference is that they pack their mass into a much smaller space. But from a distance, gravity is gravity. As long as the planet is in a stable orbit, and not falling into the black hole, there would be nothing impossible about this (well, except maybe for the radiation, but that would not be a given for all black holes, just black holes near a gas cloud--and it's possible for the planet to be far enough away from that to be safe. Afterall: Mercury.).

Roll on Sag A then, I say especially if the pics are even more impressive.

Zarathustra wrote:Why would that be impossible? You mean impossible for this particular telescope(s) to see a planet? Or impossible for a planet to orbit a black hole? I'm guessing the former, since the latter is possible.

This planet is located far enough inside the gravity well that it should be falling into the black hole...and yet, it doesn't.

I'm a bit confused; I heard a scientist on TV when asked what exactly a black hole was, answer with a laugh. It's quite simple, he said, a black hole is an object of such huge mass that nothing, not even light, could escape from it's gravitational pull.

Does that mean that a black hole is a lump of matter, a dead star or the like. I thought a black hole was a singularity; a place where the gravitational force had become so intense that the matter had actually collapsed in upon itself to a point of infinite smallness, but infinite mass. A pinch-point where you could be drawn in and spun out to .......who knows where? That bit in films where they always show like a tube of swirling stretchy colours, not a regular workaday hunk of stuff, of bog standard matter? Tell me it isn't so!

ur-Nanothnir wrote: The photo of Sag A* was released, actually. The photo isn't as impressive though.

Do you have a public link to the image? I just keep finding M87 pics. I'm sad that it isn't as good---I had hopes due to closeness despite other problems...still I'd like to see it.

peter---thing you asked that nano didn't address:

No, it probably isn't "bog standard" matter under those conditions, even if it originates from the ordinary stuff.
I don't think anyone has a really good idea exactly what the stuff will act like.
Below a link on how fucking weird just your ordinary neutron star gets---or at least might get---...and black holes are a whole nother animal. [[that swirly/stretchy stuff in the films is pretty accurate---at least in some---BUT, it's not AT the "surface" yet, [in fact, since you can see it, it wouldn't even be past the event horizon yet...poetiphysics license.] in those...it's still falling in

https://www.quantamagazine.org/squishy- ... -20171030/

Hashi Lebwohl wrote:My attempts to remind everyone of the great Doctor Who episode "The Impossible Planet" have failed.

That is great...though, IIRC, it's a set of at least 2, maybe 3 episodes to get the whole story.
But where did you try to remind people? I didn't see it....


Anyway, I sorta/kinda agree on the difficulties of discussing it...but they aren't ONLY difficulties of discussion.
In the real things, the MATH breaks [and so do the "words" if you're trying to use normal language]...that's hard to discuss sometimes, but usually not. Math breaks all the time...so we switch to a different math.
Same with words.

In black holes it's not that. Yea, the words break, yea the math breaks but the problem is that the actual, physical WORLD breaks...at least for us so far. Cuz gravity overwhelms every other thing...and gravity is the thing that we know the LEAST about. In a way, we know nothing about it.

Agree, math and words break. It's not "just" a dense object. Anywhere that gravity is strong enough to suck light back into it is subject to relativistic forces like we cannot even yet comprehend.

If I get it I think we are saying that black holes can have different masses, the use of the term supermassive before the name would imply that some are not so. This being so, again if I get it, they are not then necessarily infinite in mass - though examples might exist that are so? Neither is it the case that the intense gravitational force has literally squeezed the matter down to a point of infinite smallness - literally to the point where the actual particles of the matter have ceased to occupy any amount of space that may be considered meaningful, that is, infinitely small. We are talking small to the point where even say a planc length is like a trip to the outer edge of the universe in comparison.

These two things, infinite mass - not infinite density mind you......or are they by necessity coexistent? - and infinite smallness constitute my understanding of what a singularity is? And black holes, not necessarily having them, are then not bound necessarily to be singularities? Corrector not?

Also I'm a little confused about the idea of the math 'breaking down' in the theory underpinning black holes. I'm comfortable with the idea of the words breaking down - the meaning of words is fuzzy at best - but math? Seems to me that if you are forced to swap to a different kind of math in order to get your understanding of a thing to hang together- then you are on shaky ground at best. A bit like that brain teaser where you send a I'd out to the shops with ten pennies, do a bit of inconsistent jiggling about from both ends and one of the pennies disapears, start changing horses mid race in a thing like this and it can only result in problems.........

No doubt the bods who do this stuff know what they are doing, by just saying is all.....

peter wrote: These two things, infinite mass - not infinite density mind you......or are they by necessity coexistent? - and infinite smallness constitute my understanding of what a singularity is?


Also I'm a little confused about the idea of the math 'breaking down' in the theory underpinning black holes.
if you are forced to swap to a different kind of math in order to get your understanding of a thing to hang together- then you are on shaky ground at best.

No doubt the bods who do this stuff know what they are doing, by just saying is all.....

Infinite mass and infinite density are not necessarily coexistent. Though infinite mass---IF unopposed by other forces/situations/realities---would eventually become infinite-density Uni-Hole.
IIRC, micro-black holes are possible with unbelievably small masses...I THINK you could make several micro ones from a single average eyelash. But the conditions to do so don't happen naturally very often. The common, natural ones start from masses a few times larger than our sun and on up. [[at least once I've seen the idea that very early on in the universe, LOTS of micro-holes could have been produced, and those micro-holes are what dark matter is.]]

Mass---of nearly ANY amount, no infinity required---contained in infinite [or at least "on its way to becoming infinite"] volume/smallness is what a singularity is, pretty much. [[almost any amount of mass, made DENSE enough, means the gravity sprints toward infinity...doing things that are mathematically incalculable and physically/geometrically impossible as everything is currently understood]]

But that isn't THAT hard to understand math breaking. [[the problem in general, I mean, not the problem with gravity/math/matter/black-holes...that's CRAZY hard...so hard no one's figured it out, they just know all the stuff we have breaks.]]

You can't draw an undistorted/unbroken map of the world on flat paper. You cannot wrap a ball in flat wrapping paper without ruining the paper...or the ball.

a-squared plus b-squared equals c-squared is TRUE on your map-paper, but it is FALSE on an actual globe. They require different math. Maths that contradict each other. [[but because we're smart we can code switch, and because of scale/size, many maths are often "close enough" even though, in real terms, they're always wrong.]]

The bods doing this DO know what they're doing...and they also know what they're doing isn't right/complete, so far. It's just way the hell righter than PREVIOUS stuff.
[[just like, contrary to the popular myth, most decent ancient seafarers knew damn well the world was round and they wouldn't fall off...they didn't know what WAS out there---hence discovery---but they knew it wasn't a fucking cliff to sail off]].

Bit of a tack change, I'm interested what this picture tells us about the scientific method?

I'm going to assume that this picture is just the same as the one of you or me on the beach on our holidays, only the light was way more difficult to collect, done iirc by loads of different telescopes pointed at the thing and then the final image being made up from the multitude of individual images obtained thereby. But the point being, this is a light generated image of a thing that exists. This is what it would actually look like to you or me as we approached it, assuming we could do so and live.

So we have a situation here where a thing that was born in the mind of a mathematician, that was predicted as a purely theoretical object (not like the planet Uranus, because we already knew what planets were, that they existed when Uranus was theoreticised) has been actualised by physical proof. I guess the Higgs boson would also qualify for this, but we can't actually see that so it remains somewhat theoretical, so sticking with the black hole, was the process of conception through to actualisation inductive, deductive, a combination of both?

This photo has to be a true milestone in our understanding of our understanding, if you get me, as well as a breakthrough in the actual area of the discipline in which it is concerned.

peter wrote: a true milestone in our understanding of our understanding, if you get me, as well as a breakthrough in the actual area of the discipline in which it is concerned.

Yea...a lot of words being written on that.

On other stuff:

I think the picture was mostly in radio frequencies, and so the color isn't true color, but yea on the rest. [[Though I'd bet if anyone has other spectrum pics, they could calculate and convert and create a true-color pic. It would probably look just the same, except blurry white with a blurry black center.]]

It came about by a mix roughly as you suggest...the basic story, if accurate, observation of how bodies move, thought experiment/imagination on that movement, conversion of that idea into mathematical and general form, then a guy [Schwarzchild, who doesn't get nearly enough props for all the stuff he did] supposedly while in the field working artillery, reframed and refined the math to exact solutions and eventually the idea of singularities/black holes, which Einstein really supposedly didn't believe in for a long time...but the math worked, and other predictions were confirmed by observations...rinse, repeat, take a picture of a supermassive black hole millions of light-years away.

As concise and coherent a synopsis as I've yet come across V! The pics were all over the UK media last week but thanks to your op I heard it here first! Nice work.

Vraith wrote:
a-squared plus b-squared equals c-squared is TRUE on your map-paper, but it is FALSE on an actual globe. They require different math. Maths that contradict each other. [[but because we're smart we can code switch, and because of scale/size, many maths are often "close enough" even though, in real terms, they're always wrong.]]

This is no joke--spherical geometry and spherical analytic geometry are more difficult and the usual rules do not normally apply.

Hashi Lebwohl wrote:

Vraith wrote:
a-squared plus b-squared equals c-squared is TRUE on your map-paper, but it is FALSE on an actual globe. They require different math. Maths that contradict each other. [[but because we're smart we can code switch, and because of scale/size, many maths are often "close enough" even though, in real terms, they're always wrong.]]

This is no joke--spherical geometry and spherical analytic geometry are more difficult and the usual rules do not normally apply.

Absolutely, no joke at all. and it's not just a couple, or a dozen, it's many many more maths than there are shapes of pasta...and every geometry based on a different shape of past requires different math.
[[Entirely different logics/maths are needed to describe the Flying Spaghetti Monster universe compared to the Flatulent Rotini-wieler verse, and the Linguini Lapidarial verse, etc. etc. etc.]]
Not to mention almost everything described by every system does not, and cannot, actually exist...we just accept the abstractions/definitions cuz it glues the other things together.