Binary Systems and Supermassive Black Holes

[antimatter]

In a binary system, when one star has a type Ia-II super novae the partner star in that system is still there, so would the black hole and star just continue to orbit?

What if the supernovae star surpasses a type II and becomes a supermassive black hole, will the other star

gets pulled in, but then what would happen to the black hole, would it just continue sort of spinning by itself,

but don't singularity's not spin?

Sorry if that's phrased sort of confusingly.

[Realitycheck]

I may be wrong, but I believe that a singularity is just a mathematical reference point to the central focal point of gravity.

[antimatter]

According to Wikipedia: "a point in spacetime in which gravitational forces cause matter to have an infinite density and zero volume".

[Realitycheck]

Which really gets into semantics, because there can be no such thing as infinite density and zero volume.

[Martin]

According to Wikipedia: "a point in spacetime in which gravitational forces cause matter to have an infinite density and zero volume".

 

Could you give the link, and the exact quote?

Wikipedia is not completely reliable, as I guess most of us know.

But what you quote here sounds more confused than usual. If they really say that perhaps we can get it corrected. context matters too.

 

In a binary system, when one star has a type Ia-II super novae the partner star in that system is still there, so would the black hole and star just continue to orbit?

What if the supernovae star surpasses a type II and becomes a supermassive black hole, will the other star

gets pulled in, but then what would happen to the black hole, would it just continue sort of spinning by itself,

but don't singularity's not spin?

Sorry if that's phrased sort of confusingly.

 

I agree with several of Agent's comments here.

 

Also there is some additional confusion. A type IA supernova does NOT FORM A BLACK HOLE. No supernova of any type forms a SUPERMASSIVE black hole. Of course an UNsuper ordinary stellar mass black hole can and does pull stuff in too, on occasion.

 

A type II supernova can occur regardless of whether the star is in a binary system or not. It might result in a black hole or a neutron star. If there was a binary partner before the explosion, the partner would not necessarily end up being pulled in, but it might. If there were a partner and if it were pulled in, then it would certainly contribute to the spin of the black hole.

 

Do you have a problem with this? I don't understand the problem.

Singularities are not assumed to exist in nature, they are places where theory breaks down. A singularity need not be an isolated point. A theory can break down along a ring or on a donut shaped surface or on an infinite region. So there are singularities (in theories) of different shapes and sizes. I don't mean that exist in nature, I mean existing in the classical theory of gen. rel. Quantizing gen. rel. tends to get rid of the singularities in those cases where it has so far succeeded (that is work in progress.)

 

A black hole can have spin. My advice would be since singularities don't exist in nature, don't worry about them. Improved theories get rid of them.

[antimatter]

Could you give the link, and the exact quote?

Wikipedia is not completely reliable, as I guess most of us know.

But what you quote here sounds more confused than usual. If they really say that perhaps we can get it corrected. context matters too.

 

http://en.wikipedia.org/wiki/Singularity

[Martin]

antimatter what you are giving a link to is not a Wikipedia article,

but a disambiguation page

 

It gives some twenty different pointers to twenty or so different articles about different meanings assigned to the word.

 

I agree that the phrase they have for "gravitational singularity" is misleading. One could say it is garbage. But that is just a few words completely out of context, so no matter how misleading they're hard to take seriously.

 

You can't just stop with a brief phrase on a disambiguation page! If you want to see what they really say you have to click on the article itself!

 

The article, which you haven't quoted yet, is what really needs correction, I think. Have a look at it and see what you think.

[antimatter]

antimatter what you are giving a link to is not a Wikipedia article,

but a disambiguation page

 

It gives some twenty different pointers to twenty or so different articles about different kinds of singularities.

 

I agree that the words they have for "gravitational singularity" are misleading. One could say they are garbage. But they are just a few words completely out of context, so no matter how misleading they're hard to take seriously.

 

You can't just stop with what it says in a half dozen words on a disambiguation page! If you want to see what they really say you have to click on the article itself!

 

The article, which you haven't quoted yet, is what really needs correction, I think. Have a look at it and see what you think.

 

...I actually did read it, I just sort of thought that what I quoted would sum it up better than anyway I could...

[Martin]

It is good you read the article.

(Although like many Wikipedia physics articles it contains misleading stuff, the amateur volunteer authors don't always reflect a balanced mainstream view. It is good to actually read Wiki articles, even though you don't believe them. Read the fine print, so to speak, don't just come away with a vague impression.)

 

So does anything in the article lead you to believe that singularities exist in nature?

 

If so, please quote it. We need some explicit words from the article itself that are experienced as misleading.

 

Maybe we can generate a complaint about it and get the article corrected!

[antimatter]

It didn't say within the article, I just assumed.

Why do we speak of them though, if they don't exist in nature, because wouldn't that mean that they don't exist at all?

[Klaynos]

It didn't say within the article, I just assumed.

Why do we speak of them though, if they don't exist in nature, because wouldn't that mean that they don't exist at all?

 

We talk about them because they appear in the maths, we don't like them because they arn't real :|

[antimatter]

What do you mean they appear in maths?

I don't understand, would you mind giving some examples?

[Klaynos]

The easiest one I can think of is:

 

[math] \Delta t' = \gamma \ \Delta t = \frac{\Delta t}{\sqrt{1-v^2/c^2}} \,[/math]

 

If you set v = c.

[antimatter]

uh...

if you have the time, or the patience, would you mind explaining that one to me?

I'm still...not really there in math in school...

 

does the triangle mean change?

[Klaynos]

yes, difference, but the important it is you get a division by 0 :'(

[antimatter]

By the way,

what exactly IS this equation?

 

And isn't division by zero just a 'forbidden' mathematical expression, rather than proving a singularity?

I'm a little confused...again

[Klaynos]

It's the special relativity time dilation equation.

 

It's not forbidden it's undefined I believe. And can be described as a singularity, 0's and infinities, neither are nice...