Gravitational Fields & Anti-Gravity Propulsion

[Vmedvil]

9 minutes ago, Unified Field said:

As for importance density and mass in the source of gravitational fields...

https://www.quora.com/Is-gravity-dependent-on-mass-or-on-density-How

So, we have some 4 options too choose:

a) only mass matters

b) density matters just a bit

c) both don't matter

d) both equally matter

I don't know, how abbout you, but I choose option d) ... But I'm not a real scientist, so let's ask NASA...

https://earthobservatory.nasa.gov/Features/GRACE/page2.php

And as always: Never A Straight Answer... But from those couple sentences, I can conclude, that according to them, density actually matters a lot... Exactly as I stated earlier...

But let me ask you just some questions: 

- Milky Way is an object around 100 Billion solar masses - so why it didn't become a one giant black hole 

- How strong is gravitational field of Milky Way, compared to a medium-size black hole?

- If attraction between Andromeda and Milky Way is caused by their gravitational fields - why those fields won't squeeze all their star o, into a single super-duper massive black hole?

- why galaxies are being attracted to eachother, as whole objects, instead to attract only particular star systems...?

Okay, Now I can answer all of these 

d) both equally matter

Angular Velocity of Stars around the SMBH

The minimum mass for a BH is 3 Solar masses, it is so much greater it is insane being 100 Billion solar masses

Same reason as why it didn't become a large BH

The Energy-mass of a SMBH is so much greater that individual stars being 4.1 Million Solar masses our galaxy's SMBH, Sgr A.

 

 

Edited December 26, 2017 by Vmedvil

[Strange]

1 hour ago, Unified Field said:

Anti-gravity doesn't generate any kind of force, directed towards the surface - it's just a vector directed in opposition to gravity.

That is why there is no such thing.

24 minutes ago, Unified Field said:

So, we have some 4 options too choose:

a) only mass matters

b) density matters just a bit

c) both don't matter

d) both equally matter

I don't know, how abbout you, but I choose option d)

Bzzt. Sorry, wrong answer. Please try again.

24 minutes ago, Unified Field said:

- Milky Way is an object at around 100 Billion solar masses - so why it didn't become a one giant black hole

Because it is larger than the Schwarzschild radius for that mass. And that is because everything is orbiting the centre of the galaxy. 

25 minutes ago, Unified Field said:

- How strong is gravitational field of Milky Way, compared to a medium-size black hole?

There isn't enough information to answer this. What is the mass of the black hole? How far away are you measuring the gravity?

26 minutes ago, Unified Field said:

- If attraction between Andromeda and Milky Way is caused by their gravitational fields - why those fields won't squeeze all their stars, into a single super-duper massive black hole?

Look up "ORBIT" in an introductory physics text.

 

[Vmedvil]

14 minutes ago, Strange said:

That is why there is no such thing.

Bzzt. Sorry, wrong answer. Please try again.

Because it is larger than the Schwarzschild radius for that mass. And that is because everything is orbiting the centre of the galaxy. 

There isn't enough information to answer this. What is the mass of the black hole? How far away are you measuring the gravity?

Look up "ORBIT" in an introductory physics text.

 

Ya, I disagree with d) being wrong because of the infinite density of BH, but I guess b) would be better.

[Strange]

Density is only indirectly relevant because (Newtonian) gravity depends on mass and distance. And in GR it may be indirectly related to pressure. But density itself doesn't appear in either theory.

[swansont]

2 hours ago, Unified Field said:

As for importance of density and mass in the source of gravitational fields...

https://www.quora.com/Is-gravity-dependent-on-mass-or-on-density-How

So, we have some 4 options too choose:

a) only mass matters

b) density matters just a bit

c) both don't matter

d) both equally matter

I don't know, how abbout you, but I choose option d) ... But I'm not a real scientist, so let's ask NASA...

https://earthobservatory.nasa.gov/Features/GRACE/page2.php

And as always: Never A Straight Answer... But from those couple sentences, I can conclude, that according to them, density actually matters a lot... Exactly as I stated earlier...

You could just look at Newton's gravitation law, and see that it depends on mass, and how far you are from the other mass. 

[Unified Field]

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Okay, Now I can answer all of these 

d) both equally matter

So at last we can agree in one point... But I would say, that it's the MASS and SIZE, which equally matter - density is combination of both.

I don't want to scare you, but this already makes us pseudo-scientists, as according to current knowledge, size of the source affects the gravity only by changing the distance from the center of mass (towards which the magnitude of gravity is growing)

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The minimum mass for a BH is 3 Solar masses, it is so much greater it is insane being 100 Billion solar masses

But what, if there's a nebula with a total mass of 10 Suns? Will it turn into BH? Because, according to the current knowledge, BH is created when critical mass of a body is reached - and there's nothing about the density...
http://abyss.uoregon.edu/~js/ast122/lectures/lec21.html

Official science tells, that all objects with mass create g. fields, in which magnitude of gravity depends only on the mass of source. According to current knowledge 2 spherical objects with 1kg of mass will create equally strong gravity - no matter, if one object is made of steel and the second is made of styro-foam...

Does it looks correct for you? For me doesn't...

I would say, that 1kg steel ball should create stronger gravity, than the styro-foam ball. Of course GR Theory doesn't say anything about it, so it will be probably considered as a heresy - but I would like to hear your opinion...

 

To be continued...

 

 

Edited December 26, 2017 by Unified Field

[Endy0816]

This is what the equation looks like for minimum density.

(c^2) / 2G = M/r

In your link they do mention the Schwarzchild radius.

Edited December 26, 2017 by Endy0816

[swansont]

2 hours ago, Unified Field said:

So at last we can agree in one point... But I would say, that it's the MASS and SIZE, which equally matter - density is combination of both.

But it's not. It's just the mass inside of the separation, r.

F = GMm/r^2

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I would say, that 1kg steel ball should create stronger gravity, than the styro-foam ball. Of course GR Theory doesn't say anything about it, so it will be probably considered as a heresy - but I would like to hear your opinion...

GR does. It's part of the equivalence principle. The kind of mass doesn't matter.

[Unified Field]

3 hours ago, Strange said:

That is why there is no such thing.

Tell it to the plasma inside microwave owen... It's iterior is separated from the atmosphere, so the force of buoyancy can appear only inside the owen - however there's almost no difference of medium density within such small place. So, if we won't assume, that the plasma has some magical way of knowing, what is the desity of air outside the owen, upward motion can't be explain with buoyancy... And because there's no better way to call a force, which is opposing the gravity, as anti-gravity, I will keep calling it this way, until you won't figure out a better name...

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Bzzt. Sorry, wrong answer. Please try again.

According to who? You? And who are you? Somehow I prefere to put bigger trust in a source, which has a "nasa.gov" in the adress...

It's great, that you decided to enlighten us with your knowledge. However maybe you should consider also to elaborate - just a tiny bit...

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Because it is larger than the Schwarzschild radius for that mass.

Exactly! And the mass, together with this radius, creates a property, which is commonly known as.... density (surprise!) 

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And that is because everything is orbiting the centre of the galaxy. 

So what? In solar System all bodies orbit around Sun and still sometimes a comet falls into the star. Why stars, which are rotating around the center of galaxy are not consumed by the central BH?

If the attraction between galaxies, would be created by the g. fields of central BH's, only the BH's would be attracted. Galaxies interact, as single objects and not an assemblies of fields - just as Solar System acts, as a single object, during interactions with other stars in the Milky Way.

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There isn't enough information to answer this. What is the mass of the black hole?

I don't know and I don't care too much

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How far away are you measuring the gravity?

As far, as it affects an object...

note: different objects will be affected by a g. field at different distances - depending on their masses (density?). But according to mainstream science it's probably a total heresy, as it is not described in GR....

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Look up "ORBIT" in an introductory physics text.

Actually it's rather hard to call the motion of Solar System within the Milky Way, as orbital...

 

42 minutes ago, swansont said:

But it's not. It's just the mass inside of the separation, r.

F = GMm/r^2

GR does. It's part of the equivalence principle. The kind of mass doesn't matter.

So does, or not? Because this:

F = GMm/r^2

doesn't explain, what is the difference of magnitude in g. fields for different densities of the source. 

And such correlation is something rather obvious - as objects with low density (gas clouds for example) create much weaker gravity, than celestial bodies with similar mass.

What are the different kinds of mass? I know only one kind of mass - the one, which has it's origin in subatomic  particles...

[swansont]

44 minutes ago, Unified Field said:

 

So does, or not? Because this:

F = GMm/r^2

doesn't explain, what is the difference of magnitude in g. fields for different densities of the source. 

Because only the mass matters. Not the density.

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And such correlation is something rather obvious - as objects with low density (gas clouds for example) create much weaker gravity, than celestial bodies with similar mass.

Not at the same distance.

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What are the different kinds of mass? I know only one kind of mass - the one, which has it's origin in subatomic  particles...

You brought it up, when you said two different objects of the same mass should have a different effect.

GR says no - mass is mass.

[John Cuthber]

41 minutes ago, Unified Field said:

however there's almost no difference of medium density within such small place.

The density of a gas at constant pressure is pretty close to inversely proportional to its temperature.

The plasma is hot enough to glow brightly.

So it clearly has a much lower density than the surrounding air.

So you are clearly talking nonsense.

[Unified Field]

2 minutes ago, John Cuthber said:

The density of a gas at constant pressure is pretty close to inversely proportional to its temperature.

The plasma is hot enough to glow brightly.

So it clearly has a much lower density than the surrounding air.

So you are clearly talking nonsense.

Yes - plasma has most likely smaller density, than air inside the microwave owen

That's why - plasma wants to move towards an area, where density of air is smaller

But - there's no such place within the owen (except the area, where plasma is located - but since plasma can't move to the inside of itself, you can simply ignore this fact)

So - plasma is deeply confused, as it doesn't even know about such reality, as "outside of owen", not to mention about something, like atmosphere or it's hypothetical density

 

So What happens with  plasma, if the owen would be placed on ISS?

a) it flows in random directions, looking for somekind of "outer space" (like someone during an attack of claustrophobia)

b) it flows freely inside the owen (like Tinker Bell fairy)

c) it places itself in the exact center of air mass, inside the owen (like a Shaolin monk)

d) explodes / implodes / teleports itself / annihilates time / collapses reality / create a black hole or wormhole / start to produce anti-matter / guess by yourself

e) makes something completely logical, but I still don't know, what might it be

 

Personally, I would choose the option b) but if I'm wrong, then correct me

[interested]

1 hour ago, Unified Field said:

And because there's no better way to call a force, which is opposing the gravity, as anti-gravity, I will keep calling it this way, until you won't figure out a better name...

Why say anti gravity, if you created a BH above you as you were falling towards the sun, you may fall towards the BH not the sun. This would not be antigravity. Alternatively if dark energy can accelerate galaxies apart, it could be maybe possibly be described as anti gravity. 

What is your Plasma made up from in your microwave, is it ionized hot air particles which are less dense than the surrounding air and would float. Or are you talking quarks and gluons, what is the make up of your plasma. I guess from the picture your plasma is giving off photons as electrons recombine with atoms. The focus of the microwave energy on the hot air in the microwave will more likely localize the ionization effect.

 

Edited December 26, 2017 by interested

[Unified Field]

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You brought it up, when you said two different objects of the same mass should have a different effect.

GR says no - mass is mass.

 

The same mass, but different density...

Please - I don't think, that it's THAT hard to understand the correlation between mass and density...

18 minutes ago, interested said:

Why say anti gravity, if you created a BH above you as you were falling towards the sun, you may fall towards the BH not the sun. This would not be antigravity. Alternatively if dark energy can accelerate galaxies apart, it could be maybe possibly be described as anti gravity. 

What is your Plasma made up from in your microwave, is it ionized hot air particles which are less dense than the surrounding air and would float. Or are you talking quarks and gluons, what is the make up of your plasma. I guess from the picture your plasma is giving off photons as electrons recombine with atoms.

 

Float in which direction? Without gravity there won't be no direction...

We can agree, that the force of such anti-gravity, is created by the buoyancy of plasma, inside the owen - as energetic particles want to move out from this medium, but gravity gives the direction of force (against). However, if this upward oriented force will become strong enough (what can be possibly done by adding more plasma into the owen, or by further increasing it's energy), it will most likely fly stright into space - no matter, if there will be some atmosphere around it, or not... So, is it actually an effect of buoyancy, if upward motion of owen won't be connected with the density of medium?

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Because only the mass matters. Not the density.

Then why nebulas create much weaker g. fields, than solid celestial bodies?

Why it's the interstellar gas, which is being attracted by planets and stars - even if the total mass of such gas cloud can be higher, than the mass of a solid body - and not the other way (planets attracted by gas clouds)?

Edited December 26, 2017 by Unified Field

[swansont]

44 minutes ago, Unified Field said:

The same mass, but different density...

Please - I don't think, that it's THAT hard to understand the correlation between mass and density...

Indeed. And since we see that mass, not density, appears in the equation, why do you still insist that density matters?

if the earth were to suddenly shrink, increasing the density of the earth, the orbit of the ISS (or any other satellite, including the moon) would not change.

[Unified Field]

4 minutes ago, swansont said:

if the earth were to suddenly shrink, increasing the density of the earth, the orbit of the ISS (or any other satellite, including the moon) would not change.

And if Earth would shring so much, that it would create a black hole - wouldn't it affect the orbits neither? 

Is the gravity of a black hole the same (or even weaker, due to the loss of plasma during supernova), as the gravity of the star, which was it's source?

Or is the gravity of black holes MUCH stronger, than gravity of stars?

But is a black hole created because of some mysterious increase of it's mass, or because of growing density of matter, which is being compressed by the gravity into something with the maximal possible level of density?

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Indeed. And since we see that mass, not density, appears in the equation, why do you still insist that density matters?

Because I use common logic, instead of some virtual equations...
And common logic tells, that by decreasing the size of Earth. we will increase the magnitude of it's g. field - and satellites will at some point, fall from the sky. Of course, we can disagree - as you prefer equations, instead of logic - so the only option, will be to actually shrink the planet and see, what will happen with the satellites...

[Strange]

4 hours ago, Unified Field said:

Does it looks correct for you? For me doesn't...

As it has been tested and used for hundreds of years and shown to be correct, it doesn't really matter whether it "looks" right to you or not.

2 hours ago, Unified Field said:

Tell it to the plasma inside microwave owen... It's iterior is separated from the atmosphere, so the force of buoyancy can appear only inside the owen

There is no plasma inside a microwave oven (unless things have gone very badly wrong). And buoyancy is not anti-gravity.

2 hours ago, Unified Field said:

According to who? You? And who are you? Somehow I prefere to put bigger trust in a source, which has a "nasa.gov" in the adress...

It doesn't say anything about density being relevant to gravity.

2 hours ago, Unified Field said:

Why stars, which are rotating around the center of galaxy are not consumed by the central BH?

Do you really not understand the concept of an orbit? I mean, really?

1 hour ago, Unified Field said:

The same mass, but different density...

Please - I don't think, that it's THAT hard to understand the correlation between mass and density...

It still makes no difference to the gravity.

Lets take an extreme example. If the sun (very low density) were to suddenly turn into a black hole (very high density) it would make no difference at all to the orbits of the planets. The gravity would be exactly the same. 

You can make all sorts of wild guesses and assertions, but as you have no theory and no evidence to support them, we can just ignore them in favour of the actual science. Which has been repeatedly tested and found to be correct.

1 hour ago, Unified Field said:

Then why nebulas create much weaker g. fields, than solid celestial bodies?

Because they are a very long way away. Sheesh.

 

6 minutes ago, Unified Field said:

And if Earth would shring so much, that it would create a black hole - wouldn't it affect the orbits neither? 

Correct. The orbits would be exactly the same. It depends on mass and distance only.

7 minutes ago, Unified Field said:

Is the gravity of a black hole the same (or even weaker, due to the loss of plasma during supernova), as the gravity of the star, which was it's source?

Yes. (Apart from the mass lost in the supernova.)

7 minutes ago, Unified Field said:

Or is the gravity of black holes MUCH stronger, than gravity of stars?

It is exactly the same as a star (or group of stars) with the same mass.

8 minutes ago, Unified Field said:

Because I use common logic, instead of some virtual equations...

Your "logic" (which appears to mean "common sense" and guesswork) gives the wrong answers. Science gives the right answers - we know this because the answers have been tested and are used, practically, every day.

 

9 minutes ago, Unified Field said:

And common logic tells, that by decreasing the size of Earth. we will increase the magnitude of it's g. field - and satellites will at some point, fall from the sky. Of course, we can disagree - as you prefer equations, instead of logic - so the only option, will be to actually shrink the planet and see, what will happen with the satellites...

And you "logic" is, sadly, wrong. Maybe you should learn a little schoolboy physics instead of relying on guesswork (calling it "logic" doesn't;t make it any more accurate).

[swansont]

20 minutes ago, Unified Field said:

And if Earth would shring so much, that it would create a black hole - wouldn't it affect the orbits neither? 

No change.

The strength of the field only depends on the mass.

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Is the gravity of a black hole the same (or even weaker, due to the loss of plasma during supernova), as the gravity of the star, which was it's source?

Weaker only because of mass loss. A star and BH of equal mass will exert the same gravitational pull at the same distance from the center.

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But is a black hole created because of some mysterious increase of it's mass, or because of growing density of matter, which is being compressed by the gravity into something with the maximal possible level of density?

It's because r has dropped, which means the force is stronger. 

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Because I use common logic, instead of some virtual equations...

Your logic is based on an incorrect premise, making your conclusions invalid.

 

[Unified Field]

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As it has been tested and used for hundreds of years and shown to be correct, it doesn't really matter whether it "looks" right to you or not.

Really? If density of an object doesn't matter for the gravitational fields, then why a black hole creates much stronger gravity, than the star, which became it's source (even if we assume, that there was no loss of material during the process)? Initially, mass of a black hole doesn't differ too much from the mass of the ex-star - and there are many stars with higher mass, than a black hole - and still they don't collapse...

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There is no plasma inside a microwave oven (unless things have gone very badly wrong). 

But there CAN be plasma in a microwave owen, if we will put open fire inside and turn it on...

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And buoyancy is not anti-gravity.

Yes! You're absolutely correct! Congratulations... Even if I was telling this, since the beginning of this thread (well, better later, than never)...

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It doesn't say anything about density being relevant to gravity.

https://earthobservatory.nasa.gov/Features/GRACE/page2.php

Yeah, it's quite easy to miss the right fragments in such a long text (actually, it isn't - but let's say it is...). So maybe I will copy and paste it here - just in case, if someone suffers to some extreme case of ADHD and can't focus for 3 minutes to read a single page or writing...

First one:

"We can think of gravity as the invisible force that pulls two masses together. When we speak of mass, we’re talking about the amount of matter in a substance. Density is a measure of how much mass is concentrated in a given space. Sir Isaac Newton discovered that as an object’s mass increases, the gravitational attraction of that object increases. For example, a container filled with a more dense material like granite rock has more mass and thus more gravitational attraction than that same container filled with water. The Earth’s Moon has considerably less mass than the Earth itself. Not only is the Moon smaller than the Earth, but it is only about 60 percent as dense as Earth. Thus, the gravitational attraction on the Moon is much less than it is here on Earth, and a person weighs less on the Moon. This weaker gravity is why we have the famous images of the Apollo astronauts taking “one giant leap for mankind” on the Moon’s surface."

Second one:

"This famous photograph of an astronaut taking a “giant leap for mankind” demonstrates the effect of the moon’s lower gravity on a person’s weight. Because the moon is smaller than the Earth and about 60 percent as dense, the astronaut’s weight is only about one-sixth of what it would be on Earth. Although they are not as dramatic as the Earth-moon difference, slight variations in the mass and density across the Earth’s surface do create differences in Earth’s gravity field."

Of course, they didn't say it directly, but it should be clear from those two fragments, that density of matter in a source has a GREAT importance for the force of gravity and properties of a g. field. Telling such heresies openly, is most likely strictly forbidden in the scientific society - as it threatens the dogma of Einstein's omniscience and absolute perfection of his GR Theory... But somene, who can read between the letters just a bit, should easily notice, that they mentioned about the density with some purpose...

to be continued...

[Strange]

1 minute ago, Unified Field said:

Really? If density of an object doesn't matter for the gravitational fields, then why a black hole creates much stronger gravity, than the star

It doesn't. 

However, because a black hole is smaller than a star with the same mass, you can get closer to it. And (as, of course, you know) gravity decreases as the square of the distance.

But, at the same distance, the gravity will be the same. 

So density des not change the gravity but a higher density means that you can get closer (or, to put it another way, the surface is nearer the centre). But density itself does not change the gravity. It is only the distance from the object and its mass that are important.

6 minutes ago, Unified Field said:

Of course, they didn't say it directly, but it should be clear from those two fragments, that density of matter in a source has a GREAT importance for the force of gravity and properties of a g. field.

Only if you don't understand what you read.

6 minutes ago, Unified Field said:

Telling such heresies openly, is most likely strictly forbidden in the scientific society - as it threatens the dogma of Einstein's omniscience and absolute perfection of his GR Theory...

Oh grow up.

[Unified Field]

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Do you really not understand the concept of an orbit? I mean, really?

I do not understand, why shouldn't we observe somekind of object, falling into the BH, if it's orbit will get close enough to the center? It happens sometimes in the case of planets or stars...

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It still makes no difference to the gravity.

Lets take an extreme example. If the sun (very low density) were to suddenly turn into a black hole (very high density) it would make no difference at all to the orbits of the planets. The gravity would be exactly the same. 

You can make all sorts of wild guesses and assertions, but as you have no theory and no evidence to support them, we can just ignore them in favour of the actual science. Which has been repeatedly tested and found to be correct.

If there's no difference between the gravity of a star and a black hole, which the star turned into - then why light can escape from all stars?

If you say, that it's because the radius of a black hole is smaller and there's closer distance to the center of mass - wouldn't it mean that light was trapped as well in the center of this star?

It's not a wild guess, but simple logic - gravity of black holes has to become stronger, in order to trap the light...

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It's because r has dropped, which means the force is stronger. 

Yes - you're almost there... Just one more tiny step:

What happens, when the size of an object is getting smaller, while it's mass remain the same? Need help?

And again right answer - as a result of this (very mysterious) process, strenght of gravity will grow indeed...

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Because they are a very long way away. Sheesh.

???

Long Time Ago

In a Galaxy Far, Far Away...

???

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It doesn't. 

However, because a black hole is smaller than a star with the same mass, you can get closer to it. And (as, of course, you know) gravity decreases as the square of the distance.

But, at the same distance, the gravity will be the same. 

So density des not change the gravity but a higher density means that you can get closer (or, to put it another way, the surface is nearer the centre). But density itself does not change the gravity. It is only the distance from the object and its mass that are important.

Oh, so light is being trapped in the core of a star, even before it turns into a black hole?

Interesting... Can you give me some sources of such impressive knowledge?

Edited December 26, 2017 by Unified Field

[Strange]

9 minutes ago, Unified Field said:

I do not understand, why shouldn't we observe somekind of object, falling into the BH, if it's orbit will get close enough to the center? It happens sometimes in the case of planets or stars...

I'm not sure what you are asking. We can observe objects orbiting a black hole (this provides some of the best evidence for the existence of black holes).

We cannot observe anything that falls into a black hole (passes through the event horizon) because no information can leave the black hole.

9 minutes ago, Unified Field said:

If you say, that it's because the radius of a black hole is smaller and there's closer distance to the center of mass - wouldn't it mean that light was trapped as well in the center of this star?

No, because only a small proportion of the mass of the start is within that radius so the gravity is not sufficient to stop light escaping. To create a black hole, the entire mass of the star needs to be within the Schwarzschild radius.

9 minutes ago, Unified Field said:

It's not a wild guess, but simple logic - gravity of black holes has to become stronger, in order to trap the light...

And, again, your "logic" is wrong.

9 minutes ago, Unified Field said:

Oh, so light is being trapped in the core of a star, even before it turned into a black hole?

No.

9 minutes ago, Unified Field said:

Interesting... Can you give me some sources of such impressive knowledge?

Which bit do you need a source for? But as you appear to know almost nothing, perhaps you could start here: https://en.wikipedia.org/wiki/Newton's_law_of_universal_gravitation

Feel free to ask questions about any bits you don't understand.

 

 

[Unified Field]

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Only if you don't understand what you read.

"Not only is the Moon smaller than the Earth, but it is only about 60 percent as dense as Earth. Thus, the gravitational attraction on the Moon is much less than it is here on Earth, and a person weighs less on the Moon."

"Because the moon is smaller than the Earth and about 60 percent as dense, the astronaut’s weight is only about one-sixth of what it would be on Earth."

 

Oh... So maybe help me to understand those sentences correctly - as I keep understanding them, as a direct explanation of density being a crucial property for the gravitational fields. I have to hallucinate...

[swansont]

27 minutes ago, Unified Field said:

Really? If density of an object doesn't matter for the gravitational fields, then why a black hole creates much stronger gravity, than the star, which became it's source (even if we assume, that there was no loss of material during the process)?

It doesn't.

27 minutes ago, Unified Field said:

 

  First one:

"We can think of gravity as the invisible force that pulls two masses together. When we speak of mass, we’re talking about the amount of matter in a substance. Density is a measure of how much mass is concentrated in a given space. Sir Isaac Newton discovered that as an object’s mass increases, the gravitational attraction of that object increases. For example, a container filled with a more dense material like granite rock has more mass and thus more gravitational attraction than that same container filled with water. The Earth’s Moon has considerably less mass than the Earth itself. Not only is the Moon smaller than the Earth, but it is only about 60 percent as dense as Earth. Thus, the gravitational attraction on the Moon is much less than it is here on Earth, and a person weighs less on the Moon. This weaker gravity is why we have the famous images of the Apollo astronauts taking “one giant leap for mankind” on the Moon’s surface."

Second one:

"This famous photograph of an astronaut taking a “giant leap for mankind” demonstrates the effect of the moon’s lower gravity on a person’s weight. Because the moon is smaller than the Earth and about 60 percent as dense, the astronaut’s weight is only about one-sixth of what it would be on Earth. Although they are not as dramatic as the Earth-moon difference, slight variations in the mass and density across the Earth’s surface do create differences in Earth’s gravity field."

Of course, they didn't say it directly, but it should be clear from those two fragments, that density of matter in a source has a GREAT importance for the force of gravity and properties of a g. field. Telling such heresies openly, is most likely strictly forbidden in the scientific society - as it threatens the dogma of Einstein's omniscience and absolute perfection of his GR Theory... But somene, who can read between the letters just a bit, should easily notice, that they mentioned about the density with some purpose...

to be continued...

What should be clear is that the density matters only in that it tells you what the mass is.

6 minutes ago, Unified Field said:

"Not only is the Moon smaller than the Earth, but it is only about 60 percent as dense as Earth. Thus, the gravitational attraction on the Moon is much less than it is here on Earth, and a person weighs less on the Moon."

"Because the moon is smaller than the Earth and about 60 percent as dense, the astronaut’s weight is only about one-sixth of what it would be on Earth."

 

Oh... So maybe help me to understand those sentences correctly - as I keep understanding them, as a direct explanation of density being a crucial property for the gravitational fields. I have to hallucinate...

Smaller and lower density means less mass. 

[Strange]

5 minutes ago, Unified Field said:

Oh... So maybe help me to understand those sentences correctly - as I keep understanding them, as a direct explanation of density being a crucial property for the gravitational fields. I have to hallucinate...

If you read the Wikipedia page on Newton's law of gravitation you will see that gravity is proportional to the mass of the planet and inversely proportional to the distance from the centre.

So, if two planets have the same mass but one of them is denser then that means the volume will be smaller and the surface will be nearer the centre (smaller radius). Therefore the surface gravity will be higher (just because you are closer the centre). It is the distance that is important. The higher density just allows you to get closer. It is not the density itself that changes anything.

So, if we consider a satellite in orbit above these two planets, the only thing that matters is how far the satellite is from the centre of the planet (and the mass of the planet). The density is not relevant because we are no longer considering the surface gravity.