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Gravitational Energy


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The mass of a star represents the degree of gravitational attraction, however what role does the spinning of the star upon it axis play? If it did not spin would it also be unable to hold objects in its orbit? And if the spinning of the star is essential to holding objects in its orbit, do those objects drain the star of ‘gravitational energy’ by slowing that spin down with their own contrary inertia?

 

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Is not its inertial mass angular momentum in itself?

 

Nope, inertial mass and angular momentum are completely different, you can have one without the other.

 

What is the cause of angular momentum in stars?

 

 

The origin is the fact the nebula was spinning, why this is I've not covered yet, ask me in a couple of months and I might be able to answer you ;)

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It seems to me that angular momentum had a key role to play in the breaking of symmetry, if not that of the forces - then at the very least - in the differing composition of the bodies of mass we observe.

 

As far as gravitational energy is concerned and the conservation of energy law, it surely must take energy to ‘hold’ a body together, and so the loss of energy that takes place when an object (whose inertia is contrary to the centre of attraction) is caught in the gravitational field of that attraction, is energy lost in the destabilising of the ‘holding together’ of that body.

 

 

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It seems to me that angular momentum had a key role to play in the breaking of symmetry, if not that of the forces - then at the very least - in the differing composition of the bodies of mass we observe.

 

Not quite sure what you mean with the second bit here, or really the first...angular momentum is important in star and planet formation because most nebula (or at least the ones I'm aware of) are spinning. But angular momentum is not a force.

 

As far as gravitational energy is concerned and the conservation of energy law, it surely must take energy to ‘hold’ a body together, and so the loss of energy that takes place when an object (whose inertia is contrary to the centre of attraction) is caught in the gravitational field of that attraction, is energy lost in the destabilising of the ‘holding together’ of that body.

 

It doesn't take energy to have something still in a gravitation potential. You gain energy by moving closer to the CoM and lose it by moving further away. As large masses are normally spherically symmetric (and at least cylindrically symmetric around their axis of rotation) then nothing is moving in the potential.

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Klaynos

 

Yes sorry, I realise my wording has kind of placed angular momentum as a phenomenon causing the forces, as a pose to been a product of them. So is there an equation that you could explain to me that clarifies how angular momentum results from an interaction of the differing forces.

 

It seems as though the symmetry breaking I mentioned is only applicable to bodies of mass. Allow me explain further…

 

Imagine a central point of attraction (for this exercise probably better that it is a spherical object such as a star) surrounded by a continuous ring of matter (like the rings of Saturn but without the gaps), now take a cross section of that matter, wherewith you are able to observe that the heavy elements are closer to the point of attraction, and the lighter been proportionally further and further away.

 

Now imagine the cross section as a line from the beginning of the ring to its outer limit, and without breaking that line apply angular momentum, so you have something that looks like the spiral arm of the galaxy. Would that ’string’ of matter not eventually ‘snap’ creating something that looks like an elliptical galaxy. Wherewith the differing compositions of the bodies in orbit have been ‘set’.

 

 

Gravitational Energy

 

Errmmm, not quite sure about your reply. Is gravity a form of energy?

 

 

It sounds silly what I have asked above: Is gravity a form of energy?

 

If gravity is a result of mass, e=mc squared states that gravity is a resulting energy of mass!?

 

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Imagine a central point of attraction (for this exercise probably better that it is a spherical object such as a star) surrounded by a continuous ring of matter (like the rings of Saturn but without the gaps), now take a cross section of that matter, wherewith you are able to observe that the heavy elements are closer to the point of attraction, and the lighter been proportionally further and further away.

 

This would occur if the particles could scatter off of each other and trade energy and momentum.

 

 

It sounds silly what I have asked above: Is gravity a form of energy?

 

If gravity is a result of mass, e=mc squared states that gravity is a resulting energy of mass!?

 

 

E=mc^2 doesn't say anything like that.

 

There is such a thing as gravitational potential energy. Gravity, however, is a force (or a curvature of space if you view it geometrically). but since [math]F = -\nabla U[/math], gravity isn't special in that regard.

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Before I start, I am viewing the electromagnetic wave as having no mass, because even if you were travelling along side it - to measure it - you would have to take a 90-degree turn, by which time it has speed away at the speed of light.

 

When electromagnetic waves are projected out from a star, the light has an inertia moving directly away from that star. However if light passes near enough to another star, its inertia – which I am viewing as a point of forward momentum - is in keeping with the bending of space-time around that star (ie as though it had mass).

 

As light is not able to increase in speed, once caught, it is only able to leave the warping, if the warping itself is confined to a two dimensional plane, such as observed in the accretion disks around black holes. And so the light that is warped by stars enters above or below the plane, and is warped as it moves closer to it and is de-warped as it moves away there from.

 

Right or Wrong?

 

 

If the Big Bang started from a central point, and the energy it released was in the form of electromagnetic radiation, how would that inertia (moving directly away from the ‘singularity’) - and with the above in mind, lacking in mass - be warped by space-time, other than if there was already another point beyond the first wave of radiation?

 

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I'm confused possibly from all the writing I've done over the last week (nearly 8000 words all about one topic!).

 

But I'm going to answer the one bit of the post I felt I understood. (Sorry who ever gets to the rest)

 

If the Big Bang started from a central point, and the energy it released was in the form of electromagnetic radiation, how would that inertia (moving directly away from the ‘singularity’) - and with the above in mind, lacking in mass - be warped by space-time, other than if there was already another point beyond the first wave of radiation?

 

The central point from which the big bang started is everywhere, everything in the universe is at that central point.

 

I think it's also important to note that photons are massless, and that they are 'caught' so they cannot escape only if they fall within the even horizon of a black hole, although I'm not sure this is important here.

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OK, I'll give this one more day before I take it to another forum...
I don't know whether that is a threat, or you being polite and informing us, or just a general way of bumping your thread... but regardless:

 

I don't know exactly what your current question is, seemingly your original post has been completely answered, so from your post #9 I see this question:

 

As light is not able to increase in speed, once caught, it is only able to leave the warping, if the warping itself is confined to a two dimensional plane, such as observed in the accretion disks around black holes. And so the light that is warped by stars enters above or below the plane, and is warped as it moves closer to it and is de-warped as it moves away there from.

 

Right or Wrong?

Wrong. I assume you know that gravity causes space-time to bend, it is important to appreciate that it is the very "fabric" of space-time that is bending.

 

Light, as we know, travels in straight lines. But what is a "straight" line in a bendy (non-Euclidian) 3D system? We can define "straight" as the shortest distance between two points.

 

Combining my previous 2 paragraphs: when light travels in a region of bent (due to gravity) space-time, it must follow the shortest path between any two points. This shortest path follows the bent contours of space-time. So light may seem to bend, but in reality it is merely following the contours of space-time, and thus travelling in a straight line, where "straight" is defined in the non-Euclidian space-time system.

 

I hope this answers your question. If you have anything else just ask, there are many people here who are qualified and knowledgeable enough to answer almost any answerable question you throw at us (this is not a challenge!).

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I hope this answers your question.

No, not in the slightest.

 

In fact it is so inadequate I do not even feel the need to defend my point. As you are so far up your own jacksy, nor do I wish to waste my time straitening your opinions.

 

I’m off elsewhere to find people with open minds.

 

 

 

 

 

 

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I hope this answers your question.

No, not in the slightest.

 

In fact it is so inadequate I do not even feel the need to defend my point. As you are so far up your own jacksy, nor do I wish to waste my time straitening your opinions.

 

I’m off elsewhere to find people with open minds.

Open minds? If open minds mean to agree with your points, than I give up from "open mindness"!
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No, not in the slightest.

 

In fact it is so inadequate I do not even feel the need to defend my point. As you are so far up your own jacksy, nor do I wish to waste my time straitening your opinions.

 

I’m off elsewhere to find people with open minds.

What!? You asked a right/wrong style question, which I then told you was wrong, and I then proceeded to explain why using well known and accepted physics. I don't see what your problem is and clearly you cba to explain your problem, so how can you ever expect to resolve it?

 

From your apparent attitude the only thing I can assume you mean by "open minds" is people who will just nod blindly at you and tell you that everything you says is right, even when it's clearly a load of bull.

 

Au reviour and good riddance to you.

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I don't see what your problem is and clearly you cba to explain your problem, so how can you ever expect to resolve it?
Sucked you in with the passive posts, didn't he? The aggressive post earned him an infraction. Thanks for not stooping to the same level. ;)
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How does the bent space-time around a star that the light in question enters into, unbend itself allowing light that has been bent by it to escape to an observer on earth?

 

Replying to comments made by people not even involved in this thread...

 

If you look at the - What makes mass? thread, I think you'll find that I was 'passive' until I realised that ‘your’ minds are so closed that, when I tried to discuss how there are laws governing human behaviour that are as free from crookedness as laws such as - Kepler’s law of planetary motion, ‘you’ dismissed this as irrelevant to the thread.

 

Is that just your own cultural opinion? And am I not entitled to put my own case across with regards to the fact that I believe - the same laws that govern the physical universe also govern the ’mind’? And if I am unable to discuss this in a forum entitled pseudoscience and speculation, where am I able to discuss this?

 

 

 

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You seem to misunderstand what is happening, the light is not trapped by the light. If you put a heavy weight down on your bed and roll a ball so that it should pass by it, if you roll the ball fast enough it will curve but still fall off the other side of the bed.

 

Although quite why I'm answering you with an attitude like that I dunno.

 

You still need to discus things in a scientific manor.

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Here's an image that I found that may help you:

 

slide5.gif

 

The dotted line would be the path of a body, passing by the another bigger body, it curvature due to gravity. IMHO the curve is a bit exagerated, but it gives the general picture.

 

As for why exactly the light follows the bend, well in this picture:

 

spacetime.jpg

 

imagine if you took a little ball bearing and rolled it along, so it passed close to the dent in the sheet. The ball would roll along, then would bend as it went near the indented part, then, assuming it's moving fast enough and the pull is not strong enough, it will escape on the other side and continue in a straight line, but at a different angle to the original path, because the indentation in the sheet caused it to curve.

 

The exact same things happen to a photon passing by any other object with mass, although it is only really noticable when the other mass is really big, like a planet or star. Although it's also important to note that this is more due to the fact that the photon must follow a "straight" (shortest distance between two points) path, and not because it falls into where space-time (the sheet) is bent.

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Replying to comments made by people not even involved in this thread...

 

, I think you'll find that I was 'passive' until I realised that ‘your’ minds are so closed that, when I tried to discuss how there are laws governing human behaviour that are as free from crookedness as laws such as - Kepler’s law of planetary motion, ‘you’ dismissed this as irrelevant to the thread.

 

 

Loose the Attitude, and you May fare well here, keep it UP, and you`ll be Very short lived.

how`s That for an Un-crooked Law?

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5614, I am lost as to why you have provided such a detailed account of the warping of space-time around a star/body (which I already understand), only then to say:

 

this is more due to the fact that the photon must follow a "straight" (shortest distance between two points) path, and not because it falls into where space-time (the sheet) is bent.

 

 

As far as I can attain, we are both of the understanding that electromagnetic radiation is unable to increase in speed, therefore for it to enter into a segment of warped space-time, that warping must be already greater than the straight-line inertia of the radiation (meaning that the electromagnetic radiation is unable to escape there from as it is unable to increase in speed, as a body of mass would when moving closer to the central point of warping in relation to Kepler‘s law of planetary motion).

 

To put this into a clearer context, the warping of space-time is ‘felt’ further out from the body if an object has less speed than light, which in itself will only be effected if the body is big enough, and if it passes close enough by. So the warping of space-time is relative to the inertia & speed of the phenomenon entering into that warped space-time - the greater the speed, the closer a body needs to be to be warped, but even if light is not warped the space-time it enters into may be warped for a body with less speed.

 

And hence your point of light not entering into where space-time is bent, rather the photon must follow a straight path/shortest distance scenario, which is in itself is flawed (or my understanding of it is).

 

It has been observed (has it not), that when the sun is blocking the direct line to a star, the light of the star (in question) has been observed, however because it should not be observable the star appears to be in a different place in the heavens than if it had been observed without the (lets call it) suns interference?

 

My closest current perception of the straight line phenomenon you speak of, is comparable to what happens with the solar wind when it is deflected by the earths electromagnetic field, it parts and then ‘re-joins’ after passing by the earth. In this scenario the light is deflected away from the earth before been brought back together.

 

I am unable to comprehend how light that is destined to be ’absorbed’ by the sun, which for arguments sake is in a direct line between the earth and the source, can reach the earth unless by the afore mentioned scenario. On the other hand I refer to light that is not destined to reach earth, but enters into warped space-time and so does reach earth, and shows the source in a different place in the heavens, a scenario your straight line hypothesis is unable to explain, as my understanding of it would dictate that the source would show up in the same place.

 

 

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As far as I can attain, we are both of the understanding that electromagnetic radiation is unable to increase in speed, therefore for it to enter into a segment of warped space-time, that warping must be already greater than the straight-line inertia of the radiation (meaning that the electromagnetic radiation is unable to escape there from as it is unable to increase in speed, as a body of mass would when moving closer to the central point of warping in relation to Kepler‘s law of planetary motion).

 

Urmmm photon inertia?

 

The photon can have it's course bent without being unable to escape, if you read my last post.

 

To put this into a clearer context, the warping of space-time is ‘felt’ further out from the body if an object has less speed than light, which in itself will only be effected if the body is big enough, and if it passes close enough by.

 

Gravity is "felt" an infinite distance away.

 

So the warping of space-time is relative to the inertia & speed of the phenomenon entering into that warped space-time - the greater the speed, the closer a body needs to be to be warped

 

Nope, but slower things will be warped more

 

, but even if light is not warped the space-time it enters into may be warped for a body with less speed.

 

This is how anything is warped, most cases one mass is so much larger than the other it's insignificant.

 

And hence your point of light not entering into where space-time is bent, rather the photon must follow a straight path/shortest distance scenario, which is in itself is flawed (or my understanding of it is).

 

Flawed how? The photon travels straight, and space curves.

 

It has been observed (has it not), that when the sun is blocking the direct line to a star, the light of the star (in question) has been observed, however because it should not be observable the star appears to be in a different place in the heavens than if it had been observed without the (lets call it the) suns interference?

 

Yep, solar lensing.

 

My closest current perception of the straight line phenomenon you speak of, is comparable to what happens with the solar wind when it is deflected by the earths electromagnetic field, it parts and then ‘re-joins’ after passing by the earth. In this scenario the light is deflected away from the earth before been brought back together.

 

Not really a good comparison.

 

I am unable to comprehend how light that is destined to be ’absorbed’ by the sun, which for arguments sake is in a direct line between the earth and the source, can reach the earth unless by the afore mentioned scenario.

 

The light was never going to be absorbed by the sun it was going to pass beside the sun but was bent slightly to hit the earth.

 

On the other hand I refer to light that is not destined to reach earth, but enters into warped space-time and so does reach earth, and shows the source in a different place in the heavens, a scenario your straight line hypothesis is unable to explain

 

It explains it fine, mathematically.

 

as my understanding of it would dictate that the source would show up in the same place.

 

If you work through the maths it doesn't.

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Klaynos has replied to most of your post, however I will add my own expansion on his response:

 

5614, I am lost as to why you have provided such a detailed account of the warping of space-time around a star/body (which I already understand), only then to say:

 

this is more due to the fact that the photon must follow a "straight" (shortest distance between two points) path, and not because it falls into where space-time (the sheet) is bent.

In the analogy the light would fall down in to the dent, because the analogy says that wherever there is a dent things will fall down in to it, as if there were some gravitational source beneath the rubber sheet. In reality there is no gravity source beneath space-time(!), the dent itself is the cause of the force. A photon has energy and is thus affected by this force. An alternative (and equally valid) explanation is that the photon must follow the shortest path, and the shortest path in a non-Euclidian system follows the "contours of curvature" in that system, i.e. a photon will follow a bent path, if space-time is bent.

 

And hence your point of light not entering into where space-time is bent, rather the photon must follow a straight path/shortest distance scenario, which is in itself is flawed (or my understanding of it is).
I think the definition of "straight" may be what is confusing you. See the end of my previous paragraph.

 

It has been observed (has it not), that when the sun is blocking the direct line to a star, the light of the star (in question) has been observed, however because it should not be observable the star appears to be in a different place in the heavens than if it had been observed without the (lets call it) suns interference?

....

I am unable to comprehend how light that is destined to be ’absorbed’ by the sun, which for arguments sake is in a direct line between the earth and the source, can reach the earth unless by the afore mentioned scenario

Light that is going directly towards the sun will get absorbed by it, of course, but light that is going to pass nearby to the sun will be affected (it's path bent) by the sun's gravitational field. This is known as Gravitational lensing, follow the link and look at the images, which show what is happening.

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