Thread: gravity

I watched a show on gravity (what is wrong with gravity) and it was kind of facinating. They showed LIGO a gravity wave experiment made in 2002. As a very small side comment they mentioned it had zero results.
I thought what a collosal waste of money (500-600 million). perhaps gravity isnt what they think it might be or maybe just the earth has too many problems for the detector to work correctly (traffic vibrations, earthquakes, moon tidal tugs etc)

anyhow, that got me thinking of gravity and I wonder if gravity on an object in space can be diminished by being on the reverse side of the planet. so here is the experiment (mainly wondering if this has ever been done).

put a satillite in space around the earth and see if the gravity pull of the sun is dimished by the blocking of the earth. I know you would have to calculate out of the numbers the diffence in distance from one side of the planet to the other in distance to the sun.

so if the gravity is the same then does gravity bend around the earth or perhaps goes directly through the earth without any measurable interferance.

actually I have no idea if the gravity we feel from the sun is even big enough to measure.

(experiment could probably be done on the surface of the earth also.

Lorddog

Hello lorddog,

do you remember where you have seen the show?

Steve

Lorddog,

All mass exhibits gravity, gravity is cumulative (using vector maths) in an eclipse the earth is still 'tugged' by the sun even though it is 'hidden' well partially anyway.
You are subject to gravity from all parts of the earth, from horizon to horizon and right through it's depths. Yes you can measure gravity from the sun and the moon, just look at the tides.

Originally Posted by lorddog

put a satillite in space around the earth and see if the gravity pull of the sun is dimished by the blocking of the earth. I know you would have to calculate out of the numbers the diffence in distance from one side of the planet to the other in distance to the sun.

so if the gravity is the same then does gravity bend around the earth or perhaps goes directly through the earth without any measurable interferance.

We have this experiment going on already for billions of years. If this, what you are proposing, were true, we would see such an effect in the tides. However, the phenomena related to this are all well explained with the combined forces of the sun and the moon. Furthermore, there a many low-orbit satellites already flying around the earth. Their orbits would have come out pretty wrong, if such an effect would be present.

And to the LIGO experiment, I guess it was still too cheap - too insensitive - to detect the effects of normal gravitational waves. Maybe only a very dramatic event would have been able to be detected.

Since there are gravitational sources everywhere in the universe, any gravitational wave we try to measure will have been hugely diluted in form by time it reaches us, like a tidal wave one side of an ocean becoming a thousand small waves, many travelling in different directions, on the other side.

Originally Posted by Cyberia

Since there are gravitational sources everywhere in the universe, any gravitational wave we try to measure will have been hugely diluted in form by time it reaches us, like a tidal wave one side of an ocean becoming a thousand small waves, many travelling in different directions, on the other side.

While reading you post I've had two thought coming to my mind, in principle.

The first one was, it's good to know that Newtons gravity, gravitation respectively, was not proven until today. Otherwise one would not undertake such.... what do I know how to call it; undertaking, perhaps?

The second one was, why weren't they trying to detect such waves on earth? Respectively, waves stemming from earth? If they where being there, this surely was a valid argument regarding to emerging cost's and regarding to the time it takes, first of all, as well as, or, since the capacities and resources which the job bounds. Some other business would have gone out of business not ones but many times right now.

Somehow it seems to be a bad joke that a physical law noted down in about 1670 was still in question in 2008. Approximately 330 + years later. Just to give you the relation.

Jules Verne did a better job, I would say.

And, we do not have to be puzzled about living conditions we're facing in a broad extend. There, not even the underpinning was good.

Hopefully I do not ruin folks who research honestly. No, I don't think so.

Steve

Steve Miller. The problem is that while we can work out how bodies will react under forces of gravity, we actually know very little about gravity. It was only recently that we realised it travelled at light speed. We still don't know what it is and while "gravitons" would be convenient for many, most talk about gravity waves now. I don't think we will detect them from distant sources because of so much "pollution" on the way here and the trouble is large masses are needed so not the sort of thing we can do ourselves.

Originally Posted by Cyberia

Steve Miller. The problem is that while we can work out how bodies will react under forces of gravity, we actually know very little about gravity. It was only recently that we realised it travelled at light speed. We still don't know what it is and while "gravitons" would be convenient for many, most talk about gravity waves now. I don't think we will detect them from distant sources because of so much "pollution" on the way here and the trouble is large masses are needed so not the sort of thing we can do ourselves.

Yes, Mr.schoolmaster, if this was true, would you please be so kind to explain to me why space was weightlessly? : )

Steve

To All

Technically, we are in a neutral gravity zone. In other words, the Sun has no influence on our beings because the Earths 'momemrum' has neutralized the Suns gravity.

So the only body that affects us is the Earths gravity.

The Earths tidal waves are just distortions because of the fluid nature of water.

There are supposed to be ever so sightly distortions in the Earths solid matter where variations in the solid matter have slight variations as well.

Cosmo

Technically, we are in a neutral gravity zone. In other words, the Sun has no influence on our beings because the Earths 'momemrum' [sic] has neutralized the Suns gravity.

So the only body that affects us is the Earths gravity.

The Earths tidal waves are just distortions because of the fluid nature of water.

There are supposed to be ever so sightly distortions in the Earths solid matter where variations in the solid matter have slight variations as well.

Cosmo

Hi, Cosmo,
I've got a question. 'Momemrum' was momentum but misspelled, right?

Steve

Originally Posted by Steve Miller

Technically, we are in a neutral gravity zone. In other words, the Sun has no influence on our beings because the Earths 'momemrum' [sic] has neutralized the Suns gravity.

So the only body that affects us is the Earths gravity.

The Earths tidal waves are just distortions because of the fluid nature of water.

There are supposed to be ever so sightly distortions in the Earths solid matter where variations in the solid matter have slight variations as well.

Cosmo

Hi, Cosmo,
I've got a question. 'Momemrum' was momentum but misspelled, right?

Steve

Yes. How did I overlook that.
I always review my spelling because I make errors.
That one got by.
Thanks for the notification.

Cosmo

Originally Posted by Cosmo

To All

Technically, we are in a neutral gravity zone. In other words, the Sun has no influence on our beings because the Earths 'momemrum' has neutralized the Suns gravity.

So the only body that affects us is the Earths gravity.

The Earths tidal waves are just distortions because of the fluid nature of water.

There are supposed to be ever so sightly distortions in the Earths solid matter where variations in the solid matter have slight variations as well.

Cosmo

Cosmo,

but I just keep on thinking weightlessness does not fit in the image we have got of it all. How can this be? Remote objects taking effects on each other spookily? After crossing almost endless weightless regions? I imagine it to be like sound waves you can not hear for several reasons.

Steve

Steve

So the only body that affects us is the Earths gravity.

The Earths tidal waves are just distortions because of the fluid nature of water.

Why then are we able to exactly predict the tides using the relative positions of the sun and moon to the earth?

Originally Posted by Cosmo

To All

Technically, we are in a neutral gravity zone. In other words, the Sun has no influence on our beings because the Earths 'momemrum' has neutralized the Suns gravity.

Only true for the center of mass of the Earth (IOW, the center of the Earth.)

So the only body that affects us is the Earths gravity.


Cosmo

Since very few of us live at the center of the Earth not true.

Example:

The center of the Earth moves at exactly orbital speed for its distance from the Sun. A point on the Earth exactly opposite the Sun makes one orbit in the same time, but traces a path 0.004% longer, and thus travels 0.004% faster. In addition, the proper orbital speed at this distance from the Sun is 0.0064% less than that at the center of the Earth.

Thus an object sitting at a point on the surface of the Earth just opposite the Sun is traveling some 0.014% faster than orbital speed for that distance. As a result is a tendency to climb in to a higher orbit around the Sun. This tendency lessens the effective pull of the Earth's gravity on the object, which results in one of the solar tidal bulges.

On the opposite side of the Earth, the object is tracing out a shorter path and the needed orbital speed is higher, so the tendency is to fall in nearer to the Sun, causing another tidal bulge.

Originally Posted by Steve Miller

The second one was, why weren't they trying to detect such waves on earth? Respectively, waves stemming from earth? If they where being there, this surely was a valid argument regarding to emerging cost's and regarding to the time it takes, first of all, as well as, or, since the capacities and resources which the job bounds. Some other business would have gone out of business not ones but many times right now.


Steve

It sounds like your confusing gravity waves with the force of gravity (don't worry it is a very common confusion among lay-people.)

Gravity waves are not what conveys the gravitational force. The force is due to a field. Gravity waves are more like "ripples" in that field. If you have a mass sitting still, it has a gravitational field, but it is not emitting gravity waves. If you now take and shake that mass back and forth, it will emit gravity. (just like a vibrating charge will emit electromagnetic waves.)

Gravity waves are very very very weak. You have to have quite a large mass to produce detectable ones. You also have to have the mass accelerating at a fast enough rate.( A gravity wave's energy, like a light wave's is inversely proportional to its frequency)

The best source is small compact masses (large voluminous ones tend to smear out the waves) accelerating quickly; something like closely orbiting neutron stars. Unfortunately, we are not close to such sources, and distance also plays a role in detection.

Originally Posted by Janus

Originally Posted by Steve Miller

The second one was, why weren't they trying to detect such waves on earth? Respectively, waves stemming from earth? If they where being there, this surely was a valid argument regarding to emerging cost's and regarding to the time it takes, first of all, as well as, or, since the capacities and resources which the job bounds. Some other business would have gone out of business not ones but many times right now.


Steve

It sounds like your confusing gravity waves with the force of gravity (don't worry it is a very common confusion among lay-people.)

Gravity waves are not what conveys the gravitational force. The force is due to a field. Gravity waves are more like "ripples" in that field. If you have a mass sitting still, it has a gravitational field, but it is not emitting gravity waves. If you now take and shake that mass back and forth, it will emit gravity. (just like a vibrating charge will emit electromagnetic waves.)

Gravity waves are very very very weak. You have to have quite a large mass to produce detectable ones. You also have to have the mass accelerating at a fast enough rate.( A gravity wave's energy, like a light wave's is inversely proportional to its frequency)

The best source is small compact masses (large voluminous ones tend to smear out the waves) accelerating quickly; something like closely orbiting neutron stars. Unfortunately, we are not close to such sources, and distance also plays a role in detection.

I know, I do thank you anyway. I just wanted to delete the last sentence before posting, actually. But I couldn't however. I hit 'Submit' and off it went.

What do you think the gravity or gravitation or gravitational field was existing of? It's a huge force presupposed it's existent. No one really ever saw the field or has other actual evidence. Therefore no one factually ever witnessed the field I mean. Meaning not the effect but the field itself.

Steve

Originally Posted by Steve Miller

Yes, Mr.schoolmaster, if this was true, would you please be so kind to explain to me why space was weightlessly? : )

Steve

In space away from the Earth, the whole universe is pulling at you, but the sources are so far away and so weak that you do not notice them. What we call weight is a concentrated gravitational pull in one direction. In the centre of the Earth, you would weigh nothing.

Originally Posted by Cyberia

In space away from the Earth, the whole universe is pulling at you, but the sources are so far away and so weak that you do not notice them. What we call weight is a concentrated gravitational pull in one direction. In the centre of the Earth, you would weigh nothing.

Don't know, but I think this was pure nonsense. Sorry.

Steve

Originally Posted by Steve Miller

Originally Posted by Cosmo

To All

Technically, we are in a neutral gravity zone. In other words, the Sun has no influence on our beings because the Earths 'momemrum' has neutralized the Suns gravity.

So the only body that affects us is the Earths gravity.

The Earths tidal waves are just distortions because of the fluid nature of water.

There are supposed to be ever so sightly distortions in the Earths solid matter where variations in the solid matter have slight variations as well.

Cosmo

Cosmo,

but I just keep on thinking weightlessness does not fit in the image we have got of it all. How can this be? Remote objects taking effects on each other spookily? After crossing almost endless weightless regions? I imagine it to be like sound waves you can not hear for several reasons.

Steve

Steve

In the center of our Sun, gravity equals 'zero'
This is because objects from all around the outer rim neutralize the central region.
So when surrounded by masses, they pull all around you so their effect is zero.

The major satellites surroudeding the planets, have liquid centers. So their spherical shapes are distorted by the planets gravity just as the tides on our Earth.
This prevents the satellites to spin just as our Moon is distorted by the Earths gravity.

But any gravitational effects on our bodies can be ignored as far as our feelings are concerned.
We have the required momentum to put us in the neutral orbital region of gravities effects from the Sun.

Cosmo

Originally Posted by Janus

Originally Posted by Cosmo

To All

Technically, we are in a neutral gravity zone. In other words, the Sun has no influence on our beings because the Earths 'momemrum' has neutralized the Suns gravity.

Only true for the center of mass of the Earth (IOW, the center of the Earth.)

So the only body that affects us is the Earths gravity.


Cosmo

Since very few of us live at the center of the Earth not true.

Example:

The center of the Earth moves at exactly orbital speed for its distance from the Sun. A point on the Earth exactly opposite the Sun makes one orbit in the same time, but traces a path 0.004% longer, and thus travels 0.004% faster. In addition, the proper orbital speed at this distance from the Sun is 0.0064% less than that at the center of the Earth.

Thus an object sitting at a point on the surface of the Earth just opposite the Sun is traveling some 0.014% faster than orbital speed for that distance. As a result is a tendency to climb in to a higher orbit around the Sun. This tendency lessens the effective pull of the Earth's gravity on the object, which results in one of the solar tidal bulges.

On the opposite side of the Earth, the object is tracing out a shorter path and the needed orbital speed is higher, so the tendency is to fall in nearer to the Sun, causing another tidal bulge.

I am familiar with these tidal actions .
These actions are the reason why our Moon does not spin.
Since t is a round body, that means it has a liquid center.
So my conclusion is that its spherical shape is distorted by these tidal actions. That is why the Moon does not spin.
In other words, the Moon is slightly 'egg' shaped.

Cosmo

Interesting comments so far. Curious, which role do Super massive black holes play in luring and 'capturing' bodies in the heavens?

An article read some weeks back posited that every galaxy, observed so far, in the universe has a massive black hole feeding at it's core. So, with relations to the Sun, are the planets captured by the Sun's gravity field or is this a case of the higher the mass, the more pull it produces; thus, suggesting the planets revolve around a sun-centered galaxy orbiting a black hole? How does one resolve such conflicts with this new finding?

Hello,

I'm not really sure on how this issue was seen officially, but I couldn't think of a galaxy not spiraling around a black hole. Therefore this finding to me was not as new as it was to others perhaps. I also do think I just recall I was taught so while being back in school.

That's why I came to the conclusion any motion in a galaxy was set off by it's black hole. This statement was proven somehow by the spiral-like but planar shape of any galaxy, as far as remember, I have seen by now.

Let's say this was true, then gravity does not have to be the force propelling the solar system which, then again, I think converges with knowledge of weightlessness men have found since traveling to space.

Steve

Originally Posted by koboko

Interesting comments so far. Curious, which role do Super massive black holes play in luring and 'capturing' bodies in the heavens?

An article read some weeks back posited that every galaxy, observed so far, in the universe has a massive black hole feeding at it's core. So, with relations to the Sun, are the planets captured by the Sun's gravity field or is this a case of the higher the mass, the more pull it produces; thus, suggesting the planets revolve around a sun-centered galaxy orbiting a black hole? How does one resolve such conflicts with this new finding?

I was in the process of answering this post when a hacker employed by whom(?) blacked out my monitor screen that forced me to shut down the program and reopen it.

So I have to rewrite my answer again. I have had this problem for a long time and suspect Microsoft Corp. as a possible culprit. I have had this problem for a couple of years that even assasinated my previous W 98 program and my previous computer.
I know I have a case here of violating my FREE SPEECH rights but how do I prove this?
I will post my abswer to this post in the next reply.

Cosmo

Originally Posted by koboko

Interesting comments so far. Curious, which role do Super massive black holes play in luring and 'capturing' bodies in the heavens?

An article read some weeks back posited that every galaxy, observed so far, in the universe has a massive black hole feeding at it's core. So, with relations to the Sun, are the planets captured by the Sun's gravity field or is this a case of the higher the mass, the more pull it produces; thus, suggesting the planets revolve around a sun-centered galaxy orbiting a black hole? How does one resolve such conflicts with this new finding?

As I had written previously, I do not believe in BH's as left over remnants of BG stars.
My opinion is that the final stage of all stars are the neutron stars.
These stars decay into the original elements like the hydrogen gases (electrons and protons) and the stable Alpha particles.

Proof?
This opinion is based on the Gamma Ray Bursters that have been determined to be 'high velocity protons' striking our atmosphere..

Since our planet is a tiny miniscule target in this giagantic universe of ours,
It is obvious that these bursters exist in stupendously high numbers throughout the universe and the only source of these bursters can be the decaying neutron stars that also exist in very high numbers.
The central regions of galaxies must have a high concentration of these stars that would constitute the oldest part of the galaxies and the highest concentration to have the most spent stars as NS's.

Cosmo

alpha particles aren't stable :?

Originally Posted by Steve Miller

Originally Posted by Cyberia

In space away from the Earth, the whole universe is pulling at you, but the sources are so far away and so weak that you do not notice them. What we call weight is a concentrated gravitational pull in one direction. In the centre of the Earth, you would weigh nothing.

Don't know, but I think this was pure nonsense. Sorry.

Steve

Why do you think it is nonsense, Steve? http://en.wikipedia.org/wiki/Shell_theorem

That's why I came to the conclusion any motion in a galaxy was set off by its black hole. This statement was proven somehow by the spiral-like but planar shape of any galaxy, as far as remember, I have seen by now.

Where do you think the black hole came from? Black holes retain their angular momentum, which would be in the same direction as the orbiting stars and clouds, since it from this material that the black hole was formed out of in the first place. If the sun somehow became a black hole, it would retain its angular momentum and the planets would keep revolving as usual. Roughly the same happens with galactic core black holes.

AFAIK

because force is inversely proportional to distance r^2 then each time the distance doubles the force square roots.
When you reach the surface the gravity is at it's maximum because you have to take mass into effect and as you go into the planet the mass decreases so you get a graph like this:



(ignore the work done part as it was the only graph I could find )

Originally Posted by Steve Miller

Originally Posted by Cyberia

In space away from the Earth, the whole universe is pulling at you, but the sources are so far away and so weak that you do not notice them. What we call weight is a concentrated gravitational pull in one direction. In the centre of the Earth, you would weigh nothing.

Don't know, but I think this was pure nonsense. Sorry.

Steve

You are entitled to your opinions though I prefer reasons.

Originally Posted by Cyberia

Originally Posted by Steve Miller

Originally Posted by Cyberia

In space away from the Earth, the whole universe is pulling at you, but the sources are so far away and so weak that you do not notice them. What we call weight is a concentrated gravitational pull in one direction. In the centre of the Earth, you would weigh nothing.

Don't know, but I think this was pure nonsense. Sorry.

Steve

You are entitled to your opinions though I prefer reasons.

Since you were referring to some distant sources which you cited. That's no more adventurous but sheer nonsense to say it again. And from my perspective, I don't expressed an opinion.

@KALSTER
I think a black hole will form when a star dies in fact. But, since there are other planets, objects etc. orbiting the star through space which will not receive the amount of energy that they did before and even not so space itself that they forward through, there will rip a tear into space (where the star ones was ) which was the begin of the black hole, I think.

Steve

Originally Posted by Nevyn

alpha particles aren't stable :?

You may be right but I concluded their existance because of the helium gases in space that are detected.
They can easily form helium gas because there are large numbers of free
electrons in space that out number the Gamma Ray protons by a sizeable number.

Cosmo