Lets talk again about gravity

Like I said show me were Einstein said gravitation is acceleration.

So what people standing on the surface of the Earth perceive as the 'force of gravity' is a result of their undergoing a continuous physical acceleration caused by the mechanical resistance of the surface on which they are standing.

Like I said, if you had bothered to do any research, you would have known this.

http://en.wikipedia.org/wiki/General_relativity#Gravitation
Here, do some reading, before you post again.

Quote

*points Tom at her post about referees*

Yes, I saw it. Thanks for pointing it out again.
Unfortunately cameras were not around 150 years ago. We only have the word of three people: John Hampden, the referee William Carpenter, and Alfred Wallace. Two of those people came away from the experiment saying that the earth was proven flat.

Quote

Besides that: De Morgan, though famous, was a mathematician, not a scientist. Please try again though!

Mathematicians are most certainly considered scientists. Is math not a science, somehow?

Science is not about individuals. The exact events of that day are unimportant. If an experiment is repeatedly done with conclusions pointing both sides, as this one allegedly is, you have to improve it and get good answers. Just by increasing the distance between the flags to 10 or 20 miles conclusive answers will be easy to get. Of course, this is just one of dozens of experiments that give evidence to RE, and FE proponents still have not showed a model, a formula, a prediction, or anything even resembling science.

Quote from: Tom Bishop on June 05, 2007, 03:50:51 PM

Quote

*points Tom at her post about referees*

Yes, I saw it. Thanks for pointing it out again.
Unfortunately cameras were not around 150 years ago. We only have the word of three people: John Hampden, the referee William Carpenter, and Alfred Wallace. Two of those people came away from the experiment saying that the earth was proven flat.

Quote

Besides that: De Morgan, though famous, was a mathematician, not a scientist. Please try again though!

Mathematicians are most certainly considered scientists. Is math not a science, somehow?

Science is not about individuals. The exact events of that day are unimportant. If an experiment is repeatedly done with conclusions pointing both sides, as this one allegedly is, you have to improve it and get good answers. Just by increasing the distance between the flags to 10 or 20 miles conclusive answers will be easy to get. Of course, this is just one of dozens of experiments that give evidence to RE, and FE proponents still have not showed a model, a formula, a prediction, or anything even resembling science.

I'd augment your excellent point if you permit. In science, we must be willing to roll up our sleeves and experiment. If we don't have confidence in a result, if someone else doesn't have confidence, we go into the field. I've leveled a challenge to TomB to document with proper verification his claimed view across the bay near his home. I've ordered a telescope to reproduce the experiment myself.

I've leveled a challenge to everyone to download SunSpots.xlsx and look at how FE's and RE's predictions differ and to compare them with their own observations over several hours , several day, and several months. Let's not be afraid of getting our hands dirty.

My name implies what?  That I'm an engineer?  Yea, that's the point.  But still, when did it become my job to make models and numbers for you RE'ers?

Do not make models for us RE proponents. We have plenty, and they work fine, thank you. Make some, please, for FE proponents, who cannot even predict the apparent size of the sun for different hours of the day, something that has been a no-brainer since the Mesopotamians started the first civilization.

You cannot be an Engineer (someone who deserves the title, anyway) and not ask yourself why FE hypothesis are woefully lacking anything resembling precision.

Quote from: sokarul on June 05, 2007, 08:57:56 PM

Like I said show me were Einstein said gravitation is acceleration.

Quote

So what people standing on the surface of the Earth perceive as the 'force of gravity' is a result of their undergoing a continuous physical acceleration caused by the mechanical resistance of the surface on which they are standing.

Like I said, if you had bothered to do any research, you would have known this.

http://en.wikipedia.org/wiki/General_relativity#Gravitation
Here, do some reading, before you post again.

If orbit is acceleration and gravitation is acceleration then that means orbit is gravitation.  So once again I get to use the word gravitationing, so a satellite is gravitationing above the earth.  Gravitation is the act of to objects wanting to go towards each other. There would be no need to come up with the equivalence principle if gravitation was acceelration.  

You cannot be an Engineer (someone who deserves the title, anyway) and not ask yourself why FE hypothesis are woefully lacking anything resembling precision.

Who says I haven't?  Or do you need reading lessons too?

There would be no need to come up with the equivalence principle if gravitation was acceelration.   

The whole point of the Equivalence Principle is to arrive at the fact that gravitation is acceleration. 

Quote from: sokarul on June 05, 2007, 09:39:15 PM

There would be no need to come up with the equivalence principle if gravitation was acceelration.   

The whole point of the Equivalence Principle is to arrive at the fact that gravitation is acceleration. 

No its to say you cant tell them apart.  Not to arrive that they are the same thing.  And thats why the EP does not apply to non uniform gravitaitonal fields. 

Too bad for you the EP is the basis for GR.  Please read the stuff in the link before you post again.

Too bad for you the EP is the basis for GR.  Please read the stuff in the link before you post again.

Oh i did.  I had already quoted it before you posted it.  I have also read Tom's(of all peoples) link to a paper on GR.   

Quote from: TheEngineer on June 05, 2007, 09:42:47 PM

Quote from: sokarul on June 05, 2007, 09:39:15 PM

There would be no need to come up with the equivalence principle if gravitation was acceelration.   

The whole point of the Equivalence Principle is to arrive at the fact that gravitation is acceleration. 

No its to say you cant tell them apart.  Not to arrive that they are the same thing.  And thats why the EP does not apply to non uniform gravitaitonal fields. 

Once again, The Engineer forgot that the Equivalence Principle is only valid locally!!! If you have a system with more than one large mass you will have gravitational forces in more than one direction and objects accelerating in more than one direction, and both will be clearly distinguishable from each other.
You have to close your eyes and not look at the sky if you really want to keep the "local" part of the principle alive. As soon as you ask yourself why the sun travels the sky the way it does, and figure out that there are forces and acceleration involved, and furthermore they are not "local", your bubble suddenly bursts.
There is a sea of difference between "gravitation is acceleration" and "gravitation is indistinguishable from acceleration locally".

Quote from: sokarul on June 05, 2007, 09:45:20 PM

Quote from: TheEngineer on June 05, 2007, 09:42:47 PM

Quote from: sokarul on June 05, 2007, 09:39:15 PM

There would be no need to come up with the equivalence principle if gravitation was acceelration.   

The whole point of the Equivalence Principle is to arrive at the fact that gravitation is acceleration. 

No its to say you cant tell them apart.  Not to arrive that they are the same thing.  And thats why the EP does not apply to non uniform gravitaitonal fields. 

Once again, The Engineer forgot that the Equivalence Principle is only valid locally!!! If you have a system with more than one large mass you will have gravitational forces in more than one direction and objects accelerating in more than one direction, and both will be clearly distinguishable from each other.
You have to close your eyes and not look at the sky if you really want to keep the "local" part of the principle alive. As soon as you ask yourself why the sun travels the sky the way it does, and figure out that there are forces and acceleration involved, and furthermore they are not "local", your bubble suddenly bursts.
There is a sea of difference between "gravitation is acceleration" and "gravitation is indistinguishable from acceleration locally".

Let's turn this into a different debate. Since FE says the effect of gravity is caused by the UA accelerating the FE, and RE says its an effect of the RE's mass, we should be able to detect which is correct by looking for the non-local discrepancies with the Equivalence Principle. Can we build evidence, especially experimental evidenced, to determine which model is better?

Once again, The Engineer forgot that the Equivalence Principle is only valid locally!!! If you have a system with more than one large mass you will have gravitational forces in more than one direction and objects accelerating in more than one direction, and both will be clearly distinguishable from each other.
You have to close your eyes and not look at the sky if you really want to keep the "local" part of the principle alive. As soon as you ask yourself why the sun travels the sky the way it does, and figure out that there are forces and acceleration involved, and furthermore they are not "local", your bubble suddenly bursts.
There is a sea of difference between "gravitation is acceleration" and "gravitation is indistinguishable from acceleration locally".

Good Lord, you people are stupid.  I know that the EP is only valid locally.  I've stated this hundreds of times.  General Relativity states that gravitation is acceleration.  Look it up, for the love of God!

I'm gonna start keeping a tally of how many times this "debate" happens

I've stated this hundreds of times.  General Relativity states that gravitation is acceleration.  Look it up, for the love of God!

I do not know where you learned your physics, but with or without the effects that happen at speeds approaching the speed of light, forces are not changes in velocity, net forces cause changes in velocity. Force equals mass times acceleration, and one of the forces is gravity. Physics is not for those keen on generalizations and games of words.
You say "look it up", so you must have a book of physics that has the three words "gravitation is acceleration". So please, please, please send me the reference!
There is an art where those plays of words are highly appreciated, but it is called rhetoric, not physics, and it is not taught to engineers, maybe to language majors.

Quote from: TheEngineer on June 05, 2007, 11:04:11 PM

I've stated this hundreds of times.  General Relativity states that gravitation is acceleration.  Look it up, for the love of God!

I do not know where you learned your physics, but with or without the effects that happen at speeds approaching the speed of light, forces are not changes in velocity, net forces cause changes in velocity. Force equals mass times acceleration, and one of the forces is gravity. Physics is not for those keen on generalizations and games of words.
You say "look it up", so you must have a book of physics that has the three words "gravitation is acceleration". So please, please, please send me the reference!
There is an art where those plays of words are highly appreciated, but it is called rhetoric, not physics, and it is not taught to engineers, maybe to language majors.

Stop posting!

Good Lord, you people are stupid.  I know that the EP is only valid locally.  I've stated this hundreds of times.  General Relativity states that gravitation is acceleration.  Look it up, for the love of God!

General Relativity (or the Equivalence Principle) states that we can not distinguish by any experiment performed locally between a uniformly accelerated motion in free space and being at rest in a gravitation field, to be exact.

Why can't everyone just go and be at rest in a Gravitational field? I know I am.

Quote from: TheEngineer on June 05, 2007, 11:04:11 PM

Good Lord, you people are stupid.  I know that the EP is only valid locally.  I've stated this hundreds of times.  General Relativity states that gravitation is acceleration.  Look it up, for the love of God!

General Relativity (or the Equivalence Principle) states that we can not distinguish by any experiment performed locally between a uniformly accelerated motion in free space and being at rest in a gravitation field, to be exact.

My same remark applies to you. It is the Equivalence Principle, not the General Relativity which states that we can not distinguish by any experiment performed locally between a uniformly accelerated motion in free space and being at rest in a gravitation field.

Physics is an exact science, and the fact that Einstein worked on the Equivalence Principle in no way implies that General Relativity states the same as the Equivalence Principle.

You did not even touch the real issue, that is that gravitation is not the same as acceleration and that because of the nasty "locally" word in your statement, truth is that in many cases you can distinguish between a uniformly accelerated motion in free space and being in a gravitation field! You just have to observe simultaneously more than one location with different gravitation fields.

If you like analogies, similarities and subjective comparisons, you should stick to Modern Languages.

Hey Max,

I've always wondered, what mechanism causes mass to bend space-time? How does it work?

If you claim that gravity is a force, how does that work?

As an expert in gravity, this should be a simple one for you.

Metter and energy are the same. It can be demonstrated in nuclear reaction(where metter becomes energy) and when you take two quarks and move them from each other(when energy becomes new quarks).

Be can describe the space as a mixture of metter and energy. The space is the backgound of the time and the time is the background of the space. Both of them are combine in a way that influence on the other. When the space changes the time is changes too and when the time changes the space changes as well. We can see evidence for this theory when we look through telescopes on "gravitational lenses".

Be can describe the space as a mixture of metter and energy. The space is the backgound of the time and the time is the background of the space. Both of them are combine in a way that influence on the other. When the space changes the time is changes too and when the time changes the space changes as well. We can see evidence for this theory when we look through telescopes on "gravitational lenses".

So the change in time is...responsible for gravitational lensing?  That's a new one.

Quote from: DelbariTal on June 06, 2007, 02:09:05 PM

Be can describe the space as a mixture of metter and energy. The space is the backgound of the time and the time is the background of the space. Both of them are combine in a way that influence on the other. When the space changes the time is changes too and when the time changes the space changes as well. We can see evidence for this theory when we look through telescopes on "gravitational lenses".

So the change in time is...responsible for gravitational lensing?  That's a new one.

The change of the matter changes the space itself

Right, so it's not time after all.

I do not know where you learned your physics, but with or without the effects that happen at speeds approaching the speed of light, forces are not changes in velocity, net forces cause changes in velocity.  Force equals mass times acceleration, and one of the forces is gravity.

You mean pseudo force, right?  Gravity as a force does not exist.  It arises from transforming a noninertial frame of reference into an inertial one.  Newton's laws do not apply to a noninertial frame of reference.

You say "look it up", so you must have a book of physics that has the three words "gravitation is acceleration". So please, please, please send me the reference!

Let's stick to your inertial frame.  You said F=m*a.  What is the force applied to something of a mass at rest in a gravitational field?  What do you use as a?  That's right, the acceleration due to gravitation.  But the object is not accelerating.  How can that be according to you?

Here are some quotes for you to read over.  They may aid in your understanding.

, the effects of gravitation are ascribed to spacetime curvature instead of to a force. The starting point for general relativity is the equivalence principle, which equates free fall with inertial motion. The issue that this creates is that free-falling objects can accelerate with respect to each other. In Newtonian physics, no such acceleration can occur unless at least one of the objects is being operated on by a force (and therefore is not moving inertially).

To deal with this difficulty, Einstein proposed that spacetime is curved by matter, and that free-falling objects are moving along locally straight paths in curved spacetime. (This type of path is called a geodesic). More specifically, Einstein discovered the field equations of general relativity, which relate the presence of matter and the curvature of spacetime and are named after him. The Einstein field equations are a set of 10 simultaneous, non-linear, differential equations. The solutions of the field equations are the components of the metric tensor of spacetime.

 

In scientific terminology gravitation and gravity are distinct. "Gravitation" is the attractive influence that all objects exert on each other, while "gravity" specifically refers to a force which all massive (objects with mass) objects are theorized to exert on each other to cause gravitation. Although these terms are interchangeable in everyday use, in theories other than Newton's, gravitation is caused by factors other than gravity. For example in general relativity, gravitation is due to spacetime curvatures which causes inertially moving objects to tend to accelerate towards each other.

One of the defining features of general relativity is the idea that gravitational 'force' is replaced by geometry. In general relativity, phenomena that in classical mechanics are ascribed to the action of the force of gravity (such as free-fall, orbital motion, and spacecraft trajectories) are taken in general relativity to represent inertial motion in a curved spacetime. So what people standing on the surface of the Earth perceive as the 'force of gravity' is a result of their undergoing a continuous physical acceleration caused by the mechanical resistance of the surface on which they are standing.

One of the greatest sources of confusion about general relativity comes from the need to distinguish between coordinate and physical accelerations.

In classical mechanics, space is preferentially mapped with a Cartesian coordinate system. Inertial motion then occurs as one moves through this space at a constant coordinate rate with respect to time. Any change in this rate of progression must be due to a force, and therefore a physical and coordinate acceleration were in classical mechanics one and the same. It is important to note that in special relativity that same kind of Cartesian coordinate system was used, with time being added as a fourth dimension and defined for an observer using the Einstein synchronization procedure. As a result, physical and coordinate acceleration correspond in special relativity too, although their magnitudes may vary.

In general relativity, the elegance of a flat spacetime and the ability to use a preferred coordinate system are lost (due to stress-energy curving spacetime and the principle of general covariance). Consequently, coordinate and physical accelerations become sundered. For example: Try using a polar coordinate system in classical mechanics. In this case, an inertially moving object which passes by (instead of through) the origin point is found to first be moving mostly inwards, then to be moving tangentially with respect to the origin, and finally to be moving outwards, and yet it is moving in a straight line. This is an example of an inertially moving object undergoing a coordinate acceleration, and the way this coordinate acceleration changes as the object travels is given by the geodesic equations for the manifold and coordinate system in use.

Another more direct example is the case of someone standing on the Earth, where they are at rest with respect to the surface coordinates for the Earth (latitude, longitude, and elevation) but are undergoing a continuous physical acceleration because the mechanical resistance of the Earth's surface keeps them from free-falling.

I'm not sure why you wont except that matter bends spacetime.  When I throw a ball across my basement its going in a straight line, but since the coordinate system is not int he shape as what you think, its bent.I highly doubt you even know whats being said in the last quote.  I myself like quote two and how it proves you wrong. 
"gravitation is due to spacetime curvatures which causes inertially moving objects to tend to accelerate towards each other", classic.


I'm not sure why you wont except that matter bends spacetime.  When I throw a ball across my basement its going in a straight line, but since the coordinate system is not int he shape as what you think, its bent.   

I'm not sure why you wont except that matter bends spacetime.   

You are so freakin' blind, this has gone beyond annoying.  Your idiocy is what is blocking you from seeing what is in those quotes.

Quote from: sokarul on June 06, 2007, 07:18:06 PM

I'm not sure why you wont except that matter bends spacetime.   

You are so freakin' blind, this has gone beyond annoying.  Your idiocy is what is blocking you from seeing what is in those quotes.

@cry

Your idiocy is what is blocking you from seeing what is in those quotes.

Can you call me "Idiot" too? I want to be called idiot by a guy who believes that the earth is flat

I want to be called idiot by a guy who believes that the earth is flat

   Good ol' new guys.

Quote from: TheEngineer on June 06, 2007, 08:35:28 PM

Your idiocy is what is blocking you from seeing what is in those quotes.

Can you call me "Idiot" too? I want to be called idiot by a guy who believes that the earth is flat

TheEngineer is a REer who likes to wield his knowledge for his own amusement at your expense.