Air and gravity

[weknowthewor]

Hello,

 

I have a question in mind that is there no effect of gravity on air bcaz air can move in any direction...

[swansont]

I can move in any direction and gravity affects me.

 

Air density and pressure falls off with vertical distance, like you'd expect, from the interaction with gravity.

[jck]

This is more complicated than the over view would suggest.

 

An atom in the air is an atom in the air no matter what the vertical distance may be, so gravity would affect each atom the same way. With curved space gravity all the atoms should ground.

 

With differential particle gravity the density factors would be correct.

 

john

jck

[TriggerGrinn]

a star is made of air (that is, matter, gas, etc etc) and it has gravity.

[Edtharan]

I have a question in mind that is there no effect of gravity on air bcaz air can move in any direction...

If air is not subject to gravity, then why dose it hang around Earth at all. There is plenty of space that it could move into, so why hasn't it move there?

 

The answer is of course that it is subject to gravity and the gravity of the earth keeps it close.

[SkepticLance]

I am a scuba diver, and I have very convincing and totally practical proof that gravity affects air. Weight comes from gravity. When I carry a scuba tank full of compressed air, it is damned heavy! When it has been used, and there is hardly any air left in it, it is remarkably light in weight.

 

Oh yes, air has weight, and thus is affected by gravity.

[swansont]

An atom in the air is an atom in the air no matter what the vertical distance may be, so gravity would affect each atom the same way. With curved space gravity all the atoms should ground.

 

Air molecules are moving very fast, so they bounce. Energy keeps getting added from thermal sources. This keeps them from all settling.

[jck]

A star is burning hydrogen. The air is not drifting into space but whether that is due to the curved space around the earth is not certain. A scuba tank is not opened and then gravity forces the air to be compressed, a force is applied to compress that.

 

Thermal sources must affect all atoms, this must defy the force of gravity to keep them from grounding. There is no question that air does not ground but the reason may not be simply what is observed and attributed.

 

john

jck

[swansont]

They don't have to defy anything. The behavior is explained by the existing laws.

[insane_alien]

remove the heat source and the air will condense (ground) its how we get bottles of nitrogen and oxygen (and most of the other bottled inert gases)

[jck]

Everything is explained by existing observational assumptions, unless these explanations are certain and will at no time be refuted there is room for debate. I am not saying it is incorrect only that it is not exactly certain either.

 

Am I to assume that removing the heat source will ground all the air in a particular place? There are places on earth with no airspace?

 

john

jck

[CPL.Luke]

no, but there are places on earth with no heat in them.

 

the only places that come close to that are in various condensed matter labs.

[swansont]

Everything is explained by existing observational assumptions, unless these explanations are certain and will at no time be refuted there is room for debate. I am not saying it is incorrect only that it is not exactly certain either.

 

This is not how science works; science does not convey 100% certainty. It can't, as it is inductive. One proceeds by attempting to disprove the theories, so you would need to find where current theories predict one behavior but another is observed.

[jck]

swansont,

 

Well I am happy for science to work the way it does but I do not work that way, there is no reason everyone should accept the restricted practice of scientific methodolgy.

 

What is actually required is some means to compare to theory just in case the absence of logic in many theoretical considerations are self inflicted. If that happens to be a logic based solution then that would seem appropriate to me.

 

As much as it is touted that predications are made by theory without the observational assumptions being involved in the first place such predictions are not possible so it questions whether the theory is made to fit the observations rather than observation confirming the theory as we are led to believe.

 

There is a place for theory, in fact it is given the bulk of forum space on here, but it is not the be all end all unless everyone agrees it is correct. At this time the majority have severe problems with much of the theory even among the accademics.

 

I am perfectly happy for you to use theory and scientific method but myself would prefer a logical answer.

 

john

jck

[swansont]

swansont,

 

Well I am happy for science to work the way it does but I do not work that way, there is no reason everyone should accept the restricted practice of scientific methodolgy.

 

What is actually required is some means to compare to theory just in case the absence of logic in many theoretical considerations are self inflicted. If that happens to be a logic based solution then that would seem appropriate to me.

 

As much as it is touted that predications are made by theory without the observational assumptions being involved in the first place such predictions are not possible so it questions whether the theory is made to fit the observations rather than observation confirming the theory as we are led to believe.

 

There is a place for theory, in fact it is given the bulk of forum space on here, but it is not the be all end all unless everyone agrees it is correct. At this time the majority have severe problems with much of the theory even among the accademics.

 

I am perfectly happy for you to use theory and scientific method but myself would prefer a logical answer.

 

john

jck

 

Well, you are free to do something else other than science. Many people do; they believe in astrology, or prayer or something else. Derive the universe from first principles, if it is within your skills. But within the scientific realm, you have to follow the practices of science.

 

It's unclear from your use of "theory" if you are using it in the scientific sense, nor from your use of "logical" what that means. There are things in science that are counterintuitive from a classical standpoint. But there is nothing that guarantees that workings of nature have to make sense. One can argue that QM and relativity are not logical from the perspective of everyday, classical, macroscopic experience, (and I would agree) but that carries no weight in any argument. It's how nature behaves.

[jck]

swansont,

 

Science is not the theory or the method theory uses, it is the actual matter in the actual universe. Now science may claim to have the best answers given the observational data but if the very assumptions of that observational data is questioned it can hardly be questioned using the same theoretical assumptions that supports it can it?

 

Take for example the space question?

 

Science can obtain no information before big bang so you would expect science to keep out of that issue but no we find there are theoretical only explanations why there could be a universe without there being any space before big bang.

 

Now I ask you what right has science got to decide there was no space before big bang, none at all thats what right it has. However it hedges its bets by stating that science does not state there was no space before big bang.

 

Science also states that anything before the universe would be of no value as everything was reduced to energy at big bang anyway. That assumes that there is no space outside the universe, which again science cannot state with any certainty at all, leaving the possibility that the universe is simply a speck in an endless space outside and before big bang.

 

Do you consider asking the question what was here before the universe as not being science? Do you consider asking is there space outside the universe not being science?

 

That is science deciding what is and what is not science, not exactly healthy is it?

 

There is absolutely space in the universe which does not need any proof and there is no way anyone can show by experiment how space can not exist without leaving a space. No one has ever created space using energy have they? Yet the theory has the energy at big bang creating the space? Is that science?

 

So you see there is a lot to be desired for anyone actually trying to understand the universe that science has simply ignored or presented an unfounded theoretical solution to explain something.

 

It is close to the opposite view, the more science relies on theory especially mathematical models the less regard it receives.

 

You will find it is those studying theory for a degree or employed using the theory that support it without question, one cannot step outside the theory if it results in losing a degree or employment.

 

The space question is science more than anything else, one might ask whether theoretical models are science or whether geometry is science.

 

No one can ever prove empty space can curve, it cannot be done and yet that is so called science.

 

So science is as far as the universe is concerned trying to find out what is correct and what is wrong and by blindly using theory to support theory I do not see what result that can have but to support the theory or alter the theory and then say it is correct.

 

john

jck

[SkepticLance]

jck

I hate to have to say this, but ...

Your last posting basically says nothing except that anything you cannot understand cannot be science because you cannot understand it.

 

I admit to not understanding quantum chromodynamics. However, my lack of understanding does not lead me to say it cannot be science. I know it is science, because those who study this subject make testable predictions, which fail to be falsified when tested, even after repeated testing. That is pretty much the definition of science.

 

Those who study cosmology also use their understanding to make testable predictions. When, as is usually the case, they fail to be falsified by empirical testing, this is science.

 

Trying to find out what happened 'before' the Big Bang can be science. Speculation is not science, but an attempt to discover new material pertinent to that question may well be good science.

[swansont]

It is now clear that you don't understand what a scientific theory really is. Fortunately, you can rectify that.

 

I agree with SkepticLance's prognosis; you suffer from a form of the "If I don't understand it it's wrong" syndrome.

[insane_alien]

jck, reality doesn't care what you think or cannot understand and neither does science since it reflects and models reality. nor does it just take on crackpot ideas like relativity just like that.

 

You see, lots of people couldn't understand it so they called it BS, then they took a look at reality and seen that thats what was happening so THEN they accepted it.

 

if you looked at the evidence(or even done a few experiments of your own you'd see that the theories are right)

[jck]

Skeptic,

 

Then empty space in isolation can be shown to curve as accordingly it must be testable to be science?

 

Swansont,

 

Scientific theory has a multi observer viewpoint correct and a single observer viewpoint wrong. Scientific theory has particles popping in and out of the universe when no one knows what out of the universe means. Scientific theory has empty space curving when that can only be attributed via light deflecting and not the empty space. Scientific theory has mathematics that are theoretical and as long as no one can refute those mathematics they stand as science theory. All this may well be correct but unless attempts are made to formulate other means for comparing theory then it is a self preservation society.

 

Insane,

 

I fail to see why those who accept the theory is the only science they can understand would be on the speculation boards here? Either you accept the theories are 100% correct or you are looking for other possibilities which is all that I am doing.

 

Theory can consider any other possibilities as wrong providing the theory can maintain that the theory is 100% correct, ideas will not suddenly remove the theories will they so why is everyone so concerned that others put forward other possibilities?

 

Basically everyone is saying that only theory is allowed on the speculation boards? Anything that is not in full agreement with theory must be wrong and is not science? Then you are all entitled to that view which I respect but do not agree with at all.

 

john

jck

[SkepticLance]

jck said :

 

Then empty space in isolation can be shown to curve as accordingly it must be testable to be science?

 

The scientific method requires that hypotheses must be testable using empirical methods. This is done by making a prediction based on the hypothesis, and then running a real world experiment or observation to see if that prediction holds.

 

In the case of your question, Einstein came up with the hypothesis that space curves around objects that have mass, with more curving when there is more mass. A prediction that was made from this is that light will bend with the curving of space. This is observable, and has been observed. Thus, the requirement of science has been met, and Einsteins hypothesis has stood that test.

 

This phenomenon has even been put to practical use, with large mass objects in space being used as gravity lenses, to curve light towards us, revealing objects that are otherwise invisible.

[swansont]

Scientific theory has a multi observer viewpoint correct and a single observer viewpoint wrong. Scientific theory has particles popping in and out of the universe when no one knows what out of the universe means. Scientific theory has empty space curving when that can only be attributed via light deflecting and not the empty space.

 

I don't understand what you mean here.

 

Scientific theory has mathematics that are theoretical and as long as no one can refute those mathematics they stand as science theory. All this may well be correct but unless attempts are made to formulate other means for comparing theory then it is a self preservation society.

 

Examples? Scientific theory is always backed up by data. If it isn't, it's not a theory.

 

 

I fail to see why those who accept the theory is the only science they can understand would be on the speculation boards here? Either you accept the theories are 100% correct or you are looking for other possibilities which is all that I am doing.

 

Theory can consider any other possibilities as wrong providing the theory can maintain that the theory is 100% correct, ideas will not suddenly remove the theories will they so why is everyone so concerned that others put forward other possibilities?

 

Basically everyone is saying that only theory is allowed on the speculation boards? Anything that is not in full agreement with theory must be wrong and is not science? Then you are all entitled to that view which I respect but do not agree with at all.

 

What's the motivation to replace an existing theory if it explains a particular phenomenon? If it's wrong, you have to show that it's wrong. If you want to replace it, your replacement has to explain all that current theory already explains, and more beyond that, or be simpler.

[jck]

Skeptic,

 

Exactly! This is a test for light but with no actual test for the space itself as an entity. It is "if" space curves it could be shown by geometry to account for light bending. I am not questioning light bending, I am questioning space doing anything at all. The phenomenom is light bending

not space curving.

 

swansont,

 

I do not understand what you do not understand in the first quote.

 

Read the reply to Skeptic for an example of space itself curving having no data but the data for light bending is simply attributed anyway.

 

I have not replaced any theory, I do not have a theory to replace any theory.

 

What I have is an alternative solution based on space and energy existing before big bang with which to compare to the theories, as there are only two choices regarding space and energy existing or not existing before big bang it seems to me that both should be taken into consideration.

 

Theory does not establish a certain space and energy before big bang, my solution does as if the theories are wrong about it then I will certainly be right. Anyone not willing to consider space and energy before big bang are gambling that there wasn`t or if there was it makes no difference.

 

It makes a big difference, the theories cannot be correct if there was space and energy before big bang, anyone wishing to disregard this slight problem and accept the theories as absolutely correct are entitled to think that.

 

john

jck

[swansont]

Exactly! This is a test for light but with no actual test for the space itself as an entity. It is "if" space curves it could be shown by geometry to account for light bending. I am not questioning light bending, I am questioning space doing anything at all. The phenomenom is light bending

not space curving.

 

But we understand conditions under which light bends. Refraction, for example, does not account for it, as there is little material present and the index is much smaller than is needed. And the amount of bending is what is predicted by relativity.

 

Read the reply to Skeptic for an example of space itself curving having no data but the data for light bending is simply attributed anyway.

 

I have not replaced any theory, I do not have a theory to replace any theory.

 

What I have is an alternative solution based on space and energy existing before big bang with which to compare to the theories, as there are only two choices regarding space and energy existing or not existing before big bang it seems to me that both should be taken into consideration.

 

No theory but an alternative solution? Is there something here beyond semantics that I'm missing?

 

Theory does not establish a certain space and energy before big bang, my solution does as if the theories are wrong about it then I will certainly be right. Anyone not willing to consider space and energy before big bang are gambling that there wasn`t or if there was it makes no difference.

 

It makes a big difference, the theories cannot be correct if there was space and energy before big bang, anyone wishing to disregard this slight problem and accept the theories as absolutely correct are entitled to think that.

 

Have done a comprehensive search of the literature to ensure that this hasn't already been addressed?

[SkepticLance]

jck

Addressing the statment that :

light bending = space bending

 

This is an example of the predictive principle of science in action.

That is : when a scientist formulates a hypothesis as a possible explanation for something, that hypothesis must lead to testable predictions.

 

Einstein formulated his hypothesis of gravity, caused by the bending of space. He then made predictions based on this hypothesis. Light bending around a massy object was one prediction. It was tested and found to be correct.

 

This is not, of course, absolute proof. But science does not operate on absolute proof since no such thing exists. It operates on the falsification principle. Repeated attempts are made to falsify a scientific idea. This is done by prediction and empirical testing. If repeated attempts to falsify an idea fail to do so, then the idea is accepted as a good model of reality.

 

This is the status of the idea that space bends, causing gravity. Many experiments and novel observations have been carried out to attempt to disprove this idea. They have failed. Thus we accept that Einstein's idea is a good model.

 

If you have a 'better' idea, then you must make testable predictions, and put it to the test. Try to falsify the idea. If you cannot, it may have merit.