Some questions for better understanding of Main Stream Cosmology

First, I believe you are confusing the concepts of "space" and "spacetime". To be honest I have seen times where even those who know the difference use the words in a confusing manner, but generally they are speaking to others who understand...

The use of the two statements by Rajesh, was and is just a "red herring" raised to confuse even more the confusing picture of spacetime curvature that he has.
origin reputation and knowledge is known by most reputable members and although his phrase may not have been perfect, in this instant, it was raised for the reasons I have stated.



It is difficult to separate descriptions of spacetime curvature from gravitation, but that does not really mean that either one causes the other. You can think of the two as the same thing, in different words.., and still not know the fundamental why of, or how gravitation emerges from the presence of mass.

We certainly do not know the how and why of gravity, but just as certainly, we do know that gravity exhibits its presence when spacetime warps/curves in the presence of mass/energy.
Like all scientific models, the object is to describe what we see, and the question of reality remains open.



They are both abstract concepts, relative to everyday experience. It has really only been since the developement of high precision clocks and things like the GPS system that we have any practical examples of time dilation, what I believe you are referring to as time distortion... And we still have no direct evidence of length contraction. These two together play a large role in what is usually meant by curvature of spacetime, though spacetime cuvature gets even more complicated and involved than just time dilation and length contraction.

I disagree strongly.
Firstly space and time which has come to be known as spacetime with the advent of relativity, are terms that are interchangible and I see nothing wrong or confusing in doing that.
Secondly spacetime, is real and as I have mentioned, has been measured with GP-B.

I also see time dilation and length contraction as real and dispute your inference that we have no evidence for length contraction, common sense and logic tells a different story.
In any experiment with two FoR's and the speed of light, if both frames happen to disagree on time, then it must be inevitable that they also disagree on lengths, to both parties to agree to the fact that the speed of light is constant.

Although Sean only talks of the reality of time in the following link, it is reasonable to extrapolate that to the fact that space, spacetime are also real.
http://www.preposterousuniverse.com/blog/2013/10/18/is-time-real/
 
Though there could be a relativistic argument on the issue, space should most often not be thought of as curved and/or distorted by the presence of mass. Spacetime is a different animal and is a construct composed of more than one part, including, but perhaps not limited to, "space", "time" and even "energy". The balance of how those components of spacetime interact dynamically, both with each other and any local mass, generates what is referenced as spacetime curvature. That curvature describes the gravitational field...
It is difficult to separate descriptions of spacetime curvature from gravitation, but that does not really mean that either one causes the other. You can think of the two as the same thing, in different words.., and still not know the fundamental why of, or how gravitation emerges from the presence of mass.
Space, time, [henceforth called spacetime] is always warped in the presence of mass/energy.
When that happens, we have an effect we call gravity.
It is then logically consistent in my opinion, to say that gravity is spacetime curvature caused by mass/energy......mass causes spacetime to curve....voila! we have gravity.

Let's sum it up with that famous quotation of John Wheeler:
"Spacetime tells matter how to move; matter tells spacetime how to curve"
 
Anyone following this thread, and needing evidence for the claim of this being driven by an agenda, should go back to the very beginning, and note the insincerity that literally drips from the questions asked that have all been answered.

The reply below by one of our reputable members who appears to have given up on his antics sums it up quite admirably........

Again this all comes down to your assuming that astronomers don't know what they are doing. That there are all these things that they haven't considered. Believe me, they know what type of things will produce gravitational lensing and more importantly, how that gravitational lensing will appear. So when they look at the gravitational lensing of a galaxy they know what it should look like if all the mass was contained in the visible disk and what it would look like if most of the mass were spread out into a volume surrounding the disk. They see the second instance. It's not just that galaxies gravitationally lens light, it is the pattern in which the light is bent.

So far all your "suggestions" are on the order of asking a professional mechanic working on a car that won't start if he checked if there was gas in the tank (Silly, because one of the first things any mechanic would do is insure the fuel was reaching the engine), or worse yet, if he checked the air in the tires.

In essence and with the obvious intention of an argument against mainstream cosmology [without any evidence] this thread should at least be moved to the fringe and Alternative section.
 
Paddoboy, your arguments are full of reasoning based on words like logical and reasonable. Not so much direct evidence.

Length contraction must be true because we have observed time dilation? That is not an objective proof of length contraction. It supports the underlying theory but does not raise the conclusion to the status of proven.

Only one more thing, the results of the GP-B experiment only proved that a gyroscope would be affected by the motion of the earth, as predicted by GR. It did not prove how that occurs.., only that it does. AND this does not have anything to do with what my personal opinion(s) on the subject of the relationship between mass, graviation and spacetime are. It is only intended, to maintain a clear distinction between what is known to be and what is believed to be.., between what is known to be real and what is believed to be real, as a function of logical conclusions of theory.
 
Paddoboy, your arguments are full of reasoning based on words like logical and reasonable. Not so much direct evidence.

Length contraction must be true because we have observed time dilation? That is not an objective proof of length contraction. It supports the underlying theory but does not raise the conclusion to the status of proven.

No, at this time, we do not have the technical ability to measure length contraction.

So what are you saying?

We have direct evidence of time dilation, and two FoR's still measure "c"as "c".

So we ignore reasonable consensus and logic?

Only one more thing, the results of the GP-B experiment only proved that a gyroscope would be affected by the motion of the earth, as predicted by GR. It did not prove how that occurs.., only that it does.

Did I say anything different?
 
We certainly do not know the how and why of gravity, but just as certainly, we do know that gravity exhibits its presence when spacetime warps/curves in the presence of mass/energy.
Like all scientific models, the object is to describe what we see, and the question of reality remains open.

The above warping/curving, as well as the "Lense Thirring" effect were measured by GP-B, and aligned with the predictions of GR.
http://einstein.stanford.edu/highlights/status1.html
 
Did I say anything different?

The following sounds like it.

Secondly spacetime, is real and as I have mentioned, has been measured with GP-B.

Measuring how gyroscopes are affected by the earth's motion in space, consistent with GR prediction, has been proven. How the proven effect(s) emerge from the curvature of spacetime, remains an underlying theoretical model.

IOW proving a theoretical prediction, proves the predicted phenomena, and supports the accuracy of the underlying theory, but it does not raise the theory to the status of proven reality. We have not as yet, any direct observation of spacetime, as anything more than a geometric description of gravitation.
 
The following sounds like it.
.



One of us is confused.
I was referring to your reply thus.....
"Only one more thing, the results of the GP-B experiment only proved that a gyroscope would be affected by the motion of the earth, as predicted by GR. It did not prove how that occurs.., only that it does."

Correct, we do not know how or why gravity exhibits itself when spacetime is curved by matter/energy.
But that does not detract from the reality of spacetime, being real and as measured with GP-B, nor does it detract from the reality of matter/energy which causes spacetime to warp/curve.
 
Measuring how gyroscopes are affected by the earth's motion in space, consistent with GR prediction, has been proven. How the proven effect(s) emerge from the curvature of spacetime, remains an underlying theoretical model.

IOW proving a theoretical prediction, proves the predicted phenomena, and supports the accuracy of the underlying theory, but it does not raise the theory to the status of proven reality. We have not as yet, any direct observation of spacetime, as anything more than a geometric description of gravitation.


I think you are being unecessarilly pedantic.
We also know according to scientific methodology that no scientific theory is proven, but common sense and logic again, tells us that as scientific theories continue to match observations over time, they do become more and more certain.
Abiogenesis, Evolution, SR, GR, who in their right mind, would argue against any of those.

The many facets of evidence that supports the fact that gravity exhibits itself when spacetime deforms in the presence of mass, also in my opinion support those same entities as being real....
http://www.preposterousuniverse.com/blog/2013/10/18/is-time-real/
 
One of us is confused.
I was referring to your reply thus.....
"Only one more thing, the results of the GP-B experiment only proved that a gyroscope would be affected by the motion of the earth, as predicted by GR. It did not prove how that occurs.., only that it does."

Correct, we do not know how or why gravity exhibits itself when spacetime is curved by matter/energy.
But that does not detract from the reality of spacetime, being real and as measured with GP-B, nor does it detract from the reality of matter/energy which causes spacetime to warp/curve.

The point paddoboy is that the spacetime you refer to as real, remains the domain of theory. Spacetime is the geometry of GR that leads to predictions, some of which have been confirmed by the GP-B experiment.., how the gyroscopes were affected.., but the underlying theory remains theory. Spacetime is real as a geometry used to describe gravitation, it remains a theoretical abstraction when treated as a thing of substance. That does not make it unreal, it just means that even though thinking of spacetime as real, may follow from some logical consensus, it has not been observed directly. The gyroscope data from the GP-B experiemnt indirectly supports your conclusion, but does not raise it to the staus of independently observed reality.
 
. Spacetime is real as a geometry used to describe gravitation, it remains a theoretical abstraction when treated as a thing of substance. That does not make it unreal, it just means that even though thinking of spacetime as real, may follow from some logical consensus, it has not been observed directly. The gyroscope data from the GP-B experiemnt indirectly supports your conclusion, but does not raise it to the staus of independently observed reality.


I personally do not believe something needs to be observed to label it real.
But as with time itself, [which I think is real] the position is debatable.
 
I think you are being unecessarilly pedantic.
We also know according to scientific methodology that no scientific theory is proven, but common sense and logic again, tells us that as scientific theories continue to match observations over time, they do become more and more certain.
Abiogenesis, Evolution, SR, GR, who in their right mind, would argue against any of those.

The many facets of evidence that supports the fact that gravity exhibits itself when spacetime deforms in the presence of mass, also in my opinion support those same entities as being real....
http://www.preposterousuniverse.com/blog/2013/10/18/is-time-real/

You continue to make the same mistake. Common sense and logic are not objective or direct evidence. I am not arguing that SR, GR or even QM are wrong, only that they remain theory. A clear understanding of the difference between what has been objectively proven by direct evidence and what remains an underlying theory is important to the process of advancing our understanding of what is real. Once we begin to think of things which are only supported by common sense and logic as real, without direct evidence we limit our abitlity to move forward, by turning theory into a limit.
 
Disagree or not OnlyMe, its been a change to debate with you, someth
You continue to make the same mistake. Common sense and logic are not objective or direct evidence. I am not arguing that SR, GR or even QM are wrong, only that they remain theory. A clear understanding of the difference between what has been objectively proven by direct evidence and what remains an underlying theory is important to the process of advancing our understanding of what is real. Once we begin to think of things which are only supported by common sense and logic as real, without direct evidence we limit our abitlity to move forward, by turning theory into a limit.


I don't believe I am making any mistake...Firstly common sense and logic are dictated by continuous observations....secondly the theories I mentioned although technically remaining theories [which is what I have said] have all gained so much in certainty, that in many cases they are presented as fact by the scientific community.
This is where logic and common sense come into play.
 
Well, Rajesh the Riddler and OnlyMe the Philosophical Penguin! Do you actually enjoy being cast as comic foils for Einstein's electrodynamic duo comprising paddoboy & origin?:confused:

THE JOKER
 
Well, Rajesh the Riddler and OnlyMe the Philosophical Penguin! Do you actually enjoy being cast as comic foils for Einstein's electrodynamic duo comprising paddoboy & origin?:confused:

THE JOKER


If you refute Einstein and SR and GR, then submit what evidence you have to support your model, and get it properly peer reviewed.
Or are you going to cry foul along with the other cosnpiracy nutters?
 
Folzoni,

You just interrupted a small bang...The trigger was already there, the reverse countdown had started and just when it was about to blast...you initiated the Emergency Shut Down sequence.

On the topic,

I would say, there is a great deal of difference between mathematics and physical reality. Maths is so exhaustive that it can cover almost the entire spectra of physical reality, but maths is beyond that. I personally feel that space time is an abstract mathematical derivation, which fits into the physical observations correctly as on date, but it cannot be stated that space time is as real as what we can perceive or even visualize.

We have GP-B experiment which one gentleman is advocating very hard to give a notion of certainty and realism to space time curvature. Even though his own understanding about this experiment stands corrected just yesterday in this forum.

[No disrespect to the guys who conducted this experiment]. But does the experiment and subsequent analysis prove the reality or certainty of spacetime curvature ? This is an open question even today.

For example a patient can develop fever of certain nature, the cause can be TB, dengue, ebola, cold, gastric infection...anything. We put a thermometer and measure the temperature and lo behold...it is Ebola !!.....

On the other aspect, lets not get into semantics or linguistic jugglery..

Physics is very clear, it is Cause and effect.....We can say for sure that effect cannot precede the cause..

So I go back to the original statements with some improvement

1. Mass causes distortion in the space time curvature, and that is gravity.
2. Mass causes Gravity which in turn causes distortion in the spacetime curvature.
3. Space time curvature = Gravity (Synonym)

If third one is true, first two are useless...kind of fooling around with the words, but if third one is not true then only 1 or 2 may be correct. But the beauty is 2 will take us closer to Newton and 1 is of course Einstein.

Some one quoted in this thread below famous line..

Quote...
Let's sum it up with that famous quotation of John Wheeler:
"Spacetime tells matter how to move; matter tells spacetime how to curve"

....Unquote.

This statement has no value for Physics or maths. This appears a very profound statement like many other but answers nothing. [no disrespect to John Wheeler..]

Although I do not feel apologetic about my behavior in last couple of posts, wherein I got a bit personal with Paddoboy and Origin..still I feel I should not have lost my cool. But when I was talking about a small bang in the opening of this post, I was referring to the same temper loose kind of situation created by this gentleman for some other member.
 
Dear Rajesh,

Thank you for your very instructive reply. It indicates that I cannot help your immediate predicament since I categorically reject GR since it requires SR for its support in calculating the perihelion shift of Mercury - though I can see that you seem to be coming towards that viewpoint anyway. Hence when one is stuck in a halfway house, one is easily the prey of latter-day Thuggi - irrespective of whether they wear superhero costumes or not.

As for John Wheeler's comment, it expresses GR very cleverly - and as you say "has NO value for physics or maths." But poor Wheeler's antics are about as useful as that of Lonely Planet's Wheeler when he visited the Trobriand Islands off New Guinea. All the girls there - of more Polynesian appearance than other New Guineans - wished to meet him, but only because his surname was 'Wheeler' = wila, merely the local name for the male member, and not the local member of the PNG parliament!

I look forward to you comments on threads that dismiss Einstein's SR too!

FOLZONI
 
This statement has no value for Physics or maths. This appears a very profound statement like many other but answers nothing. [no disrespect to John Wheeler..]

Although I do not feel apologetic about my behavior in last couple of posts, wherein I got a bit personal with Paddoboy and Origin..still I feel I should not have lost my cool. But when I was talking about a small bang in the opening of this post, I was referring to the same temper loose kind of situation created by this gentleman for some other member.



What ever has value or no value in physics, is not determined by you, nor will it ever be.
It is determined by your peers and the tried and tested peer review system in science.

What you "think", what you "propose"with regards to cosmology, or what any other alternative hypothesis pusher proposes, is neither here nor there, in the greater scheme of things.
These science forums [particularly this one] is open to any Tom, Dick or Harry, and any pseudoscientific nonsense and quackery and the ratbags that push such ideas.
It in no where [something the rest of us can be thankful for] effects how real science progresses, and advances.

All the rest of us and mainstream logical thinking can do, is be thankful that such rantings and ravings are confined to forums such as this, while the real stuff outside, progresses without too much hindrance, other then those two horrible variables of economics and politics.
 
Quote...
Let's sum it up with that famous quotation of John Wheeler:
"Spacetime tells matter how to move; matter tells spacetime how to curve"
....Unquote.
This statement has no value for Physics or maths. This appears a very profound statement like many other but answers nothing. [no disrespect to John Wheeler..]
.



This statement actually has plenty of value for both physics and maths, and is quite profound, in summing up in a few words, how our Universe/spacetime/gravity operates.
Only those blinded by agendas would fail to see that.
Instead of deriding these scientific giants of the present and past, you need to do some thinking, stop misconstruing, and out right lying, and actually check out how and why these well supported, near certain theories have come about, and why they are so well supported after peer review.
 
It indicates that I cannot help your immediate predicament since I categorically reject GR since it requires SR for its support in calculating the perihelion shift of Mercury -

It's pretty simple. All you need to do, is come up with something, anything, that refutes SR/GR and/or the BB.
Continually waxing lyrical about what you think, has no bearing what-so-ever on the scientific world in general.
And that we can all be thankful for.
 
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