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Author Topic:   What is "the fabric" of space-time?
Phalanx
Member (Idle past 5712 days)
Posts: 31
From: Old Bridge, NJ, US
Joined: 10-12-2006


Message 181 of 327 (459831)
03-10-2008 4:38 AM
Reply to: Message 180 by johnfolton
03-10-2008 4:04 AM


Re: Energy from Nothing ???????
I have to say that I am having an extraordinarily difficult time deciphering what it is that you are attempting to say.
But, I think your question boils down to this: does the creation of space imply that there is a creation of energy?
I'm not too sure how exactly you decided that time is somewhere in the mix between energy and space. But, I think I can answer your question simply. There is no creation of space-time. There is an expansion of space-time.
The rest of your post is just gibberish to me. I'm not entirely sure how you worked Einstein, cosmic strings, string theory, and the idea of an ever-present God, but you did. Kudos to you for that, sir.
On an entirely different tangent - would it be possible for you to somehow edit your posts to make your thoughts more coherent. For the life of me, it seems that that post was just some stream of consciousness.
Disclaimer - I may be way off on multiple fronts here, so feel free to call me out. After all, it's 4:40am here, so I may not be entirely coherent myself.

And the Ignorant shall fall to the Squirrels - Chip 2:54

This message is a reply to:
 Message 180 by johnfolton, posted 03-10-2008 4:04 AM johnfolton has replied

Replies to this message:
 Message 183 by fallacycop, posted 03-10-2008 8:57 AM Phalanx has not replied
 Message 184 by ICANT, posted 03-10-2008 10:53 AM Phalanx has not replied
 Message 187 by johnfolton, posted 03-10-2008 1:56 PM Phalanx has not replied

  
Son Goku
Inactive Member


Message 182 of 327 (459844)
03-10-2008 8:52 AM
Reply to: Message 175 by Silent H
03-09-2008 6:07 PM


Re: A bit of history.
However, this appears to emphasize the issue I was talking about with cavediver. I've been asking about whether our current math is a model of the underlying reality, or just a useful tool.
Here is how I think about it and to support it I'm going to take concepts first developed by Wilson. In my mind this has nothing to do with Platonism vs. formalism, since that is a mathematical question and this is a physical question. Take a river. Currently we know that a river is "really" a collection of atoms, an entirely discrete collection of quantum mechanical objects. It isn't "really" a smooth continuum fluid. Does this matter?
The answer is no, the reason being because at large scales all the atomic degrees of freedom smear into large scale continuum modes which transport energy and momentum density. On our scale water "is" a continuum fluid. All other degrees of freedom disappear and it is inappropriate to think of water as a discretum. Hence the model is a correct conception of the phenomena.
Now what reason do we have to believe the more fully developed QFT is more than just a better tool?
Due to Kenneth Wilson's work we know that whatever the fundamental theory of reality, at low energy scales the degrees of freedom will "smear" together into a renormalizable quantum field theory. At our energy scales nature is a bunch of relativistic quantum fields. Think of it this way, just because a chair is made of atoms doesn't mean there is no chair. However nature is not a bunch of particle diagrams, a lá Feynman, at this scale.
With regards to curved spacetime, you have asked is spacetime really curved. Well here is my opinion. First of all, at these energies I can take out a watch and ruler and measure distances and times between events. These events are recorded as real numbers; hence I can smoothly map spacetime points on to real numbers. That is one of the first conditions of being a manifold. Next I check with my friend to see the values of his measurements. Turns out my results can be expressed smoothly as a function of his results. That's basically all we need, spacetime is a manifold. From purely physical considerations I have deduced spacetime is a manifold on these energy scales. What else do I know? Well I can tell exactly how far away my friends are with my ruler. That is I can put a number to it, rather than just being able to say they are "near". So spacetime has more than just topological structure, it has a metric structure.
I can send a satellite into near Earth orbit to measure distances around the Earth with respect to me. Turns out the distance is given by a function. I check with my friends, with their own satellites, how they record the distance function. Their distance function can be related to mine in a certain way, making this function a tensor. Finally derivatives of this function, called curvature, correspond to gravitational stress the earth's ocean feels. Making these curvatures have a physical effect. So in what sense, at these scales, is spacetime not a curved manifold?
Basically, can I say an apple is really 1 apple or is 1 just an accurate tool? Well at this scale, the scale we live at, there is 1 apple and I think that is true regardless of the quantum mechanics of the apples' atoms. Similarly matter is a quantum field at the compton scale and spacetime is a curved manifold regardless of what is going on at deeper scales.

This message is a reply to:
 Message 175 by Silent H, posted 03-09-2008 6:07 PM Silent H has replied

Replies to this message:
 Message 188 by Silent H, posted 03-11-2008 6:48 PM Son Goku has replied

  
fallacycop
Member (Idle past 5520 days)
Posts: 692
From: Fortaleza-CE Brazil
Joined: 02-18-2006


Message 183 of 327 (459845)
03-10-2008 8:57 AM
Reply to: Message 181 by Phalanx
03-10-2008 4:38 AM


Re: Energy from Nothing ???????
On an entirely different tangent - would it be possible for you to somehow edit your posts to make your thoughts more coherent. For the life of me, it seems that that post was just some stream of consciousness.
Only coherent minds can produce coherent thoughts.

This message is a reply to:
 Message 181 by Phalanx, posted 03-10-2008 4:38 AM Phalanx has not replied

  
ICANT
Member
Posts: 6769
From: SSC
Joined: 03-12-2007
Member Rating: 1.5


Message 184 of 327 (459861)
03-10-2008 10:53 AM
Reply to: Message 181 by Phalanx
03-10-2008 4:38 AM


Re: Space-time
Hi Phalanx,
Phalanx writes:
There is no creation of space-time. There is an expansion of space-time.
For something to expand it has to exist.
If Space-time was not created, where did it come from?
God Bless,

"John 5:39 (KJS) Search the scriptures; for in them ye think ye have eternal life: and they are they which testify of me."

This message is a reply to:
 Message 181 by Phalanx, posted 03-10-2008 4:38 AM Phalanx has not replied

Replies to this message:
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New Cat's Eye
Inactive Member


Message 185 of 327 (459865)
03-10-2008 11:35 AM
Reply to: Message 184 by ICANT
03-10-2008 10:53 AM


Re: Space-time
Wow, I've been away from awhile and you are still asking this nonsense question:
If Space-time was not created, where did it come from?
From? It has existed for all of time, it can't come from....
What is this, like, the 100th time you've told this?

This message is a reply to:
 Message 184 by ICANT, posted 03-10-2008 10:53 AM ICANT has not replied

  
fallacycop
Member (Idle past 5520 days)
Posts: 692
From: Fortaleza-CE Brazil
Joined: 02-18-2006


Message 186 of 327 (459871)
03-10-2008 12:17 PM
Reply to: Message 184 by ICANT
03-10-2008 10:53 AM


Re: Space-time
If Space-time was not created, where did it come from?
Will you knock-it-out?
We already answered this question a thousand times in the other thread. We don't need you bogging that one too. Can't you come up with something new to ask?

This message is a reply to:
 Message 184 by ICANT, posted 03-10-2008 10:53 AM ICANT has not replied

  
johnfolton 
Suspended Member (Idle past 5591 days)
Posts: 2024
Joined: 12-04-2005


Message 187 of 327 (459882)
03-10-2008 1:56 PM
Reply to: Message 181 by Phalanx
03-10-2008 4:38 AM


Re: Mass-Energy and Time created from Nothing !!!!!!!
Albert Einstein himself talking about space coming into existence and the scientists fronted by Stephen Hawkings theorizing that the entire universe is tied up with these tubular cosmic strings!
When space is coming into existence are tubular cosmic strings being created thats resisting the expansion. You have dark energy being proposed by NASA in respect to the driving of the expansion but is dark energy (God)? in respect to the expansion being observed is a force greater than nothing loosening tubular cosmic strings (bands of energy) so that yet more mass-energy is being created as space is expanding as Einstein proposed.
It might be that nothingness is really nothing but that nothing when expanded by an energy greater than nothing that tubular strings of cosmic energy are being created. Like in the expansion does it not look like energy is just popping into existence? If so then in the beginning before and at t=0 no energy or time existed meaning that all things were created from nothing by dark energy (God true light of true light), etc...
Just looking at it all from the point of nothingness and cosmic tubular strings like say proposed by the the dual teams of scientists from the University of Sussex and Imperial College London proposing that the entire universe is tied up with cosmic strings
and that all particles are made up from these cosmic strings.
Without dark energy (God) would these gravity like forces created by the expansion not pull the the entire universe including time and energy back into a state of nothingness t=0 & e=0? How is the earth itself not suspended on nothing does not time itself believed to go backwards to t=0 and forwards from t=0 where the mass-energy of the earth exists in a dimension going backwards and increasing forward in time.
Is the mass-energy of the earth not being increased thru this expansion of nothing we call time going forward from t=0, etc... It appears not only energy but time has been and is still being created from nothing e=0 & t=0, but t is this not being adjusted for the visible universe mathematically by the expansion rate of space by NASA by something they are calling dark energy responsible? It does appear that dark energy/God is responsible for the creation not just energy but time from nothing, etc...
Did Einstein not theorize that empty space if expanded would increase in energy? like something from nothing, and not dilute existing energy. That this is just a property of space itself ?
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Could The Universe Be Tied Up With Cosmic String?
ScienceDaily (Jan. 21, 2008) ”
A team of physicists and astronomers from the University of Sussex and Imperial College London have uncovered hints that there may be cosmic strings - lines of pure mass-energy - stretching across the entire Universe.
The Microwave Sky. The detailed, all-sky picture of the infant universe from three years of WMAP data. The image reveals 13.7 billion year old temperature fluctuations (shown as color differences) that correspond to the seeds that grew to become the galaxies. (Credit: NASA/WMAP Science Team)
http://www.sciencedaily.com/...ases/2008/01/080120182315.htm
Albert Einstein was the first person to realize that empty space is not the same as nothingness. Space has amazing properties, many of which are just beginning to be understood. The first property of space that Einstein discovered is that it is possible for more space to come into existence. One version of Einstein's gravity theory makes a second prediction: "empty space" can possess its own energy. This energy would not be diluted as space expands, because it is a property of space itself; as more space came into existence, more of this energy-of-space would come into existence as well.
Page Not Found | Science Mission Directorate
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This message is a reply to:
 Message 181 by Phalanx, posted 03-10-2008 4:38 AM Phalanx has not replied

  
Silent H
Member (Idle past 5819 days)
Posts: 7405
From: satellite of love
Joined: 12-11-2002


Message 188 of 327 (459978)
03-11-2008 6:48 PM
Reply to: Message 182 by Son Goku
03-10-2008 8:52 AM


Re: A bit of history.
Oh, that was a very nice progressive argument.
Let me see where I am getting things wrong by bringing up another set of measurements. I can record heights of people. I can also record time. If plotted for any person they will tend to show a curved structure. Does that mean that time is shaping people's height? Or maybe that height effects time?
That things can be plotted, and the plot useful, does not mean there is a direct interaction, rather only a solid correlation. It may be eminently useful to produce calculations based on a space-time model, but couldn't that simply be a correlation, rather than a causative structure?
See it starts getting iffy to my mind when we speak of mass and time interacting, given that they are simply measurable quantities. We can speak of how we measure their relation, but their direct connection?
If you reply to this post, as an addition can you unpack what a tensor is? That is a bit of ignorance on my part. I've heard the term and seen some discussions which were too vague for me to understand.

h
"Civilized men are more discourteous than savages because they know they can be impolite without having their skulls split, as a general thing." - Robert E. Howard

This message is a reply to:
 Message 182 by Son Goku, posted 03-10-2008 8:52 AM Son Goku has replied

Replies to this message:
 Message 189 by Son Goku, posted 03-13-2008 7:49 AM Silent H has replied

  
Son Goku
Inactive Member


Message 189 of 327 (460179)
03-13-2008 7:49 AM
Reply to: Message 188 by Silent H
03-11-2008 6:48 PM


Re: A bit of history.
First of all, to understand this post, you should know that it isn’t only mass that is supposed to cause spacetime curvature, but angular momentum, stress, even heat.
Let me see where I am getting things wrong by bringing up another set of measurements. I can record heights of people. I can also record time. If plotted for any person they will tend to show a curved structure. Does that mean that time is shaping people's height? Or maybe that height effects time?
That things can be plotted, and the plot useful, does not mean there is a direct interaction, rather only a solid correlation. It may be eminently useful to produce calculations based on a space-time model, but couldn't that simply be a correlation, rather than a causative structure?
You have recorded height as a function of time. The direct reading of the mathematics is that at "this time" you will have "this height" and that is exactly what you have. There is not a dynamic coupling between height and time, such as there is (vaguely speaking) between mass and time in GR. A function indicates some sort of dependence between quantities. For an actual coupling, where the quantities affect each other, you would expect a dynamical equation of motion, which would give functional solutions, something you have not recorded in your example. In fact you can easily see there is no coupling because in your example the time axis never changes, its values are simply mapped to height values. I appreciate though that “reading” maths is a skill that takes time to develop.
See it starts getting iffy to my mind when we speak of mass and time interacting, given that they are simply measurable quantities. We can speak of how we measure their relation, but their direct connection?
I understand what you mean. However we have literally observed that objects near a large mass start having their clocks run slow, frequencies drop, in fact every physical process “slows down”. The effect is stronger nearer the mass and with increased density the effect becomes stronger. You also have to bear in mind that this isn’t an entirely philosophical issue. I can put statistical strength behind the assertion “mass affects time”. That is, with repeated measurement of various independent quantities the likelihood of the assertion being correct increases. It is now very, very likely to be correct.
Also, to expand on my last post, there are in fact satellites in near earth orbit that use synchronised clocks and standard “rulers” to measure the spatial and temporal curvature near the earth. Even if you ignore for a moment the claim that mass causes spacetime curvature, we actually have observational evidence that spacetime is curved from these satellites. Which means we have empirical evidence that spacetime can be a dynamical entity and not simply a static observable. However, from the observations we then see that this curvature matches exactly (within observational error) the predictions of General Relativity of the effects of the Earth’s mass on spacetime. It even matches the predictions concerning the effects of the Earth’s angular momentum on spacetime.
Also, unlike your example above, General Relativity is an entire framework which produces several consequences of the coupling of spacetime and mass. An example is neutron star orbit decay. All this stuff was predicted in advance as a consequence of the effects of this mass/spacetime interaction. It was not a case of us coming upon some kind of correlation between them and then assuming causation.
Another thing to bear in mind is that mathematically speaking, if the equivalence principle is true and special relativity holds, mass has to affect spacetime. You can not avoid that conclusion mathematically.
So, on a statistical, logical and observational front we have very good reason to conclude that mass causes spacetime to curve.
If you reply to this post, as an addition can you unpack what a tensor is? That is a bit of ignorance on my part. I've heard the term and seen some discussions which were too vague for me to understand.
A Tensor, physically, is a measurable quantity that has a definitive rule describing how it is viewed in one particular coordinate system (read reference frame, roughly speaking) compared to another. A simple example would be electromagnetic field strength. It takes six numbers to record electromagnetic field strength and those numbers measured in one frame can be related to the numbers measured in another frame. In fact you could see it as confirmation of special relativity. According to special relativity it is a tensor and observations confirm the fact that is a tensor.

This message is a reply to:
 Message 188 by Silent H, posted 03-11-2008 6:48 PM Silent H has replied

Replies to this message:
 Message 190 by Silent H, posted 03-14-2008 3:26 PM Son Goku has replied

  
Silent H
Member (Idle past 5819 days)
Posts: 7405
From: satellite of love
Joined: 12-11-2002


Message 190 of 327 (460381)
03-14-2008 3:26 PM
Reply to: Message 189 by Son Goku
03-13-2008 7:49 AM


Re: A bit of history.
So, on a statistical, logical and observational front we have very good reason to conclude that mass causes spacetime to curve.
Well what the hell kind of reasons are those????
Heheheh. Your last few replies to me have been very useful for me and I'm quite thankful.
I apologize for the height-age example. I came up with it off the top of my head (a correlation involving time) but you adequately pointed out where it was not the same type of measurement-connection under discussion. I didn't reply immediately because I've been trying to think of a better example, but perhaps in the glare of your explanation of various independent quantities bearing out the same relationship I can't seem to find anything worthy.
I can't remember who told me about the GPS satellite time differential issue first, but that always struck me as a very strong indicator GR concepts were on the money. Still the maverick in me wants to make sure I'm not jumping on an apparent causative connection. Maybe something else (some other explanatory concept) ties them all together, though with similar mathematical results. I guess one could analogize this to the way Newton's laws are a subset of GR's results, which has a completely different explanatory concept).
I hope that makes sense.
One remaining question for now. Why is it with the success of GR in the realm of physics, that gravity is still discussed (and even taught) as a force between objects? I understand that the classical equations and concepts are easy, but shouldn't science be making a stronger push to flip the conceptual understanding to the correct model... from the beginning?

h
"Civilized men are more discourteous than savages because they know they can be impolite without having their skulls split, as a general thing." - Robert E. Howard

This message is a reply to:
 Message 189 by Son Goku, posted 03-13-2008 7:49 AM Son Goku has replied

Replies to this message:
 Message 193 by Son Goku, posted 03-17-2008 9:11 AM Silent H has replied

  
Silent H
Member (Idle past 5819 days)
Posts: 7405
From: satellite of love
Joined: 12-11-2002


Message 191 of 327 (460525)
03-16-2008 1:20 AM


gravity and disappearing matter, (esp for cavediver, but all welcome)
Up thread I gave a hypothetical of some mass appearing and asking about resulting gravitational effects. Cavediver pointed out that this cannot happen. I mentioned that I had seen a similar hypothetical made by a physicist (though it was disappearing matter), and cavediver said that too cannot happen.
I'm not disputing anything said by cavediver, but I did find the video where I saw the hypothetical. It is from Brian Greene's Elegant Universe and the hypothetical starts about 3 minutes into the vid clip.
Perhaps someone can tell me what I got wrong, or if he was wrong.
Also to cavediver, can you finish explaining the sphere example related to time and motion. I think I got it wrong (after seeing an example by Chiro elsewhere). I'm still trying to get down (in a way I can explain to others) how/why objects at rest will be drawn into motion by a curvature of time toward another body.
Why does a body continue accelerating vs simply moving to a constant speed? Also, both bodies in a 2 body system actually start into motion toward each other, right? This raises the question of why there is a difference based on unequal mass as to which body is shifted more out of its original position, if it is simply an issue of following the curvature of time? Does each body's imposed space-time curve effect the other body separately, rather than creating a singular curve between them? Or does the time curve effect different size masses differently?
Also, if it is the curving of space-time which causes the motion of A toward B, why does it create momentum as if a force were acting on A, rather than both simply moving closer as if space were disappearing between the objects (sort of a reverse of space increasing between them due to cosmic expansion)?
Anyone can answer of course.

h
"Civilized men are more discourteous than savages because they know they can be impolite without having their skulls split, as a general thing." - Robert E. Howard

Replies to this message:
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cavediver
Member (Idle past 3643 days)
Posts: 4129
From: UK
Joined: 06-16-2005


Message 192 of 327 (460529)
03-16-2008 6:18 AM
Reply to: Message 191 by Silent H
03-16-2008 1:20 AM


Re: gravity and disappearing matter, (esp for cavediver, but all welcome)
Perhaps someone can tell me what I got wrong, or if he was wrong.
Neither, really. He's just being fast and loose It gets the point across, but it is an impossible situation. It's just MUCH more simple than trying to describe a realistic situation, e.g. using an extended charge through the Earth to blow it into two halves, which continue to orbit the original center. This changes the gravitational quadrupole moment, and gravitational waves are emitted which will affect the moon, not instantly, but at the retarded time as the gravitational disturbance propegates at the speed of light...
Will get back to the rest later

This message is a reply to:
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Son Goku
Inactive Member


Message 193 of 327 (460614)
03-17-2008 9:11 AM
Reply to: Message 190 by Silent H
03-14-2008 3:26 PM


Re: A bit of history.
Silent H writes:
I can't remember who told me about the GPS satellite time differential issue first, but that always struck me as a very strong indicator GR concepts were on the money.
The GPS satellite wasn't designed to directly test GR, so if you're looking for better experiments check out the PSR B1913+16 pulsar binary system experiments. There is also gavity probe a and more recently gravity probe b.
Also, one thing I cannot stess enough to people, is that we have directly measured that spacetime is curved. Even if somebody disagrees with GR's mechanism of mass causing that curvature, we know that the curvature exists. However I think the best way to see what GR proposes is to understand the Minkowski spacetime structure of special relativity. Then understand how an accelerated observer views the path of a light ray and finally combine this understanding with the equivalence principle and the realisation that there are no forces on you in free-fall. It soon becomes fairly clear that mass causes the curvature of spacetime.
Basically an accelerated observer will see that light has a curved path. By the equivalence principle, light also has this path in a homogenous gravitational field created by a given mass. However the light is in free fall and has no forces on it and also from SR, the light simply follows null geodesics in spacetimes*. So the only way the curved path can occur is if the null geodesics themselves have become altered, which means the spacetime now has a dfferent shape due to the mass.**
Silent H writes:
One remaining question for now. Why is it with the success of GR in the realm of physics, that gravity is still discussed (and even taught) as a force between objects? I understand that the classical equations and concepts are easy, but shouldn't science be making a stronger push to flip the conceptual understanding to the correct model... from the beginning?
Several reasons. Mainly it's far too difficult to put in context for a child, since GR makes no sense without SR, pedagogically speaking.
*Null geodesics are a kind of straight line in spacetime.
**Remember, in this example, the only thing I've put in the spacetime is the mass, so there is nothing else to "pin the mechanism on".
Edited by Son Goku, : Slight addition.

This message is a reply to:
 Message 190 by Silent H, posted 03-14-2008 3:26 PM Silent H has replied

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johnfolton 
Suspended Member (Idle past 5591 days)
Posts: 2024
Joined: 12-04-2005


Message 194 of 327 (460642)
03-17-2008 3:40 PM
Reply to: Message 193 by Son Goku
03-17-2008 9:11 AM


Re: A bit of history.
However the light is in free fall and has no forces on it and also from SR, the light simply follows null geodesics in spacetimes*. So the only way the curved path can occur is if the null geodesics themselves have become altered, which means the spacetime now has a dfferent shape due to the mass.**
If you sit in a spinning chair and put your hands out you will slow but bring your hands inward and you can feel your speed increasing.
Is not it supporting Newtonian gravity that something and not just nothing (the curvature of space) responsible?
If Einstein was totally right this should not be happening like if light is only just following the curvature of space.
The spinning skater priciple seems more supporting Newtonian gravity that a force other than nothing is speeding up or slowing down the skaters spin.
It seems there is a bit of truth to both Einstein and Newtonian gravity. Is string theory not trying to explain the fabric of space time to bridge the nothing part the(curvature of spacetime) with something such as (that mass energy cosmic tubular strings are curving space thru time)? a real force reaching outward responsible for creating this curvature within the fabric of space thru time)?
P.S. That something and not just nothing is bending light and not just nothing (curvature of space) is responsible when a skater spins faster by bringing ones arms inward, etc ... !!!!!!!
Edited by johnfolton, : No reason given.
Edited by johnfolton, : No reason given.

This message is a reply to:
 Message 193 by Son Goku, posted 03-17-2008 9:11 AM Son Goku has not replied

Replies to this message:
 Message 195 by Rahvin, posted 03-17-2008 4:05 PM johnfolton has replied

  
Rahvin
Member
Posts: 4032
Joined: 07-01-2005
Member Rating: 9.2


Message 195 of 327 (460644)
03-17-2008 4:05 PM
Reply to: Message 194 by johnfolton
03-17-2008 3:40 PM


Re: A bit of history.
If you sit in a spinning chair and put your hands out you will slow but bring your hands inward and you can feel your speed increasing.
Is not it supporting Newtonian gravity that something and not just nothing (the curvature of space) responsible?
This has nothing whatsoever to do with gravity. It's simple mechanics. It has absolutely nothing to do with gravity or spacetime.
If Einstein was totally right this should not be happening like if light is only just follow the curvature of space.
The spinning skater priciple just seems more supporting Newtonian gravity that a force other than nothing is speeding up or slowing down the skaters spin.
A spinning skater has nothing to do with relativity, Newtonian gravity, or bending light. It's nothing more than simple mechanics. The skater doesn't actually speed up, per se - he retains the same actual speed, but his rotations per second increase. If his hands fully extended are traveling at x m/s, they will still be traveling at x m/s when he retracts them. It's just that it takes less distance traveled to rotate fully if the circumference is smaller.
Two wheels of different sizes traveling at the same speed will have different rotational rates for the same reason.
P.S. It seems there is a bit of truth to both Einstein and Newton gravity. Is string theory about trying to explain the fabric of space time to bridge nothing (curvature of spacetime) and something(that mass energy cosmic strings are pulling inward) a real force part creating this curvature part within the fabric of space thru time)?
That something and not just nothing is bending light and not just nothing (curvature of space) is responsible when skater spins faster by bringing ones arms inward, etc ... !!!!!!!
Both Einstein and Newton were "right," it's just that Newtonian gravity is accurate at certain scales and not at others. It's still what we use for plotting space probe trajectories, because it's highly accurate at that scale.
I don't think you have a firm grasp of basic mechanics, Newtonian physics, or relativity. Nothing in your post is relevant to the topic.

This message is a reply to:
 Message 194 by johnfolton, posted 03-17-2008 3:40 PM johnfolton has replied

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