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 HagbardCeline
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 You mix the right amount of bowling ball and trampoline then, BAM!!! Gravity... Pretty fuzzy math . 
#15498591 - 12/11/11 06:15 AM (1 year, 5 months ago) |
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I've never liked that analogy to describe how the bending of space-time by an appropriately massive object is the easy way to explain the manifestation of gravity. Maybe it's the dimensionality of it, but mentally, I always approach the idea the same way. I think about the ball causing the trampoline to sag under its weight, dislike that visualization because the force is only applied in one dimension, and then try to reconcile that by imagining an infinite number of trampolines acting on the bowling ball in all directions simultaneously.
Ugh...
I really don't like it.
It's because you are trying to imagine a scenario to understand how gravity is created by an object by explaining how you would see that ball cause the trampoline to sag - a scenario that is itself an effect of gravity.
No.
Wouldn't it be easier to imagine an inflated balloon that's underwater? Minus the tendency to rise of course.
Is it accurate to think of gravity like displacement in a fluid? The force of the fluid wanting to reoccupy that space is akin to gravity, the more massive an object is the more space it displaces, therefore increasing the effect of gravity?
But then, neutron stars and black holes are relatively small yet incredibly massive. I'm not sure how to resolve this analogy with density, but I'm pretty effing sleepy right now.
We haven't observed the force carrier for gravity, can space exert a force?
This may be simple but its never been something that I've tried to think about and had an "aha!" moment about.
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HagbardCeline
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 Re: You mix the right amount of bowling ball and trampoline then, BAM!!! Gravity... Pretty fuzzy math . [Re: HagbardCeline]
#15498605 - 12/11/11 06:24 AM (1 year, 5 months ago) |
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But now I realize this doesn't help explain how an object's gravity could exert an attractive force beyond the event horizon of my balloon bubble.
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 Seuss
Error: divide byzero
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Re: You mix the right amount of bowling ball and trampoline then, BAM!!! Gravity... Pretty fuzzy math . [Re: HagbardCeline]
#15498682 - 12/11/11 07:40 AM (1 year, 5 months ago) |
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> I've never liked that analogy to describe how ...
An analogy is not meant to be a perfect representation of how something works. An analogy is a simplification of a complex system, using something that most people are familiar with, to understand what the complex system is doing. If you really want to understand the complex system, then understand the mathematics behind it. Once the math makes sense, then the system makes sense (for the most part), and analogies are no longer needed.
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HagbardCeline
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Re: You mix the right amount of bowling ball and trampoline then, BAM!!! Gravity... Pretty fuzzy math . [Re: Seuss]
#15501663 - 12/11/11 10:05 PM (1 year, 5 months ago) |
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I can certainly appreciate that. My unwillingness to learn the necessary math has been a limitation to understanding other subjects to the level I would like as well. In those instances though it was quite clear to me that my mathematical ignorance was the limiting factor.
I can't recall thinking that in regard to the emergence of gravity. Not that I didn't recognize the value in understanding the math and the proficiency it would enable, but its a seemingly basic idea that is fundamental to so much, I expect that it should make sense to me regardless. From your understanding, or anyone who thinks they've got this one by the horns, do you believe mathematically challenged status is the most likely reason for my difficulty? What specifically should I endeavor to understand about math that will help alleviate my ignorance.
The main issue I believe is my inability to fully understand what about the interaction between space-time and mass begets gravity. Does anything about what I wrote above have a bearing on reality? How is it wrong? Is there a clear consensus on the process in question?
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 DieCommie
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Re: You mix the right amount of bowling ball and trampoline then, BAM!!! Gravity... Pretty fuzzy math . [Re: HagbardCeline]
#15501968 - 12/11/11 11:08 PM (1 year, 5 months ago) |
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I wouldn't expect it to make intuitive sense, particularly if you don't know the math. Intuition usually comes from familiarity and sufficient exploration of the subject. Since general relativity is counter to what we normally experience we cannot draw upon our life experience to guide our intuition.
Quote:
The main issue I believe is my inability to fully understand what about the interaction between space-time and mass begets gravity.
I bet you have heard this before... But here is how I conceptualize it without math. Space-time is a non-euclidean four dimensional space. It can be hard to define what a 'straight' line is in a non-euclidean space, for obvious reasons. So instead we consider the shortest path. The shortest path or straight line in such an exotic space is called a geodesic. Here we can use our intuition. We know that a body in motion will stay in motion and we know that it travels along a 'straight line'. But we know that the space the object moves in is non-euclidean so its 'straight line' is defined as being the 'shortest path' or geodesic. This shortest path that an object naturally travels along do to inertia appears to us, with a visual 2D/3D perspective, to be a curved path, a straight path or no path at all (standing still) depending on how we look.
So we can start with a space that is euclidean (flat) where shortest paths happen to be straight lines. In this space any object would either stay still, or move straight with constant momentum. Now we can introduce a piece of mass/energy to this space and change the straight lines around. Now some of them are curved outward, and some curve in on themselves - but they are all still the shortest path and objects still follow them naturally.
The math for this involves Einstein's field equations. These are equations which relate different configurations of mass/energy to different space-times. The way mass/energy profiles and space-time is written mathematically is simply with a large set of numbers (known as tensors). These tensors describe the behavior of the space-time at a point. They describe certain values at a point, as well as how values change at a point. So a particular mass/energy profile (knows as a momentum-energy-stress tensor) which describes the distribution of mass/energy entails a particular configuration of space-time (known as a metric tensor). With the metric tensor in hand you know the configuration of space/time. Now you can do a little calculus on it (differential geometry, calculus of variations) to find the shortest path (geodesic) or other interesting quantities.
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FNFAL
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Re: You mix the right amount of bowling ball and trampoline then, BAM!!! Gravity... Pretty fuzzy math . [Re: DieCommie]
#15503141 - 12/12/11 03:55 AM (1 year, 5 months ago) |
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Quote:
The math for this involves Einstein's field equations. These are equations which relate different configurations of mass/energy to different space-times. The way mass/energy profiles and space-time is written mathematically is simply with a large set of numbers (known as tensors). These tensors describe the behavior of the space-time at a point. They describe certain values at a point, as well as how values change at a point. So a particular mass/energy profile (knows as a momentum-energy-stress tensor) which describes the distribution of mass/energy entails a particular configuration of space-time (known as a metric tensor). With the metric tensor in hand you know the configuration of space/time. Now you can do a little calculus on it (differential geometry, calculus of variations) to find the shortest path (geodesic) or other interesting quantities.
WTF? If that's how you visualize it without math, I'd hate to see how it looks when you do use it. It's funny but I've done the exact thing Hagbard has. Trying to visualize the flat sheet with object in the middle bending space time, but trying to visualize it in three dimensions. But my puny little brain wont allow it to happen. It would only seem to work on one plane, like some sort of object between two vortices at a 180 from each other.
Does any of this make sense? I think my brain was built for the study of biology, not advanced physics. To me even if the math makes sense for some reason I need to visualize it.
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Simms
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Re: You mix the right amount of bowling ball and trampoline then, BAM!!! Gravity... Pretty fuzzy math . [Re: FNFAL]
#15515117 - 12/14/11 01:31 PM (1 year, 5 months ago) |
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Explaining gravity with object that curves space-time is like explaining gravity with gravity. What is the force that causes those curves? Why can't the object just float without affecting the curvature of space?
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Seuss
Error: divide byzero
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Re: You mix the right amount of bowling ball and trampoline then, BAM!!! Gravity... Pretty fuzzy math . [Re: Simms]
#15515991 - 12/14/11 04:59 PM (1 year, 5 months ago) |
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> Explaining gravity with object that curves space-time is like explaining gravity with gravity.
Not at all.
> What is the force that causes those curves?
It isn't a force, but the result of the effect of mass on space.
> Why can't the object just float without affecting the curvature of space?
Why don't pigs have wings?
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Simms
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Re: You mix the right amount of bowling ball and trampoline then, BAM!!! Gravity... Pretty fuzzy math . [Re: Seuss]
#15516588 - 12/14/11 06:54 PM (1 year, 5 months ago) |
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Quote:
Seuss said:
It isn't a force, but the result of the effect of mass on space.
How/in what way does mass affect space? It bends it? Well aren't we back to square one then here?
We do not quite know what is matter and how magnetism works on quantum level.
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HagbardCeline
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Re: You mix the right amount of bowling ball and trampoline then, BAM!!! Gravity... Pretty fuzzy math . [Re: Seuss]
#15517074 - 12/14/11 08:25 PM (1 year, 5 months ago) |
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So in thinking about this these past few days I've come to an idea that I would like some clarification on.
No one has yet addressed the question I originally posed about thinking of gravity like displacement. I was trying to evaluate it more thoroughly on my own when it occurred that in at least one important feature I could not imagine an alternative (of course one could exist.) If a mass can bend, distort, or curve space, then it can not be the empty void it appears. Something has to be interacting with that mass if it bends.
I know that I've read several different things about virtual particles and the revelation that a vacuum isn't the void it was thought to be. Though I've also seen the idea of all pervasive field or aether relegated to highest tier of crackpottery. Yet the much hyped Higgs mechanism requires an all pervasive field.
If the Higgs boson is the particle that imparts mass into matter and reliant on a seemingly invisible field, and gravity is the result of mass interacting with space through time which is home to this field, is the process of imparting mass and gravity one and the same? Wouldn't the Higgs boson be more of a signal flag then, letting the field know to impart mass. What happens if this field is blocked locally within a bubble, would everything just fly apart inside?
If you could cocoon a mass in mass-less particles, somehow immobilizing photons and encapsulating the object perhaps, what would occur? How would gravity interact with that object?
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Shins
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Re: You mix the right amount of bowling ball and trampoline then, BAM!!! Gravity... Pretty fuzzy math . [Re: HagbardCeline]
#15517172 - 12/14/11 08:47 PM (1 year, 5 months ago) |
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I too have proposed that gravity is spacetime (aether) displacement.
i got ridiculed out of the forum though because it would mean that a lot of quantum mechanics is bunk.
the double slit light experiment proves it IMO.
the photon displaces spacetime and creates concentric ripples, which alter its path and create the interference pattern.
scoff away.
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HagbardCeline
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Re: You mix the right amount of bowling ball and trampoline then, BAM!!! Gravity... Pretty fuzzy math . [Re: Shins]
#15519001 - 12/15/11 04:01 AM (1 year, 5 months ago) |
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Well, I am certainly no expert but there is issue I see with your explanation of the photon leaving a wake in its path. While I like the how aether sounds I can't get over the negative connotation I've developed over these years, so I'll stick with my idea about the field.
If there is an unseen field that plays a role in implying mass to particles, then photons should be practically invisible to the invisible field. Since no mass is allocated to the photons and it barely reacts to the field, then it shouldn't "displace spacetime and create concentric ripples" as they pass through. In other words it shouldn't leave a wake.
Also if your suggestion was correct, then space would be a one gigantic birds nest in the proverbial reel. For the non-fisherman a birds nest can be the most impossibly tangled ball of line caused from removing the slight tension on the spool you are supposed to keep and allowing the orderly wound line to become unsynchronized in its rotation in relation to the spool. If it is tangled more than a few windings deep, it can be quicker to cut the line and respool the reel than fight trying to untangle it. That's how a tangent is properly applied cateyes.
The reason I say this is because if the motion of a particle through the field leaves a distortion field, then what would all the massive bodies like stars do to space? The paths of all matter would be leaving their mark across every part of space they touched. Presumably these ripples would interact with themselves so you would end up with distortions from the echoes of distortions. Since we have a demonstrable understanding of these distortions with gravitational lensing, I feel certain that were the irregularities to persist then they would have been observed.
Or I could be wrong.
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Understanding is near, don't do anything stupid!
All be well!!!
Edited by HagbardCeline (12/15/11 04:07 AM)
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HagbardCeline
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Re: You mix the right amount of bowling ball and trampoline then, BAM!!! Gravity... Pretty fuzzy math . [Re: HagbardCeline]
#15911448 - 03/06/12 11:19 PM (1 year, 2 months ago) |
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If there is a Higgs field, the idea I was talking about seems to make more and more sense. The more massive an object is, the more gravity it has. It's actual size is of no importance.
If the field is what actually imparts the mass like what I reading about some time ago, then gravity is a by product of imparting mass.
If they were to end up finding the Higgs-boson (which from what I have read requires a complimentary field) then how is what I am saying wrong?
What I am saying is the force of the higgs field over time equals gravity. It is a bit akin to displacement then, though not exactly.
Please teach me how I am wrong.
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Wishing Well
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Re: You mix the right amount of bowling ball and trampoline then, BAM!!! Gravity... Pretty fuzzy math . [Re: HagbardCeline]
#15911762 - 03/07/12 12:24 AM (1 year, 2 months ago) |
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a field of trampolines, a stampede of animals, several bowling balls, and 10 unfortunate humans
the next big survival game show, I'd never watch it though
fuck tv
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