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hippy4christ
Skeptic Friend
193 Posts |
 Posted - 08/11/2004 : 15:24:38
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Hello,
I have a hard time believing in the whole "curved space" thing. Simply put, space is nothingness, how can it be curved? There is no "it" to curve.
I am currently reading a book called "The Universe and Dr. Einstein." Here is an excerpt: "The distinction between Newton's and Einstein's ideas about gravitation has sometimes been illustrated by picturing a little boy playing marbles in a city lot. The ground is very uneven, ridged with bumps and hollows. An observer in an office ten stories above the street would not be able to see these irregularities in the ground. Noticing that the marbles appear to avoid some sections of the ground and move toward other sections, he might assume that a "force" is operating which repels the marbles from certain spots and attracts them toward others. But another observer on the ground would instantly perceive that the path of the barbles is simply governed by the curvature of the field."
The problem that I have with this is that marbles are being acted upon by a physical substance, whereas space is not a physical substance. It was said that Einstein had a problem with Newton's idea of gravitation, which is that all matter exerts a 'force' - with no medium neccessary - upon all other matter. But saying that matter curves the space around it still says the same thing: matter exerts a 'force' of some kind that bends the space around it. Moreover, in this instance, the 'force' is being exerted upon nothingness! Is there any better evidence of space distortion?
Hippy
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Faith is believing what you are told, whether it's by a priest or a scientist. A person's scientific beliefs are ones based on personal observation and experimentation.
Lists of Logical Fallacies |
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welshdean
Skeptic Friend
United Kingdom
172 Posts |
Posted - 08/11/2004 : 16:05:31 [Permalink]
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Hippy,
I've never read that book, try 'The universe in a nutshell' by Hawkin. http://www.amazon.com/exec/obidos/tg/detail/-/055380202X/002-2553825-8124037?v=glance
It is critically acclaimed, very easy to read and is a definitive account of how we understand the universe today!
edited for my grandma |
"Frazier is so ugly he should donate his face to the US Bureau of Wild Life."
"I am America. I am the part you won't recognize, but get used to me. Black, confident, cocky. My name, not yours. My religion, not yours. My goals, my own. Get used to me."
"Service to others is the rent you pay for your room here on earth."
---- Muhammad Ali
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| Edited by - welshdean on 08/11/2004 16:27:48 |
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BigPapaSmurf
SFN Die Hard
3192 Posts |
Posted - 08/12/2004 : 12:42:48 [Permalink]
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Space is not nothing first of all, it is filled with particles and radiation. What you are thinking of is 'void' and such a condition has never been proven to exist.
Dont think of space as an object which bends think of it as a sheet of thin rubber with weighted balls all over it. When a ball (representing light or matter) is rolled across the sheet it 'curves' towords the nearest depression and if it has enough speed it will leave that depression and go on till it reaches another depression. The black hole makes a very large depression and very few things have enough speed to break free. The rubber sheet can be flipped on end and you will get the same results because the only 'down' in space is into a gravity well.
The moon for example is going just fast enough to slowly pull away from the earth. At 1.5 inches a year it goes farther out and as it goes farther the 'curve' in space that the earth makes will affect it less and less. It will eventually be thrown free from earths grip and who knows what it will smash into. (the sun most likely)
If however the moon was closer to the planet the atmospheric drag would slow down the moon enough where it would crash into the planet (again) |
"...things I have neither seen nor experienced nor heard tell of from anybody else; things, what is more, that do not in fact exist and could not ever exist at all. So my readers must not believe a word I say." -Lucian on his book True History
"...They accept such things on faith alone, without any evidence. So if a fraudulent and cunning person who knows how to take advantage of a situation comes among them, he can make himself rich in a short time." -Lucian critical of early Christians c.166 AD From his book, De Morte Peregrini |
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Dave W.
Info Junkie
USA
26022 Posts |
Posted - 08/12/2004 : 17:11:18 [Permalink]
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The rubber-sheet image is one of a two-dimensional "space" (the sheet itself) being distorted by masses upon it. In such a "flatland" world, the inhabitants would presumably only know those two dimensions, and so the distortions in the sheet would appear to be a force of some sort or another.
Analogously, in three dimensions, the distortions caused by mass "bend" space into yet another dimension (actually, masses bend the four-dimensional "space-time" into a fifth dimension), but since we're three-D creatures, it's hard as hell to visualize the situation completely. But the mathematics works out quite well - until you hit the pesky infinities inside a black hole. M-Theory, with eleven dimensions (!) in the math, may eliminate those infinities, if it can ever gel. |
- Dave W. (Private Msg, EMail)
Evidently, I rock!
Why not question something for a change?
Visit Dave's Psoriasis Info, too. |
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hippy4christ
Skeptic Friend
193 Posts |
Posted - 08/12/2004 : 19:15:35 [Permalink]
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Smurf:
The problem that I have with your analogy is that you are treating space like it is matter, specifically, a sheet of rubber. You said not to think of space as an object that bends and then went on to compare space to an object that bends. Are you equating space with particles and radiation? Is radiation the "ether" of the new science? I can see that particles and radiation travel through space, and if you took all particles and radiation out of the space than that area would be void of anything. But whether anything resides in a space or not, it's still space. Do you claim that a void would be immune to all forces, gravitational or otherwise?
Hippy |
Faith is believing what you are told, whether it's by a priest or a scientist. A person's scientific beliefs are ones based on personal observation and experimentation.
Lists of Logical Fallacies |
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Dave W.
Info Junkie
USA
26022 Posts |
Posted - 08/12/2004 : 20:01:47 [Permalink]
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Hippy, I wasn't as clear in my previous post as I should have been.
Einstein's General Relativity is a method of thinking about the universe which best matches what we actually see. Whether or not the force we perceive as gravity actually "bends" space-time is less relevant than the fact that General Relativity makes successful predictions about natural phenomena.
Nobody's ever seen gravity. The only thing we can measure about this force is its effects on the objects around us. For all we know, "gravity" is actually made by bazillions of little faeries pushing on things.
The important thing is that the actions of these hypothetical faeries is predictable. Every time we do thus-and-such, the faeries do so-and-so in response. That's one of the things which makes a scientific theory a success: being able to predict the natural world, whatever the ultimate underlying cause.
So the rubber sheet deal, the marbles in a sand lot, even the idea of "bending" space-time: they're all just methods through which physicists, astronomers, cosmologists and others have come to grips with the math which underlies the theory. And they're all easier to cope with than the equations themselves. They are simplifications for the general-public's consumption, whereas the real experts in these fields actually run numbers through equations to do their work.
Again: analogies of gravity and space-time on the one hand, and sandlots or rubber sheets on the other, don't imply any more similarities between the two things than the topologies involved. We can't look in from "outside" space-time to see if gravity actually bends it. That's just the easiest way to envision what the mathematics and the experiments tell us. |
- Dave W. (Private Msg, EMail)
Evidently, I rock!
Why not question something for a change?
Visit Dave's Psoriasis Info, too. |
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BigPapaSmurf
SFN Die Hard
3192 Posts |
Posted - 08/13/2004 : 05:39:16 [Permalink]
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Yes the bending and curves are only mechanisims which are used to help explain what is terribly complicated. You cannot remove the radiation from space. I made no claim that gravity would not work in space without material/radiation, just tried to explain that space is not empty.
Curve is only to help visualise the effects of gravity on light and mass, dont take analogies so seriously. Life is not 'exactly' like a box of chocolates, its just a metaphor.
The radiation I speak of is the cosmic backgroung radiation, which is the residual heat from the big bang, decaying black holes and such.
It is difficult since our definitions of void are different,
for me
Space is space, Void is a lack thereof. In my mind space cannot be void. |
"...things I have neither seen nor experienced nor heard tell of from anybody else; things, what is more, that do not in fact exist and could not ever exist at all. So my readers must not believe a word I say." -Lucian on his book True History
"...They accept such things on faith alone, without any evidence. So if a fraudulent and cunning person who knows how to take advantage of a situation comes among them, he can make himself rich in a short time." -Lucian critical of early Christians c.166 AD From his book, De Morte Peregrini |
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Ricky
SFN Die Hard
USA
4907 Posts |
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BigPapaSmurf
SFN Die Hard
3192 Posts |
Posted - 08/13/2004 : 07:07:48 [Permalink]
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ok to rephrase,
IF: There was a complete lack of material and radiation (a true vacuum)in between the earth and the moon gravity would still be in effect as normal.
If there was 0 material anywhere, of course there would be a lack of gravity. |
"...things I have neither seen nor experienced nor heard tell of from anybody else; things, what is more, that do not in fact exist and could not ever exist at all. So my readers must not believe a word I say." -Lucian on his book True History
"...They accept such things on faith alone, without any evidence. So if a fraudulent and cunning person who knows how to take advantage of a situation comes among them, he can make himself rich in a short time." -Lucian critical of early Christians c.166 AD From his book, De Morte Peregrini |
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Ricky
SFN Die Hard
USA
4907 Posts |
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Ricky
SFN Die Hard
USA
4907 Posts |
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hippy4christ
Skeptic Friend
193 Posts |
Posted - 08/13/2004 : 15:14:32 [Permalink]
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quote:
Whether or not the force we percieve as gravity actually bends space-time is less relevant than the fact that General Relativity makes successful predictions about natural phenomena.
I had a feeling you were going to say something like that. As I've read books on Relativity, the authors have often said that we can't really know what something is, we just percieve it as thus-and-so. Then they go on to talk like our perceptions are reality.
That being the case, if you're only using "space distortion" as a description, then why do you think that space will actually change it's properties under gravitational forces as are found in black holes? Why is the Big Bang a barrier to knowledge if you're not claiming that space actually will fold in on itself and change matter into something unrecognizable?
You say that the Theory correctly predicts one set of natural phenomena (the bending of light). Are you then going to say that it must be right in predicting another set of natural phenomenoa (space folding in on itself)? Just what is it that actually makes the Big Bang a barrier to science and logic?
Hippy |
Faith is believing what you are told, whether it's by a priest or a scientist. A person's scientific beliefs are ones based on personal observation and experimentation.
Lists of Logical Fallacies |
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astropin
SFN Regular
USA
970 Posts |
Posted - 08/13/2004 : 21:11:47 [Permalink]
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| My understanding is that the Big Bang IS the beginning of our space-time, thus we can only theorize about what happened prior to the B.B. itself. All of the laws of science were set in motion as a result of the B.B. Some Physicists theorize that there may be a near infinite number of other universes, each with their own unique natural laws which were set in motion by their respective Big Bangs. |
I would rather face a cold reality than delude myself with comforting fantasies.
You are free to believe what you want to believe and I am free to ridicule you for it.
Atheism:
The result of an unbiased and rational search for the truth.
Infinitus est numerus stultorum |
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hippy4christ
Skeptic Friend
193 Posts |
Posted - 08/14/2004 : 13:56:39 [Permalink]
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| Astropin: What evidence is there for this theory? |
Faith is believing what you are told, whether it's by a priest or a scientist. A person's scientific beliefs are ones based on personal observation and experimentation.
Lists of Logical Fallacies |
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Ricky
SFN Die Hard
USA
4907 Posts |
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astropin
SFN Regular
USA
970 Posts |
Posted - 08/14/2004 : 21:44:23 [Permalink]
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quote:
Originally posted by hippy4christ
Astropin: What evidence is there for this theory?
If you are referring to the "many universes" theory then I am not personally aware of any evidence to support it.
If you are referring the Big Bang that created our universe then there are stacks of hard evidence. Scientific observations and experiments tell us approximately when the Big Bang occurred, how much matter was created, and what will eventually happen to it in the far off future.
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I would rather face a cold reality than delude myself with comforting fantasies.
You are free to believe what you want to believe and I am free to ridicule you for it.
Atheism:
The result of an unbiased and rational search for the truth.
Infinitus est numerus stultorum |
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