Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: Outcast on 10/02/2020 16:51:27
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Einstein could discover no mechanism for gravity's influence across space...
So he theorized that matter warps space...and provided no mechanism whereby matter does this.
I don't see this as a good answer.
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It's the best we had, until the discovery of gravity waves. Still no evidence of a particle, but you are welcome to join the search.
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It's the best we had, until the discovery of gravity waves. Still no evidence of a particle, but you are welcome to join the search.
I thought Einstein predicted gravitational waves...just thought we would never detect them.
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I thought Einstein predicted gravitational waves...just thought we would never detect them.
An argument can always be made that that which can't be detected doesn't exist.
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It's the best we had, until the discovery of gravity waves. Still no evidence of a particle, but you are welcome to join the search.
I never thought "the laws of physics permit it" was a strong argument. The laws of physics permit square turds...that's not a compelling reason for me to squander my brief flicker of a lifespan searching for square azzholes...LOL
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I thought Einstein predicted gravitational waves...just thought we would never detect them.
An argument can always be made that that which can't be detected doesn't exist.
An argument can be made for that which can't be detected, even in principle, doesn't exist
But you can't make an argument that "because we are too clumsy to find it, it doesn't exist"
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And now we have detected the waves. It's still an odd force that doesn't seem to have a complement, but it seems I'm not alone in postulating negative mass particles, so there's still hope.
In fact the laws of physics do not allow square turds, as any physicist can tell you.
How you squander your life is entirely your concern, but criticising a dead genius for his honesty certainly wouldn't appeal to me as a pastime.
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An argument can always be made that that which can't be detected doesn't exist.
We have detected gravitational waves many times over by now, so that's not an issue.
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How you squander your life is entirely your concern, but criticising a dead genius for his honesty certainly wouldn't appeal to me as a pastime.
Einstein's theories criticized a multitude of dead geniuses that came before him...I'm sure a few were honest...
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The laws of physics permit square turds...that's not a compelling reason for me to squander my brief flicker of a lifespan searching for square azzholes...LOL
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Einstein could discover no mechanism for gravity's influence across space...
So he theorized that matter warps space...and provided no mechanism whereby matter does this.
I don't see this as a good answer.
The problem is science fanzies who hold einstein up as some sort of prophet. Newton was not alone in his time either and it did spring from nowhere. The incandessant vacuum tungsten lightbulb was invented simultaneously, just on the back of others. einstein was however not bad at science.
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In fact Einstein stands out as possibly the only experimentally proven prophet. Others (including Newton) have explained existing observations or had the temerity to question Aristotle's logic, but relativity theory has accurately predicted a whole bunch of stuff, from gravitational lensing to the hydrogen bomb, that had never been seen or even sought previously.
Love the wombat poo. Yes, folks, there's nothing too weird or trivial for this forum! Interestingly, though, whilst their turds are isosymmetric with cubes (evolution?) , they do not (cannot) have sharp edges (biophysics).
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Einstein could discover no mechanism for gravity's influence across space...
So he theorized that matter warps space...and provided no mechanism whereby matter does this.
I don't see this as a good answer.
This comment is worth 10 points on the "Crackpot Index":
"17. 10 points for arguing that while a current well-established theory predicts phenomena correctly, it doesn't explain "why" they occur, or fails to provide a "mechanism". "
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This comment is worth 10 points on the "Crackpot Index":"17. 10 points for arguing that while a current well-established theory predicts phenomena correctly, it doesn't explain "why" they occur, or fails to provide a "mechanism". "
Newton had a current well-established theory that predicted phenomena very accurately for a long time. Was Einstein a crackpot when he argued that wasn't enough?
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This comment is worth 10 points on the "Crackpot Index":"17. 10 points for arguing that while a current well-established theory predicts phenomena correctly, it doesn't explain "why" they occur, or fails to provide a "mechanism". "
Newton had a current well-established theory that predicted phenomena very accurately for a long time. Was Einstein a crackpot when he argued that wasn't enough?
The reason It "wasn't enough" was that there were already "chinks' showing up in Newton's Theories by the time Einstein began to formulate his theory. Einstein didn't start working on his theory because he didn't think Newton didn't provide a mechanism, but because issues had been arisen in Physics that needed answers. Newton's physics couldn't account for Mercury's extra precession, for example.
Einstein wasn't the first or only person to to address these issues, But he was the first one come up with a complete theory capable of dealing with them.
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Newtonian mechanics doesn't address "why" - or even "how", or provide a "mechanism". It does give adequately predictive formulae for the motion of mesoscopic objects but we still don't know why massive bodies attract each other, or, if you prefer, always warp spacetime in the same sense.
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we still don't know why massive bodies attract each other, or, if you prefer, always warp spacetime in the same sense
Is it a good starting off point to take it as axiomatic that the "natural" relationship between relative space measurements and time measurements is variable ?
Would that take us any further towards detecting the actual mechanism(s?) that caused changes in that variability?
To the OP I think it was probably in Einstein's character to kick the can down the road and continue running after it.
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The reason It "wasn't enough" was that there were already "chinks' showing up in Newton's Theories by the time Einstein began to formulate his theory.
Do you recognize any "chinks" in Einstein's theories?
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To the OP I think it was probably in Einstein's character to kick the can down the road and continue running after it.
I concur...he was still working on it on his deathbed.
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Einstein thought he recognised a few, but the experimental results seem to hold up so far.
It's all firmly grounded on the axioms that c is constant and all motion is relative. The first axiom derives from Maxwell who showed that there are no variables or unknowns in the propagation of electromagnetic radiation in vacuo, the second is supported by the absence of any universal reference frame that we can detect. So you go on to develop the fundamental equations of physics, discover that things aren't quite linear as v → c or g > 0, and carry out the experiments that, to nobody's surprise, yield the predicted result to an exceptional degree of accuracy.
If there are chinks in the theory, they will be revealed by experimental anomaly. No good evidence to date.
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Is it a good starting off point to take it as axiomatic that the "natural" relationship between relative space measurements and time measurements is variable ?
Not an axiom because not easily observed or self evident.
Would that take us any further towards detecting the actual mechanism(s?) that caused changes in that variability?
Considering that physicists accept it is observed and have based a lot of theories and experiments on the basis of it being true, I can’t see how it moves us any further towards an ‘actual mechanism’.
Currently the assumption is that any form of energy will result in a curvature of spacetime (note: not a bending of spacetime). Mass just happens to be one of the most concentrated forms of energy that we have, hence its affect is greater than most other forms.
When people talk about an ‘actual mechanism’ they are missing the point. GR provides the mechanism, the very fact that the spacetime dimensions are not ‘flat’ as we might expect is the mechanism and it is well described in the field equations. I think @Janus has described it elsewhere.
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When people talk about an ‘actual mechanism’ they are missing the point. GR provides the mechanism, the very fact that the spacetime dimensions are not ‘flat’ as we might expect is the mechanism and it is well described in the field equations. I think @Janus has described it elsewhere.
So not so much a mechanism as a basic condition ("flat space" is just a special case that applies when there are no local sources of gravity and the "natural" condition is just a function of the local distribution of energy)
But if we do not have a theory of Quantum Gravity does it not follow that there are mechanisms involved in spacetime curvature yet to be explained?
E.g. we don't know yet ,do we whether spacetime should be a continuous or a discrete model ,do we?
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The model can be continuous or discrete as you wish. It's easier to solve continuous equations, and until we discover a graviton with quantum properties, the continuum model will rule.
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The reason It "wasn't enough" was that there were already "chinks' showing up in Newton's Theories by the time Einstein began to formulate his theory.
Do you recognize any "chinks" in Einstein's theories?
To date, none have been found. Every time we perform a new test, the theory passes. How long this will continue, no one knows. we suspect that there is a better theory out there. For one thing GR doesn't "play well" with QM, and there are quite a few people out there trying to formulate a ways of joining them together. It might even be helpful if some experimental discrepancy could be found, as it might give us a hint of where to look.
and as @alancalverd has already pointed out, Newton didn't provide a mechanism either. And his theories were accepted and well-established for centuries. The point being that "does not provide a mechanism" is not a valid criticism of a theory.
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The point being that "does not provide a mechanism" is not a valid criticism of a theory.
I realize it's not a science reference, but it's the first line in describing the history of gravitational theory. The mechanisms have always been an integral part of the theories.
"History of gravitational theory
From Wikipedia, the free encyclopedia
In physics, theories of gravitation postulate mechanisms of interaction governing the movements of bodies with mass."
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To date, none have been found.
Many would argue that its inability to mesh with quantum mechanics is a "chink". Although relativity seems to be extremely accurate on large scales, it likely diverges from reality to some extent on certain extreme scales (like large amounts of mass crammed into tiny volumes, such as when stars collapse into black holes.)
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The mechanisms have always been an integral part of the theories.
Can you be specific about which mechanisms you are referring to in each case?
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The history of non-science is full of mechanisms, mostly involving incestuous gods in the form of animals. Scientists occasionally discover bits of mechanism but the equations we consider to be laws of physics are mathematical abstractions of what happens, not lists of the components of nature.
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The history of non-science is full of mechanisms, mostly involving incestuous gods in the form of animals. Scientists occasionally discover bits of mechanism but the equations we consider to be laws of physics are mathematical abstractions of what happens, not lists of the components of nature.
Here's one list of the main branches of physics.
1 Classical mechanics.
2 Thermodynamics and statistical mechanics.
3 Electromagnetism and electronics.
4 Relativistic mechanics.
5 Quantum mechanics.
6 Optics, and atomic, molecular, and optical physics.
7 Condensed matter physics.
8 High energy/particle physics and nuclear physics.
Four of the branches contain "mechanics" in the name. No gods, no animals, no incest.
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Can you be specific about which mechanisms you are referring to in each case?
The original question concerned a mechanism whereby matter warps space.
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Mechanics: mathematical modelling of functional systems. Prediction of system functions. Physics.
Mechanisms: description of how components fit together. Realisation of functional systems. Engineering.
Hence celestial mechanics predicts the sunrise and the trajectory of an asteroid, but whilst relativistic mechanics gives us the answer, we still haven't found a gravity exchange particle, let alone a testable mechanism for the creation of matter in the first place. That's where our forebears hypothesised the incestuous and bestial relationships of fairies, but it doesn't seem to have much predictive value or help us to fly around the world.
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In fact Einstein stands out as possibly the only experimentally proven prophet. Others (including Newton) have explained existing observations or had the temerity to question Aristotle's logic, but relativity theory has accurately predicted a whole bunch of stuff, from gravitational lensing to the hydrogen bomb, that had never been seen or even sought previously.
Love the wombat poo. Yes, folks, there's nothing too weird or trivial for this forum! Interestingly, though, whilst their turds are isosymmetric with cubes (evolution?) , they do not (cannot) have sharp edges (biophysics).
Isnt it a bit soon to say that ? How long before problems with newtons theory where uncovered ? Relativity is a part just like newtons stuff, yet it is held up as absolute. After all, Einstein really only created the Aether after denying it.
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After all, Einstein really only created the Aether after denying it.
That's just silly.
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Einstein could discover no mechanism for gravity's influence across space...
It was never the purpose of GR to do so. No scientist to date has ever discovered a mechanism for gravity.
So he theorized that matter warps space...
Warps spacetime as well as space, not just space.
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..and provided no mechanism whereby matter does this.
I don't see this as a good answer.
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That's okay. The rest of the physics community thinks so. :) Seriously though. Einstein knew that the presence of mass generates a gravitational field. That was demonstrated by Newton. What Einstein showed that not just mass by any kind of energy does also as does stress and momentum.
In any case its not true that Einstein theorized that matter warps space. It fell out the theory. Also matter is not always generate warped spacetime in all cases. E.g. the spacetime of a uniform gravitational field is not warped, its flat.
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I thought Einstein predicted gravitational waves...just thought we would never detect them.
That's true.
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An argument can always be made that that which can't be detected doesn't exist.
That's a bad argument since it can't be known what can and can't be detected unless by their nature they can't be detected. In that case we call them virtual like in virtual particle. But we did detected gravity waves.
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Einstein's theories criticized a multitude of dead geniuses that came before him...I'm sure a few were honest...
Not at all. Einstein's theories either explained that which was as of yet unexplained or provided a more precise description of what had already been explained.
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The reason It "wasn't enough" was that there were already "chinks' showing up in Newton's Theories by the time Einstein began to formulate his theory.
Do you recognize any "chinks" in Einstein's theories?
I myself don't.
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An argument can be made for that which can't be detected, even in principle, doesn't exist.
Utterly brilliant! Viral disease is caused by electron microscopes! Give the man a Nobel Prize.
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If we consider gravitation fields to actually be physical objects in the same way as magnetic fields are ,can we say that mass/energy distorts these fields?
If that was so it would put to bed the head scratching that goes on when people try to visualize space or spacetime being somehow physically curved when ,intuitively that just feels absurd.
I know that gravitational fields are very different from magnetic fields and it would be difficult /impossible to feel them in the same way because everything is subject to gravitational fields .( you can feel magnetic fields because the human body is less subject to that field than ,say a metallic object it might hold in the hand. )
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You can feel a gravitational field. Lead is much more susceptible to gravitation, and hydrogen much less so, than human tissue. You can also sense the absence of a gravitational field by jumping out of a plane.
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You can feel a gravitational field. Lead is much more susceptible to gravitation, and hydrogen much less so, than human tissue. You can also sense the absence of a gravitational field by jumping out of a plane
So it is perfectly acceptable to think of the field as a physical object that is subject to deformation? Is it a 3d +1 physical object?
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Not really. A gravitational field is a mathematical abstraction that predicts how bodies will move in the presence of one another, or how photons will behave in the vicinity of a massive body.
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So it is perfectly acceptable to think of the field as a physical object that is subject to deformation? Is it a 3d +1 physical object?
As Alan says the field is a mathematical abstraction. What you do is place a test mass (1kg) and measure the force vector acting on that mass, that vector is the field strength (unit gravitational force) at that point (you can do the same with a magnetic field, using a test magnet). In this case you create a map of of gravitational force values for a volume of space.
That’s all a field is. The value of it is that with gravity we can use a simple formula to calculate the field strength at any point between 2 masses, and hence the force between 2 masses.
When we say spacetime is curved we are saying we can use the maths of curved surfaces to describe the motion of a mass in a gravitational field.
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As Alan says the field is a mathematical abstraction. What you do is place a test mass (1kg) and measure the force vector acting on that mass, that vector is the field strength (unit gravitational force) at that point (you can do the same with a magnetic field, using a test magnet). In this case you create a map of of gravitational force values for a volume of space.
That’s all a field is. The value of it is that with gravity we can use a simple formula to calculate the field strength at any point between 2 masses, and hence the force between 2 masses.
Is that the famous Einstein Field Equation I have heard of?
(if it is I am glad to learn it is simple :) )
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Is that the famous Einstein Field Equation I have heard of?
(if it is I am glad to learn it is simple :) )
Whoops, you caught me there being nonspecific.
I should have said calculate approximate field strength. These are Newton’s equations, good enough to land men on the moon but not accurate enough to predict the precession of planets to very high accuracy. Like any more accurate calculation, Einstein’s field equations are somewhat more complex; don’t despair however, the basics of how they work is very easy to understand, it’s solving them that’s hard.
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You (the OP) are right to say that there is no mechanism for curving Spacetime. Worse than that, there is no way for the mass in the singularity of a black hole to govern the shape and size of its event horizon and gravity well without faster-than-light control signals - if the black hole accelerates, it would have to be dragged along by it's gravity well rather than moving its gravity well. However, the establishment now claims that Lorentz Ether Theory is just a different philosophical slant on the same theory, and LET does have a mechanism for all of this: there is a medium involved which slows the speed of light more at greater depth in gravity wells, and that medium is a dark extension of the visible matter that we see at the bottom of the well, and that dark extension is simply the result of each particle being spread out through the whole universe. So, it should be possible to translate that mechanism to the mathematical abstraction of Spacetime in some way, although it will need faster-than-light aspects to get that control from the singularity to things at higher altitude.
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Outcast, are you trolling us?