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Junior Member (Idle past 5349 days) Posts: 24 From: Chorley, Lancs, UK Joined: 

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Author  Topic: The accelerating expanding universe  
NoNukes Inactive Member

Alfred Maddenstein writes: How then you can explain that the millions of people who can read no maths are being so convinced of the validity of the Big Bang paradigm? They believe others who can check the math? They are convinced by descriptions of observations that confirm the theory? At present you have zero credibility. From you, rigorous proof is required


Alfred Maddenstein Member (Idle past 4188 days) Posts: 565 Joined:

Ultimately again all that boils down to a massive trust in the others better judgement and being impressed by the numerous repetitions of confidence in that judgement expressed by those others while suspending any own scrutiny.
I'll tell you a little story. I once knew this old Russian lady. I was in love with her niece and the two of them were living together at the time. Now the lady had no previous knowledge about the state of the modern cosmology. All she was aware of was that the universe was awfully big. That was all the science back in Soviet times had told her as the idea of the Big Bang was not particularly favoured by the Soviets. Also the lady was not religious due to the Soviet atheistic upbringing. Once I was waiting for my lover to come home in the company of that old dear and I was in a humorous mood so to pass the time I told the lady a bit more about how huge the universe was supposed to be and I told her that lately the science had discovered that all those trillions of galaxies with quadrillions of stars separated by all those humongous distances had an origin in time, originated from a single point and at that point of origin were all contained inside a point trillions of times smaller than anything she could possibly see even with her glasses on. And I told her that this tiny point containing the future universe was at that instant enveloped into nothing to be later blown up to all these immense proportions. When the lady heard me telling all that with a serious face, she became visibly confused. She could not decide whether I was raving or was simply pulling her leg. I kept reassuring her that neither was the case but that it all was the latest scientific knowledge and I told her that if she'd ask her niece her niece would confirm every word I'd said. That was what she did when the niece finally arrived. The niece reassured the lady that I was neither raving nor taking the piss and she confirmed that all this was exactly the latest scientific theory and that all that was exactly what the majority of astronomers believed. I could witness the conception of her growing trust at its very point of origin. I was after all a stranger to her and she knew me as a joker, as somebody highly antisocial and full of suspicious habits but the niece was something different, the niece was somebody close and reliable who was studying at the university and so on. I saw that her initial strong doubts based on her simple common sense started dissipating. Once the idea was confirmed to have originated from a trusted authority of science and not from such a wild and irresponsible type like myself, it lost most of its immediate absurdity for the lady Edited by Alfred Maddenstein, : Grammar


Oli Junior Member (Idle past 4615 days) Posts: 16 From: United Kingdom Joined: 
Hi there, this is my first post!
I have looked through the book by Alexander Franklin Mayer you referred to earlier. It can be found here:http://jaypritzker.org/pages/book.html Although I don’t claim to have followed all of the text, the main thrust of the argument seems to be that Einstein did not understand the geometric meaning of Minkowski spacetime as intrinsically four dimensional when he derived General Relativity, and by extension the big bang model doesn’t include time correctly. The author uses the big bang timeline to apply his point of view to the universe. He claims that, as special relativity means there is no absolute universal time (since observers moving at different speeds experience time differently relative to each other), there should be no universal time axis from which to construct the timeline. However, in the derivation of the FRW metric (as I understand it) we observe that the universe is isotropic and homogeneous on large scales. Then the galaxies or superclusters make up a ‘cosmological fluid’ filling the universe. The proper time for ‘Fundamental Observers’ at rest in this cosmological fluid can be used to define a universal time. Spacetime is sliced up into spacelike hypersurfaces, each labelled by a constant time coordinate, so that the worldlines of the fundamental observers are orthogonal to the surfaces. So although the big bang model does include a form of absolute time, this does not mean spacetime is not intrinsically fourdimensional. Oli


NoNukes Inactive Member 
Alfred Maddenstein writes: Ultimately again all that boils down to a massive trust in the others better judgement and being impressed by the numerous repetitions of confidence in that judgement expressed by those others while suspending any own scrutiny. It does not depend much on trust anymore. Countless physics students have learned to follow the math. There are plenty of tutorials on the subject that allow even more people to grasp the basics. Some people do simply accept things without being able to check they math, but even those people can look for indicators that reliably point to quackery. For example, I know where real science turns up first, and it is not in vanity published books or on web pages. In my experience, science promoted in that way is invariably ignorable. Extraordinary claims require extraordinary proof. Sorry, but that's the way it is.


cavediver Member (Idle past 3864 days) Posts: 4129 From: UK Joined:

He claims that, as special relativity means there is no absolute universal time (since observers moving at different speeds experience time differently relative to each other), there should be no universal time axis from which to construct the timeline. Yes, this is a common crank perspective  they have just about managed to understand the basics of SR and so are completely thrown by GR when it seems to contradict many of the "truths" they have learnt; and thus they conclude that GR, one of the most successfully tested theories known to science, must necessarily be wrong simply because of their own incomprehension. Don't you just love them
However, in the derivation of the FRW metric (as I understand it) we observe that the universe is isotropic and homogeneous on large scales. Then the galaxies or superclusters make up a ‘cosmological fluid’ filling the universe. The proper time for ‘Fundamental Observers’ at rest in this cosmological fluid can be used to define a universal time. Spacetime is sliced up into spacelike hypersurfaces, each labelled by a constant time coordinate, so that the worldlines of the fundamental observers are orthogonal to the surfaces. Exactly.


cavediver Member (Idle past 3864 days) Posts: 4129 From: UK Joined:

No, I am not confusing the Special and General relativity. I reckon that is a flaw if there a contradiction and inconsistency between the two. There is no inconsistency and no contradiction. SR simply describes the local (tangent space) physics, and GR describes the global physics. In other words, GR restricted to the local environment, reduces to SR. Expansion (and inflation) of the Universe is necessarily a global feature and thus SR is not applicable. Locally, the speed of light is never violated, and that is all that matters. Again, your incomprehension is simply your own  not that of the rest of us. Edited by cavediver, : No reason given.


Alfred Maddenstein Member (Idle past 4188 days) Posts: 565 Joined:

Oli, your reasoning shows that so far your mind only glanced past the concepts in the book. Nowhere the author claims that anything is fourdimensional as it sounds per your misrepresentation. His idea is different. It is based on the understanding that since there are three spatial dimensions and the motion in any of them is measured by and is convertible into time, the time dimension is orthogonal to each three of them and not to all the three at once and that the true geometry of time should be derived from such understanding necessarily and that such understanding stems from the original Minkowski.
You need to invest a bit more effort in following both the logic and mathematics in the book discarding preconceptions at the door. Could you elaborate on the cosmological fluid, fundamental observers, sliced hyperspheres and the rest as those notions sound to me rather vague and are straining my poor logic greatly.


Alfred Maddenstein Member (Idle past 4188 days) Posts: 565 Joined:

So far, Cavedriver, you have failed to demonstrate how is that fellow Mayer is a crank compared to yourself. His theory is based only on what is strictly observed while yours needs to resort to dark forces, black matters and holes and the rest of physical impossibilities like the inflation belonging to banking and not the natural science. And even with all the help of magic in your premises, your hypothesis does not fit the observations and the data found in all the satellite databases while his does fit everything very nicely and the links to all the databases that are provided in the book for everyone to check and compare show that clearly. So who is the crank here is moot indeed.


Oli Junior Member (Idle past 4615 days) Posts: 16 From: United Kingdom Joined:

Alfred,
Firstly, when you say: ...since there are three spatial dimensions and the motion in any of them is measured by and is convertible into time, the time dimension is orthogonal to each three of them... I believe you mean the same as the book which says: It is based on the understanding that since there are three spatial dimensions and the motion in any of them is measured by and is convertible into time, the time dimension is orthogonal to each three of them. This correctly implies that Minkowski’s spacetime is a four dimensional ‘combination’ of three space and one time dimension. Secondly, I apologise for using specialist language, not that I claim to be a specialist in any way. The ‘Fundamental Observers’ and hypersurfaces are just a way of defining a coordinate system in the universe. There are an infinite number of ways to do this, just as there are an infinite number of ways to specify a location on the Earth’s surface. For example, we could give the position of London by its longitude and latitude, by a number of miles and direction from Paris. Just as any of these methods is equally valid on Earth, we are free to choose any coordinate system to specify positions in space and time in General Relativity. The fundamental observers are then hypothetical ‘beings’ who are at rest with respect to all the ‘stuff’ in the universe: the ‘cosmological fluid’. To simplify the maths, the FRW spacetime is commonly expressed using the proper time of the Fundamental Observers as a time coordinate. I hope this clears things up, but I don’t find it easy to explain. Oli


Alfred Maddenstein Member (Idle past 4188 days) Posts: 565 Joined: 
Yes, Oli, I understand all that what I do not get is by what trick of mathematics from that notion of fundamental observers which per your description sounds like something perfectly arbitrary, relative, hypothetical and imaginary, the contention that there is a single timeline possessing a definite point of beginning called the Big Bang with a strict calendar of sequential events that is valid for the whole infinite process called the universe is derived? How anything that is supposed to possess a physical reality is extrapolated from those universal fluids and fundamental observers?
Also even if the author still uses the traditional notion of four dimensions just like Minkowski did before him, the intention is to show that such use is very approximate, poor, potentially misleading with that misleading potential fully realised in the whole corpus of modern cosmology and physics. One could use six dimensions just as well. Three spatial and three temporal. That would be better yet still not good enough so what the author really means is rather than dimensions, time vectors or directions should be used and since there are an infinity of possible directions in space with a corresponding directions in time which are strictly orthogonal to any of the spatial ones, time is possessing the same infinity of directions necessarily. From that its true curvature is derived with a precise gradient of its dilation that is ubiquitous, rotating timelines and so on. So far his logic is compelling until anybody has shown me otherwise using still better logic.


Son Goku Inactive Member

quote:Well the answer to that question is a whole graduate course on General Relativity. However let me try to give some answers. Okay, so we notice a few things: (a)The laws of physics don't really depend on position or velocity. (The insight of Newton) I'll just say a little bit more about (a). Newton's famous equations F=ma tells you that the force on a body, F, causes an acceleration, a (proportional to the mass). So objects will all react to the same force in the same way, even if they encounter it at different locations and at different speeds. Let's call objects which aren't accelerating (a=0) "inertial observers". Now Maxwell's equations predict:(b) For a given inertial frame, light has a constant speed that never changes. So by the spirit of Newton's insight this means that every inertial observer should see light moving at a constant speed. Unfortunately the transformations that Newtonian physics gives for moving between frames (which are based on our intuition), change the speed light, so that different inertial observers see the speed of light differently. Hence a prediction of Maxwell's equations seems to depend on velocity, unlike anything else in physics. Einstein didn't like this (neither did experiment), so he had the idea that perhaps the transformations to go from one observer to another should be altered from our intuition to new transformation laws which keep the speed of light the same. He wrote down these new transformation laws. The new transformation laws say that time will dilate and space contract as you move between observers (as you speed up or slow down). It seems odd, but it is the only way to keep the speed of light the same for all observers, so that the laws of physics don't depend on your velocity. Of course it leads to strange things, the same transformation laws imply that mass is related to energy, e.t.c. However these things have been confirmed. So if you live near a nuclear power station your house is "powered by" resolving a conflict between Maxwell's equations and Newton's insight. Soon after this, Minkowski realised that these new transformation laws are simply the transformation laws for a four dimensional world where time is an extra dimension and this four dimensional world is now called Minkowski space.This is Special Relativity. What about gravity? Einstein was initially having trouble working gravity into relativity, until he had a fundamental insight: the equivalence principle. A person who is falling feels no force. If you fell toward a planet with your eyes closed and the planet had no atmosphere, you would feel nothing (well except when you hit the ground). Since force is related to acceleration, observers who are falling are like those with no acceleration, a=0. Or to put it another way, falling observers are inertial observers. If you just put a planet in Minkowski space the trajectories of inertial observers do not bend towards the planet, so falling observers will not be inertial. To correctly model the scenario you need another spacetime, one whose inertial trajectories are falling trajectories. In fact you'll need a different spacetime for each arrangement of matter. "Falling" in these trajectories will then just be following an inertial path, something that requires no force. So gravity is not a force, just the result of following the contours of spacetime and the shape of spacetime depends on the matter present.This is General Relativity.


Alfred Maddenstein Member (Idle past 4188 days) Posts: 565 Joined:

Thank you, for your very reasonable exposition of General Relativity. Unfortunately I do not see how from anything either Einstein or yourself stated may follow anything that would require violating the necessity of the Copernican mediocrity principle being applied temporally. As it is the principle is spatially honoured by the contemporary cosmological model. Given the unity of space and time this situation strikes me as a contradiction.
All that you said about the free falling bodies constituting the inertial frames is correct. The universal flat calendar hardly follows from any of that. What it may imply philosophically in terms of motion is only that the speed of light is the speed of time itself. This is the speed of universal motion but in the same breath it is the measure of the universal rest. That is why the velocity of light is as constant as the now is unchanging while serving as the rest frame to the changes moving past it. Mass, energy, gravity and acceleration are all acting as the brakes on that speed. The differential of masses creates the all differential of relative velocities below that universal speed of time as well as the very opposition of motion to rest. In that sense motion is different bodies settling their mass differential. The differential is never settled once and for all so the motion is endless. That does not imply though any single linear direction of that motion while the very word expansion suggests an outward uniformity of it. Nor the possibility of space itself moving independently at supersuperluminal velocities follows from the strict unity of space, time and light being all but aspects of one and the same. What relativity suggests is that space, on the contrary, may not possibly overtake the light in that fashion. If it is understood that the speed of light is the speed of time at rest, it becomes abundantly clear that the space rushing ahead of light would imply the space going faster than time and that it must be forming loops around itself which is absurd and is not what is being observed.


subbie Member (Idle past 1476 days) Posts: 3509 Joined:

Unfortunately I do not see how from anything either Einstein or yourself stated may follow anything that would require violating the necessity of the Copernican mediocrity principle being applied temporally. This physics stuff is so far over my head that I really can't make much of anything anyone says about it. But I gotta say, this quoted portion just sounds like meaningless word salad. Can anyone confirm that for me? Or, in the alternative, if it does mean something, can it be translated into something resembling English? Ridicule is the only weapon which can be used against unintelligible propositions.  Thomas Jefferson We see monsters where science shows us windmills.  Phat It has always struck me as odd that fundies devote so much time and effort into trying to find a naturalistic explanation for their mythical flood, while looking for magical explanations for things that actually happened.  Dr. Adequate ...creationists have a great way to detect fraud and it doesn't take 8 or 40 years or even a scientific degree to spot the fraud'if it disagrees with the bible then it is wrong'....  archaeologist


crashfrog Member (Idle past 1688 days) Posts: 19762 From: Silver Spring, MD Joined: 
. But I gotta say, this quoted portion just sounds like meaningless word salad. Can anyone confirm that for me? Yes, this is complete and utter nonsense. It has all the semantic content of "colorless green ideas."


cavediver Member (Idle past 3864 days) Posts: 4129 From: UK Joined:

Or, in the alternative, if it does mean something, can it be translated into something resembling English? Much of Alfred's ramblings are confused and meaningless, but this does actually mean something The Copernican Mediocrity Principle is essentially the first version of what we now call the Cosmological Principle: there is nothing special about our spatial location in the Universe. Alfred, much like Hoyle many many years ago, feels that this should apply also to our temporal position, i.e. there is nothing special about our location in time. It is a perfectly acceptable and reasonable philosophical stance except that it is highly contradicted by observation and theory. Because Alfred feels that his philosophical position should hold more weight than the entire worldwide body of professional astronomers and comsologists, he believes that our observations have been misinterpreted and our theory of spacetime defective. However, Alfred's above post is quite correct in that nothing in SG's post suggests that General Relativity should give rise to a situation where there Copernican Principle does not apply in the time direction. The confusion arises because General Relativity is not a theory of the Universe  it is the mathematics that generates theories of spacetimes  a metatheory. When we use GR to construct the spacetime around a black hole, we see perfect time symmetry. We only see the lack of time symmetry when we ask GR to produce a theory for the spacetime of the Universe. Alfred doesn't like this. Tough



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