Why Can't the Universe be Contracting?
Science people, you are going to love to beat me up over this one. I am missing a big bit of information (or logic) about the expansion of the universe, and can't seem to find the answers online. I have been missing missing these pieces for quite some time now. If you could help me fill them in, I would appreciate it.
We are told, after Hubble observed some colored light through his telescope- that light from distant objects in the universe is red shifted. This tells us that the galaxies are all receding away from us. This is true in whatever direction you look. And the velocity of recession is proportional to the distance, with those on the fringe moving the fastest. It is therefore said that the Universe is expanding.
But my conjecture is that it is contracting. We are instead moving away from those galaxies, thus causing a red shift. It makes more sense, as we approach the centre of the universe, the gravitational pull gets stronger accelerating the rush. This explains the shifts and the difference in relative shifts between galaxies.
I also suggest (in case I need to invoke it later) that space contraction around galaxies may be happening. But I won't get into it unless it is needed.
I also wonder; is the inference that we are at the centre of the universe, as everything is red-shifted away from us? It sounds a bit geocentric doesn't it?
It may seem like I am playing semantics, but the when we consider we may have it all backwards, the very fate of the universe, as well as its origin story may be at stake.
Could you provide me with the evidence for the expansion please.
We are told, after Hubble observed some colored light through his telescope- that light from distant objects in the universe is red shifted. This tells us that the galaxies are all receding away from us. This is true in whatever direction you look. And the velocity of recession is proportional to the distance, with those on the fringe moving the fastest. It is therefore said that the Universe is expanding.
But my conjecture is that it is contracting. We are instead moving away from those galaxies, thus causing a red shift. It makes more sense, as we approach the centre of the universe, the gravitational pull gets stronger accelerating the rush. This explains the shifts and the difference in relative shifts between galaxies.
I also suggest (in case I need to invoke it later) that space contraction around galaxies may be happening. But I won't get into it unless it is needed.
I also wonder; is the inference that we are at the centre of the universe, as everything is red-shifted away from us? It sounds a bit geocentric doesn't it?
It may seem like I am playing semantics, but the when we consider we may have it all backwards, the very fate of the universe, as well as its origin story may be at stake.
Could you provide me with the evidence for the expansion please.
Comments (159)
It is my understanding that the evidence is, as you say, the red shift. It's not that everything is moving away from us, everything is moving away from everything. The analogy they use is the surface of a balloon. The universe isn't expanding, it's inflating. If my understanding is correct, the universe is not inflating in space, it is space itself that is inflating.
If it were contracting, there would be a blue shift.
We're reaching the limits of my knowledge. I don't understand what you mean when you say "contracting away from us." Galaxies are moving away from us no matter what direction we look in.
1. If they are moving away from us they are red shifted.
This also means
2. If we are moving away from them, they are red shifted (its relative [who is really moving?]). If it's us that's moving faster than them it could be because:
A: We could be moving away from them linearly (as we race faster than them toward the centre of the universe)
OR
B: We could both be contracting, which would also open the space between us, causing a red shift.
I am arguing A, and allowing that B might also be happening.
I don't think there is a center of the universe. If there is, and if we were moving toward it, we would be moving away from some galaxies and toward others. That's not what has been observed.
I'm not sure what you mean by "both contracting." If each individual galaxy were contracting into itself, depending on where we are in the Milky Way we would see some stars in a galaxy moving toward us and some moving away.
Hmmm. What I think we've observed is red shifted galaxies relative to us. It could be that those closest to the centre (we need a centre for a big bang or for a new convergence place) are moving faster than us toward the centre, just as those further from the centre are moving slower relative to us. It would make sense as gravity grows stronger - almost like a singularity toward the centre.
We haven't been studying the sky for long enough to observe actual movement of the galaxies relative to each other, but if we did, and it was non-directional, then shrinkage could account for it.
I take your point though that those on our 'left and right' could be moving at the same speed as us and convergence might blue shift them... unless they are also shrinking at a faster rate than the convergence rate (I thought I might need that card).
As I said before, we'll have to wait for someone who knows more than I to carry this on further.
Hey, I just thought of something. Maybe Australia is moving away from the United States. I've noticed that your posts seem a bit red shifted.
https://thephilosophyforum.com/discussion/comment/104721
Let me first state that I have of course no way of knowing whether the universe is really expanding or not. As it has been noted, the sole argument in favor of expansion is the color shift (red), and that is itself based on a theory that is accepted by everybody... except by me. But since I am, in academic terms, a nobody, don't let it deprive you of your sleep.
see also
https://philpapers.org/post/17834
Why would I think that? I prefer to think that great minds meet, don't you?
I am suspicious of theories rejected by the consensus of the scientific community. If you look, there are lots of people that say relativity and quantum mechanics are hoaxes. At the same time, I am sympathetic to the frustration that comes from not understanding the chain of inference that scientists follow on complex issues. It would be helpful if we could get someone on the line who knows the science well.
Your suspicion is shared by many. I find it reassuring that not any objection to the consensus is blindly accepted. I understand the need for Science to be conservative, and set the bar higher. At the same time, discussions of what seems to be an eternal truth should not be silenced. Your suggestion that only people who do not understand a theory do not agree with it is very condescending, and, I am convinced, wrong.
Science changes, and what was regarded as beyond doubt becomes obsolete. Let us not forget that. As Einstein once said to his audience during one of his lectures, yesterday you all believed in the ether.
In what way am I trying to silence you? It is not condescending of me to point out that your position may not be credible. What is your background? Why should we pay attention to your opinion on this matter? Profound new understandings of the nature of the universe don't generally, if ever, come from people outside the scientific community. It's reasonable to ask for high standards of justification if someone makes a claim like yours. It's also reasonable to ask someone with specific scientific experience in the area under discussion to give us their $0.02 worth.
why are you so hostile? If you think I am not credible, just ignore me.
edit: let us not hijack this thread.
The issues you bring up really require a new abstraction of the nature of perception and space. Instead of viewing space as "distance", one can totally disengage from this abstraction, and look upon space as "the ability to act upon" within a given duration. This, I believe, is what Bergson was working on, but it is so different from the way we are taught to perceive, it requires a total shift in the way we understand perception.
One way to begin this process of deliberation would be to try to merge the dream state with the awake state and declare each is exactly the same in regards to space and duration, that is solve the differences and similarities by treating them as one.
This approach requires tremendous dedication, and I may be too old to try it, but the only starting point that I know of is a total familiarity with Bergson and then take it from there.
BTW, there is an excellent chance you will not understand this but since you seem to be traveling in this direction, I decided to give it a try. It is only for the most dedicated, creative, and inquiring minds.
I do not share your enthusiasm for Bergson, even if I do feel much sympathy for his ideas. Einstein has opened the way of thinking about space in a non-Newtonian way (mathematicians were before even Einstein in their quest for non Euclidean geometries), and maybe we should keep looking in this direction, and not consider the results of the 20th century as immutable.
I confess that I find the fact that we can see across immense distances with a telescope as something that has not been fully analyzed in all its consequences.
The only way to understand nature is via direct observation and intuition based upon studying patterns. There is no shortcuts and requires an enormous amount of dedication (sorry, meditation or any other shortcuts fall far short). As I said, it requires a mind tremendously skilled in intuition and pattern recognition and thus takes a long time to acquire. Definitely not for everyone and only for the most dedicated. Bergson was too far ahead and his brilliant insights outside the envelope of understanding of almost everyone. Einstein's response to Bergson's critique was a good case in point.
I don't get it. I'm being polite. I'm being responsive to the OP. In a situation like this, since you are expressing a controversial opinion, I think it is reasonable to ask about your qualifications. How is that hostile? How am I a hijacker?
I am too old to interview for a job I do not want. My qualifications are my posts and comments. If you need references before you can respond to an opinion then you should only read articles of established journals.
While your paper is tangential to my steam of philosophical inquiry, it reignited some questions on my mind concerning merging dream and wake states. It is very important but I'll have to show my mind to work on it in my dreams.
thank you
I couldn't find this code. So I have to use quote or @. Where is this broken arrow?
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thank you :)
As for us or the other galaxies dong the receding, it doesn't matter if it is us or them receding. Those are just different choices of frames. Point is, separation between us is increasing.
Quoting Hachem
Challenging accepted view is fine, but doing so without bothering with the work of making some predictions (this idea makes plenty, and they all fail) is not science. Great minds do the work when positing something new. The rest of us get educated.
You have taken a very bad example for predictions. There are no predictions in this case, only conjectures. Cosmology is metaphysics with mathematical formulas. It is good of you to have confidence in Science. So do I. But I refuse to accept blindly what scientists tell me. Once again, even when all scientists agree on something it is still no guarantee that it is true. It is certainly an indication to take it seriously as long as there is no better alternative. But it should not be a reason to close our minds to other possibilities, how crazy they may sound at first.
The nature of perception, space, and duration must be reimagined in a completely new manner.
For example, perspective tells us what can be grasped and what cannot. By changing perspective, we are able to grasp. So if there field of action is holographic, the mind might not be "moving" but rather manipulating the perspective of the hologram. Understanding art and perspective provides some insight into this possibility. It may also be possible to better understand the nature of non-local action by flipping distance and reimagining it as perspective. It's a long shot, but nothing other than a complete 180 degree flip is going to provide insight into the nature of mind and perception.
I think you certainly should keep digging in this direction. My inclinations are different if certainly not opposed to yours.
Right now I am still wondering how distant stars can be reflected on our retina and how the moon can be reflected on a lake.
I am completely unsatisfied with the theory of the duality of light and will continue my reflexions and modest experiments with photographic gear (professional lab gear to study light is simply out of my reach), and see where that gets me.
Yes, I too have reflected on all this and have decided that the arts and holographic photography is the most useful direction to proceed. Science has to be turned on its head.
Bergson used photography as his model for explanation and Stephen Robbins reinterprets Bergson in a holographic setting. While Bergson modeled holography in his writings, it actually predates holography by many decades, so as with Da Vinci, he had a miraculous ability to See.
David Bohm describes in his essay on Creativity how paradoxes are resolved by flipping perspective. To solve these issues it is necessary to consider science moving 180 degrees in the opposite the direction of nature because it deals with matter not life. Bergson's critique of Relativity is brilliant beyond measure. Stephen Robbins covers it in one of his videos.
No one can "see" the universe in its entirety -- we are part of it, of course, or at least I hope we are -- and it exceeds our farthest reach of vision. Perhaps (or probably) some galaxies are already invisible to us, and will never be visible in the future.
The universe is a model, not a photograph.
Does the background microwave radiation help you at all? It appears to be everywhere, not evenly spread out. How would the big bang be consistent with a universe that was NOT expanding? How could something be "in the center"?
What is the relationship between a black hole and the space around and in it? Does it have space within it?
1) There is no duality. It is a wave (a real wave as discussed a hologram) and what is perceived as a particle is simply a wave perturbation (De Broglie-Bohm). As an aside, De Broglie was an admire of Bergson.
2) Zajonc wrote an interesting book on light called "Catching the Light". Lots of interesting bits of information that he collected but no insightful conclusions.
3) Don't think of light as propagate propagating in distance. Rather, as with Bohm's quantum potential, it is the form that is changing (similar to the way perspective creates distance). Thus, the canvas isn't necessarily getting larger or smaller, but rather the forms on it are changing.
You have to look hard for the problems with Relativity (Robbins-Bergson are a good starting point), but the upshot is that ontologically it is a mess despite. It should be considered only as a mild extension of the Lorentz transformation equations, no more. I often wonder whether Einstein's wife, a highly skilled mathematician during a time when women had no future in science, did all of the heavy lifting, especially since Einstein gave her all if the Nobel money. For me, Einstein was a pop star. Very unimpressive when it came to philosophy. His stance on QM was way off the charts.
It is my understanding that there is a great deal of the universe which is, even theoretically, unreachable from here because it is receding from us faster than the speed of light.
As to how that's possible, I've been confused. When I've asked how can some cosmological features be greater than 15 billion light years from us when the universe is only 15 billion years old, it's been explained that increase in distance caused by expansion of the universe is not the same thing as increase in distance as we usually think of it. Or that's what I think they said. Help someone.
https://www.space.com/33306-how-does-the-universe-expand-faster-than-light.html
Be out consider this, according to Special, an observer in any frame of reference can be considered at rest relative to other bodies in motion. Thus, according to Relativity, they are both exceeding the speed of light and at rest. I wonder what that must feel like?
For these reasons and many more, Relativity should not and cannot be given ontological meaning. They should simply be treated as transformation equations. What is actually happening it's beyond the c scope of Relativity. Ontologically, Relativity is a mess of contradictions, which are simply permitted by those who wish to give it ontological meaning.
I agree. If we were arguing over the tenth decimal place of some constant then maybe we would have something. But the foundation of the theory of our entire universe? Seems a bit incredulous. And yet, there seems no real answer to my question. I agree, we need the heavy hitters in to answer this properly.
Rich, you're pretty up on your quantum mechanics and physics in general. Where is the flaw in the premise that the universe could be contracting, based on the red shift or anything else?
Quoting noAxioms
This is what I am arguing. How does it look now? Again if there was shrinkage of space around the galaxies the blue shift could be compensated for.
Well, from the perspective of Special Relativity, how could anything bed contracting toward anything, since there is reciprocity between all frames of reference. There is no center! But then we switch to General Relativity which claims there are preferred frames of reference since one is supposedly accelerating while the other is not. Which one is accelerating?? So which SR or GR are we to believe if either? Can we use either for fundamental ontological knowledge, e.g. the universe is expanding. I don't think so. The theories contradict each other and cannot be brought under the umbrella of QM.
We certainly perceive changes in the Universe but everything about the standard scientific explanations, beginning with the Big Bang (the preferred center of the universe?) is flawed and can be questioned, so rather than try to solve the endless paradoxes (a twin paradox should not exist under SR, since both twins can be considered at rest relative to each other), I choose to ignore all of it, especially the notion of time and distance. I believe it is all wrong. I definitely don't take seriously the notion of faster than light galaxies.
Alternatively, ones can spend their life trying to solve all the paradoxes, and maybe have fun trying to come up with clever answers (which will necessarily contradict each other), but for me I rather pursue lines of thought that may prove more fruitful. My guess is that some point you'll also throw in the towel.
Yes, under SR time and length are reciprocal. Contraction of length is ignored leading to all sorts of paradoxes. So many, that I simply game up on Relativity. It would be like spinning my wheels in Zeno's. None of it is real.
Here is an interesting statement:
https://groups.google.com/forum/m/#!topic/fr.sci.maths/Gy09OKYu3Ss
The discovery is associated with Edward Hubble. It appears pretty solidly documented. I don't see any merit in doubting established scientific findings on the basis that 'it seems wrong', although there seems to be some controversy over the rate of the expansion, e.g. see here.
Quoting MikeL
It is shifting away from any point you happen to be whether that's Earth or some other location.
https://philpapers.org/post/18962
edit: even though it is not exactly about the expansion of the universe, it concerns light and how it is conceived. That's when my interest started in the subject of light.
Another point, developed in Canales book:
https://www.amazon.com/Physicist-Philosopher-Einstein-Bergson-Understanding/dp/0691173176
Time in SR is not time in GR, but explanations of Relativity paradoxes bounce back and forth as if they are. In GR there is this concept of space-time while SR uses time in the more traditional meaning found in Newton's equations.
The upshot is this. One can spend their life trying to iron out Relativity by trying to explain all of the paradoxes, as one forever tries to figure out solutions to Zeno's (nothing wrong with this), or one can use the paradoxes as a red flag that something is very wrong (Bohm's suggestion) and forget about it. I chose the latter and instead I am following the ontological path laid out by Bergson. The same with QM. Rather than deal with superposition and wave collapses, I just choose Bohm's quantum potential and non-locality. The two ontological paths actually come together quite nicely.
I'm not arguing he saw the red shift Wayfarer. I'm arguing that the red shift does not necessarily imply an expanding universe. Maybe all of the galaxies are shrinking on the spot! Same effect, don't you agree? Maybe there are all contracting away from each other toward the center of the universe - again same effect.
If these can't be proven false, then the entire Big Bang to Heat Death is one theory predicated upon a weaker one.
Quoting Rich
If this is the best evidence physics can offer about the expanding universe, red blurs in a telescope and conflicting equations, it seems like the premise and the entire multi-story list of deductions that come from it, is balancing on a single egg shell. - All because of a bit of red out there.
Early on, I learned that if there are paradoxes and a steady stream of inconsistencies, the theory is flat out wrong, and what is needed is a new way of looking at the problem. That is why Bohm's QM solution is so straightforward and brilliant in nature.
So it comes down to this. Relativity helps address some measurement problems, but no more. There are two definitions of time used in SR and GR and the theories inherently contradict each other and are internally inconsistent. So for developing an ontological theory of nature, they are useless and any attempt to use any aspect of Relatively in a metaphysical model, especially Time, will simply confuse and lead in the wrong direction.
If you are looking to spend time trying to unravel the Relativity mess and amuse yourself and others with all of its contractions, then you have hit the mother lode. If you want to get on with the business of understanding the nature of nature, then just forget it and all cosmology that depends upon it, and look for more fertile grounds. No time can be better spent than thoroughly understanding Bergson and Bohm (and Sheldrake, if you are biologically bent), and with this knowledge begin to construct an interesting metaphysics. You really don't need a better foundation. After that, study and art so that you can begin to see nature deeply as it is. Tai Chi would be equally useful. Mathematics is unnecessary, since no amount of mathematics can ever capture the richness of nature. It doesn't even scratch the surface. What you need is a super keen sense of observation and a well developed creative intuition.
It's a big deal, as it means we need new theories for everything to do with space, dark matter, dark energy all of it, or at least alternative theories. No wonder they keep invoking new stuff to explain inconsistencies.
But are we sure that there is no other supporting evidence? If not, wow!
SR and GR are not different...
This seems to be very pseudo-scientific right here. SR is a special case of GR, which occurs mainly when we're dealing with flat, non-curved space.
anyone. I am interested, in this case at least, in direct feedback on the argumentation, and much less on a general discussion, which I also consider as important, of RT and QM. In other words, are the arguments I am using solid or fallacious?
On what grounds? My cousin thinks Einstein has it all wrong. He drives a cab.
To answer the question though, on the ground that the shift is caused by one object moving away from the other. One explanation is that it is moving away from you very fast, or another explanation is that you are moving away from it very fast. Directionality is the key here. They could also all be contracting toward their centre, in which case they are also all moving away from each other.
I'm not going to get too much into the confused mess of GR and SR, because no one can provide good answers. Only three people understand Relativity and none agree.
The wonderful world of Relativity.
https://www.space.com/33306-how-does-the-universe-expand-faster-than-light.html
"The notion of the absolute speed limit comes from special relativity, but who ever said that special relativity should apply to things on the other side of the universe? That's the domain of a more general theory. A theory like…general relativity.
It's true that in special relativity, nothing can move faster than light. But special relativity is a local law of physics. Or in other words, it's a law of local physics. That means that you will never, ever watch a rocket ship blast by your face faster than the speed of light. Local motion, local laws.
But a galaxy on the far side of the universe? That's the domain of general relativity, and general relativity says: who cares! That galaxy can have any speed it wants, as long as it stays way far away, and not up next to your face."
https://en.m.wikipedia.org/wiki/Time_dilation
"Contrarily to velocity time dilation, in which both observers measure the other as aging slower (a reciprocal effect), gravitational time dilation is not reciprocal. This means that with gravitational time dilation both observers agree that the clock nearer the center of the gravitational field is slower in rate, and they agree on the ratio of the difference."
https://en.m.wikipedia.org/wiki/Theory_of_relativity
General Relativity
"The upshot of this is that free fall is inertial motion: an object in free fall is falling because that is how objects move when there is no force being exerted on them, instead of this being due to the force of gravity as is the case in classical mechanics.This is incompatible with classical mechanics and special relativity because in those theories inertially moving objects cannot accelerate with respect to each other, but objects in free fall do so. To resolve this difficulty Einstein first proposed that spacetime is curved. In 1915, he devised the Einstein field equations which relate the curvature of spacetime with the mass, energy, and any momentum within it."
It might be worth posting this on Physics Forum.
The standard cop out is with a wink and a smile, someone will proclaim that only the people understand GR. I actually think that is three too many. It is an error to assume science had it all worked out and laypersons simply don't understand it. On the contrary, it it the laypersons who usually unearthed all of the contradictions with simpler, straightforward questions. Beyond this, as in other link I offered, there is now an experimentally testable theory that the speed of light is variable. Always new things.
At end, one can spin their wheels forever in Relatively, or just move on and not bother with it. I just feel that it is an unsolvable riddle and eventually be overturned. Bergson's critique made 1000 years ago was spot on.
https://physics.stackexchange.com/questions/134417/is-special-relativity-a-special-case-of-general-relativity-qualitatively
I can confirm this attitude in Physics forums. They are very good at regurgitating textbook knowledge and abhor critical questions. I have even been banned just for daring claim that Optics is not necessarily correct. My confidence in critical thinking among scientists, whether forum users or academics, is very low.
The same is true in GR.
If you look at the link, you will observe that GR is used in the explanation for galaxies accelerating faster than light, even though SR denies the possibility.
I really try to refrain from arguing Relativity because unlike QM which is simply the Schrodinger equation, Relativity it's a mass of conflicting ideas which truly no one agrees on. Every single answer is different.
No it doesn't. Spacetime itself expands faster than light, but spacetime isn't actually an object the way galaxies, planets, etc. are. Galaxies, etc. travel in spacetime, but spacetime doesn't travel in anything.
Space-time are defined differently in SR and GR.
Really, it is off no use. I provided the link which clearly states the contradiction. That you disagree with the link's description underscores my point. Are we to begin yet another neverending discussion on the meanings of SR and GR. They already exist by the thousands on the Internet. Another one would be superfluous.
Yes of course they are! What did you expect? It's like telling me that space is defined differently in Euclidean and Non-Euclidean geometry. This of course doesn't change the fact that Euclidean geometry is nothing but a subset of Non-Euclidean geometry, just like SR is a subset of GR which applies only in a LIMITED set of circumstances/conditions.
Quoting Rich
This one?
Quoting Rich
That 'contradiction' was resolved by GR. That's why GR was invented.
At some point in ones life one must decide to say the "heck with it". It is a confused morass of ideas and opinions and it is better just to ignore and move on. Anyone interested in the subject is invited to investigate on their own. Who better to demonstrate nasal if the contradictions than the physicists themselves.
I suggest then that SR be completely dropped and all that it implies. That will really eliminate the contradictions!
SR has been dropped when GR has been adopted. Really... you seem behind on science.
The only reason SR is taught is the same reason Euclidean geometry is taught. They are applicable in specific circumstances, but not in all. If you want something applicable in all circumstances, you go to GR and non-Euclidean geometry respectively.
See this? GR is in Space Curvature.
Whoops! All those books on SR need to be pulled from the library shelves immediately. This can be a PR nightmare. What should we do about the millions of references on the Internet?
Are you doing this on purpose?! Do all books on Newton's theories have to be dropped out of the library because his theory has been replaced by GR?! Do we need to get rid of Euclid's Elements because Euclidean geometry has been replaced by Non-Euclidean geometry (which by the way, also includes Euclidean geometry itself?)?
Exactly how many areas of the universe are without gravitational space-time?
Really, must we go through this?
None, that's why SR, much like Newton's theory and Euclidean geometry provide USEFUL approximations. They're easier to work with and calculate than their more complex parents.
All of the implications of Newton's theories contradict SR. You can't say there is a preferred frame a reference (Newton), then say there isn't (SR), and then say there is (GR). You can't say nothing can move faster than light and then say whole galaxies can. Actually, you can, because that is exactly what Relativists are doing.
It is a mess.
It seems you are confused. When I assume that the internal angles of a triangle are 180 degrees and proceed to calculate using that assumption, I don't actually think it's true. Absolutely not. I think it's an approximation of the truth, which is good enough to give me an estimate for the answer that I'm looking for with sufficient precision for my needs.
Quoting Rich
Sure. So what? Newton isn't applicable where SR is applicable, BUT SR is applicable where Newton is applicable. Likewise, SR isn't applicable where GR is applicable, but GR is applicable where SR is applicable.
Beware, as Bergson warned, do not give Relativity and any of its implications, ontological status.
When you say this, it's just as silly as telling me to drop Euclid's 5th Postulate when doing Euclidean geometry because it's not true. Absurd.
Yes, it's not true. But that assumption approximates local conditions sufficiently such that it is useful.
Yes, but this belies a complete misunderstanding of how science works. Science doesn't work by finding out what is "true". It works by approximating what is true. It says for this group of situations, things behave as if the internal angles of a triangle add up to 180 degrees because the curvature of spacetime is almost 0.
I wouldn't have any problems with that. Only, as Rich indicated, RT and QM come with ontological claims and so does contemporary science. This thread is a clear example of these ontological claims. Is the universe expanding? That is neither merely an assumption, nor an approximation but a hard claim that the universe as we know it is expanding.
That is what I meant with cosmology is metaphysics with mathematical formulas, and that is what I think Rich means when he says we should beware giving ontological value to RT and QM
This was the essential object that Bergson had to Relativity. Robbins raises the same objection.
It is one thing to say that the equations are useful. It is quite another to elevate the equations to an ontology.
It depends which equations you elevate to ontology. You should elevate the most general framework. In the case of gravity, this would be general relativity, and NOT special relativity or Newton's laws.
How about space-time? Should it be elevated to an ontology?
Spacetime effectively is GR.
is that a yes?
Yes.
Nope, Rich has a problem with SR, not with GR.
I won't speak for Rich, but I find the concept of space-time a metaphysical monstrosity.
Why?
Well, physics obviously speaks about physical time that can be measured by a light clock which is invariant regardless of frame of reference.
This is indeed different than the experience of time which philosophy talks about. Why do you conflate the two?
I don't, Einstein does, and before him his teacher that invented it.
But will subjective time appear to flow twice as fast? I think so.
But a materialist determinist like Einstein wouldn't necessarily agree because if everything speeds up, the processes in the brain, which according to them are responsible for our subjective experience of time also speed up. So relative to their new speed, we will perceive no change in our subjective experience of time. That would be the argument I would say.
I already know the argument, and it is the most ridiculous thing I have ever heard. Ask biologists.
Why do you say that?
Biological, and certainly psychological processes are what they are because of their rhythm, change the rhythm, and you will make organs work two times harder, age two times faster, and emotions completely change from quite to frantic.
edit: the difference between I did it my way by Sinatra and the other guy, the dj?
Yes, but if materialism were true (which is what we have to assume for their explanation to make sense), then your subjective experience of time flowing at such and such a rate is created by the correlation of the speed of movements in your brain with the speed of movements outside your brain. If both of them increase at twice the speed, your subjective experience will not perceive the increase.
assume further my dear sir.
I have no knowledge of cosmology, this is simply a poetic possibility.
As T Clark points out back at the start, if the red shift was just us moving towards some mythical centre, then we would also be approaching other galaxies, creating a blue shift. And even if they were moving faster ahead of us for some reason, the resulting red shift would not be as red as galaxies in the opposite direction.
Then if it was instead just our galaxy collapsing inwards, we would have collapsed long before now. And also all the other galaxies would look redshifted equally regardless of their distance. They would all appear to have the same velocity, not a velocity that appears to accelerate until it eventually goes super-luminal (faster that lightspeed) and so get swallowed up by a cosmic event horizon.
So there are a whole bunch of astronomical observations which are simplified best by believing that what we see is an expanding/cooling universe. And science says the best theory is the one that accounts for the most variety with the least explanatory effort. We have no good reason to doubt the expanding/cooling universe hypothesis.
There is not just one observation that demands the theory. The theory is the only one that makes sense of everything we so far observe.
Remember Olber's paradox. If the universe is infinite and wasn't expanding we would be blinded at night by the blaze of every star in the cosmos. Thank goodness for event horizons that means we only see a finite number of those stars and so can sleep in the dark.
Yes, it is nice to reimagine every physical claim from its other angle, tell the same story in reverse. That is what physics gives you - reversible stories that thus connect starting conditions to final conditions in a predictable way. But if you actually try to understand the physics backwards, then you will become prone to all kinds of metaphysical error.
So red-shifting was the big clue that forced the reach for a good explanation. But there were already other reasons, like Olber's paradox.
General relativity also created an issue of how the Universe could be stable, given that it either had to be gravitationally collapsing, or for some reason expanding. We could guess it wasn't collapsing because otherwise our odds of being here to witness its existence would be infinitesimal (given infinite time, at any particular moment, collapse would have already occured with matching probability). So that only left expansion as the reasonable guess.
And now - surprise - Einstein was righter than he knew on that score. We have discovered a further observation, what has been dubbed dark energy or the cosmological constant, which tells us metric expansion is wired into the fabric of being. Expansion forever is a hardwired-looking fact now.
So as I say, physics ain't dumb. The expanding Big Bang universe was predicted by theory as much as it was necessitated by multiple lines of observation. Once Einstein cracked GR, expansion had to be the case somehow.
I personally have no problem with the idea of a universe expanding. After all, it is as reassuring or scary as the idea of a finite world. A little like being afraid to reach the end of the earth and then fall off in the emptiness.
What we are talking about is the ontological value of cosmology. You are convinced of the veracity of the whole story, while others in this discussion are not. Again, I could buy into the idea of an expanding universe. What I do not buy in are the current cosmological theories.
I was explaining why cosmologists, as a pragmatic community of inquiry, would proclaim themselves convinced.
You are free to dissent. But your dissent only counts as reasonable if you can show you understand what is being said, and why, then make some other case in that light.
Otherwise its all fake news and alternative facts, as they say.
Please read the previous posts. You barge in and expect us to start all over again. That is not reasonable.
Thank you. But I was just about done. This was a side-street I was walking, with no real definite end to it.
I have, in another forum, spent as much time and energy that I could, based on my non-physicist background. And metaphysical debates have the annoying property of having no end. There are no knock out arguments for me to hit you with, and I do not think you have any in your possession either.
But it's all right, such an open ending is exactly what makes science interesting as far as I am concerned. What worries me is the theological devotion of people who call themselves scientists or materialists. BTW, I am old-fashioned, and for me materialism has more of a socio-political connotation than a metaphysical one. I have always felt closer to Marx than to Engels.
I find metaphysical materialism as is known in, among other places, American universities, as simplistic as Engels' attempts at philosophy.
Can't talk long as I'm at work. The resultant red shift intensity would be relative to the speeds of objects. It could be that they are both red shifted equally, one is blue one is red, or one is more red shifted than the other, surely.
If the entire galaxy was not collapsing, but rather shrinking (space shrinkage), the we could observe the red shift.
Sorry for the brevity. Do you get what I'm saying?
Nope. Your scenario would predict inhomogenities in red-shifting that we just can't see. If it is our relative motion that causes the effect, then we couldn't be moving towards some things without moving away from other things. There would be no way to conceal that fact.
The red shifting is just too precise and well behaved in every direction for our motion to be the cause.
You could imagine an inverse physics where instead of spatial expansion causing this even outward flow the story is that every point of space is contracting inwards. So the universe is a constant size in the global sense, but every point within it is shrinking smaller. That is kind of your contracting galaxies story.
But that would predict the sun and the milky way stars all receding from us too. Every point in space would have to be contracting inwards .... at lightspeed .... to invert the same physical picture.
As I said, actual galactic structure couldn't still exist. It would have all shrunk out of our sight. Even the good old sun would be a light-day "more distant" from us each morning when we wake up. Not to mention that we would have to junk quantum mechanics and its claims that physical action is tied to some actual minimum Planckian scale.
So your conjecture predicts observables we don't observe. And in the case of the sun rising tomorrow, the degree of error in the prediction is not small. It is astronomical. :)
https://resonance.is/observational-tests-holographic-cosmology/
"Quantum gravity offers such new physics unifying the cosmological and quantum scales and providing a complete model of our universe. However, although a consistent and validated model has yet to be agreed upon, it is expected to be holographic – that is the information of a volume of space is encoded on a boundary surface – as suggested by Nassim Haramein’s theory of quantum gravity, although the boundary surface is not regarded as literally 2-dimensional as it is comprised of 3D spherical planck oscillators. Now for the first time a team of scientist’s present observational proof that the Universe could well be holographic."
http://phys.org/news/2017-01-reveals-substantial-evidence-holographic-universe.html
"A UK, Canadian and Italian study has provided what researchers believe is the first observational evidence that our universe could be a vast and complex hologram."
https://arxiv.org/abs/1610.06236
"We show that the holographic principle can be understood heuristically as originated from quantum fluctuations of spacetime."
http://www.swansea.ac.uk/physics/researchgroups/particlephysicsandcosmologytheorygroup/holographyandphysicsbeyondthestandardmodel/
"Recently, the group began to apply the ideas of holography also to the construction of viable models of inflationary cosmology."
Yeah, I have no problem with that if it is the case that we have not actually observed any motion but only a snap shot through the telescope. Our time scale v the universe time scale suggests we've not tracked from A to B yet in our observations.
It well may be the case that space is contracting. Have we observed the reverse of any of this either? I mean are we a light-day "closer" to the sun every day, to take the opposite view of your example?
I don't know about the Plank scale. I'll have to check it out.
So the Universe may be LIKE a hologram. No one is saying the Universe IS a hologram. (Outside of the usual misleading reader-grabbing headlines.)
"A UK, Canadian and Italian study has provided what researchers believe is the first observational evidence that our universe could be a vast and complex hologram. Theoretical physicists and astrophysicists, investigating irregularities in the cosmic microwave background (the 'afterglow' of the Big Bang), have found there is substantial evidence supporting a holographic explanation of the universe -- in fact, as much as there is for the traditional explanation of these irregularities using the theory of cosmic inflation."
http://m.nautil.us/blog/new-evidence-for-the-strange-idea-that-the-universe-is-a-hologram
"In their paper, published last month in Physical Review Letters, the team report the holographic model fitting the Planck satellite data slightly better than the standard model. The results don’t prove the universe is holographic, but they are consistent with a holographic model."
"Professor Kostas Skenderis of Mathematical Sciences at the University of Southampton explains: “Imagine that everything you see, feel and hear in three dimensions (and your perception of time) in fact emanates from a flat two-dimensional field. The idea is similar to that of ordinary holograms where a three-dimensional image is encoded in a two-dimensional surface, such as in the hologram on a credit card. However, this time, the entire universe is encoded!”
https://www.sciencealert.com/this-might-be-the-first-observational-evidence-that-our-early-universe-was-a-hologram
"So like a 3D hologram projected from a two-dimensional screen, the hypothesis states that the three dimensions of our Universe were projected from a two-dimensional boundary.
Since 1997, more than 10,000 papers have been published supporting the idea, so it’s a lot less crazy than it sounds.
Now Afshordi and his team report that after investigating irregularities in the cosmic microwave background - the 'afterglow' of the Big Bang - they’ve found strong evidence to support a holographic explanation of the early Universe.
"Imagine that everything you see, feel, and hear in three dimensions (and your perception of time) in fact emanates from a flat two-dimensional field," says one of the team, Kostas Skenderis from the University of Southampton in the UK.
"The idea is similar to that of ordinary holograms, where a three-dimensional image is encoded in a two-dimensional surface, such as in the hologram on a credit card. However, this time, the entire Universe is encoded."
https://philpapers.org/post/17142
edit: maybe more to the point, I found those two posts that more directly relate to the phase of the discussion. But let me state that I have no opinion on whether the universe is a hologram or not. I am afraid it is way above my pay grade!
https://philpapers.org/post/17290
https://philpapers.org/post/17298
When I am driving, and observe out of my windshield, I see a two dimension space that is changing with duration. It is like a moving picture. This experience is much different than one when I try to map my coordinates using measurements where I used coordinate axis as you describe. Describing an experience is not the experience itself, which is why I continue to believe that mathematics does not provide an ontological view of the nature of nature's. It gives the opposing views. This is fundamental because living and experiencing is beyond the reach of measurements.
Now, scientists are beginning to look at the universe differently. As a hologram with one less dimension than conventionally understood space. A bit closer to the actual experience but ultimately whatever science comes up with will necessarily rely on mathematics and thus will be far from experience. Mathematics is only about partitioning and measurement. It cannot capture living experience. The only way to understand the living nature is via direct observation coupled with intuition
I think you should remember that we are talking about science, and not experience. The discussion which of the two is closer to reality sounds like a metaphysical conundrum. Don't make it a competition between knowledge and intuition like Bergson much too easily did. As far as I am concerned, they feed on each other. Knowledge is as primitive as intuition, and to be able to gauge distances is a condition for survival.
The basic tools of science always begin with a new creative insight and it's a continuum, but the tools are not a prerequisite for understanding, they are only tools to play with.
The Daoists, who were great observers, developed a tremendous understanding of the nature of life. What they couldn't do is kill millions of people with a single gadget. That took a better understanding of chemistry (which begins with direct observation and intuition, e.g. alchemy). Unfortunately, much ancient knowledge which is quite superior is being lost. The good news is that it can be recovered by direct observation and creative intuition.
I am afraid I do not share such a romantic view of ancient knowledge.
nothing wrong with that.
How can Apokrisis be barging in? Back on Page 1, I asked him to participate:
Quoting T Clark
No, directionality doesn't really matter in that sense, since everything is moving away from everything, as the evidence suggests.
Quoting MikeL
No, I don't think that that's right. In that case, they would not all be moving away from each other. The movement can be visualised if you imagine a cone, with the tip of the cone being the centre to which the points are all travelling. Or if you imagine the rings on a tree trunk. The closer to the tip, or to the centre, the closer together the points would be, eventually.
Expansion, further apart; contraction, closer together. Although it's not as simplistic as that because of the differing speeds, collectively, that's how it would be.
Under general relativity, the universe could be expanding or contracting. GR equations famously have symmetry in that precise regard. They don't specify a direction, so both directions make sense.
However the two directions make different predictions once we add in a conservation of energy constraint. Now one direction will cool radiation by stretching it, or redshifting it. The other will heat radiation by contracting it, or blue-shifting it.
So we looked up in the sky and saw unambiguously which it was. The Universe is redshifting evenly in every direction. At most, this would mean the earth just happens to be standing still as it sits right in the centre of the universe and everything else is for some reason moving away with ever greater speed according to it distance. So everything else is not just moving with some constant velocity but is carefully arranged so that velocity is faster the further away the object happens to be.
This kind of Copernican special arrangement doesn't generally make good science. It is simpler to believe that space expands the same for everyone everywhere at the same local rate. There is no centre to the expansion, and so no need to locate the earth in exactly that one spot.
Then again, even if the earth is in this special Copernican situation, we are not seeing the blueshift a generalised contraction ought to predict. The stars are not carefully arranged so that the most distant look to be rushing towards us the fastest.
No, the dots would not be contracting away from each other, except in the very limited sense, which I acknowledged, that [i]some[/I] dots would be moving away from [I]some[/I] others, because they'd be travelling at different speeds.
Collectively, however, they'd all be drawn towards a single point, the centre, and thus they'd ultimately be getting closer together, as they would in a reverse Big Bang. They'd all be headed towards the same destination, not away from it; and they wouldn't all be moving away from each other, as illustrated in the balloon demonstration. Or, to go back to the tree trunk, each of the rings on the tree trunk would shrink inwards towards the centre.
When you talk about contraction, I think of a Big Crunch scenario. What other scenario could it be?
If it's perfectly symmetric there is no blue shifting. The opposite of space itself expanding is space itself contracting. Because everything in that space is also contracting, there is no heating. The galaxy will not pull away from us, anymore than it is drifting towards us now under an inflationary model. The contraction doesn't have to be directional toward a centre point.
If it can be agreed that it can happen, then I can suggest one way it will change our understanding of science.
In my model the centre is shrinking the fastest, but there is no single centre as all of space is contracting. So throw the 1980s checkerboard cloth over space and then contract all of the checkers. The ones in the centre smallest, the ones on the outer fringe the largest. The checkerboards don't overlap, there is no compression as all of the space inside the checkerboard is contracting too.
In the checkerboard table cloth each checker would be pulling away from its checkerboard border and contracting.
No, I suppose not, but that'd make more sense, wouldn't it? I'll go with what makes more sense. Anyone can come up with ideas like that or like your petrol can, but if they don't really add anything, or, worse, if they actually detract from what we have, and create more problems than resolutions, then that doesn't go in their favour. Raising possibilities is one thing, solving problems is another.
Quoting MikeL
I still don't understand how you're reaching that conclusion.
It apparent growth in the ratio would be a summative effect over distance. Apokrisis has steered me right though on this point. You are welcome to check out the previous comments.
Quoting Sapientia
Go on, check it out, and then tell me that I was full of shit.
That's the conclusion. I'm asking you how you got there, but instead you're just repeating it, which wastes both of our time. You made the claim, and I've challenged it. The burden is on you. Are you incapable or unwilling?
I could look further into it on my own, but if you said it, then it's charitable to give you the benefit of the doubt that you know what you're talking about and can answer my question.
Quoting MikeL
I have. He said that you were wrong.
I looked up the article about blue shift, and I understand what that means:
The other article he linked to was about expansion, but my query is about what you've said in relation to contraction.
Honestly Sapientia, I'm unwilling. I could explain to you what I mean in more detail, I usually enjoy doing that a lot, but I do not think you have come here and are asking these questions in good faith, which is disappointing. Initially I did think you were interested which is why I included you in my responses.
I thought you were trying to be objective and were interested in the subject, but now I think you're just fishing about for something that makes you right and me wrong. I don't like that attitude in people - it's about as closed minded as you can get. The forum is about the exchange of ideas, Sapientia.
Regarding the comments you made about my other OP in this thread, I found them unnecessary and aggressive, and I have directed you to the reposted OP to ask if you stand by the claims you made earlier of not having enough knowledge or qualifications to broach the subject and whether you think it is still bizarre arm chair science. You've not answered, and I suspect that any answer you give will try and support your position - perhaps in a sentence I didn't dot an 'i' somewhere. You just can't admit you might have been wrong about me. I have no respect for that.
Never mind. I will look further into it myself.
[/quote]
So, there we have it. Einstein's equation shows that the universe [I]must be[/I] expanding, and this expansion has been observed.
The more we learn about Einstein's equation, the better our understanding of why it is that the universe [I]must be[/I] expanding.
Or, perhaps this recognised theoretical physicist has got it wrong.
[quote=Carlo Rovelli, Seven Brief Lessons On Physics]All of this is the result of an elementary intuition: that space and gravitational field are the same thing. And of a simple equation which I cannot resist giving here, even though you will almost certainly not be able to decipher it. Perhaps anyone reading this will still be able to appreciate its wonderful simplicity:
[I]R ab ? ½ R g ab = T ab[/I]
That’s it.
You would, of course, need to study and digest Riemann’s mathematics in order to master the technique to read and use this equation. It takes a little commitment and effort. But less than is necessary to come to appreciate the rarefied beauty of a late Beethoven string quartet. In both cases the reward is sheer beauty, and new eyes with which to see the world.[/quote]
I am not saying it is not. I have no way of knowing that.
It is just that the whole argumentation, just like the whole of cosmology, depends on whether light is like the theory says it is.
All my threads attempt to show that this is far from obvious and beyond doubt.
That's an over-simplification by Rovelli.
As he does state in his first sentence, general relativity's field equations don't define a direction. The Universe could be expanding or contracting.
And Einstein's first thought was that - because of the Universe's gravitational content - it would naturally be contracting. Einstein believed the Universe ought to be eternal and standing still, so he added an extra term to his GR equation - the cosmological constant - as an extra mystery force required to exactly counteract that gravitational collapse and so allow the Universe to be static.
It was an embarrassing kluge factor. It couldn't even work as this static solution was so unstable that the universe would have to tip over into gravitational collapse with the slightest inhomogeneities in the spread of gravitating matter.
But then it turned out from observation - red-shifted stars - that the Universe was in fact expanding. So that wasn't predicted by anything in Einstein's equations. Although it was certainly allowed. And the Big Bang theory was born, where now there had to be a fantastically accurate balance between the outward force, the kinetic energy, of "an explosion", and the contracting force of any gravitational contents - the total mass of the Universe.
Roll forward and the Universe proved to have only about 30 per cent of the required mass at best. Then observation suggested the solution - dark energy, a repulsive force creating a faint acceleration at every point of space. And now this had to be incredibly balanced or fine-tuned ... due to some quantum explanation so far eluding physics.
So expansion is certainly a reasonable conclusion. It is what we see when we look at the stars and galaxies.
But gravity says basically things ought to be contracting. And then a static Universe - the most "obvious" presumption - is impossible. Eternal existence is ruled out as a maximum improbability.
And if there is the third option of expansion - as there really must be just because it is both what we can see, and what is most probable given the Universe has been around long enough for us to be even wondering - then this expansion must be most remarkably fine-tuned. The expansion - or indeed now, the acceleration - is adjusted to be exactly the amount needed to make the Universe almost perfectly flat and future eternal.
The details are worth going into as this is a cosmic scale whodunnit. It shows how poor our metaphysical intuitions can be. It shows why proper science is actually needed. :)
So MikeL I would credit for at least having a go at being bothered by the basic claim - why is the Universe expanding rather than shrinking?
The actual physics has long moved on. The question now is why is it faintly accelerating by some precisely correct amount to make up for the 70 per cent of "missing mass". There is plenty of speculation about possible answers, but right now it is simply a really big and interesting gap in our scientific knowledge.
Well actually you do if the predictions of the models match the experience of the observations.
Quoting Hachem
That is why they are crackpot in the sense of just not understanding the nature of scientific claims.
You are always aiming your doubts at the apparent intuitive content of scientific theories, when it is only their theoretical structure that counts. That is the very definition of tilting at windmills.
That is why there are cowards that only choose what seems to make them sound right, and refuse to look at alternatives.
That is why Einstein said to his audience of scientists " yesterday you all believed in the ether".
You belong in that audience. You are not a scientist but a bigot.
Perhaps you could justify your approach based on an actual philosophy of science argument? Science is happy to consider alternatives. But they do need to be scientific ones - some formal proposal, not simply angry arguments aimed at apparent intuitive content.
If you have a formal alternative, I've certainly missed it. But then I quickly gave up reading your posts after responding with care to your first and finding you seemed only interested in manufacturing bizarre interpretations of existing successful models.
nope. I am done with your ( you and the Friends) evasive maneuvers. Let us talk empirical facts instead of theoretical generalities.
As I say, you are just making half-baked attacks based on your own intuitive beliefs. That is not how science works. It is how psychoceramics works.
Sorry for this side show. I will refrain from further off-topic comments.
(From [I]Seven Briefs Lessons On Physics[/I] by Carlo Rovelli).
As one can tell from these pictures, according to these models, a smaller-sized ball of the universe would contain stars with a shorter distance between them than those of a larger-sized ball of the universe. The smaller-sized balls represent either an earlier stage in an expansion or a later stage in a contraction, and vice versa with regards to the larger-sized balls.
This was my earlier point.