How much geometry to do you know? You don't know any.Ignorance is one thing but boasting of it is another. How many shapes can be uniform and expand evenly over their whole area? Well, there's a sphere and there's .......?
You really don't have a clue, do you? You just jump at a subject and cut and paste in any idea that your poor, poor brain thinks might work.
All of the cosmologies with more than 3-spheres are hyperspace models. The surfaces of hyper-spheres can themselves mathematically contain 5-spheres or 6-spheres or any n-sphere. The resulting universe, though quite unimaginable beyond strictly mathematical models, is possible if nature somehow can comply (har har).You are just C&P-ing ideas here. A hypersphere is 100% uniform. No other shape is. If you did have a clue, you would know that. Telescopes show no anomalies which would be produced by any other shape.
We are not talking the curvature of space in that sense. The universe would be a 3D skin on a 4D expanding hypersphere.
No, I do research in orbifolds, which are the quotient spaces of tori, as well as beginning work on generalisations of Calabi Yaus and I'm also doing a side project on the AdS/CFT correspondence in the space-time topology of $$AdS_{5} \times S^{5}$$.You are just C&P-ing ideas here.
Minkowski and AdS space-times are 100% uniform too. They have constant curvature everywhere. Telescopes give no evidence the universe is closed, in that if you travel far enough in one direction you return to where you started, which is what would be the case if the universe is a hypersphere. Since we don't see the same exact structures on opposite sides of the sky, we have no evidence for it being closed.A hypersphere is 100% uniform. No other shape is. If you did have a clue, you would know that. Telescopes show no anomalies which would be produced by any other shape.
The boundary of a solid 4D ball is a 3d sphere. For instance, suppose you have a solid ball in your hands. The surface of the ball is a 2-sphere, so the boundary of $$B^{n}$$ (B being 'ball' and n being the number of dimensions it has) is $$S^{n-1}$$. There's a topological distinction between a ball and a sphere.We are not talking the curvature of space in that sense. The universe would be a 3D skin on a 4D expanding hypersphere.
No, I do research in orbifolds, which are the quotient spaces of tori, as well as beginning work on generalisations of Calabi Yaus and I'm also doing a side project on the AdS/CFT correspondence in the space-time topology of $$AdS_{5} \times S^{5}$$.
I've given talks on orbifolds and Calabi Yaus, see my website. And professors don't think I'm copying and pasting and they actually know about my work. You just say "It's not original" when you don't even know what I actually do.
Minkowski and AdS space-times are 100% uniform too. They have constant curvature everywhere. Telescopes give no evidence the universe is closed, in that if you travel far enough in one direction you return to where you started, which is what would be the case if the universe is a hypersphere. Since we don't see the same exact structures on opposite sides of the sky, we have no evidence for it being closed.
Infact, if dark energy exists then it cannot be closed, instead it would be open and so ever so slightly AdS. That's what telescopes tell us at the moment.
The boundary of a solid 4D ball is a 3d sphere. For instance, suppose you have a solid ball in your hands. The surface of the ball is a 2-sphere, so the boundary of $$B^{n}$$ (B being 'ball' and n being the number of dimensions it has) is $$S^{n-1}$$. There's a topological distinction between a ball and a sphere.
As I've said, if the universe is $$S^{3}$$ and we had evidence for it then we'd see identical structures on opposite sides of the sky, just as if you travel far enough around a globe in opposite directions you end up at the same place. But we don't. This means that either the universe is a HUGE closed object (of which a hypersphere is just one kind) and light hasn't managed to travel around the entire 'surface' yet to show us the same objects on opposite sides of the sky or that it's another kind of topology, which isn't closed like flat, ie Minkowski, or it's open (as supernova observations tell us) and so is AdS.
Can you provide evidence the universe is closed, in that light can travel all the way around the sphere and get back to us, or are you just going to fail to understand all I've explained and just deny it all?
Can you prove I've copied and pasted anything in this post? It's called 'learning'. It's what educational institutions facilitate. As do books. Try using them some time.
Hi Kaneda,The work you have had printed in various journals because it is original is.....?
Where did I claim to that?The work you have had printed in various journals because it is original is.....?
Firstly, the overall curvature of the universe is an averaging factor. Local variations obviously occur due to local variations of matter. The metric which describes the space-time around the Earth is the Schwarzchild metric, but over large distances where th effects of space-time expansion and dark energy dominate, you get AdS.There is a billion light year area of emptiness. It is craziness to say that curvature is the same here since there are no gravitational sources to cause it.
So infact we have no evidence the universe is a hypersphere at all, because we don't see such phenomena in observations. So it could be, overall, flat or even open, thus not a hypersphere. Hence why the BB model isn't "It's a hypersphere". That was a claim Nick on PhysOrg kept pushing but was corrected many times.Since the limits of our telescopes are not much over 13,000,000,000 light years, we could not see something fifteen billion light years away let alone the backs of our necks.
Just like quantum field theory was a convent idea to fill the gap of electromagnetism, allowing us to make new, better, predictions and working models and then standing up to test.If DE exists? We have no proof it does. It is a convenient idea used to fill a gap.
A flat plane can still undergo a space-time expansion. Infact, if you look at the FRW metric, which describes an expanding universe, there's a parameter in it called K. Depending on the value of K (<1, =1 or >1 if memory serves) you end up with spherical, flat or AdS topologies for your expanding system. So there exist ways of putting all these kinds of general space-time into expansion models.An expanding hypersphere is not a closed universe (but a finite universe) because it is expanding. perhaps you would like to explain how expansion works, where the space between galaxies expands without using a hypersphere?
Their properties due to their distance match the predictions of expansion not 'tired light'. 'Tired light' doesn't explain the time dilation effects we also observe, which occurs in relativistic models for two reasons, the speed the IAs are moving away from us and the expansion of the space-time as their photons moved towards us. The combined contribution of these two effects are seen experimentally. Can you find me a tired light model which explained both?As to supernovae, Type 1A supernovas are not standard candles. Also photons can lose energy over cosmic distances, so the ones further away are naturally dimmer.
Firstly, you deny my offer of talking to you about my work. And then complain you've not seen my work? Despite my comment I want to talk about it with you.Learning is when you can extrapolate on what you have learned. Parroting is just repeating what you have been told, like in your case.
Where did I claim to that?
Firstly, the overall curvature of the universe is an averaging factor. Local variations obviously occur due to local variations of matter. The metric which describes the space-time around the Earth is the Schwarzchild metric, but over large distances where th effects of space-time expansion and dark energy dominate, you get AdS.
Actually, if space was entirely empty of galaxies it would be perfectly AdS, because you have a negative cosmological constant with no perturbations due to material. Where there is material, you get changes which we see in the CMB. So the hole in the CMB which is a billion light years across is a better example of AdS than anything else!
So infact we have no evidence the universe is a hypersphere at all, because we don't see such phenomena in observations. So it could be, overall, flat or even open, thus not a hypersphere. Hence why the BB model isn't "It's a hypersphere". That was a claim Nick on PhysOrg kept pushing but was corrected many times.
Just like quantum field theory was a convent idea to fill the gap of electromagnetism, allowing us to make new, better, predictions and working models and then standing up to test.
A flat plane can still undergo a space-time expansion. Infact, if you look at the FRW metric, which describes an expanding universe, there's a parameter in it called K. Depending on the value of K (<1, =1 or >1 if memory serves) you end up with spherical, flat or AdS topologies for your expanding system. So there exist ways of putting all these kinds of general space-time into expansion models.
Again, this is easy to find and if you had done any research into this, you'd know it. So why don't you?
Their properties due to their distance match the predictions of expansion not 'tired light'. 'Tired light' doesn't explain the time dilation effects we also observe, which occurs in relativistic models for two reasons, the speed the IAs are moving away from us and the expansion of the space-time as their photons moved towards us. The combined contribution of these two effects are seen experimentally. Can you find me a tired light model which explained both?
Firstly, you deny my offer of talking to you about my work. And then complain you've not seen my work? Despite my comment I want to talk about it with you.
Secondly, as demonstrated many times in threads like this, you get simple things wrong, things you can find online. So when you make a claim like "The expanding universe must be a hypersphere!" and yet one of the first things any student learns about the details of expanding universe models involves it being able to be done in hyperspheres, flat space-time and open space-time if shows you haven't even learnt said material. How can our discussions go from what is known to what is unknown when you're the one who doesn't even know what is known.
Yet you comment all the information I post can be found by a 10 year old. So why haven't you found it? What was meant as an insult for me simply reflects badly on you. Have you ever made an attempt to understand the FRW metric? It's a pretty fundamental concept in inflation, mentioned many times in any cosmology lecture course or online. But you don't seem to know about some of it's basic properties. Why?
Hi Kaneda,
Do you have work published in journals?
Kaneda,
I have minimal skills in physics, maths or cosmology. One thing I am good at is assessing people, whether through the formal process of an interview, casual conversation, or examination of my writing. Not only do I depend upon this skill, but my company has placed considerable confidence in my ability to do this. While I cannot claim to have had a 100% success record, it is as close to it as makes no difference, especially when it comes to spotting bullshit artists.
You give every appearance of falling into this category. Why don't you quit while you are behind?
Because he's the embodiment of the pathological anti-science nut. He really believes that all the current accumulated results of scientific achievements printed in any textbook (or "text book" as he so ignorantly calls them) are efforts to prevent the advancement of "real" science.
Furthermore, he thinks that by taking his huge leaps into absurd 'scientific' regions that he is displaying some sort of high-powered thinking. While actually, all it does is reveal just how terribly bad his own ignorance is.
Kaneda,
I have minimal skills in physics, maths or cosmology. One thing I am good at is assessing people, whether through the formal process of an interview, casual conversation, or examination of my writing. Not only do I depend upon this skill, but my company has placed considerable confidence in my ability to do this. While I cannot claim to have had a 100% success record, it is as close to it as makes no difference, especially when it comes to spotting bullshit artists.
You give every appearance of falling into this category. Why don't you quit while you are behind?
Well it seems like you have a lot to say to the scientific community. If you were confident in your findings, then the best thing to do would be to approach a reputable journal and have your arguments published. If not for yourself, you should do it for the advancement of science.No. Why should I bother?