![]() |
| If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|||||||
| Tags: absurd, claim, metric, tensor |
|
|
Thread Tools | Display Modes |
|
#1
|
|||
|
|||
|
I see that the discussion of whether the metric qualifies as a tensor
or not has splintered into many different localized groups which are very confusing. Thus, I would like to put everything into a nutshell of the pros and cons. Although the tensors can cover more ranks, the discussion should only be limited what GR covers. That is rank 2 tensors or the 4-by-4 matrices. The definition of a tensor as agreed by almost everyone says that any matrix invariant under a coordinate transformation is a tensor while the elements to the matrix can change under the same transformation. **** Pros' argument: The geometry described is invariant under any transformation. Thus, it can be represented by an operator operating on the same vector twice. ds^2 = f(dq,dq) Where ** ds^2 = the invariant geometry ** f() = the operator ** dq = the coordinate vector Of course, we all know that ds^2 = g_ij dq^i dq^j = g'_mn dq'^m dq'^n Where ** dq' = Different coordinate system The question is the matrices ([g] = [g']). **** Cons's argument: According to the pros, although the elements of the matrices (g_ij =/= g'_ij), the martrix ([g] = [g']). In doing so, they can never describe what constitutes how these 2 matrices are identical. They avoid it as if a plague in fact. They can only hand-wave it by saying over and over again that they are indeed identical. **** What is at stake? Does it matter if the metric is a tensor or not for the sake of the mathematics involved? Yes, it does. The interpretation to the infinite number of solutions to the field equations is at stake. The existence of the black holes is at stake. Apparently, the pros have never followed through the derivation of the solutions to the field equations. Each solution in terms of g_ij is only valid to the choice of coordinate system where each solution very different from the others must describe a different geometry using the same coordinate system. This means the field equations do have an infinite number of solutions in which the Schwarzschild metric, Schwarzschild's original metric, or any other is just as valid as any other where each describes a different geometry. This would shatter the general theory of relativity. The field equations in free space are R_ij(q^0, q^1, q^2, q^3) = 0 Where ** R_ij(q) = Ricci tensor as a function of q ** g1_ij(q) = Solution as function of q ** g2_ij(q) = Solution as function of q ** g3_ij(q) = Solution as function of q ** ... And all these different geometries described by each solution with the same coordinate system. ** ds1^2 = g1_ij dq^i dq^j ** ds2^2 = g2_ij dq^i dq^j ** ds3^2 = g3_ij dq^i dq^j ** ... The silly claim by the pros is that ([g1] = [g2] = [g3] = ...). Thus, (ds1^2 = ds2^2 = ds^3 = ...). They are wrong. The simple mathematics shows so. They cannot prove why ([g1] = [g2] = [g3] = ...). The Schwarzschild metric is not unique. The existence of black holes is based on a non-unique solution to the field equations. 100 years of physics is totally BS based on this wrong concept of linear algebra. |
| Ads |
|
#2
|
|||
|
|||
|
Koobee Wublee wrote: I see that the discussion of whether the metric qualifies as a tensor or not has splintered into many different localized groups which are very confusing. Thus, I would like to put everything into a nutshell of the pros and cons. Although the tensors can cover more ranks, the discussion should only be limited what GR covers. That is rank 2 tensors or the 4-by-4 matrices. The definition of a tensor as agreed by almost everyone says that any matrix invariant under a coordinate transformation is a tensor while the elements to the matrix can change under the same transformation. That isn't what a tensor is. A tensor is _NOT_ a matrix that is invariant under a coordinate transformation. Stop trying to shoehorn what you learned in linear algebra into a different subject. http://en.wikipedia.org/wiki/Tensor [...] The silly claim by the pros is that ([g1] = [g2] = [g3] = ...). Thus, (ds1^2 = ds2^2 = ds^3 = ...). They are wrong. The simple mathematics shows so. They cannot prove why ([g1] = [g2] = [g3] = ...). The Schwarzschild metric is not unique. The existence of black holes is based on a non-unique solution to the field equations. 100 years of physics is totally BS based on this wrong concept of linear algebra. Jesus christ more of this tripe. You continually make mistake after mistake because you have no training in differential geometry. Your argument is DOA because differential geometry does not obey the rules of linear algebra. All that crap you learned in there is _NOT APPLICABLE_. I repeat because it bears repeating: Nobody says that the components of the metric tensor are invariant under a coordinate transformation. Nobody says that a particular representation of the metric tensor is invariant under a coordinate transformation. I am simply amazed that you even talk about the uniqueness of the Schwarzschild solution when you admit not having even seen the proof of Birkhoff's theorem. If you want to continue 'debating', I would like to remind you that you once asserted that you could introduce curvature into a manifold through a coordinate transformation. You really do not know what you are talking about and should best study a subject before you attempt to **** all over it. |
|
#3
|
|||
|
|||
|
Koobee Wublee says...
The geometry described is invariant under any transformation. Thus, it can be represented by an operator operating on the same vector twice. ds^2 = f(dq,dq) Where ** ds^2 = the invariant geometry ** f() = the operator ** dq = the coordinate vector Of course, we all know that ds^2 = g_ij dq^i dq^j = g'_mn dq'^m dq'^n Where ** dq' = Different coordinate system The question is the matrices ([g] = [g']). According to the pros, although the elements of the matrices (g_ij =/= g'_ij), the martrix ([g] = [g']). Nobody has said that the *matrices* are the same. What they have told you is that a tensor is *not* a matrix. A tensor is a bilinear mapping on vectors and 1-forms. In doing so, they can never describe what constitutes how these 2 matrices are identical. They're *not* identical. Nobody said they were. What they said was that the *tensor* is not equal to the matrix. The tensor is not changed by changing coordinate systems, although the corresponding matrix is. They avoid it as if a plague in fact. They can only hand-wave it by saying over and over again that they are indeed identical. Nobody has said it even once. What they have told you, over and over again is that the metric is a tensor, and a tensor is independent of coordinates, and a tensor is *not* a matrix, it is a bilinear operator. -- Daryl McCullough Ithaca, NY |
|
#4
|
|||
|
|||
|
You would need 50 more IQ points to realize that you're incompetent. Koobee Wublee wrote: I see that the discussion of whether the metric qualifies as a tensor or not has splintered into many different localized groups which are very confusing. Thus, I would like to put everything into a nutshell of the pros and cons. Although the tensors can cover more ranks, the discussion should only be limited what GR covers. That is rank 2 tensors or the 4-by-4 matrices. The definition of a tensor as agreed by almost everyone says that any matrix invariant under a coordinate transformation is a tensor while the elements to the matrix can change under the same transformation. **** Pros' argument: The geometry described is invariant under any transformation. Thus, it can be represented by an operator operating on the same vector twice. ds^2 = f(dq,dq) Where ** ds^2 = the invariant geometry ** f() = the operator ** dq = the coordinate vector Of course, we all know that ds^2 = g_ij dq^i dq^j = g'_mn dq'^m dq'^n Where ** dq' = Different coordinate system The question is the matrices ([g] = [g']). **** Cons's argument: According to the pros, although the elements of the matrices (g_ij =/= g'_ij), the martrix ([g] = [g']). In doing so, they can never describe what constitutes how these 2 matrices are identical. They avoid it as if a plague in fact. They can only hand-wave it by saying over and over again that they are indeed identical. **** What is at stake? Does it matter if the metric is a tensor or not for the sake of the mathematics involved? Yes, it does. The interpretation to the infinite number of solutions to the field equations is at stake. The existence of the black holes is at stake. Apparently, the pros have never followed through the derivation of the solutions to the field equations. Each solution in terms of g_ij is only valid to the choice of coordinate system where each solution very different from the others must describe a different geometry using the same coordinate system. This means the field equations do have an infinite number of solutions in which the Schwarzschild metric, Schwarzschild's original metric, or any other is just as valid as any other where each describes a different geometry. This would shatter the general theory of relativity. The field equations in free space are R_ij(q^0, q^1, q^2, q^3) = 0 Where ** R_ij(q) = Ricci tensor as a function of q ** g1_ij(q) = Solution as function of q ** g2_ij(q) = Solution as function of q ** g3_ij(q) = Solution as function of q ** ... And all these different geometries described by each solution with the same coordinate system. ** ds1^2 = g1_ij dq^i dq^j ** ds2^2 = g2_ij dq^i dq^j ** ds3^2 = g3_ij dq^i dq^j ** ... The silly claim by the pros is that ([g1] = [g2] = [g3] = ...). Thus, (ds1^2 = ds2^2 = ds^3 = ...). They are wrong. The simple mathematics shows so. They cannot prove why ([g1] = [g2] = [g3] = ...). The Schwarzschild metric is not unique. The existence of black holes is based on a non-unique solution to the field equations. 100 years of physics is totally BS based on this wrong concept of linear algebra. |
|
#5
|
|||
|
|||
|
Koobee Wublee wrote:
The definition of a tensor as agreed by almost everyone says that any matrix invariant under a coordinate transformation is a tensor That is not the definition of tensor. Not even close. You need to LEARN about the subject before attempting to write about it. Tom Roberts |
|
#6
|
|||
|
|||
|
Koobee Wublee wrote: I see that the discussion of whether the metric qualifies as a tensor or not has splintered into many .... Actually two... ....different localized groups which are very confusing. Thus, I would like to put everything into a nutshell of the pros and cons. Although the tensors can cover more ranks, the discussion should only be limited what GR covers. That is rank 2 tensors or the 4-by-4 matrices. Do ypou know what a rank is? Do you know the difference between the type of a tensor and the rank of the tensor? The definition of a tensor as agreed by almost everyone .... This has never been demonstrated by you. In fact it would be impossible for you to do because you don't know what a tensor is. This I have gleened from the posts of yours that I've readon this newsgroup. That you refuse to refer us to a math text which would back your assertion speaks volumes to this end. ...says that any matrix invariant under a coordinate transformation is a tensor while the elements to the matrix can change under the same transformation. And here is the problem. You constantly confuse matrices with tensors. While a tensor can be *represented* by matrices in some cases (e.g. in a given coordinate system) a tensor is not a matrix. Not all matrices represent tensors either. **** Pros' argument: The geometry described is invariant under any transformation. Thus, it can be represented by an operator operating on the same vector twice. ds^2 = f(dq,dq) Where ** ds^2 = the invariant geometry ds^2 is the invariant *interval*. ** f() = the operator ** dq = the coordinate vector There is zero need for dq to be a coordinate vector at all. It may only need to be the geometric object that is the vector without any coordinate representation. Of course, we all know that ds^2 = g_ij dq^i dq^j = g'_mn dq'^m dq'^n That we agree on. Where ** dq' = Different coordinate system dq is the differential of a coordinate. The question is the matrices ([g] = [g']). That is a question brought to this newsgroup by you and for which you invented your own definition of "tensor". **** Cons's argument: According to the pros, although the elements of the matrices (g_ij =/= g'_ij), the martrix ([g] = [g']). In doing so, they can never describe what constitutes how these 2 matrices are identical. They avoid it as if a plague in fact. They can only hand-wave it by saying over and over again that they are indeed identical. If all tensors were matrices and nothing else then you might have something there. But you're wrong. Tensors and matrices are totally different things. If I give you a matrix then there it would be impossible for you to tell me if it represented a tensor. So I repeat my challenge to you - Post a reference to a math or GR textbook which uses your definition of tensor. The challenge is made. Will the challenge be accepted? Best wishes Pete |
|
#7
|
|||
|
|||
|
"Koobee Wublee" wrote in message ps.com... I see that the discussion of whether the metric qualifies as a tensor or not has splintered into many different localized groups which are very confusing. Thus, I would like to put everything into a nutshell of the pros and cons. Although the tensors can cover more ranks, the discussion should only be limited what GR covers. That is rank 2 tensors or the 4-by-4 matrices. The definition of a tensor as agreed by almost everyone says that any matrix invariant under a coordinate transformation is a tensor while the elements to the matrix can change under the same transformation. "The Absurd Claim of the Imbecile about the Metric as a Tensor": http://users.telenet.be/vdmoortel/di...surdClaim.html Dirk Vdm |
|
#8
|
|||
|
|||
|
Dirk Van de moortel wrote: "Koobee Wublee" wrote in message ps.com... I see that the discussion of whether the metric qualifies as a tensor or not has splintered into many different localized groups which are very confusing. Thus, I would like to put everything into a nutshell of the pros and cons. Although the tensors can cover more ranks, the discussion should only be limited what GR covers. That is rank 2 tensors or the 4-by-4 matrices. The definition of a tensor as agreed by almost everyone says that any matrix invariant under a coordinate transformation is a tensor while the elements to the matrix can change under the same transformation. "The Absurd Claim of the Imbecile about the Metric as a Tensor": http://users.telenet.be/vdmoortel/di...surdClaim.html You ought to consider having a separate page for classics like this one. I think that putting a gem like this amongst fumbles due to the mere willful stupidity of the standard kook doesn't do justice to the self-delusion required to write something so stupid while simultaneously believing he is the one and only disciple of Riemann. This one is just too funny. |
|
#9
|
|||
|
|||
|
"bergeron" wrote in message ups.com... Dirk Van de moortel wrote: "Koobee Wublee" wrote in message ps.com... I see that the discussion of whether the metric qualifies as a tensor or not has splintered into many different localized groups which are very confusing. Thus, I would like to put everything into a nutshell of the pros and cons. Although the tensors can cover more ranks, the discussion should only be limited what GR covers. That is rank 2 tensors or the 4-by-4 matrices. The definition of a tensor as agreed by almost everyone says that any matrix invariant under a coordinate transformation is a tensor while the elements to the matrix can change under the same transformation. "The Absurd Claim of the Imbecile about the Metric as a Tensor": http://users.telenet.be/vdmoortel/di...surdClaim.html You ought to consider having a separate page for classics like this one. I think that putting a gem like this amongst fumbles due to the mere willful stupidity of the standard kook doesn't do justice to the self-delusion required to write something so stupid while simultaneously believing he is the one and only disciple of Riemann. This one is just too funny. Paradoxically painfully funny :-| Dirk Vdm |
|
#10
|
|||
|
|||
|
"Dirk Van de moortel" wrote in message ... "bergeron" wrote in message ups.com... Dirk Van de moortel wrote: "Koobee Wublee" wrote in message ps.com... I see that the discussion of whether the metric qualifies as a tensor or not has splintered into many different localized groups which are very confusing. Thus, I would like to put everything into a nutshell of the pros and cons. Although the tensors can cover more ranks, the discussion should only be limited what GR covers. That is rank 2 tensors or the 4-by-4 matrices. The definition of a tensor as agreed by almost everyone says that any matrix invariant under a coordinate transformation is a tensor while the elements to the matrix can change under the same transformation. "The Absurd Claim of the Imbecile about the Metric as a Tensor": http://users.telenet.be/vdmoortel/di...surdClaim.html You ought to consider having a separate page for classics like this one. I think that putting a gem like this amongst fumbles due to the mere willful stupidity of the standard kook doesn't do justice to the self-delusion required to write something so stupid while simultaneously believing he is the one and only disciple of Riemann. This one is just too funny. Paradoxically painfully funny :-| Dirk Vdm Wanna know what really irks me about threads like this? Its those people who say things like "You don't understand the book you're quoting" or that "You quote books because you don't know what's in them" etc. When in fact, and Koobee is a good example, is that I almost only refer to texts when someone is claiming that something is defined other than the claim it is, as in this case. But watch Dirk. I placed a challege to post a textual source in which the authors definition is identical to his. Think he'll answer the call? I say noway Jose. He's commited himself far too greatly than to be able to admit his mistake now. On the other hand I try to always admit my mistakes, even when others have forgotten them. In fact I start threads which seem to come out of nowhere or to rehash a dead subject when actually it was to correct an error I made a while before that. Hey Dirk - I thought I was in your list of Fumbles?? Did I loose my proud position of recognition there? LOL! Pete |
| Thread Tools | |
| Display Modes | |
|
|
Similar Threads
|
||||
| Thread | Thread Starter | Forum | Replies | Last Post |
| Determining metric tensor | qmagick@yahoo.com | Current Physics Research (Moderated) | 6 | February 1st 05 08:35 PM |
| World Hologram Metric Tensor | Jack Sarfatti | The Theory of Relativity | 1 | December 29th 04 11:01 AM |
| The symmetry of the metric tensor | Amantine | The Theory of Relativity | 16 | September 20th 04 10:17 PM |
| What is the Physical Significance of the Metric Tensor of the Flat Metric? | Alex Green | Current Physics Research (Moderated) | 11 | August 14th 04 01:58 PM |
| What is the Physical Significance of the Metric Tensor of the Flat Metric? | Peter Battaglino | Current Physics Research (Moderated) | 2 | August 14th 04 01:58 PM |