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Talk:Poincaré group

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product here is a very elegant one, although it needs the action of the Lorentz-group on Minkowski-space; but since this is the natural one it can be dropped). This is the most general definition - yours is a very special realization of its Lie algebra in terms of partial derivatives. The Lorentz group is definied as the invariance group of a Minkowski-form. Please don't speak of generators - this is a kind of unmathematical jargon. The elements of the Lie algebras are best named „elements of the Lie algebra". In this connection there should be added a remark whether the Lorentz group is exponential, that is - given by exp(element of the Poincare Lie algebra) - or whether it is only generated by such elements. Who knows a proof of this or can give a reference? Moreover, there is no need to introduce a basis of the underlying Minkowski-space. Everything can be represented in a basis-free way, including the commutation relations of the pseudo-orthogonal Lie algebras, given in this old-fashioned index notation below. Even the Killing form of these Lie algebras can be written down elegantly, only in terms of the Minkowski-form. So the only structures involved is the 4-dimensional real Minkowski-space and its Minkowski-form, say <,: -->
1046:{A,B} may be treated as the Lie bracket in the form that Mathematicians like to think of it in terms of, while the former - when thought of as a commutator in the context of quantum-theoretic settings - provides an algebraic representation of {A,B} that is historically closer in line to how Physicists first encountered them. Strictly speaking, the mathematical form, which is tied to Poisson manifolds and symplectic geometry provides the correct notational language and framework for Lie algebras, since it is paradigm-neutral: it arises in both classical and quantum settings, as well as hybrids thereof (e.g. quantum theories with superselection), while the Physicists' language only applies within the quantum setting, obscures the connection to the classical limit and to classical physics and is already derivable from the Poisson manifold / symplectic formulation as an algebraic representation. I tend to use the curly brackets for the version without the i's, e.g. {Y,Z} = X, {Z,X} = Y, {X,Y} = Z for SO(3) in the context of symplectic geometry, co-adjoint orbit methodology, Poisson manifolds, while using the square brackets for applications in quantum theory = iħX, = iħY, = iħZ, to distinguish between the two. 101: 445:. And please don't use for Minkowski-space an ℜ, because even those of physics are not all of that type: The Pauli-matrices together with the identity, the four Dirac-matrices and the four Duffin-Kemmer-matrices are not of that type, but are Minkowski-spaces with respect to the canonical bilinear form trace(AB)-trace(A)trace(B) on square matrices. Exactly because of this, Dirac's linearization of the Klein-Gordon equation works, giving rise to a Clifford algebra on Minkowski-space. So its for physical reasons to work with a general Minkowski-space. 1027:, 4d ones in that article--while the unitary irreps of the non-compact Lorentz are infinite-dimensional, a bit of a mathematical curiosity when it comes to physics. Familiar with this fact of life, the majority of physicists opt for hermitean operators and are normally mindful of the i's in all redefinitions that occur, or which there are many and treacherous. If you had useful explanatory phrases to protect readers unfamiliar with this dual thinking, they could be quite welcome. But, in either language, sooner or later, the i's are unavoidable. 219: 209: 188: 31: 91: 64: 862:: it is a mixture of non-elementary facts (such as preserving only proper times is sufficient for preserving other structure), unclear statements (see above), misleading internal links (see above), and bizarre wording and metaphors (such as “the contents of spacetime could be shifted”). If two editors defend this version against my (radical) proposal, then specific issues I addressed should be considered. 561:. For example, if everything was postponed by two hours including two events and the path you took to go from one to the other, then the time interval between the events recorded by a stop-watch you carried with you would be the same. Or if everything was shifted five miles to the west, you would also see no change in the interval. It turns out that the length of a rod is also unaffected by such a shift. 22: 765:
In the latter sense, it doesn't seem to be an abuse of terminology at all, but if one is believing the wlinks, then yes, it is. I think using "preserves the interval" and explaining that the interval is "like distance" is a good introductory explanation, but I like the "preserves the metric" explanation in the technical part. In any case, we should use a little care when writing "isometry".
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Reviews of Modern Physics 21(3) July 1949, both use the Mathematician's form of the Lie bracket, without the i's; as do more recent papers, like "Newtonian Gravity and the Bargmann Algebra", Andringa et al. arXiv:101145v3 25 May 2011, just to pick something out of arXiv at random (all of them having presentations of the Poincaré Lie algebra in them).
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relates to a distance function; the fact that it is not a metric in the normal sense of that word does not change the definition of isometry. I agree that suitable terminology is important, and the terms you mention are good (we should use them where the weaker terms are used), but I do not see that this changes the validity of the term "isometry". —
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It does have the underlying structure that defines a distance measure: the (indefinite) quadratic form, which is the Minkowski squared interval to which you refer. From a group theory perspective, this is on exactly equal footing with the Euclidean metric of the Euclidean group. The term "isometry"
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That sentence seems wrong to me too. As I understand, affine transformations are a more general set of transformation which do not conserve distances. As such, the Poincare group can't be the group of affine transformations. Of course, I am not an expert on the subject, so I can certainly be wrong on
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that could take this "explanation", and not this one--it's got enough asides and loopy non-sequiturs to make it far less useful to the novice than it could be. I suspect this article could benefit from a minimal statement on the contractive origin of the Galilean group, if it has to be brought up at
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Both conventions are - and have long been - in widespread use, even in the Physics community; e.g. Currie, Jordan & Sudarshan, "Relativistic Invariance and Hamiltonian Theories of Interacting Particles", in Reviews of Modern Physics 35(2) April 1963; or Dirac "Forms of Relativistic Dynamics", in
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interested in this group... It is only discussed for its central importance in describing, indeed, governing, the real world. A working physicist cannot live without it. So, then, much of this article is a service introduction for mostly physics students. Many of these generators and their physical
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Secondly, I think I see the problem with using "isometries" but I have to ask this question to make sure. While the WP isometry article says such a transformation "preserves distances", I'm also aware of a extended use of "isometry" relative to a bilinear form meaning "preserves the bilinear form".
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you will see that it doesn't make sense to use this term without the underlying structure. In physics literature, phrases like "Minkowski metric" or "metric tensor" are used frequently, but more mathematically aware authors prefer "Minkowski squared interval" and pseudo-Riemannian geometry to show
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Also the physicists are correct and the mathematicians are wrong here. The original source of the concept of a metric is the physical measurements in Euclidean geometry (a spatial slice of Minkowsky space) using a compass and straight edge or ruler. Thus what was originally being measured was the
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the division of this article into Basic explanation and Technical explanation is appropriate. Since the Galilean group is an intuitive concept, unstated for centuries until the electromagnetic revolution, mentioning it in the Basic section is also appropriate. The contraction group concept is not
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The best way to think of this is to treat /iħ as {A,B}, which - itself - is the Lie bracket of a Lie algebra; and also the Poisson bracket of a Poisson algebra (namely: that which arises from the double-dual of the Lie algebra, which is closely tied to the co-adjoint orbit framework). The latter
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Please don't do this. The Poincare group is the semidirect product (its Lie algebra the semidirect sum) of the homogeneous Lorentz group × the Translation group of Minkowski-space. This means, it is represented by a split short exact sequence of these two groups (the notation for the semi-direct
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I've taken logic up through completeness and compactness (but not group theory), and am familiar with the Poincare (and especially the Riemann) models of hyperbolic spaces. And though I know what a group is, I came here to understand the the Poincare group because it's so important in general
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Maybe there should be a kind of simple infobox template for listing generators of a Lie algebra? I'd like to eventually modify existing articles to explain at an undergraduate level why thinking of a vector field as a linear first order differential operator with nonconstant coefficients is to
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may already be a big improvement. Looking at these articles it seems that "metric" is common, and when done very carefully, with the right links and necessary explanation, can be used without problems. "Isometry" could then be defined as a map preserving this metric, to provide a shorthand for
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Before you put up your elitist force-field shields of "no stupid people need apply", remember that Einstein said "if you can't explain it to your grandmother, you don't understand it yourself". Feynman was particularly good at this, and being in lovw with him, I try to do that too.
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is unambiguous (intuitively the same as a plane in a Euclidean space, but the concept of length changes, so not a Euclidean space). I don't particularly see how this could be made clearer, since the explanation of these concepts belongs in the respective articles, not here.
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If you ignore the effects of gravity, then there are ten basic ways of doing such shifts: translation through time, translation through any of the three dimensions of space, rotation (by a fixed angle) around any of the three spatial axes, or a
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in any of the three spatial directions. 10=1+3+3+3. If you combine such isometries together (do one and then the other), the result is also such an isometry (although not generally one of the ten basic ones). These isometries form a
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The Poincare algebra is a REAL Lie algebra, why is everybody nowadays writing the commutators with the imaginary unit? This drives me crazy! There is no $ i$ in the category of real Lie algebras. So please get rid of this!
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I am currently trying to improve the articles on Lorentz group and Möbius group, and will probably have some related suggestions for this one. To name just one: why not list ten generators of the Lie algebra, in the form
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I agree that one could formulate it more elegantly, but what is meant (according to my knowledge) is that for fermions you need either the projective representations or the representations of the Spin group (here
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I have not yet found a math or science topic I couldn't make understandable to non-Jedi. For example, my explanation of tensors that my grandmother could understand (if the horrible woman wasn't in hell now).
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These articles which Patrick has been changing are primarily for physicists. Physicists use the terms "metric" and "isometry". So Patrick is making the articles less readable and inconsistent with the sources.
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Was this an improvement or a degradation? One can use whatever terms, even “isometry”, but one has to define the quantity it should conserve: vector magnitude? dot product? metric tensor in the sense of a
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Firstly, this being a mathematical topic used by physicists, that intro should definitely be able to incorporate both disciplines. The intro right now is really short: we can probably have both and remain
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they understand something is at stake in the terminology. Though "usage" is important for terminology, as a general reference work spanning all specialties, accuracy has been a standard too.
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Thanks for the suggestion. I just copied it into the article as the new section "Simple explanation" ahead of the previous material which I renamed the "Technical explanation" section.
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does not appear to say that the distance (or squared distance) being preserved is positive (or even non-negative). If you see that in it, please indicate exactly where it says that.
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in the generators to make them antihermitean can only unleash untold grief, which has done its unwholesome damage in the past, and has been deprecated by decades-old consensus.
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Since I did not attempt any basic explanation, your reading of the previous comment was unsatisfactory. The point was that preserving the semi-Riemannian metric does
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is a physical observable). Νοw, the unitary irreps of the associated compact su(2)×su(2) are finite dimensional, but they correspond to nonunitary irreps of the
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the term 'hermitian' is not even defined in the category of real Lie algebras. I think one should not put common pysical practice over mathematical rigor...
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I also find the term strange (but that means nothing: I'm a layman) and would have preferred something like "limiting group". However, in the sentence "In
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seem like a basic explanation. Appealing to distance or pseudo-distance seems better. Let me know if you have any more questions about what I meant.
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relativity. But I still don't know what it is or how it is used, because this obscure concept is described in terms of other obscure concepts.
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It is not a metric, and I would not call it a distance either. It is confusing to use the same term for something with essential differences. -
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by Cuzkatzimhut did not seem out of place. This is not technical, nor the fact that there is a name given to this relationship. I disagree with
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actions discussed here are normally understood as hermitian matrices representing the generators on finite dimensional spaces (You may notice
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These groups and algebras are of principal interest in physics. Physicists untilize hermitean operators whose exponentials are unitary ones
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is the double cover). This section needs a cleanup, and more importantly we need to decide which group we call the Poincaré group:
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named explicitly the thing to be conserved: the interval between events (or, the same, the pseudo-Euclidean magnitude of a vector);
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links to this article, so what is a Poincaré algebra? Is it the Lie algebra of the Poincaré group? This needs to be made clear. -
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clarified that preserving (up to sign) of proper time is an equivalent, but not the basic formulation (does anybody oppose?);
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Which "plane"? A Euclidian plane in a Euclidian space?? Does it hold when reflected through a sphere in a Spherical space?
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Yes, that sentence does not make sense to me either, but I have not worked with affine groups so I am not entirely sure.
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is correct, and is the more general term. In a group-theoretic article, the use of the general term is appropriate. —
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Coordinate transformations are not quite what is being referred to here; the concept is a coordinate-independent one.
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clarified that the time can be reversed (which all physical reasoning about stop-watches apparently contradict to);
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A Lorentz transformation is an example of an isometry in the precise sense that it preserves a distance function.
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The Lorentz group is the subgroup of the Poincaré group which does not move the origin of the Minkowski space.
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elementary, requiring introduction of limits, so mentioning it is appropriate to the Technical section.
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See e.g. Blagoje Oblak - BMS Particles in Three Dimensions, p. 80, who introduces the former as the
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Why isn't this explanation in the actual page? Much more useful to people just needing background.
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on Knowledge. If you would like to participate, please visit the project page, where you can join
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on Knowledge. If you would like to participate, please visit the project page, where you can join
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clarified that vectors of all three types are preserved, and explained what it means in details;
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needs a citation. My understanding is that you can take the symmetry group of spacetime to be
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The main problem with 2012 versions of the article is that it used such terms (and links) as “
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is. It is a way in which the contents of spacetime could be shifted that would not affect the
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isometry means invariance of distance; in this case the precise term is Lorentz invariance
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Can one of you wizards explain the poincare group in a way that Feynman would approve of?
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very thing which the physicist are talking about — the metric of Minkowsky space (or of
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reflection through a plane (three degrees, the freedom in orientation of this plane);
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article. Either this "affine group of …" is a deeply substandard term, or we miss a
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The article does not properly distinguish between the three groups in section
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in the other (big conceptual change). Reference for this is Weinberg, vol I.
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the Lorentz group or its cover. There is a price to pay with either choice.
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The sentence starts with "In Minkowski space ". in this context, the term
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at the WPM talk page. The goal is to feel out what we can adopt from
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at the bottom of section 1, and deleted my explanation that it is a
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may be chosen to make the limit of the representations prettier.
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ever ascend above its doomed starter status. The Galilean group is
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in the broader meaning) may also be in use. Perhaps the article
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section. I suspect that many readers will never have heard of
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world lines, not, say, only actual world lines of particles;
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Thanks for bringing this article back to a tolerable form.
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and what the objections are. Here's what occurred to me:
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2012 versions of basic explanation were unsatisfactory.
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needs to be updated, not the link to it avoided here. —
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Knowledge level-5 vital articles in Physical sciences
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is a double cover of the zero-connected component of
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clarified that proper time can be calculated along a
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This wording does not match to the definition in the
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are not able to describe fields with spin 1/2, i.e.
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But I'm through. 428: 378: 331: 1543:Symmetry (physics)#Conservation laws and symmetry 916:to support your claim if you change the article. 543:The main thing you need to understand is what an 1219:is a comparable 10-parameter group that acts on 2799:Start-Class physics articles of High-importance 2784:Start-Class vital articles in Physical sciences 1840:is more important, because representations of 429:{\displaystyle -y\partial _{x}+x\partial _{y}} 2769:Knowledge vital articles in Physical sciences 2176:can be lifted to "normal" representations of 379:{\displaystyle x\partial _{t}+t\partial _{x}} 8: 1193:(by that name) before; certainly I had not. 1181:Perhaps it would be more appropriate in the 578:. The name of this particular group is the " 19: 1773:the universal cover of the Poincaré group 1075:Group contraction requires explanation???? 1053: 182: 58: 2692: 2684: 2668: 2640: 2629: 2626: 2591: 2576: 2546: 2544: 2500: 2498: 2463: 2461: 2425: 2417: 2414: 2370: 2368: 2325: 2317: 2314: 2276: 2274: 2239: 2237: 2183: 2181: 2143: 2141: 2097: 2071: 2069: 2015: 2013: 1975: 1973: 1929: 1891: 1889: 1847: 1845: 1803: 1788: 1783: 1780: 420: 404: 392: 370: 354: 345: 323: 317: 2136:). As the projective representations of 805:only, and that we have to consider all 484:Yes it is. I've made this explicit. -- 184: 60: 2449:{\displaystyle \mathrm {SO} _{0}(1,3)} 2349:{\displaystyle \mathrm {SO} _{0}(1,3)} 7: 2402:{\displaystyle \mathrm {Spin} (1,3)} 1183:Poincaré group#Technical explanation 1060:2603:6000:AA4D:C5B8:0:3361:EAF8:97B7 742:Discussion of early April 2013 edits 230:This article is within the scope of 112:This article is within the scope of 2529:{\displaystyle \mathrm {Pin} (1,3)} 1161:I believe it is the article on the 746:This post is meant to pick up from 49:It is of interest to the following 2774:Start-Class level-5 vital articles 2688: 2685: 2636: 2633: 2630: 2592: 2550: 2547: 2507: 2504: 2501: 2464: 2421: 2418: 2380: 2377: 2374: 2371: 2321: 2318: 2302:{\displaystyle \mathrm {SO} (1,3)} 2280: 2277: 2240: 2209:{\displaystyle \mathrm {SL} (2,C)} 2187: 2184: 2169:{\displaystyle \mathrm {SO} (3,1)} 2147: 2144: 2107: 2104: 2101: 2098: 2075: 2072: 2041:{\displaystyle \mathrm {SL} (2,C)} 2019: 2016: 2001:{\displaystyle \mathrm {SO} (3,1)} 1979: 1976: 1917:{\displaystyle \mathrm {SL} (2,C)} 1895: 1892: 1873:{\displaystyle \mathrm {SO} (1,3)} 1851: 1848: 1807: 1804: 1480:Metric tensor (general relativity) 858:I am completely dissatisfied with 417: 401: 367: 351: 320: 297:Sure, but keep the article called 14: 2819:Mid-priority mathematics articles 2486:{\displaystyle \mathrm {O} (1,3)} 2262:{\displaystyle \mathrm {O} (1,3)} 1437:", with this link to the article 700:) 19.00, 29 August 2012 (GMT+1) 582:". I hope that clears things up. 250:Knowledge:WikiProject Mathematics 2814:Start-Class mathematics articles 2794:High-importance physics articles 2764:Knowledge level-5 vital articles 1784: 1761:Citation needed for new addition 1187:Poincaré group#Basic explanation 715: 253:Template:WikiProject Mathematics 217: 207: 186: 99: 89: 62: 29: 20: 2804:Start-Class relativity articles 1968:in one case and the tossing of 1279:Lorentz invariance vs. isometry 882:Whats with this imaginary unit? 860:JRSpriggs’s “basic explanation” 822:? The same about “trajectory”: 270:This article has been rated as 152:This article has been rated as 2710: 2698: 2658: 2646: 2608: 2596: 2566: 2554: 2523: 2511: 2480: 2468: 2443: 2431: 2396: 2384: 2343: 2331: 2296: 2284: 2256: 2244: 2203: 2191: 2163: 2151: 2123: 2111: 2091: 2079: 2035: 2023: 1995: 1983: 1956:matrices with unit determinant 1943: 1931: 1911: 1899: 1867: 1855: 1823: 1811: 1539:Isometry (Riemannian geometry) 1: 2745:18:51, 12 November 2017 (UTC) 2361:Poincaré_group#Poincaré_group 2226:18:37, 12 November 2017 (UTC) 1313:17:56, 28 February 2015 (UTC) 1146:is a c-number, a function of 1037:19:36, 27 November 2013 (UTC) 995:17:50, 27 November 2013 (UTC) 974:16:13, 27 November 2013 (UTC) 943:16:17, 26 November 2013 (UTC) 903:12:49, 26 November 2013 (UTC) 332:{\displaystyle \partial _{t}} 293:Generators of the Lie algebra 244:and see a list of open tasks. 167:This article is supported by 132:Knowledge:WikiProject Physics 126:and see a list of open tasks. 2789:Start-Class physics 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1368:11:30, 1 March 2015 (UTC) 1354:07:12, 1 March 2015 (UTC) 1344:02:12, 1 March 2015 (UTC) 685:13:19, 3 April 2012 (UTC) 667:12:55, 3 April 2012 (UTC) 592:18:42, 31 July 2011 (UTC) 269: 202: 170:the relativity task force 166: 151: 84: 57: 2733:connected Poincaré group 1269:22:02, 24 May 2014 (UTC) 1242:13:43, 22 May 2014 (UTC) 1203:05:11, 22 May 2014 (UTC) 1176:00:37, 22 May 2014 (UTC) 301:and merge material from 276:project's priority scale 1638:Metric_space#Definition 1221:absolute time and space 1082:added and aside on the 1004:Agreed, but...there is 489:04:47, 8 May 2006 (UTC) 479:03:48, 8 May 2006 (UTC) 233:WikiProject Mathematics 2731:and the latter as the 2717: 2615: 2530: 2487: 2450: 2403: 2350: 2303: 2263: 2210: 2170: 2130: 2042: 2002: 1950: 1918: 1874: 1830: 1422:The article said "The 430: 380: 333: 2718: 2616: 2531: 2488: 2451: 2404: 2351: 2304: 2264: 2211: 2171: 2131: 2043: 2003: 1951: 1919: 1875: 1831: 431: 381: 334: 36:level-5 vital article 2625: 2543: 2497: 2460: 2413: 2367: 2313: 2273: 2236: 2180: 2140: 2068: 2012: 1972: 1928: 1888: 1844: 1779: 1771:quantum field theory 1521:At least the terms " 1008:nonrigorous about a 952:the inclusion of an 391: 344: 316: 256:mathematics articles 2809:Relativity articles 1432:Minkowski spacetime 1090:of the Poincaré as 820:Riemannian manifold 115:WikiProject Physics 2713: 2611: 2526: 2483: 2446: 2399: 2346: 2299: 2259: 2206: 2166: 2126: 2038: 1998: 1946: 1914: 1870: 1826: 1545:seems to refer to 426: 376: 329: 225:Mathematics portal 45:content assessment 1765:The new addition 1451:pseudo-semimetric 1321:is correct since 1319:Lorentz invariant 1286:this edit comment 1225:group contraction 1213:classical physics 1191:group contraction 1096:group contraction 1088:group contraction 1070: 1058:comment added by 985:comment added by 914:secondary sources 893:comment added by 602:comment added by 539: 525:comment added by 451:comment added by 303:Poincaré symmetry 290: 289: 286: 285: 282: 281: 181: 180: 177: 176: 2826: 2722: 2720: 2719: 2714: 2697: 2696: 2691: 2679: 2678: 2645: 2644: 2639: 2620: 2618: 2617: 2612: 2595: 2587: 2586: 2553: 2535: 2533: 2532: 2527: 2510: 2492: 2490: 2489: 2484: 2467: 2455: 2453: 2452: 2447: 2430: 2429: 2424: 2408: 2406: 2405: 2400: 2383: 2355: 2353: 2352: 2347: 2330: 2329: 2324: 2308: 2306: 2305: 2300: 2283: 2268: 2266: 2265: 2260: 2243: 2215: 2213: 2212: 2207: 2190: 2175: 2173: 2172: 2167: 2150: 2135: 2133: 2132: 2127: 2110: 2078: 2047: 2045: 2044: 2039: 2022: 2007: 2005: 2004: 1999: 1982: 1955: 1953: 1952: 1947: 1923: 1921: 1920: 1915: 1898: 1879: 1877: 1876: 1871: 1854: 1835: 1833: 1832: 1827: 1810: 1799: 1798: 1787: 1527:orthogonal group 1288: 997: 905: 725: 719: 718: 710: 614: 538: 519: 472:Poincaré algebra 467:Poincaré algebra 463: 435: 433: 432: 427: 425: 424: 409: 408: 385: 383: 382: 377: 375: 374: 359: 358: 338: 336: 335: 330: 328: 327: 258: 257: 254: 251: 248: 227: 222: 221: 211: 204: 203: 198: 190: 183: 140: 139: 138:physics articles 136: 133: 130: 109: 104: 103: 93: 86: 85: 80: 77: 66: 59: 42: 33: 32: 25: 24: 16: 2834: 2833: 2829: 2828: 2827: 2825: 2824: 2823: 2749: 2748: 2683: 2664: 2628: 2623: 2622: 2572: 2541: 2540: 2495: 2494: 2458: 2457: 2416: 2411: 2410: 2365: 2364: 2363:. For example, 2357: 2316: 2311: 2310: 2271: 2270: 2234: 2233: 2178: 2177: 2138: 2137: 2066: 2065: 2010: 2009: 1970: 1969: 1926: 1925: 1886: 1885: 1842: 1841: 1782: 1777: 1776: 1763: 1720: 1636:, for that see 1304:Thus, the term 1284: 1281: 1077: 980: 939: 888: 884: 744: 716: 714: 701: 647: 597: 576:associative law 520: 497: 469: 446: 416: 400: 389: 388: 366: 350: 342: 341: 319: 314: 313: 305:with this one. 295: 255: 252: 249: 246: 245: 223: 216: 196: 154:High-importance 137: 134: 131: 128: 127: 105: 98: 79:High‑importance 78: 72: 43:on Knowledge's 40: 30: 12: 11: 5: 2832: 2830: 2822: 2821: 2816: 2811: 2806: 2801: 2796: 2791: 2786: 2781: 2776: 2771: 2766: 2761: 2751: 2750: 2725: 2724: 2712: 2709: 2706: 2703: 2700: 2695: 2690: 2687: 2682: 2677: 2674: 2671: 2667: 2663: 2660: 2657: 2654: 2651: 2648: 2643: 2638: 2635: 2632: 2610: 2607: 2604: 2601: 2598: 2594: 2590: 2585: 2582: 2579: 2575: 2571: 2568: 2565: 2562: 2559: 2556: 2552: 2549: 2525: 2522: 2519: 2516: 2513: 2509: 2506: 2503: 2482: 2479: 2476: 2473: 2470: 2466: 2445: 2442: 2439: 2436: 2433: 2428: 2423: 2420: 2398: 2395: 2392: 2389: 2386: 2382: 2379: 2376: 2373: 2356: 2345: 2342: 2339: 2336: 2333: 2328: 2323: 2320: 2298: 2295: 2292: 2289: 2286: 2282: 2279: 2258: 2255: 2252: 2249: 2246: 2242: 2230: 2229: 2228: 2205: 2202: 2199: 2196: 2193: 2189: 2186: 2165: 2162: 2159: 2156: 2153: 2149: 2146: 2125: 2122: 2119: 2116: 2113: 2109: 2106: 2103: 2100: 2096: 2093: 2090: 2087: 2084: 2081: 2077: 2074: 2037: 2034: 2031: 2028: 2025: 2021: 2018: 1997: 1994: 1991: 1988: 1985: 1981: 1978: 1958: 1957: 1945: 1942: 1939: 1936: 1933: 1913: 1910: 1907: 1904: 1901: 1897: 1894: 1869: 1866: 1863: 1860: 1857: 1853: 1850: 1838: 1837: 1836: 1825: 1822: 1819: 1816: 1813: 1809: 1806: 1802: 1797: 1794: 1791: 1786: 1762: 1759: 1758: 1757: 1727: 1725: 1719: 1718:Which "plane"? 1716: 1715: 1714: 1713: 1712: 1711: 1710: 1709: 1708: 1707: 1706: 1705: 1704: 1703: 1702: 1701: 1700: 1699: 1698: 1667: 1666: 1665: 1664: 1663: 1662: 1661: 1660: 1659: 1658: 1657: 1656: 1655: 1654: 1653: 1652: 1615: 1614: 1613: 1612: 1611: 1610: 1609: 1608: 1607: 1606: 1605: 1604: 1603: 1602: 1571: 1570: 1569: 1568: 1567: 1566: 1565: 1564: 1563: 1562: 1561: 1560: 1508: 1507: 1506: 1505: 1504: 1503: 1502: 1501: 1500: 1499: 1463: 1462: 1461: 1460: 1459: 1458: 1457: 1456: 1455: 1454: 1424:Poincaré group 1411: 1410: 1409: 1408: 1407: 1406: 1405: 1404: 1385: 1375: 1374: 1373: 1372: 1371: 1370: 1329:. If you read 1302: 1301: 1298: 1280: 1277: 1276: 1275: 1274: 1273: 1272: 1271: 1247: 1246: 1245: 1244: 1217:Galilean group 1206: 1205: 1163:Galilean group 1108:Galilean group 1084:Galilean group 1076: 1073: 1072: 1071: 1048: 1047: 1042: 1041: 1040: 1039: 999: 998: 946: 945: 937: 883: 880: 879: 878: 877: 876: 875: 874: 815: 814: 813: 810: 799: 796: 793: 778: 777: 761: 760: 743: 740: 739: 738: 711: 706:comment added 688: 687: 673: 646: 643: 642: 641: 640: 639: 638: 637: 618: 617: 616: 615: 604:24.218.104.144 580:Poincaré group 562: 527:Helvitica Bold 496: 493: 492: 491: 468: 465: 453:130.133.155.68 437: 436: 423: 419: 415: 412: 407: 403: 399: 396: 386: 373: 369: 365: 362: 357: 353: 349: 339: 326: 322: 299:Poincaré group 294: 291: 288: 287: 284: 283: 280: 279: 268: 262: 261: 259: 242:the discussion 229: 228: 212: 200: 199: 191: 179: 178: 175: 174: 165: 162: 161: 150: 144: 143: 141: 124:the discussion 111: 110: 107:Physics portal 94: 82: 81: 67: 55: 54: 48: 26: 13: 10: 9: 6: 4: 3: 2: 2831: 2820: 2817: 2815: 2812: 2810: 2807: 2805: 2802: 2800: 2797: 2795: 2792: 2790: 2787: 2785: 2782: 2780: 2777: 2775: 2772: 2770: 2767: 2765: 2762: 2760: 2757: 2756: 2754: 2747: 2746: 2742: 2738: 2734: 2730: 2729:Poncaré group 2707: 2704: 2701: 2693: 2680: 2675: 2672: 2669: 2665: 2661: 2655: 2652: 2649: 2641: 2605: 2602: 2599: 2588: 2583: 2580: 2577: 2573: 2569: 2563: 2560: 2557: 2539: 2538: 2537: 2520: 2517: 2514: 2477: 2474: 2471: 2440: 2437: 2434: 2426: 2393: 2390: 2387: 2362: 2340: 2337: 2334: 2326: 2293: 2290: 2287: 2253: 2250: 2247: 2227: 2223: 2219: 2200: 2197: 2194: 2160: 2157: 2154: 2120: 2117: 2114: 2094: 2088: 2085: 2082: 2062: 2061: 2060: 2059: 2055: 2051: 2032: 2029: 2026: 1992: 1989: 1986: 1967: 1963: 1940: 1937: 1934: 1908: 1905: 1902: 1883: 1864: 1861: 1858: 1839: 1820: 1817: 1814: 1800: 1795: 1792: 1789: 1775: 1774: 1772: 1768: 1767: 1766: 1760: 1756: 1753: 1748: 1744: 1743: 1742: 1741: 1737: 1733: 1732:216.52.207.72 1728: 1724: 1717: 1697: 1693: 1689: 1685: 1684: 1683: 1682: 1681: 1680: 1679: 1678: 1677: 1676: 1675: 1674: 1673: 1672: 1671: 1670: 1669: 1668: 1651: 1647: 1643: 1639: 1635: 1632:It refers to 1631: 1630: 1629: 1628: 1627: 1626: 1625: 1624: 1623: 1622: 1621: 1620: 1619: 1618: 1617: 1616: 1601: 1597: 1593: 1589: 1585: 1584: 1583: 1582: 1581: 1580: 1579: 1578: 1577: 1576: 1575: 1574: 1573: 1572: 1559: 1556: 1552: 1548: 1544: 1540: 1536: 1532: 1528: 1524: 1523:orthogonality 1520: 1519: 1518: 1517: 1516: 1515: 1514: 1513: 1512: 1511: 1510: 1509: 1498: 1494: 1490: 1485: 1481: 1477: 1476:Metric tensor 1473: 1472: 1471: 1470: 1469: 1468: 1467: 1466: 1465: 1464: 1452: 1448: 1444: 1440: 1436: 1433: 1429: 1425: 1421: 1420: 1419: 1418: 1417: 1416: 1415: 1414: 1413: 1412: 1403: 1399: 1395: 1391: 1386: 1383: 1382: 1381: 1380: 1379: 1378: 1377: 1376: 1369: 1365: 1361: 1357: 1356: 1355: 1352: 1347: 1346: 1345: 1341: 1337: 1332: 1328: 1324: 1320: 1317: 1316: 1315: 1314: 1311: 1307: 1299: 1296: 1295: 1294: 1292: 1287: 1278: 1270: 1266: 1262: 1257: 1254:According to 1253: 1252: 1251: 1250: 1249: 1248: 1243: 1240: 1239: 1234: 1230: 1226: 1222: 1218: 1214: 1210: 1209: 1208: 1207: 1204: 1200: 1196: 1192: 1188: 1184: 1180: 1179: 1178: 1177: 1173: 1169: 1164: 1159: 1157: 1153: 1150:diverging as 1149: 1145: 1141: 1137: 1133: 1129: 1125: 1121: 1117: 1113: 1109: 1105: 1101: 1097: 1093: 1089: 1085: 1081: 1080:User:‎Rgdboer 1074: 1069: 1065: 1061: 1057: 1050: 1049: 1044: 1043: 1038: 1034: 1030: 1026: 1025:Lorentz group 1022: 1021: 1015: 1011: 1007: 1003: 1002: 1001: 1000: 996: 992: 988: 987:94.223.151.28 984: 978: 977: 976: 975: 971: 967: 963: 959: 955: 951: 944: 941: 940: 933: 931: 928: 924: 923: 922: 915: 912: 908: 907: 906: 904: 900: 896: 895:178.12.206.11 892: 881: 873: 869: 865: 861: 857: 856: 855: 851: 847: 843: 839: 838: 837: 833: 829: 825: 821: 816: 811: 808: 804: 800: 797: 794: 791: 790: 788: 784: 780: 779: 776: 772: 768: 763: 762: 757: 756: 755: 753: 749: 741: 737: 733: 729: 726:the wording. 724: 723: 712: 709: 705: 699: 695: 690: 689: 686: 682: 678: 674: 671: 670: 669: 668: 664: 660: 656: 652: 644: 636: 632: 628: 624: 623: 622: 621: 620: 619: 613: 609: 605: 601: 595: 594: 593: 589: 585: 581: 577: 573: 568: 563: 560: 556: 552: 548: 547: 542: 541: 540: 536: 532: 528: 524: 517: 514: 509: 505: 501: 494: 490: 487: 483: 482: 481: 480: 477: 473: 466: 464: 462: 458: 454: 450: 441: 421: 413: 410: 405: 397: 394: 387: 371: 363: 360: 355: 347: 340: 324: 312: 311: 310: 306: 304: 300: 292: 277: 273: 267: 264: 263: 260: 243: 239: 235: 234: 226: 220: 215: 213: 210: 206: 205: 201: 195: 192: 189: 185: 172: 171: 164: 163: 159: 155: 149: 146: 145: 142: 125: 121: 117: 116: 108: 102: 97: 95: 92: 88: 87: 83: 76: 71: 68: 65: 61: 56: 52: 46: 38: 37: 27: 23: 18: 17: 2732: 2728: 2726: 2358: 2008:in favor of 1961: 1959: 1764: 1746: 1729: 1722: 1721: 1634:Metric space 1586:The article 1546: 1530: 1446: 1443:pseudometric 1442: 1423: 1327:metric space 1318: 1305: 1303: 1290: 1283:Relating to 1282: 1237: 1168:Cuzkatzimhut 1160: 1155: 1151: 1147: 1143: 1139: 1135: 1131: 1127: 1123: 1119: 1115: 1111: 1103: 1099: 1091: 1078: 1054:— Preceding 1029:Cuzkatzimhut 1019: 1018: 1013: 1009: 1005: 981:— Preceding 966:Cuzkatzimhut 961: 957: 953: 949: 947: 935: 929: 926: 920: 918: 889:— Preceding 885: 841: 823: 806: 745: 720: 651:affine group 648: 598:— Preceding 579: 544: 521:— Preceding 515: 512: 510: 506: 502: 498: 470: 447:— Preceding 442: 438: 307: 296: 272:Mid-priority 271: 231: 197:Mid‑priority 168: 153: 113: 51:WikiProjects 34: 1482:instead of 1474:Linking to 1233:this revert 864:Incnis Mrsi 828:Incnis Mrsi 752:these edits 728:Incnis Mrsi 702:—Preceding 659:Incnis Mrsi 655:dab hatnote 551:proper time 476:72.58.19.66 247:Mathematics 238:mathematics 194:Mathematics 41:Start-class 2753:Categories 1447:semimetric 1435:isometries 1256:WP:UPFRONT 1010:convention 824:Rschwieb’s 803:world line 787:trajectory 555:trajectory 75:Relativity 2456:, not of 1688:JRSpriggs 1592:JRSpriggs 1394:JRSpriggs 1325:is not a 1323:spacetime 1195:JRSpriggs 748:this note 677:JRSpriggs 627:JRSpriggs 584:JRSpriggs 513:Helvitica 39:is rated 2737:EduardoW 2218:EduardoW 1884:. 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Index


level-5 vital article
content assessment
WikiProjects
WikiProject icon
Physics
Relativity
WikiProject icon
icon
Physics portal
WikiProject Physics
Physics
the discussion
High
project's importance scale
the relativity task force
WikiProject icon
Mathematics
WikiProject icon
icon
Mathematics portal
WikiProject Mathematics
mathematics
the discussion
Mid
project's priority scale
Poincaré group
Poincaré symmetry
unsigned
130.133.155.68

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