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Scale invariance

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4190:, scaling transformations arise because of the perspective image mapping and because of objects having different physical size in the world. In these areas, scale invariance refers to local image descriptors or visual representations of the image data that remain invariant when the local scale in the image domain is changed. Detecting local maxima over scales of normalized derivative responses provides a general framework for obtaining scale invariance from image data. Examples of applications include 1569: 3624: 3485: 1403: 2552:
The φ theory example above demonstrates that the coupling parameters of a quantum field theory can be scale-dependent even if the corresponding classical field theory is scale-invariant (or conformally invariant). If this is the case, the classical scale (or conformal) invariance is said to be
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The key point is that the Ising model has a spin-spin interaction, making it energetically favourable for two adjacent spins to be aligned. On the other hand, thermal fluctuations typically introduce a randomness into the alignment of spins. At some critical temperature,
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Even though the microscopic physics of these two systems is completely different, their critical exponents turn out to be the same. Moreover, one can calculate these exponents using the same statistical field theory. The key observation is that at a phase transition or
2215: 3246:, fluctuations occur at all length scales, and thus one should look for a scale-invariant statistical field theory to describe the phenomena. In a sense, universality is the observation that there are relatively few such scale-invariant theories. 1840: 3217:
is seen in a large variety of physical systems. It expresses the idea that different microscopic physics can give rise to the same scaling behaviour at a phase transition. A canonical example of universality involves the following two systems:
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of the field, and its value depends on the theory under consideration. Scale invariance will typically hold provided that no fixed length scale appears in the theory. Conversely, the presence of a fixed length scale indicates that a theory is
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A consequence of scale invariance is that given a solution of a scale-invariant field equation, we can automatically find other solutions by rescaling both the coordinates and the fields appropriately. In technical terms, given a solution,
2540:, of a classical field discussed above. However, the scaling dimensions of operators in a CFT typically differ from those of the fields in the corresponding classical theory. The additional contributions appearing in the CFT are known as 1641: 1564:{\displaystyle {\begin{aligned}\nabla ^{2}\mathbf {E} ={\frac {1}{c^{2}}}{\frac {\partial ^{2}\mathbf {E} }{\partial t^{2}}}\\\nabla ^{2}\mathbf {B} ={\frac {1}{c^{2}}}{\frac {\partial ^{2}\mathbf {B} }{\partial t^{2}}}\end{aligned}}} 3277:
The formation and propagation of cracks and tears in materials ranging from steel to rock to paper. The variations of the direction of the tear, or the roughness of a fractured surface, are in power-law proportion to the size
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is the observation that widely different microscopic systems can display the same behaviour at a phase transition. Thus phase transitions in many different systems may be described by the same underlying scale-invariant
3619:{\displaystyle \rho {\frac {\partial \mathbf {u} }{\partial t}}+\rho \mathbf {u} \cdot \nabla \mathbf {u} =-\nabla P+\mu \left(\nabla ^{2}\mathbf {u} +{\frac {1}{3}}\nabla \left(\nabla \cdot \mathbf {u} \right)\right)} 4113: 3979: 3092: 1327: 4166: 1176: 2366: 771:
More precisely, scaling in stochastic systems concerns itself with the likelihood of choosing a particular configuration out of the set of all possible random configurations. This likelihood is given by the
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For a QFT to be scale-invariant, its coupling parameters must be independent of the energy-scale, and this is indicated by the vanishing of the beta-functions of the theory. Such theories are also known as
433: 3189:(SLE). As we have seen above, CFTs describe the physics of phase transitions, and so one can relate the critical exponents of certain phase transitions to these fractal dimensions. Examples include the 2 1592: 1408: 993:
qualify as exponential dispersion models and most exponential dispersion models manifest variance functions of this form. Hence many probability distributions have variance functions that express this
2723: 1248: 3932: 747: 275: 108:, scale invariance most commonly applies to the invariance of a whole theory under dilatations. Such theories typically describe classical physical processes with no characteristic length scale. 520: 2988: 31: 3170: 2557:. A classically scale-invariant field theory, where scale invariance is broken by quantum effects, provides an explication of the nearly exponential expansion of the early universe called 2239: = 4 (e.g. three spatial dimensions and one time dimension), the scalar field scaling dimension is Δ = 1. The field equation is then invariant under the transformation 2114: 4021: 3392: 3889: 2084: 1033:
is near to being a scale-invariant function. Although in mathematics this means that the spectrum is a power-law, in cosmology the term "scale-invariant" indicates that the amplitude,
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substances. This is a statistical mechanics model, which also has a description in terms of conformal field theory. The system consists of an array of lattice sites, which form a
3732:, relating the fluid pressure to the fluid density. The equation of state depends on the type of fluid and the conditions to which it is subjected. For example, we consider the 3784: 3466: 1752: 596: 2765:
are scale-invariant, and so the Ising model at this phase transition is expected to be described by a scale-invariant statistical field theory. In fact, this theory is the
134:, fluctuations occur at all length scales, and thus one should look for an explicitly scale-invariant theory to describe the phenomena. Such theories are scale-invariant 58:
is a feature of objects or laws that do not change if scales of length, energy, or other variables, are multiplied by a common factor, and thus represent a universality.
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The frequency of citations of journal articles, considered in the network of all citations amongst all papers, as a function of the number of citations in a given paper.
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For a theory to be scale-invariant, its field equations should be invariant under a rescaling of the coordinates, combined with some specified rescaling of the fields,
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Extensive discussion of scale invariance in quantum and statistical field theories, applications to critical phenomena and the epsilon expansion and related topics.
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has no coupling parameters. Therefore, like the classical version, it is scale-invariant. In the language of the renormalization group, this theory is known as the
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A simple example of a scale-invariant QFT is the quantized electromagnetic field without charged particles. This theory actually has no coupling parameters (since
2450:(which is the coupling parameter in the theory) increases with increasing energy. Therefore, while the quantized electromagnetic field without charged particles 645:. In addition, the Koch curve scales not only at the origin, but, in a certain sense, "everywhere": miniature copies of itself can be found all along the curve. 2654:
An example of the kind of physical quantities one would like to calculate at this critical temperature is the correlation between spins separated by a distance
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in piles of sand. The likelihood of an avalanche is in power-law proportion to the size of the avalanche, and avalanches are seen to occur at all size scales.
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noise. It requires, in essence, that any exponential dispersion model that asymptotically manifests a variance to mean power law will be required express a
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is the speed of sound in the fluid. Given this equation of state, Navier–Stokes and the continuity equation are invariant under the transformations
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Consider first the linear theory. Like the electromagnetic field equations above, the equation of motion for this theory is also a wave equation,
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is not scale-invariant, there do exist scale-invariant quantized scalar field theories other than the Gaussian fixed point. One example is the
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in the field equation. Such a term is often referred to as a `mass' term, and would break the invariance under the above transformation. In
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under additive and reproductive convolution as well as under scale transformation. These include a number of common distributions: the
4118: 1136: 2311: 1391: 353: 2100:, there are certain nonlinear modifications of massless scalar field theory which are also scale-invariant. One example is massless 4330:
Kendal, W. S.; Jørgensen, B. (2011). "Taylor's power law and fluctuation scaling explained by a central-limit-like convergence".
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On the other hand, in the two-dimensional case the Ising model is exactly soluble. In particular, it is equivalent to one of the
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The distribution of rocks of different sizes in an aggregate mixture that is being shaken (with gravity acting on the rocks).
2664: 119:. In a scale-invariant theory, the strength of particle interactions does not depend on the energy of the particles involved. 1208: 961:
further implies that for any sequence that exhibits a variance to mean power law under these conditions will also manifest
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the spin-spin interaction will begin to dominate, and there is some net alignment of spins in one of the two directions.
2467: 2443: 223: 4434: 4259: 2210:{\displaystyle {\frac {1}{c^{2}}}{\frac {\partial ^{2}\varphi }{\partial t^{2}}}-\nabla ^{2}\varphi +g\varphi ^{3}=0.} 1339:
We note that this condition is rather restrictive. In general, solutions even of scale-invariant field equations will
463: 4464: 4203: 2943: 4657: 3214: 3123: 141: 3987: 3358: 4647: 3855: 3243: 131: 17: 579:. Projective geometry is a particularly rich field of mathematics; in its most abstract forms, the geometry of 4275:
Eisler, Z.; Bartos, I.; Kertész, J. (2008). "Fluctuation scaling in complex systems: Taylor's law and beyond".
2045: 93:, where a function or curve is invariant under a discrete subset of the dilations. It is also possible for the 2896: 2625:, and this spin can take either the value +1 or −1. (These states are also called up and down, respectively.) 1100: 3822: 3320: 3186: 2278: 2245: 1963: 1884: 1851: 859: 4534:
Lindeberg, T. (2013) Invariance of visual operations at the level of receptive fields, PLoS ONE 8(7):e66990.
4026: 3397: 1919: 802: 62: 4652: 4642: 4584: 2541: 1030: 958: 3473: 1835:{\displaystyle {\frac {1}{c^{2}}}{\frac {\partial ^{2}\varphi }{\partial t^{2}}}-\nabla ^{2}\varphi =0,} 3745: 3469: 3434: 982: 4585:"Scale selection", Computer Vision: A Reference Guide, (K. Ikeuchi, Editor), Springer, pages 701-713. 3249:
The set of different microscopic theories described by the same scale-invariant theory is known as a
2639: 1950: 623:, and even then a translation and rotation may have to be applied to match the fractal up to itself. 3102:=1, and so this expansion is not strictly reliable. However, a semi-quantitative prediction is that 2431:
are massless and non-interacting) and is therefore scale-invariant, much like the classical theory.
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depend on the energy-scale of a given physical process. This energy dependence is described by the
1056:, is approximately constant, i.e. a flat spectrum. This pattern is consistent with the proposal of 807: 773: 149: 135: 94: 4432:
Jørgensen, B.; Martinez, J. R.; Tsao, M. (1994). "Asymptotic behaviour of the variance function".
3691:{\displaystyle {\frac {\partial \rho }{\partial t}}+\nabla \cdot \left(\rho \mathbf {u} \right)=0} 4215: 3110: 2490: 2439: 2408: 1045: 4546: 2605:
An example that links together many of the ideas in this article is the phase transition of the
301: 2521: 1384: 1080: 1068: 826:, as well as more unusual distributions like the compound Poisson-gamma distribution, positive 649: 560: 170: 160:, which are scale-invariant statistics of a variable, while the unstandardized moments are not. 105: 82: 1636:{\displaystyle {\begin{aligned}x\rightarrow \lambda x,\\t\rightarrow \lambda t.\end{aligned}}} 934:
are positive constants. This variance to mean power law is known in the physics literature as
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Some fractals may have multiple scaling factors at play at once; such scaling is studied with
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The idea of scale invariance of a monomial generalizes in higher dimensions to the idea of a
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is a scale-invariant classical field theory. The fields are the velocity of the fluid flow,
1013:, the Tweedie convergence theorem requires certain non-Gaussian random variables to express 998:, and the Tweedie distributions become foci of convergence for a wide range of data types. 4500: 4398: 4339: 4296: 3792: 3330:
The key observation is that, for all of these different systems, the behaviour resembles a
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must be dimensionless, otherwise one introduces a fixed length scale into the theory: For
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provides a hypothetical explanation for the wide manifestation of fluctuation scaling and
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Statistical Field Theory. An Introduction to Exactly Solved Models of Statistical Physics
4277: 2562: 2027:, Δ, has not been so important. However, one usually requires that the scalar field 1709: 1006: 827: 815: 780: 576: 157: 4504: 4402: 4343: 4300: 2589:
spatial dimensions, the corresponding statistical field theory is formally similar to a
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Features that do not change if length or energy scales are multiplied by a common factor
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The anomalous dimensions in certain two-dimensional CFTs can be related to the typical
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However, in nature the electromagnetic field is coupled to charged particles, such as
4637: 4520: 4414: 4355: 4316: 4255: 4187: 3729: 3182: 2594: 2593:-dimensional CFT. The scaling dimensions in such problems are usually referred to as 2554: 2533: 2529: 2400: 2101: 2032: 2024: 1333: 1182: 679: 443: 4558: 4508: 4460: 4406: 4347: 4304: 4195: 3331: 2869:{\displaystyle \langle \phi (0)\phi (r)\rangle \propto {\frac {1}{r^{D-2+\eta }}}.} 2578: 2383: = 4. Note that under these transformations the argument of the function 2028: 1713: 1057: 568: 127: 116: 4570: 4533: 4199: 4183: 3477: 3352: 2618: 2447: 1005:
requires certain kinds of random variables to have as a focus of convergence the
954: 939: 831: 765: 90: 4512: 4410: 4351: 4191: 3304:. Power-law scaling connects the rate of flow to the distribution of fractures. 3301: 3264: 2622: 1088: 761: 98: 81:
In mathematics, scale invariance usually refers to an invariance of individual
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with no charges or currents. The fields are the electric and magnetic fields,
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Random sequences, governed by the Tweedie distributions and evaluated by the
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Another example of a scale-invariant classical field theory is the massless
206:, which can be taken to be a length or size rescaling. The requirement for 4418: 4359: 2597:, and one can in principle compute these exponents in the appropriate CFT. 656: 619:. A fractal is equal to itself typically for only a discrete set of values 616: 615:
are scale-invariant, although more precisely, one should say that they are
604: 2438:. The QFT describing the interactions of photons and charged particles is 525:
Allowing for rotations of the curve, it is invariant under all rescalings
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In order to deduce the scale invariance of these equations we specify an
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In the physically interesting case of three spatial dimensions, we have
2442:(QED), and this theory is not scale-invariant. We can see this from the 4478: 4447: 3733: 3300:
through fractured rock beds, or water through filter paper, such as in
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as a particular critical exponent of the Ising model phase transition.
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and so it should not be surprising that massive scalar field theory is
962: 757: 627: 600: 153: 51: 3253:. Other examples of systems which belong to a universality class are: 2617:-dimensional periodic lattice. Associated with each lattice site is a 4380:"Tweedie convergence: A mathematical basis for Taylor's power law, 1/ 4225: 3736: 3334:, and that the language of statistical mechanics and scale-invariant 3308: 3297: 3257: 986: 3346: 3312: 3268: 2435: 990: 989:
of a Tweedie model. Almost all distribution functions with finite
838: 296: 4495: 4291: 3974:{\displaystyle \mathbf {u} \rightarrow \lambda ^{-1}\mathbf {u} .} 3113:, a family of well-understood CFTs, and it is possible to compute 3087:{\displaystyle \eta ={\frac {\epsilon ^{2}}{54}}+O(\epsilon ^{3})} 1322:{\displaystyle \varphi (x)=\lambda ^{-\Delta }\varphi (\lambda x)} 953:
relationship between the variance to mean power law and power law
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be scale-invariant, and in such cases the symmetry is said to be
1171:{\displaystyle \varphi \rightarrow \lambda ^{-\Delta }\varphi ~.} 612: 43: 2516:
Scale-invariant QFTs are almost always invariant under the full
2361:{\displaystyle \varphi (x)\rightarrow \lambda ^{-1}\varphi (x).} 3234: 3230: 2890:. This is because the classical dimension of the scalar field, 2428: 2020: 428:{\displaystyle f(\lambda x)=(\lambda x)^{n}=\lambda ^{n}f(x)~.} 1581:
These field equations are invariant under the transformation
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In mathematics, one can consider the scaling properties of a
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Now we can fit together a number of the ideas seen already.
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to be invariant under all rescalings is usually taken to be
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to display this kind of scale invariance or self-similarity.
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An example of a scale-invariant classical field theory is
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for some choice of exponent Δ, and for all dilations
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is physically equivalent to a fixed length scale through
130:. The key observation is that near a phase transition or 3185:
of random walks, where the random walks are defined via
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is the number of dimensions of the Ising model lattice.
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is generically described by a field, or set of fields,
1029:, the power spectrum of the spatial distribution of the 790: 2718:{\displaystyle G(r)\propto {\frac {1}{r^{D-2+\eta }}},} 2093:
is the combined number of spatial and time dimensions.
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From the above, one sees that the critical exponent,
2581:, its fluctuations are described by a scale-invariant 1243:{\displaystyle \lambda ^{\Delta }\varphi (\lambda x).} 4431: 4121: 4066: 4029: 3990: 3941: 3898: 3858: 3825: 3795: 3748: 3707: 3634: 3488: 3437: 3400: 3361: 3341: 3126: 3038: 2946: 2899: 2800: 2734: 2667: 2314: 2281: 2248: 2117: 2048: 1966: 1922: 1887: 1854: 1755: 1716:
is unrelated to scale invariance). The scalar field,
1590: 1406: 1275: 1211: 1139: 1103: 862: 695: 466: 356: 304: 226: 115:, scale invariance has an interpretation in terms of 3927:{\displaystyle \rho \rightarrow \lambda ^{-1}\rho ,} 742:{\displaystyle P(f)=\lambda ^{-\Delta }P(\lambda f)} 567:. Homogeneous functions are the natural denizens of 4610:DiFrancesco, P.; Mathieu, P.; Senechal, D. (1997). 4274: 442:, a kind of curve that often appears in nature. In 270:{\displaystyle f(\lambda x)=\lambda ^{\Delta }f(x)} 4547:"Feature detection with automatic scale selection" 4160: 4107: 4052: 4015: 3973: 3926: 3883: 3843: 3808: 3778: 3713: 3690: 3618: 3460: 3423: 3386: 3164: 3086: 2982: 2926: 2868: 2740: 2717: 2360: 2299: 2266: 2209: 2078: 2019:The field equations in the examples above are all 1993: 1941: 1916:The name massless refers to the absence of a term 1905: 1872: 1834: 1646:Moreover, given solutions of Maxwell's equations, 1635: 1563: 1321: 1242: 1170: 1124: 914: 779:Examples of scale-invariant distributions are the 741: 514: 427: 332: 269: 2461: 2419:of the corresponding renormalization group flow. 4629: 4465:"Critical Phenomena: field theoretical approach" 3347:Newtonian fluid mechanics with no applied forces 2547: 515:{\displaystyle \theta ={\frac {1}{b}}\ln(r/a)~.} 4544: 4476: 4377: 4329: 2983:{\displaystyle \Delta ={\frac {D-2+\eta }{2}},} 2561:, as long as the theory can be studied through 1703: 2748:, which is an example of a critical exponent. 1202:), one always has other solutions of the form 295:Examples of scale-invariant functions are the 191:. That is, one is interested in the shape of 152:are scale-invariant. The analogous concept in 3165:{\displaystyle \eta _{_{D=2}}={\frac {1}{4}}} 1733:is a function of a set of spatial variables, 1350: 571:, and homogeneous polynomials are studied as 438:An example of a scale-invariant curve is the 4577: 4538: 4425: 4373: 4371: 4369: 4243: 4016:{\displaystyle \mathbf {u} (\mathbf {x} ,t)} 3387:{\displaystyle \mathbf {u} (\mathbf {x} ,t)} 3296:of fluids through disordered media, such as 3176: 3117:(and the other critical exponents) exactly, 2828: 2801: 2477:However, even though the classical massless 4602:Quantum Field Theory and Critical Phenomena 4599: 3884:{\displaystyle t\rightarrow \lambda ^{2}t,} 3205:CFTs to SLE is an active area of research. 3193:critical Ising model and the more general 2 3025:can be calculated approximately, using the 1266:), to be scale-invariant, we require that 634:, but the scaling holds only for values of 4323: 3106:is numerically small in three dimensions. 2489:scale-invariant. We can see this from the 2422: 1845:and is invariant under the transformation 1064:Scale invariance in classical field theory 583:, it has connections to various topics in 165:Scale-invariant curves and self-similarity 4494: 4366: 4290: 4268: 4249: 2511: 2485: = 4, the quantized version is 2079:{\displaystyle \Delta ={\frac {D-2}{2}},} 892: 868: 73:). Dilatations can form part of a larger 4618: 4551:International Journal of Computer Vision 4527: 2927:{\displaystyle \Delta ={\frac {D-2}{2}}} 2886:, for this phase transition, is also an 2642:is said to occur. This means that below 2391:Scale invariance in quantum field theory 2023:in the fields, which has meant that the 1254:Scale invariance of field configurations 1125:{\displaystyle x\rightarrow \lambda x~,} 663:Scale invariance in stochastic processes 594: 29: 3844:{\displaystyle x\rightarrow \lambda x,} 2300:{\displaystyle t\rightarrow \lambda t,} 2267:{\displaystyle x\rightarrow \lambda x,} 1994:{\displaystyle L={\frac {\hbar }{mc}},} 1906:{\displaystyle t\rightarrow \lambda t.} 1873:{\displaystyle x\rightarrow \lambda x,} 1258:For a particular field configuration, 915:{\displaystyle {\text{var}}\,(Y)=a^{p}} 14: 4630: 2399:(QFT) is characterised by the way its 2108: = 4. The field equation is 554: 4378:Kendal, W. S.; Jørgensen, B. (2011). 4053:{\displaystyle \rho (\mathbf {x} ,t)} 3468:. These fields must satisfy both the 3424:{\displaystyle \rho (\mathbf {x} ,t)} 3271:, as a function of size and duration. 3004:in the conformal field theory is the 2228:, which contains the fourth power of 2031:is dimensionless, and this fixes the 1942:{\displaystyle \propto m^{2}\varphi } 791:Scale-invariant Tweedie distributions 540:is identical to a rotated version of 2568: 2371:The key point is that the parameter 2500:Even though the quantized massless 1383:), while their field equations are 1087:, and these equations are known as 938:, and in the ecology literature as 126:, scale invariance is a feature of 24: 4593: 4171: 3658: 3646: 3638: 3595: 3587: 3560: 3542: 3528: 3505: 3495: 3342:Other examples of scale invariance 3289:, which resemble cracks and tears. 3226:phase transition, described above. 2947: 2900: 2751: 2658:. This has the generic behaviour: 2600: 2173: 2153: 2139: 2049: 1811: 1791: 1777: 1541: 1525: 1487: 1466: 1450: 1412: 1299: 1217: 1154: 719: 250: 25: 4669: 4204:scale-invariant feature transform 4202:, and object recognition via the 3779:{\displaystyle P=c_{s}^{2}\rho ,} 3461:{\displaystyle P(\mathbf {x} ,t)} 3338:may be applied to describe them. 2379:theory, this is only the case in 2096:Given this scaling dimension for 187:under rescalings of the variable 4135: 4082: 4071: 4037: 4000: 3992: 3964: 3943: 3673: 3602: 3570: 3532: 3521: 3499: 3480:these take the respective forms 3445: 3408: 3371: 3363: 2756:The fluctuations at temperature 2520:, and the study of such QFTs is 1535: 1497: 1460: 1422: 1181:The parameter Δ is known as the 4252:The Theory of Dispersion Models 3237:transition in classical fluids. 3208: 2769:, a particular scale-invariant 1017:noise and fluctuation scaling. 457:, the spiral can be written as 89:. A closely related concept is 4477:Salvio, Strumia (2014-03-17). 4470: 4454: 4254:. London: Chapman & Hall. 4155: 4128: 4102: 4075: 4047: 4033: 4010: 3996: 3947: 3902: 3862: 3829: 3455: 3441: 3418: 3404: 3381: 3367: 3081: 3068: 2825: 2819: 2813: 2807: 2677: 2671: 2352: 2346: 2327: 2324: 2318: 2285: 2252: 1891: 1858: 1617: 1598: 1316: 1307: 1285: 1279: 1234: 1225: 1143: 1107: 1075:, that depend on coordinates, 903: 899: 893: 884: 875: 869: 736: 727: 705: 699: 503: 489: 416: 410: 385: 375: 369: 360: 314: 308: 264: 258: 239: 230: 13: 1: 4463:(2010) Scholarpedia article 4236: 4060:, we automatically have that 3351:Under certain circumstances, 3321:diffusion-limited aggregation 2728:for some particular value of 2548:Scale and conformal anomalies 2528:in a CFT have a well-defined 2481:theory is scale-invariant in 2468:quantized scalar field theory 2224:derives from the form of the 1390:With no charges or currents, 991:cumulant generating functions 803:exponential dispersion models 2542:anomalous scaling dimensions 2493:for the coupling parameter, 2462:Massless scalar field theory 2011: 1704:Massless scalar field theory 1020: 760:, and Δ = −2 for 61:The technical term for this 7: 4384:noise, and multifractality" 4209: 1951:relativistic field theories 1031:cosmic microwave background 974:Tweedie convergence theorem 590: 10: 4674: 4623:. Oxford University Press. 4604:. Oxford University Press. 4600:Zinn-Justin, Jean (2002). 4411:10.1103/PhysRevE.84.066120 4352:10.1103/PhysRevE.83.066115 4175: 3431:, and the fluid pressure, 2577:, as a system undergoes a 2395:The scale-dependence of a 1351:Classical electromagnetism 752:with Δ = 0 for 657:external and internal rays 611:It is sometimes said that 563:, and more generally to a 333:{\displaystyle f(x)=x^{n}} 136:statistical field theories 4309:10.1080/00018730801893043 3187:Schramm–Loewner evolution 3177:Schramm–Loewner evolution 2767:Wilson–Fisher fixed point 2640:spontaneous magnetization 2506:Wilson–Fisher fixed point 2446:. This tells us that the 756:, Δ = −1 for 95:probability distributions 4545:Lindeberg, Tony (1998). 4221:Inverse square potential 3336:statistical field theory 3319:, and the phenomenon of 3011:Note that for dimension 2583:statistical field theory 2454:scale-invariant, QED is 2407:, and is encoded in the 947:method of expanding bins 808:generalized linear model 774:probability distribution 284:. This is equivalent to 150:dimensionless quantities 4658:Scale-invariant systems 4563:10.1023/A:1008045108935 4513:10.1007/JHEP06(2014)080 4216:Invariant (mathematics) 2440:quantum electrodynamics 2423:Quantum electrodynamics 1739:, and a time variable, 1700:) are also solutions. 1578:is the speed of light. 1332:where Δ is, again, the 1046:primordial fluctuations 959:Wiener–Khinchin theorem 686:, then noise scales as 659:are invariant curves . 626:Thus, for example, the 4648:Conformal field theory 4612:Conformal Field Theory 4250:Jørgensen, B. (1997). 4162: 4109: 4054: 4017: 3975: 3928: 3885: 3845: 3810: 3780: 3715: 3692: 3620: 3470:Navier–Stokes equation 3462: 3425: 3388: 3213:A phenomenon known as 3166: 3088: 2984: 2937:is modified to become 2928: 2870: 2742: 2719: 2522:conformal field theory 2512:Conformal field theory 2362: 2301: 2268: 2211: 2080: 1995: 1943: 1907: 1874: 1836: 1637: 1565: 1323: 1244: 1172: 1126: 1081:differential equations 1069:Classical field theory 985:that comes within the 916: 800:are a special case of 743: 650:multi-fractal analysis 608: 561:homogeneous polynomial 516: 429: 334: 271: 202:for some scale factor 106:classical field theory 39: 4619:Mussardo, G. (2010). 4163: 4110: 4055: 4018: 3976: 3929: 3886: 3846: 3811: 3809:{\displaystyle c_{s}} 3781: 3716: 3693: 3621: 3463: 3426: 3394:, the fluid density, 3389: 3167: 3089: 3029:, and one finds that 2985: 2929: 2871: 2743: 2741:{\displaystyle \eta } 2720: 2575:statistical mechanics 2405:renormalization group 2363: 2302: 2269: 2212: 2081: 1996: 1944: 1908: 1875: 1837: 1638: 1566: 1392:these field equations 1324: 1245: 1173: 1127: 1007:Gaussian distribution 1003:central limit theorem 917: 810:and characterized by 797:Tweedie distributions 764:(and more generally, 744: 598: 517: 430: 335: 272: 124:statistical mechanics 33: 4583:T. Lindeberg (2014) 4168:are also solutions. 4119: 4064: 4027: 3988: 3984:Given the solutions 3939: 3896: 3856: 3823: 3793: 3746: 3714:{\displaystyle \mu } 3705: 3632: 3486: 3435: 3398: 3359: 3283:electrical breakdown 3124: 3036: 2944: 2897: 2798: 2789:correlation function 2732: 2665: 2609:, a simple model of 2472:Gaussian fixed point 2397:quantum field theory 2312: 2279: 2246: 2220:(Note that the name 2115: 2046: 1964: 1920: 1885: 1852: 1753: 1712:(note that the name 1588: 1404: 1345:spontaneously broken 1273: 1209: 1137: 1101: 987:domain of attraction 860: 828:stable distributions 820:Poisson distribution 785:Zipfian distribution 693: 573:projective varieties 565:homogeneous function 464: 354: 302: 290:homogeneous function 224: 158:standardized moments 113:quantum field theory 4505:2014JHEP...06..080S 4403:2011PhRvE..84f6120K 4344:2011PhRvE..83f6115K 4301:2008AdPhy..57...89E 3769: 3474:continuity equation 3002:anomalous dimension 2888:anomalous dimension 2787:is understood as a 2771:scalar field theory 2563:perturbation theory 2532:, analogous to the 2401:coupling parameters 1670:), it holds that 1385:Maxwell's equations 996:asymptotic behavior 936:fluctuation scaling 816:normal distribution 781:Pareto distribution 682:power at frequency 577:projective geometry 555:Projective geometry 4653:Critical phenomena 4643:Scaling symmetries 4614:. Springer-Verlag. 4231:Scale-free network 4158: 4105: 4050: 4013: 3971: 3924: 3881: 3841: 3806: 3776: 3755: 3739:, which satisfies 3711: 3688: 3616: 3458: 3421: 3384: 3251:universality class 3201:. Relating other 2 3183:fractal dimensions 3162: 3084: 2980: 2924: 2866: 2791:of scalar fields, 2738: 2715: 2595:critical exponents 2518:conformal symmetry 2358: 2297: 2264: 2207: 2076: 1991: 1939: 1903: 1870: 1832: 1633: 1631: 1561: 1559: 1319: 1240: 1168: 1122: 1027:physical cosmology 912: 824:gamma distribution 739: 609: 512: 440:logarithmic spiral 425: 347:, in that clearly 330: 292:of degree Δ. 267: 75:conformal symmetry 40: 38:is scale-invariant 4188:biological vision 3730:equation of state 3723:dynamic viscosity 3653: 3585: 3512: 3263:The frequency of 3160: 3060: 3027:epsilon expansion 2975: 2922: 2861: 2776:In this context, 2710: 2569:Phase transitions 2534:scaling dimension 2530:scaling dimension 2458:scale-invariant. 2444:QED beta-function 2167: 2133: 2071: 2039:. In particular, 2033:scaling dimension 2025:scaling dimension 2008:scale-invariant. 1986: 1805: 1771: 1555: 1519: 1480: 1444: 1394:take the form of 1334:scaling dimension 1190:scale-invariant. 1183:scaling dimension 1164: 1118: 1048:as a function of 983:variance function 890: 866: 680:average, expected 508: 481: 444:polar coordinates 421: 128:phase transitions 16:(Redirected from 4665: 4624: 4615: 4605: 4587: 4581: 4575: 4574: 4542: 4536: 4531: 4525: 4524: 4498: 4474: 4468: 4458: 4452: 4451: 4429: 4423: 4422: 4388: 4375: 4364: 4363: 4327: 4321: 4320: 4294: 4272: 4266: 4265: 4247: 4196:corner detection 4167: 4165: 4164: 4159: 4151: 4150: 4138: 4114: 4112: 4111: 4106: 4098: 4097: 4085: 4074: 4059: 4057: 4056: 4051: 4040: 4022: 4020: 4019: 4014: 4003: 3995: 3980: 3978: 3977: 3972: 3967: 3962: 3961: 3946: 3933: 3931: 3930: 3925: 3917: 3916: 3890: 3888: 3887: 3882: 3874: 3873: 3850: 3848: 3847: 3842: 3815: 3813: 3812: 3807: 3805: 3804: 3785: 3783: 3782: 3777: 3768: 3763: 3720: 3718: 3717: 3712: 3697: 3695: 3694: 3689: 3681: 3677: 3676: 3654: 3652: 3644: 3636: 3625: 3623: 3622: 3617: 3615: 3611: 3610: 3606: 3605: 3586: 3578: 3573: 3568: 3567: 3535: 3524: 3513: 3511: 3503: 3502: 3493: 3467: 3465: 3464: 3459: 3448: 3430: 3428: 3427: 3422: 3411: 3393: 3391: 3390: 3385: 3374: 3366: 3332:phase transition 3171: 3169: 3168: 3163: 3161: 3153: 3148: 3147: 3146: 3145: 3116: 3105: 3101: 3093: 3091: 3090: 3085: 3080: 3079: 3061: 3056: 3055: 3046: 3024: 3020: 2996: 2989: 2987: 2986: 2981: 2976: 2971: 2954: 2933: 2931: 2930: 2925: 2923: 2918: 2907: 2885: 2875: 2873: 2872: 2867: 2862: 2860: 2859: 2835: 2786: 2764: 2747: 2745: 2744: 2739: 2724: 2722: 2721: 2716: 2711: 2709: 2708: 2684: 2657: 2650: 2637: 2616: 2592: 2588: 2579:phase transition 2559:cosmic inflation 2386: 2382: 2378: 2374: 2367: 2365: 2364: 2359: 2342: 2341: 2306: 2304: 2303: 2298: 2273: 2271: 2270: 2265: 2238: 2231: 2223: 2216: 2214: 2213: 2208: 2200: 2199: 2181: 2180: 2168: 2166: 2165: 2164: 2151: 2147: 2146: 2136: 2134: 2132: 2131: 2119: 2107: 2099: 2092: 2085: 2083: 2082: 2077: 2072: 2067: 2056: 2038: 2000: 1998: 1997: 1992: 1987: 1985: 1974: 1956: 1953:, a mass-scale, 1948: 1946: 1945: 1940: 1935: 1934: 1912: 1910: 1909: 1904: 1879: 1877: 1876: 1871: 1841: 1839: 1838: 1833: 1819: 1818: 1806: 1804: 1803: 1802: 1789: 1785: 1784: 1774: 1772: 1770: 1769: 1757: 1742: 1732: 1642: 1640: 1639: 1634: 1632: 1570: 1568: 1567: 1562: 1560: 1556: 1554: 1553: 1552: 1539: 1538: 1533: 1532: 1522: 1520: 1518: 1517: 1505: 1500: 1495: 1494: 1481: 1479: 1478: 1477: 1464: 1463: 1458: 1457: 1447: 1445: 1443: 1442: 1430: 1425: 1420: 1419: 1357:electromagnetism 1328: 1326: 1325: 1320: 1303: 1302: 1249: 1247: 1246: 1241: 1221: 1220: 1177: 1175: 1174: 1169: 1162: 1158: 1157: 1131: 1129: 1128: 1123: 1116: 1058:cosmic inflation 1055: 1043: 955:autocorrelations 921: 919: 918: 913: 911: 910: 891: 888: 867: 864: 832:random variables 748: 746: 745: 740: 723: 722: 685: 677: 644: 640: 633: 622: 569:projective space 550: 539: 528: 521: 519: 518: 513: 506: 499: 482: 474: 456: 434: 432: 431: 426: 419: 406: 405: 393: 392: 346: 339: 337: 336: 331: 329: 328: 288:  being a 287: 283: 276: 274: 273: 268: 254: 253: 216: 205: 201: 190: 186: 117:particle physics 99:random processes 56:scale invariance 21: 4673: 4672: 4668: 4667: 4666: 4664: 4663: 4662: 4628: 4627: 4596: 4594:Further reading 4591: 4590: 4582: 4578: 4543: 4539: 4532: 4528: 4475: 4471: 4459: 4455: 4435:Scand J Statist 4430: 4426: 4386: 4376: 4367: 4328: 4324: 4273: 4269: 4262: 4248: 4244: 4239: 4212: 4200:ridge detection 4184:computer vision 4180: 4174: 4172:Computer vision 4146: 4142: 4134: 4120: 4117: 4116: 4093: 4089: 4081: 4070: 4065: 4062: 4061: 4036: 4028: 4025: 4024: 3999: 3991: 3989: 3986: 3985: 3963: 3954: 3950: 3942: 3940: 3937: 3936: 3909: 3905: 3897: 3894: 3893: 3869: 3865: 3857: 3854: 3853: 3824: 3821: 3820: 3800: 3796: 3794: 3791: 3790: 3764: 3759: 3747: 3744: 3743: 3706: 3703: 3702: 3672: 3668: 3664: 3645: 3637: 3635: 3633: 3630: 3629: 3601: 3594: 3590: 3577: 3569: 3563: 3559: 3558: 3554: 3531: 3520: 3504: 3498: 3494: 3492: 3487: 3484: 3483: 3478:Newtonian fluid 3444: 3436: 3433: 3432: 3407: 3399: 3396: 3395: 3370: 3362: 3360: 3357: 3356: 3353:fluid mechanics 3349: 3344: 3265:network outages 3211: 3179: 3152: 3135: 3132: 3131: 3127: 3125: 3122: 3121: 3114: 3103: 3099: 3075: 3071: 3051: 3047: 3045: 3037: 3034: 3033: 3022: 3012: 2994: 2955: 2953: 2945: 2942: 2941: 2908: 2906: 2898: 2895: 2894: 2883: 2843: 2839: 2834: 2799: 2796: 2795: 2777: 2762: 2757: 2754: 2752:CFT description 2733: 2730: 2729: 2692: 2688: 2683: 2666: 2663: 2662: 2655: 2648: 2643: 2635: 2630: 2619:magnetic moment 2614: 2603: 2601:The Ising model 2590: 2586: 2571: 2550: 2514: 2466:Free, massless 2464: 2448:electric charge 2425: 2411:of the theory. 2393: 2384: 2380: 2376: 2372: 2334: 2330: 2313: 2310: 2309: 2280: 2277: 2276: 2247: 2244: 2243: 2236: 2229: 2221: 2195: 2191: 2176: 2172: 2160: 2156: 2152: 2142: 2138: 2137: 2135: 2127: 2123: 2118: 2116: 2113: 2112: 2105: 2097: 2090: 2057: 2055: 2047: 2044: 2043: 2036: 2017: 1978: 1973: 1965: 1962: 1961: 1954: 1930: 1926: 1921: 1918: 1917: 1886: 1883: 1882: 1853: 1850: 1849: 1814: 1810: 1798: 1794: 1790: 1780: 1776: 1775: 1773: 1765: 1761: 1756: 1754: 1751: 1750: 1740: 1717: 1706: 1630: 1629: 1611: 1610: 1591: 1589: 1586: 1585: 1558: 1557: 1548: 1544: 1540: 1534: 1528: 1524: 1523: 1521: 1513: 1509: 1504: 1496: 1490: 1486: 1483: 1482: 1473: 1469: 1465: 1459: 1453: 1449: 1448: 1446: 1438: 1434: 1429: 1421: 1415: 1411: 1407: 1405: 1402: 1401: 1353: 1295: 1291: 1274: 1271: 1270: 1256: 1216: 1212: 1210: 1207: 1206: 1150: 1146: 1138: 1135: 1134: 1102: 1099: 1098: 1089:field equations 1066: 1053: 1034: 1023: 906: 902: 887: 863: 861: 858: 857: 793: 766:Brownian motion 715: 711: 694: 691: 690: 683: 668: 665: 642: 635: 631: 620: 593: 557: 541: 530: 526: 495: 473: 465: 462: 461: 446: 401: 397: 388: 384: 355: 352: 351: 341: 324: 320: 303: 300: 299: 285: 281: 249: 245: 225: 222: 221: 207: 203: 192: 188: 177: 167: 91:self-similarity 69:(also known as 28: 23: 22: 18:Scale invariant 15: 12: 11: 5: 4671: 4661: 4660: 4655: 4650: 4645: 4640: 4626: 4625: 4616: 4607: 4595: 4592: 4589: 4588: 4576: 4537: 4526: 4469: 4461:J. Zinn-Justin 4453: 4442:(3): 223–243. 4424: 4365: 4322: 4267: 4261:978-0412997112 4260: 4241: 4240: 4238: 4235: 4234: 4233: 4228: 4223: 4218: 4211: 4208: 4192:blob detection 4176:Main article: 4173: 4170: 4157: 4154: 4149: 4145: 4141: 4137: 4133: 4130: 4127: 4124: 4104: 4101: 4096: 4092: 4088: 4084: 4080: 4077: 4073: 4069: 4049: 4046: 4043: 4039: 4035: 4032: 4012: 4009: 4006: 4002: 3998: 3994: 3982: 3981: 3970: 3966: 3960: 3957: 3953: 3949: 3945: 3934: 3923: 3920: 3915: 3912: 3908: 3904: 3901: 3891: 3880: 3877: 3872: 3868: 3864: 3861: 3851: 3840: 3837: 3834: 3831: 3828: 3803: 3799: 3787: 3786: 3775: 3772: 3767: 3762: 3758: 3754: 3751: 3710: 3699: 3698: 3687: 3684: 3680: 3675: 3671: 3667: 3663: 3660: 3657: 3651: 3648: 3643: 3640: 3614: 3609: 3604: 3600: 3597: 3593: 3589: 3584: 3581: 3576: 3572: 3566: 3562: 3557: 3553: 3550: 3547: 3544: 3541: 3538: 3534: 3530: 3527: 3523: 3519: 3516: 3510: 3507: 3501: 3497: 3491: 3457: 3454: 3451: 3447: 3443: 3440: 3420: 3417: 3414: 3410: 3406: 3403: 3383: 3380: 3377: 3373: 3369: 3365: 3348: 3345: 3343: 3340: 3328: 3327: 3324: 3305: 3302:chromatography 3290: 3279: 3275: 3272: 3261: 3244:critical point 3239: 3238: 3227: 3210: 3207: 3178: 3175: 3174: 3173: 3159: 3156: 3151: 3144: 3141: 3138: 3134: 3130: 3111:minimal models 3096: 3095: 3083: 3078: 3074: 3070: 3067: 3064: 3059: 3054: 3050: 3044: 3041: 2991: 2990: 2979: 2974: 2970: 2967: 2964: 2961: 2958: 2952: 2949: 2935: 2934: 2921: 2917: 2914: 2911: 2905: 2902: 2877: 2876: 2865: 2858: 2855: 2852: 2849: 2846: 2842: 2838: 2833: 2830: 2827: 2824: 2821: 2818: 2815: 2812: 2809: 2806: 2803: 2760: 2753: 2750: 2737: 2726: 2725: 2714: 2707: 2704: 2701: 2698: 2695: 2691: 2687: 2682: 2679: 2676: 2673: 2670: 2646: 2633: 2602: 2599: 2570: 2567: 2549: 2546: 2513: 2510: 2463: 2460: 2424: 2421: 2409:beta-functions 2392: 2389: 2387:is unchanged. 2369: 2368: 2357: 2354: 2351: 2348: 2345: 2340: 2337: 2333: 2329: 2326: 2323: 2320: 2317: 2307: 2296: 2293: 2290: 2287: 2284: 2274: 2263: 2260: 2257: 2254: 2251: 2218: 2217: 2206: 2203: 2198: 2194: 2190: 2187: 2184: 2179: 2175: 2171: 2163: 2159: 2155: 2150: 2145: 2141: 2130: 2126: 2122: 2087: 2086: 2075: 2070: 2066: 2063: 2060: 2054: 2051: 2016: 2010: 2002: 2001: 1990: 1984: 1981: 1977: 1972: 1969: 1938: 1933: 1929: 1925: 1914: 1913: 1902: 1899: 1896: 1893: 1890: 1880: 1869: 1866: 1863: 1860: 1857: 1843: 1842: 1831: 1828: 1825: 1822: 1817: 1813: 1809: 1801: 1797: 1793: 1788: 1783: 1779: 1768: 1764: 1760: 1705: 1702: 1644: 1643: 1628: 1625: 1622: 1619: 1616: 1613: 1612: 1609: 1606: 1603: 1600: 1597: 1594: 1593: 1572: 1571: 1551: 1547: 1543: 1537: 1531: 1527: 1516: 1512: 1508: 1503: 1499: 1493: 1489: 1485: 1484: 1476: 1472: 1468: 1462: 1456: 1452: 1441: 1437: 1433: 1428: 1424: 1418: 1414: 1410: 1409: 1396:wave equations 1352: 1349: 1336:of the field. 1330: 1329: 1318: 1315: 1312: 1309: 1306: 1301: 1298: 1294: 1290: 1287: 1284: 1281: 1278: 1255: 1252: 1251: 1250: 1239: 1236: 1233: 1230: 1227: 1224: 1219: 1215: 1179: 1178: 1167: 1161: 1156: 1153: 1149: 1145: 1142: 1132: 1121: 1115: 1112: 1109: 1106: 1065: 1062: 1022: 1019: 924: 923: 909: 905: 901: 898: 895: 886: 883: 880: 877: 874: 871: 853:) power law: 837:demonstrate a 792: 789: 762:Brownian noise 750: 749: 738: 735: 732: 729: 726: 721: 718: 714: 710: 707: 704: 701: 698: 664: 661: 592: 589: 556: 553: 523: 522: 511: 505: 502: 498: 494: 491: 488: 485: 480: 477: 472: 469: 436: 435: 424: 418: 415: 412: 409: 404: 400: 396: 391: 387: 383: 380: 377: 374: 371: 368: 365: 362: 359: 327: 323: 319: 316: 313: 310: 307: 278: 277: 266: 263: 260: 257: 252: 248: 244: 241: 238: 235: 232: 229: 166: 163: 162: 161: 146: 139: 132:critical point 120: 109: 102: 63:transformation 36:Wiener process 26: 9: 6: 4: 3: 2: 4670: 4659: 4656: 4654: 4651: 4649: 4646: 4644: 4641: 4639: 4636: 4635: 4633: 4622: 4617: 4613: 4608: 4603: 4598: 4597: 4586: 4580: 4572: 4568: 4564: 4560: 4557:(2): 79–116. 4556: 4552: 4548: 4541: 4535: 4530: 4522: 4518: 4514: 4510: 4506: 4502: 4497: 4492: 4488: 4484: 4480: 4473: 4466: 4462: 4457: 4449: 4445: 4441: 4437: 4436: 4428: 4420: 4416: 4412: 4408: 4404: 4400: 4397:(6): 066120. 4396: 4392: 4385: 4383: 4374: 4372: 4370: 4361: 4357: 4353: 4349: 4345: 4341: 4338:(6): 066115. 4337: 4333: 4326: 4318: 4314: 4310: 4306: 4302: 4298: 4293: 4288: 4285:(1): 89–142. 4284: 4280: 4279: 4271: 4263: 4257: 4253: 4246: 4242: 4232: 4229: 4227: 4224: 4222: 4219: 4217: 4214: 4213: 4207: 4205: 4201: 4197: 4193: 4189: 4185: 4179: 4169: 4152: 4147: 4143: 4139: 4131: 4125: 4122: 4099: 4094: 4090: 4086: 4078: 4067: 4044: 4041: 4030: 4007: 4004: 3968: 3958: 3955: 3951: 3935: 3921: 3918: 3913: 3910: 3906: 3899: 3892: 3878: 3875: 3870: 3866: 3859: 3852: 3838: 3835: 3832: 3826: 3819: 3818: 3817: 3801: 3797: 3773: 3770: 3765: 3760: 3756: 3752: 3749: 3742: 3741: 3740: 3738: 3735: 3731: 3726: 3724: 3708: 3685: 3682: 3678: 3669: 3665: 3661: 3655: 3649: 3641: 3628: 3627: 3626: 3612: 3607: 3598: 3591: 3582: 3579: 3574: 3564: 3555: 3551: 3548: 3545: 3539: 3536: 3525: 3517: 3514: 3508: 3489: 3481: 3479: 3475: 3471: 3452: 3449: 3438: 3415: 3412: 3401: 3378: 3375: 3354: 3339: 3337: 3333: 3325: 3322: 3318: 3314: 3310: 3306: 3303: 3299: 3295: 3291: 3288: 3284: 3280: 3276: 3273: 3270: 3266: 3262: 3259: 3256: 3255: 3254: 3252: 3247: 3245: 3236: 3232: 3228: 3225: 3221: 3220: 3219: 3216: 3206: 3204: 3200: 3196: 3192: 3188: 3184: 3157: 3154: 3149: 3142: 3139: 3136: 3133: 3128: 3120: 3119: 3118: 3112: 3107: 3076: 3072: 3065: 3062: 3057: 3052: 3048: 3042: 3039: 3032: 3031: 3030: 3028: 3019: 3015: 3009: 3007: 3003: 2998: 2977: 2972: 2968: 2965: 2962: 2959: 2956: 2950: 2940: 2939: 2938: 2919: 2915: 2912: 2909: 2903: 2893: 2892: 2891: 2889: 2880: 2863: 2856: 2853: 2850: 2847: 2844: 2840: 2836: 2831: 2822: 2816: 2810: 2804: 2794: 2793: 2792: 2790: 2784: 2780: 2774: 2772: 2768: 2763: 2749: 2735: 2712: 2705: 2702: 2699: 2696: 2693: 2689: 2685: 2680: 2674: 2668: 2661: 2660: 2659: 2652: 2649: 2641: 2636: 2626: 2624: 2620: 2612: 2611:ferromagnetic 2608: 2598: 2596: 2584: 2580: 2576: 2566: 2564: 2560: 2556: 2545: 2543: 2539: 2535: 2531: 2527: 2523: 2519: 2509: 2507: 2503: 2498: 2496: 2492: 2491:beta-function 2488: 2484: 2480: 2475: 2473: 2469: 2459: 2457: 2453: 2449: 2445: 2441: 2437: 2432: 2430: 2420: 2418: 2412: 2410: 2406: 2402: 2398: 2388: 2355: 2349: 2343: 2338: 2335: 2331: 2321: 2315: 2308: 2294: 2291: 2288: 2282: 2275: 2261: 2258: 2255: 2249: 2242: 2241: 2240: 2233: 2227: 2204: 2201: 2196: 2192: 2188: 2185: 2182: 2177: 2169: 2161: 2157: 2148: 2143: 2128: 2124: 2120: 2111: 2110: 2109: 2103: 2094: 2073: 2068: 2064: 2061: 2058: 2052: 2042: 2041: 2040: 2034: 2030: 2026: 2022: 2014: 2009: 2007: 1988: 1982: 1979: 1975: 1970: 1967: 1960: 1959: 1958: 1952: 1936: 1931: 1927: 1923: 1900: 1897: 1894: 1888: 1881: 1867: 1864: 1861: 1855: 1848: 1847: 1846: 1829: 1826: 1823: 1820: 1815: 1807: 1799: 1795: 1786: 1781: 1766: 1762: 1758: 1749: 1748: 1747: 1744: 1738: 1737: 1730: 1726: 1725: 1720: 1715: 1711: 1701: 1699: 1695: 1692: 1688: 1684: 1680: 1677: 1673: 1669: 1665: 1661: 1657: 1653: 1649: 1626: 1623: 1620: 1614: 1607: 1604: 1601: 1595: 1584: 1583: 1582: 1579: 1577: 1549: 1545: 1529: 1514: 1510: 1506: 1501: 1491: 1474: 1470: 1454: 1439: 1435: 1431: 1426: 1416: 1400: 1399: 1398: 1397: 1393: 1388: 1386: 1382: 1378: 1374: 1370: 1366: 1362: 1358: 1348: 1346: 1342: 1337: 1335: 1313: 1310: 1304: 1296: 1292: 1288: 1282: 1276: 1269: 1268: 1267: 1265: 1261: 1237: 1231: 1228: 1222: 1213: 1205: 1204: 1203: 1201: 1197: 1191: 1189: 1184: 1165: 1159: 1151: 1147: 1140: 1133: 1119: 1113: 1110: 1104: 1097: 1096: 1095: 1092: 1090: 1086: 1082: 1078: 1074: 1070: 1061: 1059: 1051: 1047: 1041: 1037: 1032: 1028: 1018: 1016: 1012: 1008: 1004: 999: 997: 992: 988: 984: 980: 976: 975: 969: 967: 965: 960: 956: 952: 951:biconditional 948: 943: 941: 937: 933: 929: 907: 896: 881: 878: 872: 856: 855: 854: 852: 848: 844: 840: 836: 833: 829: 825: 821: 817: 813: 809: 805: 804: 799: 798: 788: 786: 782: 777: 775: 769: 767: 763: 759: 755: 733: 730: 724: 716: 712: 708: 702: 696: 689: 688: 687: 681: 675: 671: 660: 658: 653: 651: 646: 638: 629: 624: 618: 614: 606: 602: 597: 588: 586: 585:string theory 582: 578: 574: 570: 566: 562: 552: 548: 544: 537: 533: 509: 500: 496: 492: 486: 483: 478: 475: 470: 467: 460: 459: 458: 454: 450: 445: 441: 422: 413: 407: 402: 398: 394: 389: 381: 378: 372: 366: 363: 357: 350: 349: 348: 345: 325: 321: 317: 311: 305: 298: 293: 291: 261: 255: 246: 242: 236: 233: 227: 220: 219: 218: 214: 210: 199: 195: 184: 180: 176: 172: 159: 155: 151: 147: 143: 140: 137: 133: 129: 125: 121: 118: 114: 110: 107: 103: 100: 96: 92: 88: 84: 80: 79: 78: 76: 72: 68: 64: 59: 57: 53: 49: 45: 37: 32: 19: 4620: 4611: 4601: 4579: 4554: 4550: 4540: 4529: 4486: 4482: 4472: 4456: 4439: 4433: 4427: 4394: 4391:Phys. Rev. E 4390: 4381: 4335: 4332:Phys. Rev. E 4331: 4325: 4282: 4276: 4270: 4251: 4245: 4181: 3983: 3788: 3727: 3700: 3482: 3350: 3329: 3248: 3240: 3215:universality 3212: 3209:Universality 3202: 3194: 3190: 3180: 3108: 3097: 3026: 3017: 3013: 3010: 3005: 3001: 2999: 2992: 2936: 2887: 2881: 2878: 2782: 2778: 2775: 2766: 2758: 2755: 2727: 2653: 2644: 2631: 2627: 2604: 2572: 2551: 2537: 2515: 2505: 2501: 2499: 2494: 2486: 2482: 2478: 2476: 2465: 2455: 2451: 2433: 2426: 2417:fixed points 2413: 2394: 2370: 2234: 2219: 2095: 2088: 2018: 2012: 2005: 2003: 1915: 1844: 1745: 1735: 1734: 1728: 1723: 1722: 1718: 1710:scalar field 1707: 1697: 1693: 1690: 1686: 1682: 1678: 1675: 1671: 1667: 1663: 1659: 1655: 1651: 1647: 1645: 1580: 1575: 1573: 1389: 1380: 1376: 1372: 1368: 1364: 1360: 1354: 1340: 1338: 1331: 1263: 1259: 1257: 1199: 1195: 1192: 1187: 1180: 1093: 1084: 1076: 1072: 1067: 1039: 1035: 1024: 1014: 1009:and express 1001:Much as the 1000: 978: 973: 970: 963: 944: 940:Taylor's law 935: 931: 927: 925: 850: 842: 834: 801: 795: 794: 778: 770: 751: 673: 669: 666: 654: 647: 641:for integer 636: 630:scales with 625: 617:self-similar 610: 605:self-similar 558: 546: 542: 535: 531: 524: 452: 448: 437: 343: 340:, for which 294: 279: 212: 208: 197: 193: 182: 178: 168: 148:In general, 142:Universality 70: 66: 60: 55: 41: 4178:Scale space 3294:percolation 3287:dielectrics 3224:Ising model 3199:Potts model 2607:Ising model 1050:wave number 1011:white noise 754:white noise 529:; that is, 48:mathematics 4632:Categories 4489:(6): 080. 4479:"Agravity" 4237:References 3734:isothermal 3258:Avalanches 2226:Lagrangian 949:exhibit a 758:pink noise 628:Koch curve 601:Koch curve 154:statistics 67:dilatation 52:statistics 4521:256010671 4496:1403.4226 4317:119608542 4292:0708.2053 4226:Power law 4144:λ 4132:λ 4126:ρ 4123:λ 4091:λ 4079:λ 4068:λ 4031:ρ 3956:− 3952:λ 3948:→ 3919:ρ 3911:− 3907:λ 3903:→ 3900:ρ 3867:λ 3863:→ 3833:λ 3830:→ 3771:ρ 3737:ideal gas 3709:μ 3670:ρ 3662:⋅ 3659:∇ 3647:∂ 3642:ρ 3639:∂ 3599:⋅ 3596:∇ 3588:∇ 3561:∇ 3552:μ 3543:∇ 3540:− 3529:∇ 3526:⋅ 3518:ρ 3506:∂ 3496:∂ 3490:ρ 3402:ρ 3313:molecules 3309:diffusion 3298:petroleum 3197:critical 3129:η 3073:ϵ 3049:ϵ 3040:η 2969:η 2960:− 2948:Δ 2913:− 2901:Δ 2857:η 2848:− 2832:∝ 2829:⟩ 2817:ϕ 2805:ϕ 2802:⟨ 2736:η 2706:η 2697:− 2681:∝ 2555:anomalous 2526:Operators 2508:, below. 2436:electrons 2344:φ 2336:− 2332:λ 2328:→ 2316:φ 2289:λ 2286:→ 2256:λ 2253:→ 2193:φ 2183:φ 2174:∇ 2170:− 2154:∂ 2149:φ 2140:∂ 2062:− 2050:Δ 1976:ℏ 1937:φ 1924:∝ 1895:λ 1892:→ 1862:λ 1859:→ 1821:φ 1812:∇ 1808:− 1792:∂ 1787:φ 1778:∂ 1621:λ 1618:→ 1602:λ 1599:→ 1542:∂ 1526:∂ 1488:∇ 1467:∂ 1451:∂ 1413:∇ 1311:λ 1305:φ 1300:Δ 1297:− 1293:λ 1277:φ 1229:λ 1223:φ 1218:Δ 1214:λ 1160:φ 1155:Δ 1152:− 1148:λ 1144:→ 1141:φ 1111:λ 1108:→ 1021:Cosmology 731:λ 720:Δ 717:− 713:λ 655:Periodic 487:⁡ 468:θ 399:λ 379:λ 364:λ 297:monomials 251:Δ 247:λ 234:λ 83:functions 4638:Symmetry 4419:22304168 4360:21797449 4278:Adv Phys 4210:See also 3476:. For a 3472:and the 3317:solution 3269:Internet 3000:So this 2102:φ theory 839:variance 783:and the 613:fractals 591:Fractals 171:function 71:dilation 4501:Bibcode 4448:4616314 4399:Bibcode 4340:Bibcode 4297:Bibcode 3721:is the 3267:on the 2524:(CFT). 2429:photons 957:. The 812:closure 678:is the 581:schemes 145:theory. 44:physics 4571:723210 4569:  4519:  4446:  4417:  4358:  4315:  4258:  3789:where 3701:where 3278:scale. 3235:vapour 3231:liquid 2993:where 2089:where 2029:action 2021:linear 2015:theory 1714:scalar 1685:) and 1658:) and 1574:where 1371:) and 1163:  1117:  926:where 507:  420:  87:curves 4567:S2CID 4517:S2CID 4491:arXiv 4444:JSTOR 4387:(PDF) 4313:S2CID 4287:arXiv 2621:, or 2235:When 1044:, of 966:noise 845:) to 639:= 1/3 632:∆ = 1 175:curve 65:is a 4487:2014 4483:JHEP 4415:PMID 4356:PMID 4256:ISBN 4186:and 4115:and 4023:and 3307:The 3292:The 3281:The 3229:The 3222:The 3016:≡ 4− 3006:same 2623:spin 2104:for 1083:for 971:The 930:and 847:mean 841:var( 822:and 342:Δ = 156:are 50:and 34:The 4559:doi 4509:doi 4407:doi 4348:doi 4305:doi 4182:In 3315:in 3311:of 3285:of 2573:In 2487:not 2456:not 2232:.) 2035:of 2006:not 1341:not 1188:not 1025:In 1015:1/f 979:1/f 964:1/f 865:var 768:). 667:If 603:is 575:in 173:or 122:In 111:In 104:In 97:of 85:or 42:In 4634:: 4565:. 4555:30 4553:. 4549:. 4515:. 4507:. 4499:. 4485:. 4481:. 4440:21 4438:. 4413:. 4405:. 4395:84 4393:. 4389:. 4368:^ 4354:. 4346:. 4336:83 4334:. 4311:. 4303:. 4295:. 4283:57 4281:. 4206:. 4198:, 4194:, 3725:. 3058:54 3021:, 2773:. 2638:, 2565:. 2544:. 2536:, 2497:. 2474:. 2452:is 2205:0. 1743:. 1727:, 1698:λt 1696:, 1683:λt 1681:, 1666:, 1654:, 1387:. 1347:. 1091:. 1060:. 1052:, 968:. 942:. 849:E( 818:, 787:. 776:. 684:f 652:. 599:A 587:. 551:. 536:λr 484:ln 451:, 198:λx 77:. 54:, 46:, 4573:. 4561:: 4523:. 4511:: 4503:: 4493:: 4467:. 4450:. 4421:. 4409:: 4401:: 4382:f 4362:. 4350:: 4342:: 4319:. 4307:: 4299:: 4289:: 4264:. 4156:) 4153:t 4148:2 4140:, 4136:x 4129:( 4103:) 4100:t 4095:2 4087:, 4083:x 4076:( 4072:u 4048:) 4045:t 4042:, 4038:x 4034:( 4011:) 4008:t 4005:, 4001:x 3997:( 3993:u 3969:. 3965:u 3959:1 3944:u 3922:, 3914:1 3879:, 3876:t 3871:2 3860:t 3839:, 3836:x 3827:x 3802:s 3798:c 3774:, 3766:2 3761:s 3757:c 3753:= 3750:P 3686:0 3683:= 3679:) 3674:u 3666:( 3656:+ 3650:t 3613:) 3608:) 3603:u 3592:( 3583:3 3580:1 3575:+ 3571:u 3565:2 3556:( 3549:+ 3546:P 3537:= 3533:u 3522:u 3515:+ 3509:t 3500:u 3456:) 3453:t 3450:, 3446:x 3442:( 3439:P 3419:) 3416:t 3413:, 3409:x 3405:( 3382:) 3379:t 3376:, 3372:x 3368:( 3364:u 3323:. 3233:- 3203:d 3195:d 3191:d 3172:. 3158:4 3155:1 3150:= 3143:2 3140:= 3137:D 3115:η 3104:η 3100:ε 3094:. 3082:) 3077:3 3069:( 3066:O 3063:+ 3053:2 3043:= 3023:η 3018:ε 3014:D 2995:D 2978:, 2973:2 2966:+ 2963:2 2957:D 2951:= 2920:2 2916:2 2910:D 2904:= 2884:η 2864:. 2854:+ 2851:2 2845:D 2841:r 2837:1 2826:) 2823:r 2820:( 2814:) 2811:0 2808:( 2785:) 2783:r 2781:( 2779:G 2761:c 2759:T 2713:, 2703:+ 2700:2 2694:D 2690:r 2686:1 2678:) 2675:r 2672:( 2669:G 2656:r 2647:c 2645:T 2634:c 2632:T 2615:D 2591:D 2587:D 2538:∆ 2502:φ 2495:g 2483:D 2479:φ 2385:φ 2381:D 2377:φ 2373:g 2356:. 2353:) 2350:x 2347:( 2339:1 2325:) 2322:x 2319:( 2295:, 2292:t 2283:t 2262:, 2259:x 2250:x 2237:D 2230:φ 2222:φ 2202:= 2197:3 2189:g 2186:+ 2178:2 2162:2 2158:t 2144:2 2129:2 2125:c 2121:1 2106:D 2098:φ 2091:D 2074:, 2069:2 2065:2 2059:D 2053:= 2037:φ 2013:φ 1989:, 1983:c 1980:m 1971:= 1968:L 1955:m 1932:2 1928:m 1901:. 1898:t 1889:t 1868:, 1865:x 1856:x 1830:, 1827:0 1824:= 1816:2 1800:2 1796:t 1782:2 1767:2 1763:c 1759:1 1741:t 1736:x 1731:) 1729:t 1724:x 1721:( 1719:φ 1694:x 1691:λ 1689:( 1687:B 1679:x 1676:λ 1674:( 1672:E 1668:t 1664:x 1662:( 1660:B 1656:t 1652:x 1650:( 1648:E 1627:. 1624:t 1615:t 1608:, 1605:x 1596:x 1576:c 1550:2 1546:t 1536:B 1530:2 1515:2 1511:c 1507:1 1502:= 1498:B 1492:2 1475:2 1471:t 1461:E 1455:2 1440:2 1436:c 1432:1 1427:= 1423:E 1417:2 1381:t 1379:, 1377:x 1375:( 1373:B 1369:t 1367:, 1365:x 1363:( 1361:E 1317:) 1314:x 1308:( 1289:= 1286:) 1283:x 1280:( 1264:x 1262:( 1260:φ 1238:. 1235:) 1232:x 1226:( 1200:x 1198:( 1196:φ 1166:. 1120:, 1114:x 1105:x 1085:φ 1077:x 1073:φ 1054:k 1042:) 1040:k 1038:( 1036:P 932:p 928:a 922:, 908:p 904:] 900:) 897:Y 894:( 889:E 885:[ 882:a 879:= 876:) 873:Y 870:( 851:Y 843:Y 835:Y 737:) 734:f 728:( 725:P 709:= 706:) 703:f 700:( 697:P 676:) 674:f 672:( 670:P 643:n 637:λ 621:λ 607:. 549:) 547:r 545:( 543:θ 538:) 534:( 532:θ 527:λ 510:. 504:) 501:a 497:/ 493:r 490:( 479:b 476:1 471:= 455:) 453:θ 449:r 447:( 423:. 417:) 414:x 411:( 408:f 403:n 395:= 390:n 386:) 382:x 376:( 373:= 370:) 367:x 361:( 358:f 344:n 326:n 322:x 318:= 315:) 312:x 309:( 306:f 286:f 282:λ 265:) 262:x 259:( 256:f 243:= 240:) 237:x 231:( 228:f 215:) 213:x 211:( 209:f 204:λ 200:) 196:( 194:f 189:x 185:) 183:x 181:( 179:f 20:)

Index

Scale invariant

Wiener process
physics
mathematics
statistics
transformation
conformal symmetry
functions
curves
self-similarity
probability distributions
random processes
classical field theory
quantum field theory
particle physics
statistical mechanics
phase transitions
critical point
statistical field theories
Universality
dimensionless quantities
statistics
standardized moments
function
curve
homogeneous function
monomials
logarithmic spiral
polar coordinates

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