What is Transformation: Definition and 1000 Discussions

In linear algebra, linear transformations can be represented by matrices. If



T


{\displaystyle T}
is a linear transformation mapping





R


n




{\displaystyle \mathbb {R} ^{n}}
to





R


m




{\displaystyle \mathbb {R} ^{m}}
and




x



{\displaystyle \mathbf {x} }
is a column vector with



n


{\displaystyle n}
entries, then




T
(

x

)
=
A

x



{\displaystyle T(\mathbf {x} )=A\mathbf {x} }
for some



m
×
n


{\displaystyle m\times n}
matrix



A


{\displaystyle A}
, called the transformation matrix of



T


{\displaystyle T}
. Note that



A


{\displaystyle A}
has



m


{\displaystyle m}
rows and



n


{\displaystyle n}
columns, whereas the transformation



T


{\displaystyle T}
is from





R


n




{\displaystyle \mathbb {R} ^{n}}
to





R


m




{\displaystyle \mathbb {R} ^{m}}
. There are alternative expressions of transformation matrices involving row vectors that are preferred by some authors.

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  1. Aleoa

    I Intuitive Linear Transformation

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  2. sweet springs

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    Lorentz transformation of electromagnetic field gives the relation ##E'=\gamma(E+v\times B)##. Lorentz force per unit charge is given as ##F=E+v\times B## without ##\gamma##. Don't we need coefficient ##\gamma## for F?
  3. arpon

    I How can we transform a Lagrangian to obtain a new set of equations of motion?

    Consider a Lagrangian: \begin{equation} \mathcal{L} = \mathcal{L}(q_1\, \dots\, q_n, \dot{q}_1\, \dots\, \dot{q}_n,t) \end{equation} From this Lagrangian, we get a set of ##n## equations: \begin{equation} \frac{d}{dt}\frac{\partial \mathcal{L}}{\partial \dot{q}_i} - \frac{\partial...
  4. Vital

    I Understanding the transformation of skewness formula

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  5. A

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  6. S

    I What is difference between transformations and automorphisms

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  7. Aleoa

    I Proving the Linear Transformation definition

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  8. Ben Geoffrey

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  9. T

    Fourier Transformation of ODE

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  10. C

    Field transformation under Conformal transformation

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  11. S

    A Transformation of a scalar field

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  12. Math Amateur

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  13. Math Amateur

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  14. Math Amateur

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  15. V

    A Understanding E-Field Transformation in Feynman II_26

    I have been learning SR from various sources. Most of the time from Feyman's Lectures but that's not the only place. In II_26 he gives the transformation for the E-field of a moving charge in the x direction under a standard Lorentz configuration. In Eqn 26.11 he derives a formula for the Ex...
  16. Math Amateur

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    I am reading Hugo D. Junghenn's book: "A Course in Real Analysis" ... I am currently focused on Chapter 9: "Differentiation on \mathbb{R}^n" I need some help with the proof of Proposition 9.2.3 ... Proposition 9.2.3 and the preceding relevant Definition 9.2.2 read as follows...
  17. Math Amateur

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  18. W

    Jacobian of a Lorentz transformation

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  19. Gene Naden

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  20. M

    Calculating Space-Time Coordinates for Derick's Drug Toss on Relativistic Train

    Homework Statement Derick is fleeing from the cops on a car on a relativistic train. At xr= 0.0m and tr =0.000s the cops at rest see Derick leaving the back of the train and head towards the front of the train on his relativistic car. The cops see him arrive at the front at xr = 1.875*10^5m...
  21. Gene Naden

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  22. Gene Naden

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  23. A

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  24. A

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  25. Gene Naden

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  26. A

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  27. L

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  28. T

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  29. D

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  30. Narasoma

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  31. C

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  32. MrGenetic

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  33. MrGenetic

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  34. T

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  35. V

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  36. A

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  37. L

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  38. Drakkith

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  39. Z

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  40. W

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  41. J

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  42. F

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  43. M

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  44. JTC

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  45. H

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  46. L

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  47. G

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  48. T

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  49. Q

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