Sum rule in integration: Difference between revisions

From formulasearchengine
Jump to navigation Jump to search
en>Vaxquis
Application to indefinite integrals: removed non-encyclopedic phrase "Since the integral is similar to a sum anyway, this is hardly surprising."
 
 
Line 1: Line 1:
Royal Votaw is my name but I never really liked that title. I am a manufacturing and distribution officer. What she loves doing is bottle tops collecting and she is trying to make it a occupation. For years she's been residing in Kansas.<br><br>My site: extended car warranty, [http://www.Zgraj.site90.com/members/profile/27819/IvMaxfield mouse click the next site],
{{see also|Introduction to special relativity}}
 
Following is a list of the frequently occurring equations in the theory of [[special relativity]].
 
== Postulates of special relativity ==
 
To derive the equations of special relativity, one must start with two postulates:
 
#The laws of physics are invariant under transformations between inertial frames.  Basically, the laws of physics will be the same whether you are testing them in a frame 'at rest', or a frame moving with a constant velocity relative to the 'rest' frame.
#The speed of light in a vacuum is measured to be the same by all observers in inertial frames.  So, if I shine a beam of light, and measure how fast it's going, and then start moving really fast, and then measure the speed of the light beam again, both measurements will produce the same result.
 
From these two postulates, all of special relativity follows.
 
In the following, the [[relative velocity]] ''v'' between two [[inertial frame]]s is restricted fully to the ''x''-direction, of a [[Cartesian coordinate system]].
 
==Kinematics==
 
===Lorentz transformation===
 
The following notations are used very often in special relativity:
 
;[[Lorentz factor]]
 
:<math> \gamma = \frac{1}{\sqrt{1 - \beta^2}}</math>
 
where β = ''v/c'' and ''v'' is the relative velocity between two [[inertial frame]]s.
 
For two frames at rest, γ = 1, and increases with relative velocity between the two inertial frames. As the relative velocity approaches the speed of light, γ → ∞. 
 
;[[Time dilation]] (different times ''t'' and ''t''' at the same position ''x'' in same inertial frame)
 
:<math> t' = \gamma t</math>
 
:{| class="toccolours collapsible collapsed" width="80%" style="text-align:left"
!Derivation of time dilation
|-
|
Applying the above postulates, consider the inside of any vehicle (usually exemplified by a train) moving with a velocity ''v'' with respect to someone standing on the ground as the vehicle passes.  Inside, a light is shone upwards to a mirror on the ceiling, where the light reflects back down.  If the height of the mirror is ''h'', and the speed of light ''c'', then the time it takes for the light to go up and come back down is:
 
:<math>t = \frac{2h}{c}</math>
 
However, to the observer on the ground, the situation is very different.  Since the train is moving by the observer on the ground, the light beam appears to move diagonally instead of straight up and down.  To visualize this, picture the light being emitted at one point, then having the vehicle move until the light hits the mirror at the top of the vehicle, and then having the train move still more until the light beam returns to the bottom of the vehicle.  The light beam will have appeared to have moved diagonally upward with the train, and then diagonally downward.  This path will help form two-right sided triangles, with the height as one of the sides, and the two straight parts of the path being the respective hypotenuses:
 
:<math>c^2 \left(\frac{t'}{2}\right)^2 = h^2 + v^2 \left(\frac{t'}{2}\right)^2</math>
 
Rearranging to get <math>t'</math>:
 
:<math>\left ( \frac{t'}{2} \right )^2 = \frac{h^2}{c^2 - v^2}</math>
:<math>\frac{t'}{2} = \frac{h}{\sqrt{c^2 - v^2}}</math>
:<math> t' = \frac{2h}{\sqrt{c^2 - v^2}}</math>
 
Taking out a factor of ''c'', and then plugging in for ''t'', one finds:
 
:<math> t' = \frac{2h}c \frac{1}{\sqrt{1 - \frac{v^2}{c^2}}} = \frac{t}{\sqrt{1 - \frac{v^2}{c^2}}}</math>
 
This is the formula for time dilation:
 
:<math> t' = \gamma t</math>
|}
 
In this example the time measured in the frame on the vehicle, ''t'', is known as the [[proper time]].  The proper time between two events - such as the event of light being emitted on the vehicle and the event of light being received on the vehicle - is the time between the two events in a frame where the events occur at the same location.  So, above, the emission and reception of the light both took place in the vehicle's frame, making the time that an observer in the vehicle's frame would measure the proper time.
 
;[[Length contraction]] (different positions ''x'' and ''x''' at the same instant ''t'' in the same inertial frame)
 
:<math>\ell' = \frac{\ell}{\gamma}</math>
 
:{| class="toccolours collapsible collapsed" width="80%" style="text-align:left"
!Derivation of length contraction
|-
|
Consider a long train, moving with velocity ''v'' with respect to the ground, and one observer on the train and one on the ground, standing next to a post.  The observer on the train sees the front of the train pass the post, and then, some time ''t&prime;'' later, sees the end of the train pass the same post.  He then calculates the train's length as follows:
 
:<math>\ell' = v t' \,</math>
 
However, the observer on the ground, making the same measurement, comes to a different conclusion.  This observer finds that time ''t'' passed between the front of the train passing the post, and the back of the train passing the post. Because the two events - the passing of each end of the train by the post - occurred in the same place in the ground observer's frame, the time this observer measured is the proper time.  So:
 
:<math>\ell = v t = v \left ( \frac{t'}{\gamma} \right ) = \frac{\ell'}{\gamma}</math>
|}
 
This is the formula for length contraction.  As there existed a proper time for time dilation, there exists a [[proper length]] for length contraction, which in this case is ''{{ell}}&prime;''.  The proper length of an object is the length of the object in the frame in which the object is at rest.  Also, this contraction only affects the dimensions of the object which are parallel to the relative velocity between the object and observer.  Thus, lengths perpendicular to the direction of motion are unaffected by length contraction.
 
;[[Lorentz transformation]]
 
:<math>x' = \gamma \left ( x - v t \right )</math>
:<math>y' = y \,</math>
:<math>z' = z \,</math>
:<math>t' = \gamma \left ( t - \frac{v x}{c^2} \right )</math>
 
:{| class="toccolours collapsible collapsed" width="80%" style="text-align:left"
!Derivation of Lorentz transformation using time dilation and length contraction
|-
|
Now substituting the length contraction result into the Galilean transformation (i.e. ''x'' = ''{{ell}}''), we have:
 
:<math>\frac{x'}{\gamma} = x - v t</math>
 
that is:
 
:<math>x' = \gamma \left ( x - v t \right )</math>
 
and going from the primed frame to the unprimed frame:
 
:<math>x = \gamma \left ( x' + v t' \right )</math>
 
Going from the primed frame to the unprimed frame was accomplished by making ''v'' in the first equation negative, and then exchanging primed variables for unprimed ones, and vice versa.  Also, as length contraction does not affect the perpendicular dimensions of an object, the following remain the same as in the Galilean transformation:
 
:<math>y' = y \,</math>
:<math>z' = z \,</math>
 
Finally, to determine how ''t'' and ''t&prime;'' transform, substituting the ''x''↔''x&prime;'' transformation into its inverse:
 
:<math>x = \gamma \left ( \gamma \left ( x - v t \right ) + v t' \right )</math>
:<math>x = \gamma \left ( \gamma x - \gamma v t + v t' \right )</math>
:<math>x = \gamma^2 x - \gamma^2 v t + \gamma v t' \,</math>
:<math>\gamma v t' = \gamma^2 v t - \gamma^2 x + x \,</math>
:<math>\gamma v t' = \gamma^2 v t + x \left ( 1 - \gamma^2 \right )</math>
 
Plugging in the value for γ:
 
:<math>\gamma v t' = \gamma^2 v t + x \left ( 1 - \frac{1}{1-\beta^2} \right )</math>
:<math>\gamma v t' = \gamma^2 v t + x \left ( \frac{1 - \beta^2}{1 - \beta^2} - \frac{1}{1-\beta^2} \right )</math>
:<math>\gamma v t' = \gamma^2 v t - x \left ( \frac{\beta^2}{1-\beta^2} \right )</math>
:<math>\gamma v t' = \gamma^2 v t - \gamma^2 \beta^2 x \,</math>
 
Finally, dividing through by γ''v'':
 
:<math>t' = \gamma \left ( t - \beta \frac{x}{c} \right )</math>
 
Or more commonly:
 
:<math>t' = \gamma \left ( t - \frac{v x}{c^2} \right )</math>
 
And the converse can again be gotten by changing the sign of ''v'', and exchanging the unprimed variables for their primed variables, and vice-versa.  These transformations together are the Lorentz transformation:
 
:<math>x' = \gamma \left ( x - v t \right )</math>
:<math>y' = y \,</math>
:<math>z' = z \,</math>
:<math>t' = \gamma \left ( t - \frac{v x}{c^2} \right )</math>
|}
 
;[[Velocity addition]]
 
:<math>V'_x=\frac{ V_x - v }{ 1 - \frac{V_x v}{c^2} }</math>
 
:<math>V'_y=\frac{ V_y }{ \gamma \left ( 1 - \frac{V_x v}{c^2} \right ) }</math>
 
:<math>V'_z=\frac{ V_z }{ \gamma \left ( 1 - \frac{V_x v}{c^2} \right ) }</math>
 
:{| class="toccolours collapsible collapsed" width="80%" style="text-align:left"
!Derivation of velocity addition
|-
|
The Lorentz transformations also apply to [[Differential (infinitesimal)|differential]]s, so:
 
:<math>dx' = \gamma \left ( dx - v dt \right )</math>
:<math>dy' = dy \,</math>
:<math>dz' = dz \,</math>
:<math>dt' = \gamma \left ( dt - \frac{v dx}{c^2} \right )</math>
 
The velocity is ''dx/dt'', so
 
:<math>\frac{dx'}{dt'}=\frac{ \gamma \left ( dx - v dt \right ) }{ \gamma \left ( dt - \frac{v dx}{c^2} \right ) }</math>
:<math>\frac{dx'}{dt'}=\frac{ dx - v dt }{ dt - \frac{v dx}{c^2} }</math>
:<math>\frac{dx'}{dt'}=\frac{ \frac{dx}{dt} - v }{ 1 - \frac{dx}{dt} \frac{v}{c^2} }</math>
 
Now substituting:
 
:<math>V_x = \frac{dx}{dt}\,\quad V'_x = \frac{dx'}{dt'}</math>
 
gives the velocity addition (actually below is subtraction, addition is just reversing the signs of ''V<sub>x</sub>'', ''V<sub>y</sub>'', and ''V<sub>z</sub>'' around):
 
:<math>V'_x=\frac{ V_x - v }{ 1 - \frac{V_x v}{c^2} }</math>
:<math>V'_y=\frac{ V_y }{ \gamma \left ( 1 - \frac{V_x v}{c^2} \right ) }</math>
:<math>V'_z=\frac{ V_z }{ \gamma \left ( 1 - \frac{V_x v}{c^2} \right ) }</math>
 
Also, the velocities in the directions perpendicular to the frame changes are affected, as shown above.  This is due to time dilation, as encapsulated in the ''dt''/''dt&prime;'' transformation.  The ''V&prime;<sub>y</sub>'' and ''V&prime;<sub>z</sub>'' equations were both derived by dividing the appropriate space differential (e.g. ''dy&prime;'' or ''dz&prime;'') by the time differential.
|}
 
== The metric and four-vectors ==
 
{{main|metric tensor|four-vectors}}
 
In what follows, bold sans serif is used for [[4-vector]]s while normal bold roman is used for ordinary 3-vectors.
 
;[[Inner product]] (i.e. notion of [[length]]):
 
:<math> \boldsymbol{\mathsf{a}} \cdot \boldsymbol{\mathsf{b}} =\eta (\boldsymbol{\mathsf{a}} , \boldsymbol{\mathsf{b}})</math>
 
where <math>\eta</math> is known as the [[metric tensor]].  In special relativity, the metric tensor is the [[Minkowski metric]]:
 
:<math>\eta = \begin{pmatrix} -1 & 0 & 0 & 0 \\ 0  & 1 & 0 & 0 \\ 0 & 0 & 1 & 0 \\ 0 & 0 & 0 & 1 \end{pmatrix}</math>
 
;[[Space-time interval]]
 
:<math>ds^2 = dx^2 + dy^2 + dz^2 - c^2 dt^2 = \begin{pmatrix} cdt & dx & dy & dz \end{pmatrix} \begin{pmatrix} -1 & 0 & 0 & 0 \\ 0  & 1 & 0 & 0 \\ 0 & 0 & 1 & 0 \\ 0 & 0 & 0 & 1 \end{pmatrix} \begin{pmatrix} cdt \\ dx \\ dy \\ dz \end{pmatrix}</math>
 
In the above, ''ds''<sup>2</sup> is known as the spacetime interval.  Another thing worth noting is that this inner product is invariant under the Lorentz transformation.  The invariance of inner product means the following:
 
:<math> \boldsymbol{\mathsf{a}}\cdot\boldsymbol{\mathsf{b}}  = \eta ( \boldsymbol{\mathsf{a}}' , \boldsymbol{\mathsf{b}}' ) = \eta \left ( \Lambda \boldsymbol{\mathsf{a}} , \Lambda \boldsymbol{\mathsf{b}} \right ) = \eta ( \boldsymbol{\mathsf{a}} , \boldsymbol{\mathsf{b}} )</math>
 
The sign of the metric and the placement of the ''ct'', ''ct''', ''cdt'', and ''cdt&prime;'' time-based terms can vary depending on the author's choice.  For instance, many times the time-based terms are placed first in the four-vectors, with the spatial terms following.  Also, sometimes η is replaced with −η, making the spacial terms produce negative contributions to the dot product or spacetime interval, while the time term makes a positive contribution.  These differences can be used in any combination, so long as the choice of standards is followed completely throughout the computations performed.
 
===Lorentz transforms===
 
It is possible to express the above coordinate transformation via a matrix.  To simplify things, it can be best to replace ''t'', ''t&prime;'', ''dt'', and ''dt&prime;'' with ''ct'', ''ct''', ''cdt'', and ''cdt&prime;'', which has the dimensions of distance.  So:
 
:<math>x' = \gamma x - \gamma \beta c t \,</math>
:<math>y' = y \,</math>
:<math>z' = z \,</math>
:<math>c t' = \gamma c t - \gamma \beta x \,</math>
 
then in matrix form:
 
:<math>\begin{pmatrix} c t' \\ x' \\ y' \\ z' \end{pmatrix} = \begin{pmatrix} \gamma & - \gamma \beta & 0 & 0 \\ - \gamma \beta & \gamma & 0 & 0\\ 0 & 0 & 1 & 0 \\ 0 & 0 & 0 & 1  \end{pmatrix}\begin{pmatrix} c t \\ x \\ y \\ z \end{pmatrix}</math>
 
The vectors in the above transformation equation are known as four-vectors, in this case they are specifically the position four-vectors.  In general, in special relativity, four-vectors can be transformed from one reference frame to another as follows:
 
:<math>\boldsymbol{\mathsf{a}}' = \Lambda \boldsymbol{\mathsf{a}}</math>
 
In the above, <math>\boldsymbol{\mathsf{a}}'</math> and <math>\boldsymbol{\mathsf{a}}</math> are the four-vector and the transformed four-vector, respectively, and Λ is the transformation matrix, which, for a given transformation is the same for all four-vectors one might want to transform. So <math>\boldsymbol{\mathsf{a}}'</math> can be a four-vector representing position, velocity, or momentum, and the same Λ can be used when transforming between the same two frames. The most general Lorentz transformation includes boosts and rotations; the components are complicated and the transformation requires [[spinor]]s.
 
===4-vectors and frame-invariant results===
 
Invariance and unification of physical quantities both arise from [[four-vector]]s.<ref>Dynamics and Relativity, J.R. Forshaw, A.G. Smith, Manchester Physics Series, John Wiley & Sons, 2009, ISBN 978-0-470-01460-8</ref> The inner product of a 4-vector with itself is equal to a scalar (by definition of the inner product), and since the 4-vectors are physical quantities their magnitudes correspond to physical quantities also.
 
{| class="wikitable"
! scope="col" width="100" | Property/effect
! scope="col" width="200" | 3-vector
! scope="col" width="200" | 4-vector
! scope="col" width="200" | Invariant result
|-
![[Space-time]] [[Event (relativity)|events]]
|3-position: '''r''' = (''x''<sub>1</sub>, ''x''<sub>2</sub>, ''x''<sub>3</sub>) <br />
<math> \mathbf{r} \cdot \mathbf{r} \equiv r^2 \equiv x_1^2 + x_2^2 + x_3^2 \,\!</math>
|4-position: '''X''' = (''ct'', ''x''<sub>1</sub>, ''x''<sub>2</sub>, ''x''<sub>3</sub>)
|<math> \boldsymbol{\mathsf{X}} \cdot \boldsymbol{\mathsf{X}} = \left ( c \tau \right )^2 \,\!</math> <br />
<math> \begin{align} & \left ( c t \right )^2 - \left ( x_1^2 + x_2^2 + x_3^2 \right ) \\
& = \left ( c t \right )^2 - r^2 \\
& = \chi^2 = \left ( c\tau \right )^2 \end{align} \,\!</math><br />
''τ'' = proper time <br />
''χ'' = proper length <br />
|-
![[invariant mass|Momentum-energy invariance]]
|
<math> \mathbf{p} = m\mathbf{u} \,\!</math>
 
3-momentum: '''p''' = (''p''<sub>1</sub>, ''p''<sub>2</sub>, ''p''<sub>3</sub>) <br />
<math> \mathbf{p} \cdot \mathbf{p} \equiv p^2 \equiv p_1^2 + p_2^2 + p_3^2 \,\!</math>
| 4-momentum: '''P''' = (''E/c'', ''p''<sub>1</sub>, ''p''<sub>2</sub>, ''p''<sub>3</sub>) <br />
<math> \boldsymbol{\mathsf{P}} = m \boldsymbol{\mathsf{U}} \,\!</math>
|<math> \boldsymbol{\mathsf{P}} \cdot \boldsymbol{\mathsf{P}} = \left ( m c \right )^2 \,\!</math>
<math> \begin{align} & \left ( \frac{E}{c} \right )^2 - \left ( p_1^2 + p_2^2 + p_3^2 \right ) \\
& = \left ( \frac{E}{c} \right )^2 - p^2 \\
& = \left ( mc \right )^2 \end{align} \,\!</math>
 
which leads to:<br />
<math> E^2 = \left ( pc \right )^2 + \left ( mc^2 \right )^2 \,\!</math>
 
''E'' = total energy <br />
''m'' = invariant mass <br />
|- style="border-top: 3px solid;"
!Velocity
| 3-velocity: '''u''' = (''u''<sub>1</sub>, ''u''<sub>2</sub>, ''u''<sub>3</sub>) <br />
<math> \mathbf{u} = \frac{\mathrm{d}\mathbf{r}}{\mathrm{d}t} \,\!</math>
| 4-velocity: '''U''' = (''U''<sub>0</sub>, ''U''<sub>1</sub>, ''U''<sub>2</sub>, ''U''<sub>3</sub>) <br />
<math>\boldsymbol{\mathsf{U}} =\frac{\mathrm{d}\boldsymbol{\mathsf{X}} }{\mathrm{d} \tau} = \gamma \left( c, \mathbf{u} \right) </math>
|<math> \boldsymbol{\mathsf{U}} \cdot \boldsymbol{\mathsf{U}} = c^2 \,\!</math><br />
|-
!Acceleration
| 3-acceleration: '''a''' = (''a''<sub>1</sub>, ''a''<sub>2</sub>, ''a''<sub>3</sub>) <br />
<math> \mathbf{a} = \frac{\mathrm{d}\mathbf{u}}{\mathrm{d}t} \,\!</math>
| 4-acceleration: '''A''' = (''A''<sub>0</sub>, ''A''<sub>1</sub>, ''A''<sub>2</sub>, ''A''<sub>3</sub>) <br />
<math>\boldsymbol{\mathsf{A}} =\frac{\mathrm{d}\boldsymbol{\mathsf{U}} }{\mathrm{d} \tau} = \gamma \left( c\frac{\mathrm{d}\gamma}{\mathrm{d}t}, \frac{\mathrm{d}\gamma}{\mathrm{d}t} \mathbf{u} + \gamma \mathbf{a} \right)</math>
|<math> \boldsymbol{\mathsf{A}} \cdot \boldsymbol{\mathsf{U}} = 0 \,\!</math><br />
|-
!Force
| 3-force: '''f''' = (''f''<sub>1</sub>, ''f''<sub>2</sub>, ''f''<sub>3</sub>) <br />
<math> \mathbf{f} = \frac{\mathrm{d}\mathbf{p}}{\mathrm{d}t} \,\!</math>
| 4-force: '''F''' = (''F''<sub>0</sub>, ''F''<sub>1</sub>, ''F''<sub>2</sub>, ''F''<sub>3</sub>) <br />
<math>\boldsymbol{\mathsf{F}} =\frac{\mathrm{d}\boldsymbol{\mathsf{P}} }{\mathrm{d} \tau} = \gamma m \left( c\frac{\mathrm{d}\gamma}{\mathrm{d}t}, \frac{\mathrm{d}\gamma}{\mathrm{d}t} \mathbf{u} + \gamma \mathbf{a} \right)</math>
|<math> \boldsymbol{\mathsf{F}} \cdot \boldsymbol{\mathsf{U}} = 0 \,\!</math><br />
|-
|}
 
==Doppler shift==
 
{{main|Doppler effect}}
 
General doppler shift:
 
:<math>\nu' = \gamma \nu \left ( 1 - \beta \cos \theta \right )</math>
 
Doppler shift for emitter and observer moving right towards each other (or directly away):
 
:<math>\nu' = \nu \frac{\sqrt{1 - \beta}}{\sqrt{1 + \beta}}</math>
 
Doppler shift for emitter and observer moving in a direction perpendicular to the line connecting them:
 
:<math>\nu' = \gamma \nu</math>
 
:{| class="toccolours collapsible collapsed" width="80%" style="text-align:left"
!Derivation of the relativistic Doppler shift
|-
|
If an object emits a beam of light or radiation, the frequency, wavelength, and energy of that light or radiation will look different to a moving observer than to one at rest with respect to the emitter.  If one assumes that the observer is moving with respect to the emitter along the x-axis, then the standard Lorentz transformation of the four-momentum, which includes energy, becomes:
 
:<math>\begin{pmatrix} \frac{E'}{c} \\ p'_x \\ p'_y \\ p'_z \end{pmatrix} = \begin{pmatrix} \gamma & - \gamma \beta & 0 & 0 \\ - \gamma \beta & \gamma & 0 & 0 \\ 0 & 0 & 1 & 0 \\ 0 & 0 & 0 & 1  \end{pmatrix} \begin{pmatrix} \frac{E}{c} \\ p_x \\ p_y \\ p_z \end{pmatrix}</math>
:<math>\frac{E'}{c} = \gamma \frac{E}{c} - \gamma \beta p_x</math>
 
Now, if
:<math>p_x = \| p \| \cos \theta</math>
 
where θ is the angle between ''p<sub>x</sub>'' and <math>\vec p</math>, and plugging in the formulas for frequency's relation to momentum and energy:
 
:<math>\frac{h \nu'}{c} = \gamma \frac{h \nu}{c} - \gamma \beta \left \Vert p \right \| \cos \theta = \gamma \frac{h \nu}{c} - \gamma \beta \frac{h \nu}{c} \cos \theta</math>
:<math>\nu' = \gamma \nu - \gamma \beta \nu \cos \theta = \gamma \nu \left ( 1 - \beta \cos \theta \right )</math>
 
This is the formula for the relativistic doppler shift where the difference in velocity between the emitter and observer is not on the x-axis. There are two special cases of this equation. The first is the case where the velocity between the emitter and observer is along the x-axis. In that case θ = 0, and cos θ = 1, which gives:
 
:<math>\begin{align}
\nu' & = \gamma \nu \left ( 1 - \beta \right )\\
& = \nu \frac{1}{\sqrt{1 - \beta^2}} \left ( 1 - \beta \right ) \\
& = \nu \frac{1}{\sqrt{\left ( 1 - \beta \right ) \left ( 1 + \beta \right ) }} \left ( 1 - \beta \right ) \\
& = \nu \frac{\sqrt{1 - \beta}}{\sqrt{1 + \beta}}
\end{align}</math>
 
This is the equation for doppler shift in the case where the velocity between the emitter and observer is along the x-axis.  The second special case is that where the relative velocity is perpendicular to the x-axis, and thus θ = π/2, and cos θ = 0, which gives:
 
:<math>\nu' = \gamma \nu</math>
 
This is actually completely analogous to time dilation, as frequency is the reciprocal of time.  So, doppler shift for emitters and observers moving perpendicular to the line connecting them is completely due to the effects of time dilation.
|}
 
==See also==
{{multicol}}
*[[Theory of relativity]]
*[[Special relativity]]
*[[General relativity]]
*[[List of physics formulae]]
*[[List of equations in classical mechanics]]
*[[Defining equation (physics)]]
*[[Defining equation (physical chemistry)]]
*[[Constitutive equation]]
{{multicol-break}}
*[[List of equations in classical mechanics]]
*[[Table of thermodynamic equations]]
*[[List of equations in wave theory]]
*[[List of equations in gravitation]]
*[[List of electromagnetism equations]]
*[[List of photonics equations]]
*[[List of equations in quantum mechanics]]
*[[List of equations in nuclear and particle physics]]
{{multicol-end}}
 
==References==
{{reflist}}
 
==Sources==
 
* ''Encyclopaedia of Physics (2nd Edition)'', R.G. Lerner, G.L. Trigg, VHC publishers, 1991, (Verlagsgesellschaft) 3-527-26954-1, (VHC Inc.) 0-89573-752-3
* ''Dynamics and Relativity'', J.R. Forshaw, A.G. Smith, Wiley, 2009, ISBN 978-0-470-01460-8
* ''Relativity DeMystified'', D. McMahon, Mc Graw Hill (USA), 2006, ISBN 0-07-145545-0
* ''The Cambridge Handbook of Physics Formulas'', G. Woan, Cambridge University Press, 2010, ISBN 978-0-521-57507-2.
* ''An Introduction to Mechanics'', D. Kleppner, R.J. Kolenkow, Cambridge University Press, 2010, ISBN 978-0-521-19821-9
 
[[Category:Special relativity]]
[[Category:Equations of physics]]
[[Category:Physics-related lists|Relativistic equations]]

Latest revision as of 02:03, 17 June 2013

DTZ's public sale group in Singapore auctions all forms of residential, workplace and retail properties, outlets, homes, lodges, boarding homes, industrial buildings and development websites. Auctions are at present held as soon as a month.

We will not only get you a property at a rock-backside price but also in an space that you've got longed for. You simply must chill out back after giving us the accountability. We will assure you 100% satisfaction. Since we now have been working in the Singapore actual property market for a very long time, we know the place you may get the best property at the right price. You will also be extremely benefited by choosing us, as we may even let you know about the precise time to invest in the Singapore actual property market.

The Hexacube is offering new ec launch singapore business property for sale Singapore investors want to contemplate. Residents of the realm will likely appreciate that they'll customize the business area that they wish to purchase as properly. This venture represents one of the crucial expansive buildings offered in Singapore up to now. Many investors will possible want to try how they will customise the property that they do determine to buy by means of here. This location has offered folks the prospect that they should understand extra about how this course of can work as well.

Singapore has been beckoning to traders ever since the value of properties in Singapore started sky rocketing just a few years again. Many businesses have their places of work in Singapore and prefer to own their own workplace area within the country once they decide to have a everlasting office. Rentals in Singapore in the corporate sector can make sense for some time until a business has discovered a agency footing. Finding Commercial Property Singapore takes a variety of time and effort but might be very rewarding in the long term.

is changing into a rising pattern among Singaporeans as the standard of living is increasing over time and more Singaporeans have abundance of capital to invest on properties. Investing in the personal properties in Singapore I would like to applaud you for arising with such a book which covers the secrets and techniques and tips of among the profitable Singapore property buyers. I believe many novice investors will profit quite a bit from studying and making use of some of the tips shared by the gurus." – Woo Chee Hoe Special bonus for consumers of Secrets of Singapore Property Gurus Actually, I can't consider one other resource on the market that teaches you all the points above about Singapore property at such a low value. Can you? Condominium For Sale (D09) – Yong An Park For Lease

In 12 months 2013, c ommercial retails, shoebox residences and mass market properties continued to be the celebrities of the property market. Models are snapped up in report time and at document breaking prices. Builders are having fun with overwhelming demand and patrons need more. We feel that these segments of the property market are booming is a repercussion of the property cooling measures no.6 and no. 7. With additional buyer's stamp responsibility imposed on residential properties, buyers change their focus to commercial and industrial properties. I imagine every property purchasers need their property funding to understand in value.

Following is a list of the frequently occurring equations in the theory of special relativity.

Postulates of special relativity

To derive the equations of special relativity, one must start with two postulates:

  1. The laws of physics are invariant under transformations between inertial frames. Basically, the laws of physics will be the same whether you are testing them in a frame 'at rest', or a frame moving with a constant velocity relative to the 'rest' frame.
  2. The speed of light in a vacuum is measured to be the same by all observers in inertial frames. So, if I shine a beam of light, and measure how fast it's going, and then start moving really fast, and then measure the speed of the light beam again, both measurements will produce the same result.

From these two postulates, all of special relativity follows.

In the following, the relative velocity v between two inertial frames is restricted fully to the x-direction, of a Cartesian coordinate system.

Kinematics

Lorentz transformation

The following notations are used very often in special relativity:

Lorentz factor
γ=11β2

where β = v/c and v is the relative velocity between two inertial frames.

For two frames at rest, γ = 1, and increases with relative velocity between the two inertial frames. As the relative velocity approaches the speed of light, γ → ∞.

Time dilation (different times t and t' at the same position x in same inertial frame)
t=γt

In this example the time measured in the frame on the vehicle, t, is known as the proper time. The proper time between two events - such as the event of light being emitted on the vehicle and the event of light being received on the vehicle - is the time between the two events in a frame where the events occur at the same location. So, above, the emission and reception of the light both took place in the vehicle's frame, making the time that an observer in the vehicle's frame would measure the proper time.

Length contraction (different positions x and x' at the same instant t in the same inertial frame)
=γ

This is the formula for length contraction. As there existed a proper time for time dilation, there exists a proper length for length contraction, which in this case is Template:Ell. The proper length of an object is the length of the object in the frame in which the object is at rest. Also, this contraction only affects the dimensions of the object which are parallel to the relative velocity between the object and observer. Thus, lengths perpendicular to the direction of motion are unaffected by length contraction.

Lorentz transformation
x=γ(xvt)
y=y
z=z
t=γ(tvxc2)
Velocity addition
V'x=Vxv1Vxvc2
V'y=Vyγ(1Vxvc2)
V'z=Vzγ(1Vxvc2)

The metric and four-vectors

Mining Engineer (Excluding Oil ) Truman from Alma, loves to spend time knotting, largest property developers in singapore developers in singapore and stamp collecting. Recently had a family visit to Urnes Stave Church.

In what follows, bold sans serif is used for 4-vectors while normal bold roman is used for ordinary 3-vectors.

Inner product (i.e. notion of length)
ab=η(a,b)

where η is known as the metric tensor. In special relativity, the metric tensor is the Minkowski metric:

η=(1000010000100001)
Space-time interval
ds2=dx2+dy2+dz2c2dt2=(cdtdxdydz)(1000010000100001)(cdtdxdydz)

In the above, ds2 is known as the spacetime interval. Another thing worth noting is that this inner product is invariant under the Lorentz transformation. The invariance of inner product means the following:

ab=η(a,b)=η(Λa,Λb)=η(a,b)

The sign of the metric and the placement of the ct, ct', cdt, and cdt′ time-based terms can vary depending on the author's choice. For instance, many times the time-based terms are placed first in the four-vectors, with the spatial terms following. Also, sometimes η is replaced with −η, making the spacial terms produce negative contributions to the dot product or spacetime interval, while the time term makes a positive contribution. These differences can be used in any combination, so long as the choice of standards is followed completely throughout the computations performed.

Lorentz transforms

It is possible to express the above coordinate transformation via a matrix. To simplify things, it can be best to replace t, t′, dt, and dt′ with ct, ct', cdt, and cdt′, which has the dimensions of distance. So:

x=γxγβct
y=y
z=z
ct=γctγβx

then in matrix form:

(ctxyz)=(γγβ00γβγ0000100001)(ctxyz)

The vectors in the above transformation equation are known as four-vectors, in this case they are specifically the position four-vectors. In general, in special relativity, four-vectors can be transformed from one reference frame to another as follows:

a=Λa

In the above, a and a are the four-vector and the transformed four-vector, respectively, and Λ is the transformation matrix, which, for a given transformation is the same for all four-vectors one might want to transform. So a can be a four-vector representing position, velocity, or momentum, and the same Λ can be used when transforming between the same two frames. The most general Lorentz transformation includes boosts and rotations; the components are complicated and the transformation requires spinors.

4-vectors and frame-invariant results

Invariance and unification of physical quantities both arise from four-vectors.[1] The inner product of a 4-vector with itself is equal to a scalar (by definition of the inner product), and since the 4-vectors are physical quantities their magnitudes correspond to physical quantities also.

Property/effect 3-vector 4-vector Invariant result
Space-time events 3-position: r = (x1, x2, x3)

rrr2x12+x22+x32

4-position: X = (ct, x1, x2, x3) XX=(cτ)2

(ct)2(x12+x22+x32)=(ct)2r2=χ2=(cτ)2
τ = proper time
χ = proper length

Momentum-energy invariance

p=mu

3-momentum: p = (p1, p2, p3)
ppp2p12+p22+p32

4-momentum: P = (E/c, p1, p2, p3)

P=mU

PP=(mc)2

(Ec)2(p12+p22+p32)=(Ec)2p2=(mc)2

which leads to:
E2=(pc)2+(mc2)2

E = total energy
m = invariant mass

Velocity 3-velocity: u = (u1, u2, u3)

u=drdt

4-velocity: U = (U0, U1, U2, U3)

U=dXdτ=γ(c,u)

UU=c2
Acceleration 3-acceleration: a = (a1, a2, a3)

a=dudt

4-acceleration: A = (A0, A1, A2, A3)

A=dUdτ=γ(cdγdt,dγdtu+γa)

AU=0
Force 3-force: f = (f1, f2, f3)

f=dpdt

4-force: F = (F0, F1, F2, F3)

F=dPdτ=γm(cdγdt,dγdtu+γa)

FU=0

Doppler shift

Mining Engineer (Excluding Oil ) Truman from Alma, loves to spend time knotting, largest property developers in singapore developers in singapore and stamp collecting. Recently had a family visit to Urnes Stave Church.

General doppler shift:

ν=γν(1βcosθ)

Doppler shift for emitter and observer moving right towards each other (or directly away):

ν=ν1β1+β

Doppler shift for emitter and observer moving in a direction perpendicular to the line connecting them:

ν=γν

See also

48 year-old Registered Nurse (Medical ) Rave from Pickering, enjoys to spend time individuals watching, new property for sale developers in singapore and cave diving. Finished a cruise liner experience that included passing by Chan Chan Archaeological Zone.

40 year old Supply and Circulation Manager Courtney from Aberdeen, has several pursuits including bmx, property developers in new project launch singapore and actions. Finds travel a wonderful experience after visiting Central Sikhote-Alin.

Trying to invest in Singapore Actual Property , or are you attempting to promote, hire, invest, buy buy a Singapore property ? Properly then, you may have come to the fitting place in your seek for Singapore properties. Here, we are going to aid you find your dream Singapore property from our market itemizing of 1000's of Singapore properties in our Singapore real property database.

Overseas particular person who want to buy/ purchase a Restricted residential property in Sentosa Cove can acquire fast observe approval from Singapore Land Dealing Unit. Overseas particular person who want to purchase/ acquire a Restricted residential property in Sentosa Cove can apply for a long term social visit move underneath this Scheme to facilitate entry into Singapore. Foreign individual who want to apply for permanent residency in Singapore can contact SLA or MAS permitted institutions. The place you're shopping for property which is below development, the Singapore Academyof Regulation will maintain a portion of the acquisition monies as stakeholders till the expiryof the defects legal responsibility interval supplied in the Agreement/Contract. D19) Hougang / Punggol / Sengkang Condominium Common Room with Aircon

A international individual (any one who isn't a Singapore citizen, Singapore Company, Singapore restricted liability partnership or a Singapore society) will still want approval from the Singapore Land Authority (SLA) to purchase land-titled property such as houses, bungalows and vacant plots of land. Housing Improvement Board Properties SINGAPORE NON-PUBLIC RESIDENTIAL PROPERTIES Singapore firm; Singapore society. We provide invaluable services to expats who are considering relocation to Singapore For every kind of Singapore property related providers, we're there to obtain your name. You are positive to get one of the best Singapore properties with our help. RE/MAX Singapore Singapore Residential Business and Industrial Singapore citizen; Singapore Land Authority Thomson Highway, Singapore

Nevertheless, additionally it is a foul investment decision to go in too early. For instance you buy a property near one of the new MRT station location at the Thomson line. Because it takes 10 years to be accomplished, you might need difficulties renting that place out to pay off your mortgage payments. In addition, 10 years is a long time when something can occur including recession, new properties being introduced, modifications in interest rates etc. All these can have an adversarial impact on your property funding.

First, there are generally more rental transactions than gross sales transactions, to permit AV to be determined for every property based on comparable properties. Second, actions in sale costs are extra unstable than rentals. Therefore, using rental transactions to derive the AV helps to maintain property tax extra steady for property owners. If you are shopping for or trying to hire a property. It's tiring to call up individual property agent, prepare appointments, coordinate timing and to go for individual property viewing. What most individuals do is to have a property agent representing them who will organize and coordinate the viewings for all of the properties out there based mostly in your requirements & most well-liked timing. Rent Property District 12 Lease Property District thirteen

The brokers say that many Chinese language patrons are also investing abroad so they can personal property close to major instructional establishments. Some are buying houses close to top faculties — despite the fact that their youngsters are so little they can not walk but. Greater than 80 % of rich Chinese need to ship their children overseas to school, based on the Hurun Report, a Shanghai-based mostly publication. Chinese language patrons sometimes used to pick up properties within the $1 to $5 million vary in New York, typically shopping for two and three at a time for funding purposes, the brokers mentioned. Monika Tu, a dealer at high-end real estate agency Black Diamondz Property Concierge in Sydney, says that over the previous yr mainland Chinese language have develop into 80 % of her firm's business. WCEGA Plaza & Tower

An insurance coverage that covers the reinstatement worth or outstanding loan, whichever is decrease, within the event that the property search singapore (view site…) it insures is destroyed by fire. The coverage does not embody dwelling renovations, moveable household contents and personal belongings. Mortgage Insurance Credit bureau checks (e.g., Good payment data for bank cards / previous or existing loans, no previous blemishes corresponding to discharged bankrupts) A sign by the financial institution of the quantity of mortgage that you are eligible for. Nonetheless, an AIP doesn't constitute a binding loan offer. Additional checks and situations may be imposed by the financial institution, and the phrases of the formal supply will even rely upon the property that you simply intend to buy. Freehold / leasehold (999 years / 99 years)

References

43 year old Petroleum Engineer Harry from Deep River, usually spends time with hobbies and interests like renting movies, property developers in singapore new condominium and vehicle racing. Constantly enjoys going to destinations like Camino Real de Tierra Adentro.

Sources

  • Encyclopaedia of Physics (2nd Edition), R.G. Lerner, G.L. Trigg, VHC publishers, 1991, (Verlagsgesellschaft) 3-527-26954-1, (VHC Inc.) 0-89573-752-3
  • Dynamics and Relativity, J.R. Forshaw, A.G. Smith, Wiley, 2009, ISBN 978-0-470-01460-8
  • Relativity DeMystified, D. McMahon, Mc Graw Hill (USA), 2006, ISBN 0-07-145545-0
  • The Cambridge Handbook of Physics Formulas, G. Woan, Cambridge University Press, 2010, ISBN 978-0-521-57507-2.
  • An Introduction to Mechanics, D. Kleppner, R.J. Kolenkow, Cambridge University Press, 2010, ISBN 978-0-521-19821-9
  1. Dynamics and Relativity, J.R. Forshaw, A.G. Smith, Manchester Physics Series, John Wiley & Sons, 2009, ISBN 978-0-470-01460-8