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The Doppler Shift Equation For An Accelerating Frame of Refe

 
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Shubee
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PostPosted: Sun Jun 22, 2008 6:25 am    Post subject: The Doppler Shift Equation For An Accelerating Frame of Refe Reply with quote

On Jun 19, 1:19 pm, Chalky <chalkys...@bleachboys.co.uk> wrote:

Quote:
At the present point in time I am interested specifically
in the redshift/distance relationship for a rigid linearly
accelerating reference frame.

The equation you seek is easy to derive. It is a part of my standard
reply for frequently asked questions regarding a constantly
accelerating frame of reference.

The equations for a coordinate system undergoing constant proper
acceleration are:

x=x'cosh(ct'/x')
t=(x'/c)sinh(ct'/x') for all x'>0.

Permit me to illustrate their meaning. Think of an accelerating
rocket. c is the speed of light. x' is a general position location in
the accelerating rocket. (Call x' and t' rocket coordinates if you
like). Believe it or not, in relativity, if a long rocket accelerates
without any part of the ship being compressed or stretched during its
motion, then an astronaut at the bottom of the rocket will feel a
greater acceleration than an astronaut at the tip of the rocket. This
force is given by the equation g(x')=-(c^2)/x'.

Many interesting problems can be solved in special relativity by first
learning how to interpret and use these three elementary equations.

Suppose a rocket ship, which looks like a long rod, begins to
accelerate at t=t'=0. Let’s say that the ship has a rest length of L.
(x=x' at t=0). Suppose that the tip of the rocket ship undergoes a
constant proper acceleration g. For that case, assign the tip of the
ship the fixed point x'_b =(c^2)/g. Then the bottom of the ship
undergoes a proper acceleration of g' =(c^2)/(x'_a) where x'_a = x'_b
- L. Every point on the accelerated ship is carrying a clock. If some
event happens on the ship, it will be at some x' with the clock at
that point reading time t'. According to the coordinates of the
stationary frame, the event will happen at point x at time t. All
clocks are synchronized to read zero time at the instant acceleration
begins.

From these equations, I shall derive the exact redshift/distance
equation for light that is moving from the bottom of the rocket to the
furthermost tip of the rocket. I propose the following strategy.

One helpful insight in physics is the observation that if we had a
constant gravitational field, then the equation for the Doppler shift
would be trivial. I reason as follows:

Let f be the initial frequency of a photon at some initial point in a
constant gravitational field. Suppose that the photon is moving
radially. Since the force felt by the photon is constant along its
path, the Doppler shift would depend only on the distance traveled by
the photon through the constant accelerative force. In this instance,
the Doppler shift equation for a photon traveling a distance x would
be

f' = fH(x).

If the photon would move an additional distance y, then

f'' = f'H(y).

Consequently, f''=fH(x+y) = fH(x)H(y) and we are left with the simple
functional equation

H(x+y) = H(x)H(y)

The only continuous solution for this equation is of the form

H(x) =exp (alpha x) where alpha is some constant.

Comparing this equation with Einstein’s approximation leads us to the
conclusion that alpha = -g/c^2.

Now for the more general problem of a photon moving radially in a
varying gravitational field where the accelerative force -g is a known
function of x, simply recall baby calculus and divide the photon path
into infinitely many infinitesimal layers, at least in the limit,
where the gravitational force is approximately constant at each layer.
The infinite product

f|(final) =f [exp g(x'1)dx'/c^2] [exp g(x'2)dx'/c^2]... [exp g(x'n)dx'/
c^2] would convert to the integral

f|(final) =f exp[ integral g(x')dx'/c^2 ]

where g(x') = -c^2 / x'

The limits of integration would be from x'= x'_a to x'= x'_b.

Remembering to divide g(x') by c^2, the exponential of the integral
that is to be evaluated between the limits of [c^2/g –L] to [c^2/g] is
easily computed to be 1-gL/c^2.

So f' = f (1-gL/c^2).

It is easy to check that this reasoning is correct. I shall now derive
the equation in a completely different way and without exploiting
Einstein's approximation. Consider the instantaneously co-moving
inertial frame of reference at the moment that a photon at the base of
the rocket (x'= x'_a) is emitted toward the tip (x'= x'_b). I will
first determine the time it takes for the photon to arrive, in
inertial coordinates, given that the front of the rocket (x'= x'_b) is
moving at a constant proper acceleration g. I shall then figure out
the final velocity from that.

From the perspective of the initial co-moving inertial reference frame

ct= L + c^2/g[ sqrt (1+(gt/c)^2) –1]

or equivalently,

1-gL/c^2 = sqrt (1+(gt/c)^2) - gt/c

At this point, I insert the well-known formula:

gt/c = sinh gt'/c where t' is the elapsed proper time for any clock at
x'_b.

Thus 1-gL/c^2 = exp (-gt'/c)

Now recall that v/c = tanh (gt'/c) is the very well-known formula for
the final velocity of a clock undergoing constant proper acceleration
g and recall that

arc tanh x = 1/2 ln [(1+x)/(1-x)] is always applicable for |v/c| < 1.

Consequently,

1-gL/c^2 = exp (-gt'/c) = sqrt [(1-v/c)/(1+v/c)], which again is the
correct factor in the Doppler shift equation.

Shubee
http://www.everythingimportant.org/relativity/special.pdf
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Dono
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PostPosted: Sun Jun 22, 2008 10:50 pm    Post subject: Re: The Doppler Shift Equation For An Accelerating Frame of Reply with quote

On Jun 21, 11:25 pm, Shubee <e.Shu...@gmail.com> wrote:
Quote:
On Jun 19, 1:19 pm, Chalky <chalkys...@bleachboys.co.uk> wrote:


I must commend you for trying to calculate something instead of
pushing (again) your crackpot paper.
Your computations are nevertheless incomplete and they produce the
incorrect results. Here are the complete calculations I did some time
ago:

http://www.savefile.com/projects/1046240

DvM gave me the clue for the first part (the one that uses the
Newtonian approximation of accelerated motion). I did the part using
hyperbolic motion.
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Dono
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PostPosted: Sun Jun 22, 2008 11:40 pm    Post subject: Re: The Doppler Shift Equation For An Accelerating Frame of Reply with quote

On Jun 21, 11:25 pm, Shubee <e.Shu...@gmail.com> wrote:

Quote:

1-gL/c^2 = exp (-gt'/c) = sqrt [(1-v/c)/(1+v/c)], which again is the
correct factor in the Doppler shift equation.


The correct formula is not 1-gL/c^2 but 1-gL/c^2+0.5(gL/c^2)^2 , if
you use the Newtonian approximation.
If you use the eqs of hyperbolic motion, the formula is even more
complicated, see my writeup.
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BURT
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PostPosted: Mon Jun 23, 2008 2:22 am    Post subject: Re: The Doppler Shift Equation For An Accelerating Frame of Reply with quote

On Jun 21, 10:25 pm, Shubee <e.Shu...@gmail.com> wrote:
Quote:
On Jun 19, 1:19 pm, Chalky <chalkys...@bleachboys.co.uk> wrote:

At the present point in time I am interested specifically
in the redshift/distance relationship for a rigid linearly
accelerating reference frame.

The equation you seek is easy to derive. It is a part of my standard
reply for frequently asked questions regarding a constantly
accelerating frame of reference.

The equations for a coordinate system undergoing constant proper
acceleration are:

x=x'cosh(ct'/x')
t=(x'/c)sinh(ct'/x') for all x'>0.

Permit me to illustrate their meaning. Think of an accelerating
rocket. c is the speed of light. x' is a general position location in
the accelerating rocket. (Call x' and t' rocket coordinates if you
like). Believe it or not, in relativity, if a long rocket accelerates
without any part of the ship being compressed or stretched during its
motion, then an astronaut at the bottom of the rocket will feel a
greater acceleration than an astronaut at the tip of the rocket. This
force is given by the equation g(x')=-(c^2)/x'.

Many interesting problems can be solved in special relativity by first
learning how to interpret and use these three elementary equations.

Suppose a rocket ship, which looks like a long rod, begins to
accelerate at t=t'=0. Let’s say that the ship has a rest length of L.
(x=x' at t=0). Suppose that the tip of the rocket ship undergoes a
constant proper acceleration g. For that case, assign the tip of the
ship the fixed point x'_b =(c^2)/g. Then the bottom of the ship
undergoes a proper acceleration of g' =(c^2)/(x'_a) where x'_a  = x'_b
- L. Every point on the accelerated ship is carrying a clock. If some
event happens on the ship, it will be at some x' with the clock at
that point reading time t'. According to the coordinates of the
stationary frame, the event will happen at point x at time t. All
clocks are synchronized to read zero time at the instant acceleration
begins.

From these equations, I shall derive the exact redshift/distance
equation for light that is moving from the bottom of the rocket to the
furthermost tip of the rocket. I propose the following strategy.

One helpful insight in physics is the observation that if we had a
constant gravitational field, then the equation for the Doppler shift
would be trivial. I reason as follows:

Let f be the initial frequency of a photon at some initial point in a
constant gravitational field. Suppose that the photon is moving
radially. Since the force felt by the photon is constant along its
path, the Doppler shift would depend only on the distance traveled by
the photon through the constant accelerative force. In this instance,
the Doppler shift equation for a photon traveling a distance x would
be

f' = fH(x).

If the photon would move an additional distance y, then

f'' = f'H(y).

Consequently,  f''=fH(x+y) = fH(x)H(y) and we are left with the simple
functional equation

H(x+y) = H(x)H(y)

The only continuous solution for this equation is of the form

H(x) =exp (alpha x) where alpha is some constant.

Comparing this equation with Einstein’s approximation leads us to the
conclusion that alpha = -g/c^2.

Now for the more general problem of a photon moving radially in a
varying gravitational field where the accelerative force -g is a known
function of x, simply recall baby calculus and divide the photon path
into infinitely many infinitesimal layers, at least in the limit,
where the gravitational force is approximately constant at each layer.
The infinite product

f|(final) =f [exp g(x'1)dx'/c^2] [exp g(x'2)dx'/c^2]... [exp g(x'n)dx'/
c^2] would convert to the integral

f|(final) =f exp[ integral g(x')dx'/c^2 ]

where g(x') = -c^2 / x'

The limits of integration would be from x'= x'_a to x'= x'_b.

Remembering to divide g(x') by c^2, the exponential of the integral
that is to be evaluated between the limits of [c^2/g –L] to [c^2/g] is
easily computed to be 1-gL/c^2.

So f' = f (1-gL/c^2).

It is easy to check that this reasoning is correct. I shall now derive
the equation in a completely different way and without exploiting
Einstein's approximation. Consider the instantaneously co-moving
inertial frame of reference at the moment that a photon at the base of
the rocket (x'= x'_a) is emitted toward the tip (x'= x'_b). I will
first determine the time it takes for the photon to arrive, in
inertial coordinates, given that the front of the rocket (x'= x'_b) is
moving at a constant proper acceleration g. I shall then figure out
the final velocity from that.

From the perspective of the initial co-moving inertial reference frame

ct= L + c^2/g[ sqrt (1+(gt/c)^2) –1]

or equivalently,

1-gL/c^2 = sqrt (1+(gt/c)^2) - gt/c

At this point, I insert the well-known formula:

gt/c = sinh gt'/c where t' is the elapsed proper time for any clock at
x'_b.

Thus 1-gL/c^2 = exp (-gt'/c)

Now recall that v/c = tanh (gt'/c) is the very well-known formula for
the final velocity of a clock undergoing constant proper acceleration
g and recall that

arc tanh x = 1/2 ln [(1+x)/(1-x)] is always applicable for |v/c| < 1.

Consequently,

1-gL/c^2 = exp (-gt'/c)  = sqrt [(1-v/c)/(1+v/c)], which again is the
correct factor in the Doppler shift equation.

Shubeehttp://www.everythingimportant.org/relativity/special.pdf

The Doppler shift for acceleration through space is energy effected by
changing Gamma; multiplied when toward light and divided downward when
away.

Mitch Raemsch
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Shubee
Guest





PostPosted: Tue Jun 24, 2008 1:23 am    Post subject: Re: The Doppler Shift Equation For An Accelerating Frame of Reply with quote

On Jun 23, 3:25 pm, Chalky <chalkys...@bleachboys.co.uk> wrote:
Quote:
On Jun 22, 10:58 am, Shubee <e.Shu...@gmail.com> wrote:

On Jun 19, 1:19 pm, Chalky <chalkys...@bleachboys.co.uk> wrote:

At the present point in time I am interested specifically
in the redshift/distance relationship for a rigid linearly
accelerating reference frame.

The equation you seek is easy to derive. It is a part of my standard
reply for frequently asked questions regarding a constantly
accelerating frame of reference.

The equations for a coordinate system undergoing constant proper
acceleration are:

x=x'cosh(ct'/x')
t=(x'/c)sinh(ct'/x') for all x'>0.

Permit me to illustrate their meaning. Think of an accelerating
rocket. c is the speed of light. x' is a general position location in
the accelerating rocket. (Call x' and t' rocket coordinates if you
like). Believe it or not, in relativity, if a long rocket accelerates
without any part of the ship being compressed or stretched during its
motion, then an astronaut at the bottom of the rocket will feel a
greater acceleration than an astronaut at the tip of the rocket.

Yes, I am aware of this conclusion. However, it appears to introduce a
contradiction when combined with another standard special relativistic
result relative to an accelerating observer; that he will remain
(relative to him) at an invariant distance from an origin located at g/
c^2 behind him.

First of all, your memory is faulty. g/c^2 doesn’t have the dimensions
of distance. But c^2/g does. Also, the result that you barely remember
is that if an observer has a head start on a photon, then the photon
will never catch up to the observer if the observer is accelerating at
a uniform acceleration g and if his initial head start distance is L c^2/g.

Quote:
Clearly another observer at that (inertial) origin cannot experience
accelerations of zero and infinity at the same time.

I believe that you’re confusing c^2/g with g/c^2. Those are two
different quantities. The first quantity has the dimensions of length.
The second has the dimensions of 1/length. In the coordinate system
given, no observer can be stationed at x'=0 because that point
represents a point of infinite acceleration.

It is important to note that there is no limit to the magnitude of
proper acceleration and however great a number you select for the
acceleration g, the resulting speed of an object will always be less
than the speed of light. In that sense, the speed of light can be
interpreted as representing infinite acceleration.

Quote:
This force is given by the equation g(x')=-(c^2)/x'.

I am afraid this formula doesn't make any sense to me. If the rocket
observer defines x' as distance from him, the formula tells him that
he must always experience infinite acceleration.

And it doesn’t make sense to me that you would want to change the
definition of rocket coordinates in midstream. There are good reasons
to read carefully. The choice for the point x'=0 to represent the
event horizon was completely arbitrary. But it does simplify the
math.

Quote:
Thanks for the subsequent advice but with this level of confusion at
the start, I was unable to follow the rest of your reasoning.

Do you remember the bottom line question that you asked?

“At the present point in time I am interested specifically
in the redshift/distance relationship for a rigid linearly
accelerating reference frame.”

I answered your inquiry directly.
I derived the equation:
f' = f (1-gL/c^2).

Do you understand that equation?

L is the length of the rocket.
c is the ordinary speed of light.
g is the acceleration at the top of the rocket.
f is the frequency of a photon emitted at the bottom of the rocket.
f' is the frequency of the photon when it’s received at the top of the
rocket.

Note that if the length of the rocket L approaches c^2/g, then the
Doppler shift approaches zero. Can you guess what the meaning of that
limit point is? It means that L = c^2/g is that critical head start
distance where light can never reach the accelerating observer at the
top of the rocket.

Shubee
http://www.everythingimportant.org/relativity/special.pdf
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Dono
Guest





PostPosted: Tue Jun 24, 2008 1:34 am    Post subject: Re: The Doppler Shift Equation For An Accelerating Frame of Reply with quote

On Jun 23, 6:23 pm, Shitbert <e.Shu...@gmail.com> wrote:

Quote:

I answered your inquiry directly.
I derived the equation:
f' = f (1-gL/c^2).

Do you understand that equation?

L is the length of the rocket.
c is the ordinary speed of light.
g is the acceleration at the top of the rocket.
f is the frequency of a photon emitted at the bottom of the rocket.
f' is the frequency of the photon when it’s received at the top of the
rocket.


Shitbert,

Any time you start selfpromotion you reagin the Shitbert name.
I have already shown that your derivation is wrong and so is your
result:

http://groups.google.com/group/sci.physics.relativity/msg/25453b760481476e?
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Dredd
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PostPosted: Sun Jun 29, 2008 6:23 pm    Post subject: Re: Is The Proper Acceleration of a Rigid Rod Possible? Reply with quote

On Jun 29, 8:01 pm, Tom Roberts <tjroberts...@sbcglobal.net> wrote:
Quote:
[...]

I'll answer the question in the subject: no.

In relativity, "rigid" is impossible. But one could construct a "rod"

.....


Quote:
Tom Roberts

You seems confused Sir

Relativity effects assume 100% rigidity
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Guest






PostPosted: Sun Jun 29, 2008 7:24 pm    Post subject: Re: Is The Proper Acceleration of a Rigid Rod Possible? Reply with quote

On Jun 29, 10:01 am, Tom Roberts <tjroberts...@sbcglobal.net> wrote:
Quote:
[...]

I'll answer the question in the subject: no.

In relativity, "rigid" is impossible. But one could construct a "rod"
out of a series of small atoms which are arranged in sequence along its
length, and each atom is given an appropriate proper acceleration so at
all times the proper distance between adjacent atoms is constant. This
is as close as one can come to "rigid". When one does this for
acceleration along the length of the rod, each atom along its length
must be given a different proper acceleration. This is known as Born
rigid motion.

So there is no "the" proper acceleration of a "rigid" rod. There must be
a different proper acceleration at each point along the rod.

Tom Roberts

The rod is extended in curved space. It's extension is curved.
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Tom Roberts
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PostPosted: Sun Jun 29, 2008 11:01 pm    Post subject: Re: Is The Proper Acceleration of a Rigid Rod Possible? Reply with quote

[...]

I'll answer the question in the subject: no.

In relativity, "rigid" is impossible. But one could construct a "rod"
out of a series of small atoms which are arranged in sequence along its
length, and each atom is given an appropriate proper acceleration so at
all times the proper distance between adjacent atoms is constant. This
is as close as one can come to "rigid". When one does this for
acceleration along the length of the rod, each atom along its length
must be given a different proper acceleration. This is known as Born
rigid motion.

So there is no "the" proper acceleration of a "rigid" rod. There must be
a different proper acceleration at each point along the rod.


Tom Roberts
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Shubee
Guest





PostPosted: Sat Jul 05, 2008 1:17 am    Post subject: Re: The Definition of Proper Acceleration Reply with quote

On Jul 2, 4:10 am, Chalky <chalkys...@bleachboys.co.uk> wrote:
Quote:
On Jun 30, 10:24 pm, Shubee <e.Shu...@gmail.com> wrote:

On Jun 30, 4:09 am, Chalky <chalkys...@bleachboys.co.uk> wrote:

On Jun 29, 2:30 pm, Shubee <e.Shu...@gmail.com> wrote:

On Jun 23, 3:25 pm, Chalky <chalkys...@bleachboys.co.uk> wrote:

On Jun 22, 10:58 am, Shubee <e.Shu...@gmail.com> wrote:
This force is given by the equation g(x')=-(c^2)/x'.

I am afraid this formula doesn't make any sense to me. If the rocket
observer defines x' as distance from him, the formula tells him that
he must always experience infinite acceleration.

The x' coordinate is defined to be the Lorentz invariant quantity

(x')^2 =x^2-(ct)^2

Well that formula doesn't make any sense either, since it tells us
that x' is independent of g.

The acceleration g is a function of x' so it doesn't have to appear
explicitly in the definition of x'. Here is a straightforward method
for finding that function.

Let x' = D represent a fixed point in the accelerating coordinate
system. Suppose D >0. Then

x^2 = D^2 + (ct)^2

Please note that x=x(t). Clearly, x(t) = D sqrt(1+ (ct)^2/D^2)
represents the motion of the point x' = D in terms of time t. Note
that x(0) = D.

Let b = c^2/D^2

Then x(t) = D sqrt(1+ bt^2).

Using baby calculus, we may expand sqrt(1+ bt^2) using the Maclaurin
series. Thus:

sqrt(1+ bt^2) = 1 + b(t^2)/2 - (b^2)(t^4)/8 + ...

So x(t) = D + (c^2/2D)t^2 - (c^4/8D^3)t^4 + ...

If time t is sufficiently small compared to c^2/2D, we may ignore the
fourth and all higher orders of t in the expansion.

Well none of this makes any sense either.

Perhaps you have forgotten that smooth mathematical functions can be
approximated by using the Maclaurin series.
http://mathworld.wolfram.com/MaclaurinSeries.html
Is there a chance that you have never studied freshman level
mathematics in any depth and that you only have false memories of
actually taking a course in calculus?

Quote:
We have already established from your placing of the accelerating
system origin at the event horizon of the accelerating observer, that
this places t=0 an infinite time in the past, in the inertial system.

Who is we? You haven't proven anything. Setting D=0 in the Lorentz
invariant equation D^2 =x^2-(ct)^2 only proves that x=ct or x=-ct.
Those two equations don't connect t=0 with the infinite past in any
significant way.

Quote:
Clearly infinity is never 'small' in comparison to a finite quantity.

And it's even clearer that you have never approximated the value of a
function in the neighborhood of a point.

Quote:
I have summarised where I think you have gone wrong at SPR. If you
want to address these issues please do so in a logical manner, not by
introducing higher and higher levels of mathematical abstraction.

I wouldn't say that freshman level mathematics is attaining a high
level of mathematical abstraction but I will affirm strongly that if
you can't even acknowledge that I agree with professional relativists
about the non-constant gravitational field in a uniformly accelerating
rocket (cf. Wolfgang Rindler, Relativity: Special, General, and
Cosmological pp. 71-73), then you need to ask questions about simpler
problems.

Shubee
http://www.everythingimportant.org/relativity/directory.htm
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BURT
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PostPosted: Sat Jul 05, 2008 1:32 am    Post subject: Re: The Definition of Proper Acceleration Reply with quote

On Jul 4, 5:17 pm, Shubee <e.Shu...@gmail.com> wrote:
Quote:
On Jul 2, 4:10 am, Chalky <chalkys...@bleachboys.co.uk> wrote:





On Jun 30, 10:24 pm, Shubee <e.Shu...@gmail.com> wrote:

On Jun 30, 4:09 am, Chalky <chalkys...@bleachboys.co.uk> wrote:

On Jun 29, 2:30 pm, Shubee <e.Shu...@gmail.com> wrote:

On Jun 23, 3:25 pm, Chalky <chalkys...@bleachboys.co.uk> wrote:

On Jun 22, 10:58 am, Shubee <e.Shu...@gmail.com> wrote:
This force is given by the equation g(x')=-(c^2)/x'.

I am afraid this formula doesn't make any sense to me. If the rocket
observer defines x' as distance from him, the formula tells him that
he must always experience infinite acceleration.

The x' coordinate is defined to be the Lorentz invariant quantity

(x')^2 =x^2-(ct)^2

Well that formula doesn't make any sense either, since it tells us
that x' is independent of g.

The acceleration g is a function of x' so it doesn't have to appear
explicitly in the definition of x'. Here is a straightforward method
for finding that function.

Let x' = D represent a fixed point in the accelerating coordinate
system. Suppose D >0. Then

x^2 = D^2 + (ct)^2

Please note that x=x(t). Clearly, x(t) = D sqrt(1+ (ct)^2/D^2)
represents the motion of the point x' = D in terms of time t. Note
that x(0) = D.

Let b = c^2/D^2

Then x(t) = D sqrt(1+ bt^2).

Using baby calculus, we may expand sqrt(1+ bt^2) using the Maclaurin
series. Thus:

sqrt(1+ bt^2) = 1 + b(t^2)/2 - (b^2)(t^4)/8 + ...

So x(t) = D + (c^2/2D)t^2 - (c^4/8D^3)t^4 + ...

If time t is sufficiently small compared to c^2/2D, we may ignore the
fourth and all higher orders of t in the expansion.

Well none of this makes any sense either.

Perhaps you have forgotten that smooth mathematical functions can be
approximated by using the Maclaurin series.http://mathworld.wolfram.com/MaclaurinSeries.html
Is there a chance that you have never studied freshman level
mathematics in any depth and that you only have false memories of
actually taking a course in calculus?

We have already established from your placing of the accelerating
system origin at the event horizon of the accelerating observer, that
this places t=0 an infinite time in the past, in the inertial system.

Who is we? You haven't proven anything. Setting D=0 in the Lorentz
invariant equation D^2 =x^2-(ct)^2 only proves that x=ct or x=-ct.
Those two equations don't connect t=0 with the infinite past in any
significant way.

Clearly infinity is never 'small' in comparison to a finite quantity.

And it's even clearer that you have never approximated the value of a
function in the neighborhood of a point.

I have summarised where I think you have gone wrong at SPR. If you
want to address these issues please do so in a logical manner,  not by
introducing higher and higher levels of mathematical abstraction.

I wouldn't say that freshman level mathematics is attaining a high
level of mathematical abstraction but I will affirm strongly that if
you can't even acknowledge that I agree with professional relativists
about the non-constant gravitational field in a uniformly accelerating
rocket (cf. Wolfgang Rindler, Relativity: Special, General, and
Cosmological pp. 71-73), then you need to ask questions about simpler
problems.

Shubeehttp://www.everythingimportant.org/relativity/directory.htm- Hide quoted text -

- Show quoted text -

Deceleration and rotation also create gravity according to Einstein's
Equivalence Principle.
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