Re: Analysis of gas mode MM interferometer operation using standard SR formulae.

On Mon, 05 May 2008 22:08:42 -0500, Tom Roberts
<tjroberts137@xxxxxxxxxxxxx> wrote:

Surfer wrote:
Have a look at "Reduction of the interferometer observations" on Pages
213/214 of Miller's paper.
http://www.scieng.flinders.edu.au/cpes/people/cahill_r/Miller1933.pdf

To compensate for the effects of a linear temperature drift Miller
explains:

"A compensation for the shift is made by adding to the SUM of the
seventeenth column such a number that will make it equal to the SUM of
the first column and adding one-sixteenth, two-sixteenths, etc. of
this compensating number to the second, third, etc. columns; this
renders the axis of reference horizontal.

The word SUM lets us know that he is referring to the sum of 20 turns.
So the "forcing to zero" is only done ONCE every TWENTY FULL turns.

This is just plain wrong. Miller AVERAGED the values for each marker for
the 20 turns, and then applied that paragraph to the AVERAGES. Those
averages represent ONE turn.

It still remains the case that the "forcing to zero" is only done ONCE
every TWENTY FULL turns. That is to say, the process of averaging does
not do any such forcing.


Jerry misspoke slightly -- the result is forced to be NEAR zero at
markers 1 and 16 (it is near zero, not exactly zero, because the 20
values for marker "17" are not quite the same as the 20 values for
marker 1 [19 of them are identical]). But Miller then averaged the two
1/2 turns, and COPIED the first value to the 9th position. THAT makes
the resulting graph be periodic with period 1/2 turn,

Here are some counter examples:

Averaged raw data =
{10, 90, 10, 90, 10, 90, 10, 90, 10, 90, 10, 90, 10, 90, 10, 90, 10}
Output =
{10., 90., 10., 90., 10., 90., 10., 90., 10.}

Averaged raw data=
{10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150,
160, 170}
Output=
{10., 10., 10., 10., 10., 10., 10., 10., 10.}

Big swings in raw data values, but they do not cause outputs periodic
in half a turn.


and the zero is
constrained to be near the endpoints, but not constrained to be
precisely at an endpoint. And this is EXACTLY what his Fig 8 (my fig 1)
shows.


Here is a counter example:

Averaged raw data =
{30, 20, 10, 0, 10, 20, 30, 40, 30, 20, 10, 0, 10, 10, 20, 30, 30}
Output =
{30., 20., 10., 0., 10., 15., 25., 35., 30.}


You have spent more time grasping at straws than you would have spent
getting an education in basic error analysis.

Whatever my education, it doesn't alter the fact that your analysis of
Miller's experiment in:
http://www.arxiv.org/abs/physics/060823
is based on false premises.

FALSE PREMISE 1
=====================
The caption under Fig 3. says:

"The assumed-linear systematic drift from the data of Fig. 1.
The lines are between successive Marker 1 values and the points are
Marker 9. These markers are 180 degrees apart, so any real signal has
the same value for every corner and every point--the variations are
purely an instrumentation effect."

This statement is FALSE, because measurements at Marker 1 and Marker 9
were not made simultaneously. If we are to consider ANY real signal,
then we must be prepared to consider real signals that FLUCTUATE. The
value of any real signal that fluctuates would change between readings
at Marker 1 and Marker 9.
======================
FALSE PREMISE 2

At the top of page 6, you wrote:

data = signal(orientation) + systematic(time)

The key point is that signal(orientation) is independent of time,
and for each orientation (marker) it has the same value for every
turn of the interferometer within a given data run Therefore if the
data from the first turn is subtracted marker-by-marker from the
data of every turn, the result is completely independent of any
orientation dependence, and contains only systematic(time).


The above claims are false, because any real FLUCTUATING signal would
vary with orientation AND TIME.

So in particular, the claim that:

"Therefore if the data from the first turn is subtracted marker-by-marker
from the data of every turn, the result is completely independent of any
orientation dependence, and contains only systematic(time)."

is FALSE.
=======================

Consequently the main products of your analysis, including Figure 11,
have no validity.

-- Surfer




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