.. _gramaldi:

===================
 GR24 and Amaldi16
===================

**A quest from Bingley to Glasgow in search of the truth of
gravitational waves**

How an old guy from a ski school, came to believe the big bang might not
have happened and attends an astrophysics conference in search of truth.

As I am not in academia, I listed my institution as *Académie Camp
Fortune, Chelsea, Quebec*, where I work as a ski instructor doing
practical experiments in gravity, in a low friction environment.

I am fortunate that this gives me a great deal of time to ponder the
mysteries of the universe.

Since returning from Glasgow, I have spent the summer trying to write
up why I went on this journey.

It is taking longer than expected as the conference itself has very
much helped focus my attention on the crux of this matter.

Central to the story is Professor Colin Rourke.  He sadly passed away
in December 2024.  It was his work that shaped my views on cosmology
and brought me to a belief that the waves in spacetime that we are
seeing may not be coming from colliding black holes.

In a 2018 discussion on black holes there is this fascinating comment
from Colin Rourke::

   There is another possible more important problem that I have with
   black holes.  The fundamental inertial drag hypothesis that explains
   the dynamics of galaxies needs every mass in the universe to have a
   well-defined rotation (or a well-defined inertial frame in which it is
   static).  But the current fiction is that a BH is a POINT SINGULARITY
   and therefore it has nothing to define its rotation.  I mention this
   problem in passing in the book, but I did not stress it because I did
   not want to murder yet another sacred cow.

Rather than murdering another sacred cow, this story asks if the
sacred cow is not in fact a mirror image of a grander beast?

It should be noted that a Kerr black hole does have angular momentum.
There is a parameter, a, the angular momentum per unit mass and cannot
exceed 1.0.

If two maximally rotating black holes merge there is nowhere for their
angular momentum to go but out into the universe.

If the angular momentum exceeds this the mathematics says it collapses
to a point, at which point, it's angular momentum disappears.  Or
rather, creates a ripple in spacetime, strong enough for us to see.

The Kerr solution is known to be the unique solution for a rotating
mass, if space is a vacuum.

Now the detection of gravitational waves is also the detection of the
aether that Michelson and Morley were persuing.  Space is not a
vacuum.  A rotating mass not only distorts the space-time around it,
but in turn that distortion of space-time becomes a gravitational
wave.  It's amplitude at a distance r, is 1/r times the original
amplitude.

So spacetime is not a vacuum, rotating objects make waves.  In the
case of binary pulsars, this should create a stable system with no
final inspiral.

We should also think about the curving of spacetime that mass creates
and ask the question, how exactly does mass curve spacetime?  In
short, it does this by rotating, hence sending off waves.

The rotations of all the atoms in a body?  A high frequency wobble
that all matter is bound to follow.

As promised another explanation for the observations is presented.

Just like in the black hole merger idea, we have a boundary in our
space time, the edge of our visible universe.

When a new body enters our visible universe we see it's entire
gravitational history in a very short period of time.

Imagine the waves given off by a black hole, that grows slowly by
acretion to say a million solar masses.  How long might this take? 

This explanation has the following in common with the merging of black
holes::

* We are seeing black holes

* the waves are shaped by the Kerr metric

* events have an inspiral, a peak and a ringdown

* we can estimate the mass involved in an event

* we expect co-incident gamma-ray bursts, depending on the mass involved

* the mass redshift degeneracy turns up as a mass blueshift degeneracy

* gravitational waves move according to the Sciama Principle

* the observation is a confirmation of Einstein's general relativity.  

In the new explanation::

* the masses are likely of the order of a million solar masses
* the shape of gamma-ray bursts and ringdown are related.
  
In the ringdown phase, the blue shift decreases rapidly.  The shape of
the curve allows two parameters, theta and phi to be estimated. These values
will also define the shape of any accompanying gamma-ray burst and
also the inspiral.

Rourke ends chapter 4 of The Geometry of the Universe with a
*coda*::

  Sciama's initiative to base a dynamical theory on Mach's
  principle as formulated in Sciama's principle, has never
  been followed up and this approach to dynamics remains
  dormant.  One of the aims of this book is to reawaken
  this approach.

It is my belief that the Sciama principle is the best explanation of
the gravitational waves that both the Pulsar Timing Array and the
LIGO, Virgo and Kagra detectors are seeing.

I have split this story into a number of sections, reflecting how my
understanding has evolved.  For some sections there is a corresponding
python module.

.. toctree::
   :maxdepth: 2

   bingley
   jodrell
   warwick
   anpftu
   birch
   gw150914
   gw170817
   glasgow
   jfc
   binary
   ringdown