Dark Matter soon to be found !

The BBC has just reported that the search for dark matter is reaching a crux http://www.bbc.co.uk/news/science-environment-24733131 as measurements are now sensitive enough to have a high chance of finding it, if it exists.  I don't think it will be found, and now that a result is expected, it should start to change the direction of big physics when it is not.

As the article says "Dark matter is thought to make up 27% of the Universe. But astronomers have only been able to infer its existence through the gravitational effects it has on visible matter in the Universe". Surely it is much more reasonable to look for a gravitational explanation for the phenomenon, than to seek stuff that does not absorb, emit, have temperature or any other detectable characteristics.

We know that gravitational mass and inertial mass are the same thing.  I am also hanging my hat on the assumption that gravity is not a real force, but a fictitious force like centrifugal force.  If so it means that another set of physicists trying to reconcile gravity with the three fundamental forces are sort of wasting their time.  So if we have a system comprising a horizontal perfectly smooth table with a hole in the centre, a string through it holding a mass underneath connecting to a mass on the table, when the upper mass orbits the hole at a speed giving equilibrium, we have tension on the string caused by two fictitious forces balancing each other.  Tension in the upper part is centripetal force causing the upper mass to change its direction twice every revolution.  The equal and opposite lower-string tension is what is traditionally called the reaction force of the Earth opposing gravity's force, but is in fact the string accelerating the lower mass (F = m a) (though it appears stationary) at a rate of 9.81m/s^2 upwards.  Everything sitting on the surface of the Earth is experiencing a push upwards which amounts to the same thing.

This means, as I understand it from L2 Physics, that we are in a rotating (non-inertial) frame of reference (not the Earth rotating, that is irrelevant, I mean the whole of spacetime).  I expect that general relativists know this very well.  The quandary is that our environment is shaped such that the distance between ourselves and any recumbent antipodeans is not changing even though our relative acceleration is -19.62m/s^2.

The reference point is the centre of the Earth, the thing that is bending spacetime locally to result in this behaviour.  So the question is either (a) are three spatial + one time (3S+T) dimensions enough, and time is real enough to enable gravity, or (b) is a fourth spatial dimension (4S+T) required, as I have been arguing for a while now.  My reading of the subject so far tells me (a) that there cannot be a fourth large spatial dimension, or the inverse square law would have to be inverse-cube law, which it isn't, and (b) that physics doesn't need time, except to deal with entropy.  Well I'm sorry but you can't have it both ways.

If GR already explains how masses accelerating away from each other can also not be changing their distance apart, then surely the role of time is fundamental, and surely the shape of the Universe should be something that can be described in some way.  I look forward to seeing it.

Meantime I wait for the news that dark matter is made of cheese . . .

Silver Hammer Man

Inflation is an important topic to address.  Any model needs to include it, as the evidence from the CMB makes the fact of it generally accepted, yet it requires several leaps of faith to do so.  For that very short period of time everything exceeded the speed of light, and then it ceased abruptly.  I’ve not studied it very deeply at all yet but am still intrigued by how such a force or impulse could exist and then cease so momentarily, and even when the force subsided the speed thus imparted to all masses should surely have made the whole lot explode.

The obvious retort is that as everything was so close, gravity was very strong and reined in a runaway expansion.  But this was before the laws had settled down: and anyway I can’t use gravity to explain itself.  Fortunately.

The quick answer is that during inflation the shape of the universe was unfolding.  I would rather call it a deployment, like the unfurling of solar panels, antenna arrays and instruments on a newly-launched spacecraft.  Pre-deployment, it fits into its launch shroud and has been given spin of about 1Hz for stability, and post-deployment is 3-axis stabilised, often around a gyro system using magnetic bearings for contact-free rotation, the flywheels spinning at around 20k rpm I seem to recall.  But for the 4-D toroidal universe the idea of an inflating flotation ring is also apt.

Sam has already dubbed the Big Bang the ‘Big Spin’.  Well first came the release of the enormous bubble of energy in an unstable form, and immediately after, its inflation to a form which gave the universe its shape and stability, which included conversion of most of the energy into rotational potential energy.  This model requires mass to carry moment of inertia, so would have to include that mass condensed by this stage.  So in a flash we have a 4-D flywheel of rotating spacetime with which masses engage to store energy losslessly.  Masses can’t exceed the speed of light, and electromagnetic radiation flies around at the speed of light (or would if the medium wan’t still opaque).  What is the nature of the engagement of spacetime with EM energy and mass?

Maxwell’s equations are cited as the four most significant ever.  He also determined that visible light is EM radiation because his speed calculation matched its measured speed, and thereby predicted other forms of EM energy, verified soon after by Helmholtz and Hertz.  ε₀ and μ₀ define the spacetime engagement relationship of the electric and magnetic components respectively, and in EM radiation these components can’t exist separately.  But how does mass engage with spacetime?  It has to be fundamental, and we can recall Maxwell found that 1/c² = ε₀μ₀.  Sure thing, mass can’t go faster than c.  The harder it is pushed, the more its inertia increases to oppose further acceleration.  Spacetime has a grip on all masses, noticeable only as their speed becomes relativistic.

At first I thought c was a barrier to the rotating universe idea, as a radius would be reached where v = c, and spoil the party. However it is clearly central to it.  This is a big relief, to consider c as a central property of the rotation rather than a barrier to it.  c is central to everything.

There are other fundamental properties of spacetime.  It is elastic, so the elasticity will have a definable value.  Yet it is also apparently unbreakable.  This links to another mystery I need an answer to – how is it that mass, which so readily converts to energy in an ordinary star (OK very slowly) or in the accretion disc around a black hole (up to 10% conversion I believe) becomes so stable once it has entered the event horizon?  The simple answer is that whether it is in mass or energy form it is still equivalent stuff that contributes to the black hole effective mass.  But energy doesn’t show properties of mass elsewhere.  Interesting things, black holes.

Words coming together

It has been difficult to discuss gravity without everyday things like rubber sheets, whirling objects on strings etc, and previous attempts to summarise used too many of these.  But I've been inspired to try again by articles in New Scientist discussing progress, or lack of it, in big physics.  This time it worked, and I am submitting an essay on the subject to the Gravity Research Foundation, March 2013. This way, it will be published only if it does well, and can be safely ignored otherwise.  At least it's a stake in the ground for me, and a reference point if I dare to request serious comments.
Just an "as if" model, but offering a way of thinking about the fundamental cause of gravity, the requirement for the fourth spatial dimension and a bit of justification for this, the expansion of the universe, dark energy, dark matter, a potential prediction for the reduction of G with time, and the reason that gravity has never been related to the three fundamental forces of nature.
But I think we can leave inflation for another time . . .