My discussion with George Ellis
Yuri
Dear Dr Ellis,
First of all I would like reminding to you one quote from famous neurophysiologist Warren McCulloch, known for his work on the foundation for certain brain theories and his contribution to the cybernetics movement .
In the last century he wrote:
''As I see what we need first and foremost is not correct theory, but some
theory to start from, whereby we may hope to ask a question so that we will
get an answer, if only to the effect that our notion was entirely
erroneous. Most of the time we never even get around to asking the question
in such a form that it can have an answer."(Discussion with John von Neumann
John von Neumann Collected works, Volume 5,p.319)
It was about mind - body relationship and brain function
My question is the following:
I think this is applicable to modern physics?
I put forward 3 questions:
1) 4D space-time?
2) Gravity as a fundamental force?
3) 3 fundamental dimensional constants(G, c, h)?
My attempts to get answers see my essay
http://fqxi.org/community/forum/topic/1413
Ellis
1) 4D space-time? -- yes!
2) Gravity as a fundamental force? -- of course: but it's not a force like other forces, it's an expression of spacetime curvature, because of the principle of equivalence. Its the gravitational field (the Weyl tensor) that is more fundamental.
3) 3 fundamental dimensional constants(G, c, h)? -- well it's the dimensionless constants that really count. The "Living Review" by J-P Uzan is great on the topic: see here
Ellis
I have read your essay and still do not understand the set of numbers you give above. It is completely unclear what they refer to. Nevertheless I have two comments:
1. Your theory seems mainly numerological. I can't see what the underlying theory is that is supposed to lead to those numbers. Is it based in M theory, or general relativity, or loop quantum gravity, or what?
2.Your proposal is I think a form of cyclic universe. But no one has yet provided an unproblematic mechanism for a bounce between cycles, despite many attempts to do so.I did not see any mechanism presented in your essay that will resolve this problem (which is one I once spent many years thinking about).
Ellis
You don't provide a coherent theory, just a set of numerological statements. Additionally those are dimensional statements, and so entirely based in the choice of units. You can get any other result by changing the units, so they have no physical meaning.
Yuri
All scientific community used as basic Planck units.
My approach close to John Moffat proposal a variable speed of light approach to cosmological problems, which posits that G/c is constant through time, but G and c separately have not been. Moreover, the speed of light c may have been much higher during early moments of the Big Bang.
Ellis
John Moffat is a serious scholar, but he got the varying speed of light effect wrong. What he proposed was not a physical effect, it was just a change of coordinates. It can be eliminated by a change to more suitable coordinates.
Yuri
In my approach in duration cosmological time
Appendix 2 Cosmological values of mass
Mp =10^-24; 10^-24; 10^-24
Me =10^-28; 10^-28; 10^-28
Mpl=10^-4; 10^-4; 10^-4
Mhbl=10^16; 10^16; 10^16
See Scale invariance http://en.wikipedia.org/wiki/Scale_invariance
Scaling law has not been canceled.
Ellis
Moffat's later bimetric theory was OK, it was his first varying speed of light theory that was wrong. I did not see in your essay that you are proposing a bimetric theory.
There has been a huge amount of work on the possibility of varying constants since Gamov. Please see for example J P Uzan et al here and links therein: there are many constraints on such theories. You'll need to tie in to this literature in order to be taken seriously nowadays.
That is my final comment on your essay on this thread.