>>>>> Basically, you're right, global Lorentz symmetry breaks down in almost any
>>>>> kind of spacetime except Minkowski spacetime. In particular, it breaks down
>>>>> in the real world. There's a special cosmological reference frame in which
>>>>> the CMBR is isotropic and the "fixed stars" appear to be roughly at rest.
>>>>> Other frames analogous to SR's inertial frames can't be defined at all.
>>>>>
>>>>> This is the reason I wish that global Lorentz symmetry wasn't taught in
>>>>> courses in special relativity. You just end up having to unlearn it when you
>>>>> get to general relativity, and unlearning things is harder than learning
>>>>> them. Especially because the professor usually doesn't explicitly say "we
>>>>> lied to you in the previous class".
>>>>>
>>>>> -- Ben
>>>> 
>>>> I wonder why every layman with some mathematical intuition is 
>>>> considered to be "a crank" and "a crackpot" 
>>>
>>> Every layman with some mathematical intuition who thinks that
>>> physics is a branch of mathematics (like you obviously do), and
>>> thinks he knows better, is a crank - by definition. I know that
>>> sounds unfair to you, but that's the way it goes on this side of the
>>> planet.
>>>
>>> Dirk Vdm
>> 
>> Your "definition" defines many people who made original contributions
>> to physics as being cranks.
> 
> Show me one layman who thinks that physics is a branch of
> mathematics and thinks he knows better, who "made original
> contributions to physics".
> By the way, on this side of the planet, the following original
> contributions are considered to be outside the realm of physics:
>   https://home.deds.nl/~dvdm/dirk/Physics/Fumbles/FollowsImmediately.html
>   https://home.deds.nl/~dvdm/dirk/Physics/Fumbles/ReligionRelativity.html
>
> Dirk Vdm

Physics is a branch of mathematics, of course. Every exact science is,
and no science more so than physics. You can draw a tree with math at
the root. Physics branches directly from mathematics. Chemistry is
probably a branch of physics. Being a branch of does not mean being
inferior. It only means being less fundamental. Probably you know what
a tree is in graph theory? You might have built a "Tree Generator"
sometime in the past, before your attention focused on permutations.
If I were a physicist, I would keep it secret, because of the
embarrassment of Big Bang Theory.

You better take math seriously if you want to come somewhere with
physics. If you were a little bit better at math you would have
recognized that I have given proof of the fact that Relativity cannot
be valid in elliptic space. Instead your comments were that I "...know
*nothing* about the subject". Proving that Relativity cannot be valid
in elliptic space not bad for someone who "knows *nothing* about the
subject". Probably you have never heard of elliptic geometry. I doubt
you have a formal education status of any significance. Are there
universities in Belgium?

Keep this in mind: my proof only refers to the finiteness of straight
lines in finite space, so the proof holds for any finite space. There
can be no velocity symmetry in a finite space. On the other hand: there
would be no CMBR in infinite space. So the choice is yours.

I don't believe CMBR is "echo of Big Bang". Big Bang Theory is
NONSENSE, so CMBR must have a different origin. I just want to show
that your theories are inconsistent.

By the way, I didn't know that Belgium lies on the southern hemisphere.
I admit that the way the country is governed suggests it is on the
southern hemisphere, but to my best knowledge it lies north of the
equator.