On Tuesday, April 30, 2019 at 5:08:34 AM UTC-6, beda pietanza wrote:
>
> Il giorno domenica 17 aprile 2016 01:48:41 UTC+2, Gary Harnagel ha scritto:
> >
> > On Saturday, April 16, 2016 at 9:11:10 AM UTC-6, Pentcho Valev wrote:
> > >
> > >
https://www.youtube.com/watch?v=oZWGBYDBoGw
> > >
> > > According to Nima Arkani-Hamed, (11:49) spacetime is doomed, there
> > > is no such thing as spacetime fundamentally, but, on the other hand,
> > > (21:41) spacetime is a logical consequence of Einstein's postulate
> > > that there is a maximum speed which is exactly the same for
> > > everybody, no matter how they are moving. But since the consequence
> > > is nonexistent and doomed, the postulate from which it has been
> > > deduced is false, isn't it?
> >
> > No, because the postulate is experimentally verified.
>
> postulate cannot be verified by experiments,
Whatever gave you such an unrealistic idea? Of COURSE, for example,
the invariance of the speed of light can be determined by experiment.
> from experiments you may pustulate some law, verifications don't prove,
> only falsefication can be definitive
There is no "proving" in physics, there is only confirmation (verification)
of refutation. But you have the situation backwards: the claim that the
speed of light is affected by the motion of the source or receiver has
been soundly refuted.
> > “No, no, you’re not thinking: you’re just being logical” – Niels Bohr
> >
> > > Logic does not allow the combination "true postulate, wrong
> > > consequence".
> >
> > If "logic" deduces space-time from P2, and space-time is false, but P2
> > is true, there is something wrong with your logic. This is only
> > logical.
> >
> > Either space-time is true or there is another postulate besides P2
> > which is used to deduce space-time that is false.
>
> there cannot be any postulate meant to falsify another postulate.
>
> they are assumed apriori.
So you believe that if you postulate that the sky is green, then it is
impossible to refute that? That is REALLY nuts!
> You need a theory to show that another theory is false.
No, all I need is a MEASUREMENT to refute a theory or a postulate.
> According to many the ether theory is a better model than spacetime to
> describe the universe.
Who are these "many"? They certainly aren't scientists.
> So they had postilate the existence of a ether to explain all, and in
> the ether model spacetime have no place.
In experimental measurement, the ether has no place, and spacetime is
just a model. It helps to conceptualize reality, but don't get too
attached to it:
“we can ask ourselves whether there is a raw precursor to the fabric of
spacetime – a configuration of the strings of the cosmic fabric in which
they have not yet coalesced into the organized form that we recognize
as spacetime. – Brian Greene, The Elegant Universe
"Everyone in string theory is convinced...that spacetime is doomed. But
we don't know what it's replaced by." – David Gross