Re: Inflationary Theory ; I'm confused
From: TomGee (lvlus_at_hotmail.com)
Date: 02/18/05
- Next message: Art Deco: "Re: Why do orchestras tune to oboes?"
- Previous message: Art Deco: "Re: Why do orchestras tune to oboes?"
- In reply to: george_at_briar.demon.co.uk: "Re: Inflationary Theory ; I'm confused"
- Next in thread: George Dishman: "Re: Inflationary Theory ; I'm confused"
- Reply: George Dishman: "Re: Inflationary Theory ; I'm confused"
- Messages sorted by: [ date ] [ thread ]
Date: 18 Feb 2005 08:22:47 -0800
george@briar.demon.co.uk wrote:
> TomGee wrote:
> > George Dishman wrote:
> > >
> > > I'm not sure why you include the word "parallel". We
> > > live in a 4D universe, three dimensions describing space
> > > and one for time.
> > >
> > >
> > Yes, I know, so why would AE make up another one just like ours?
It
> > boggled my imagination to think that he ignored the fact you just
> > pointed out, and so did all the scientists who have mentioned his
> > claim. Dumb, isn't it? Or maybe you know why he made up another
> one?
> > I just assumed his was a parallel one to ours since he ignored our
4d
> > universe.
>
> If you are referring to GR then he didn't make up any
> other universe, it describes _our_ universe. He didn't
> deal with any "parallel" universes AFAIK, certainly he
> didn't like QM and I doubt he would have liked the MWI.
>
> Of course it's possible you are referring to some
> comments he made that I haven't yet come across. If so
> a pointer would be appreciated.
>
I appreciate your point. I ascribed the term "parallel" on my own to
his explanation of curved space as printed in several publications
through the years. I never read where he said it was the same universe
as ours. I assumed it was another one since everyone already knew ours
is a 4d universe. What I read seemed to strongly infer a second
universe.
More recently, Stephen Hawking wrote in his book, "A Brief History Of
Time", page 24, that "It is often helpful to think of the four
coordinates of an event as specifying its position in a
four-dimensional space called space-time. It is impossible to imagine
a four-dimensional space." Here, even Hawking refers to s-t as if it
were a parallel U.
>
>
> > > The idea of "moving through space" implies some sort of
> > > static condition of space which is the Newtonian view
> > > that relativity discarded.
>
>
I see no such implication because objects move through space all the
time in our everyday world, which seems will happen even though
everything in the universe is always moving through space. However,
having said that, my model does claim that dark matter is essentially
static in space. Waves move through space, and so does visible matter,
but invisible matter stays in place in space.
And once again I note that you refer to classical physics as being
"discarded", as in rejected, by Relativity, although many here claim
they do not act as if they still believe that.
>
>
> > > He means that if you view the
> > > world as four-dimensional, each particle or object can
> > > be considered as moving through it at a fixed rate.
>
>
But Hawking said that is impossible. But, if it wasn't, I assume you
mean above "at a fixed rate" IN TIME but not necessarily at a fixed
rate of speed, no?
>
>
> > > The
> > > spatial axes are orthogonal to the time axis as well as
> > > each other so if you are at rest in your chosen inertial
> > > frame then all the motion is along the time axis.
> > >
>
>
Yes, I know all that, but my contention is that it is only possible to
do all that with the math construct which is space-time, and not,
according to Hawking, in reality.
>
>
> > I do view our world as 4d, as do you, but I don't believe his
claim.
> > Oh, you mean like in space-time? But s-t is a math construct that
> > serves to let us measure time and distance for objects so that we
can
> > calculate their world lines.
>
> All of physics consists of mathematical models of the
> world around us. Ohm's Law says voltage equals current
> times resistance. Ohm's Law is a mathematical model of
> a resistor, it isn't actually a resistor. Relativity is
> no different in this respect.
>
> > So AE's 4d universe is imaginary?
>
> No, like all others, his theories are descriptive and
> to be quantitative (i.e. useful), they are mathematical.
> What they attempt to describe is what is real.
>
> > Then
> > why does almost everyone believe it is a real place, and that
moving
> > through time is the same as moving through space?
>
> That is a philosophical point of view regarding our
> universe which is fairly easy to conclude from the
> mathematical model.
>
>
Yes, quite so. Thank you.
>
>
> It is less easy but more accurate
> to visualise the whole 4D manifold with eveything in
> it as a single structure. In this view I am a spiral
> line (round the Sun once a year) with some thickness
> hopefully about 70 years long and "now" is a point
> along that line.
>
>
Hmmm.... How is that more accurate than s-t?
>
>
> > > To put it in lay terms, if you stand still you will
> > > still get older - you are moving forward in time. Look
> > > up "four-velocity" for better explanations than I can
> > > offer.
> >
> > George, we move forward in time whether we're still or moving,
> everyone
> > knows that.
>
> Exactly. It also follows that different paths from
> one event (point in spacetime) to another may have
> different lengths, hence it is easy to understand
> the Twins Paradox. Clocks flown around the world
> (and many other experiments) have demonstrated this
> effect is quite real.
>
>
But here again you are mixing math with reality. We know that
different paths from an event may have different lengths, but that
knowledge is based on the Principle of Equivalence and not on s-t.
math. If it was based on math, we would have to believe that s-t is a
real place.
>
>
> > How does the rocketship on the surface of Earth move
> > through the curved space of Earth, as AE said?
>
> This is the way I think of it though it's a personal
> view. If, like me, you have trouble thinking in 4D,
> you'll need to use a little imagination ;-)
>
> First think of a slice through the Earth at the equator.
> The Earth is a 2D circle which is red in the centre
> and has a thin blue and brown edge. Now think of that
> extended in time as a cylinder which is red in the
> centre and blue/brown on the surface. An object free-
> falling from space would form a curved line approaching
> the cylinder until it hits the surface, say on a brown
> bit (land, not sea).
>
> At that point the surface forces
> it off the path it would have taken had it been able to
> continue falling to the centre. Thereafter the path of
> the object is continually being pushed off these curved
> lines
>
>
Which curved lines, George?
>
>
> and it is forced to lie along the surface of the
> cylinder.
>
>
As the cylinder moves through time, yes, but the cylinder is imaginary,
George, and so the rocketship is not really moving through the curved
space of the earth, is it? Everyone knows that while it sits on Earth,
it then is also moving through time, as is the planet and all of us on
it, but that does not mean it is moving through the curved space of
Earth.
Was not this then another one of the Great Scientist's Great Jokes on
us?
Or was it just another one of those theories that don't work but are so
complicated few if any can understand it much less explain it (like his
complex math of his static universe theory)?
>
>
> These curved lines are a family of geodesics
> if I understand the term correctly (which is in doubt!).
>
>
And geodesics is a math construct relating to the geometry of curved
surfaces.
TomGee
- Next message: Art Deco: "Re: Why do orchestras tune to oboes?"
- Previous message: Art Deco: "Re: Why do orchestras tune to oboes?"
- In reply to: george_at_briar.demon.co.uk: "Re: Inflationary Theory ; I'm confused"
- Next in thread: George Dishman: "Re: Inflationary Theory ; I'm confused"
- Reply: George Dishman: "Re: Inflationary Theory ; I'm confused"
- Messages sorted by: [ date ] [ thread ]
Relevant Pages
|
