Re: Splitting the genres

In article <1139511524.700233.315090@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>,
genewardsmith@xxxxxxxxx says...

Robert Shaw wrote:

To begin with, what makes you believe there is a Mars? You can only
measure things at the precise space-time point you occupy, and Mars
isn't there.

I think the problem may be that Quinn is a formalist. He believes
"mathematics is the construction of lists of strings, each string
generated by performing one of several specified operations on a
previous string."

Sure.

Hence a mathematical model has no semantic content,
and cannot really be a model of physical reality in the way we want.

Hang on. Of course a mathematical model can be a model of reality.
Sure, it's semantic content is not fixed, the same equation could
describe a supernova and a rabbit population trend. But there's
nothing unusual about that.

What I do say is that [ignoring for the moment any very fundamental
speculations] a mathematical model can't BE the physical reality. Only
physical things can constitute physical reality. The mathematics is
just a set of strings by which we describe it.

On
the other hand, he *can* visualize three dimensional space, and hence
he can believe in the reality of three dimensions as a *physical*
totality.

I can visualise Minkowski space just fine too, and some other spaces.
And I can even visualise them as either abstract geometries or physical
ethers, just as I can visualise a circle as an abstract mathematical
object or a pencil line. The difference is that I don;t allow myself
to get confused as to which is which.

It's not a mathematical model, which would be lists of
strings. It's a Kantian intution of space, but unlike Kant Quinn thinks
that the space he is thus envisioning is real.

Where do you get this garbage from? For the purposes of examination, I
am willing to propose (or not) the hypothesis of a classical ether, or
a physical vacuum of some other kind, and examine its implications. I
don't ever mix up the mathematics with the physical stuff, though.
Either a theory proposes a physical spacetime or it doesn't. How come
YOU can't understand that?

Hence, Mars exists.
Spacetime does not and cannot exist, because we can't intuit it, we can
only have mathematical models, and model theory itself is still about
lists of strings.

No, it's perfectly valid to propose a physical spacetime. Just do it
or don't do it - stop trying to flip from one to the other in the same
supposed theory.

Either spacetime (as defined in a particular theory) is a physical
thing that can affect other physical things. Or it is not a physical
thing, and has no properties that can affect anything physical. Right?

- Gerry Quinn




.

Relevant Pages

  • Re: Splitting the genres
    ... "mathematics is the construction of lists of strings, ... Hence a mathematical model has no semantic content, ...
    (rec.arts.sf.written)
  • Re: Another Inconvenient Truth
    ... Han de Bruijn wrote: ... then what do you propose replace mathematics to ... As soon as we have an "exact" mathematical model, ... the physical reality being modeled identical. ...
    (sci.math)
  • Re: TRANSFINITE would be very weak if there was an alternate theory
    ... We can throw out all of the semantic baggage of mathematics, ... In such a system, "proofs" list in detail how, using only the string-manipulating rules defined, a group of strings "entails" another string. ... In this view, a "theory" is a group of strings such that all of the strings in the group are either "axioms" or are "theorems". ...
    (sci.math)
  • Re: Standard Topology on S^n ?
    ... Don't you think that these R^n things are extraordinary contortions, ... My spheres arise as follows. ... What confusion is there in mathematics about the numeric? ... assume they can ignore physical reality and take up any arbitrary abstract ...
    (sci.math)
  • johnreed take 1A - October 18, 2006
    ... The Universe and the Mathematics: ... mathematical model, both our questions, and the answer to our questions ... law, to act at a distance, by setting his first law object on an ...
    (sci.physics.relativity)