Mike Helland wrote:

John Anderson

In physics, theories aren't falsified by "critical reasoning" unless they
are logically inconsistent. In that case, they are useless, since
anyone ought to see that they are inconsistent from the day they
appeared.

It would be nice if it worked that perfectly. The bottom line is that
sometimes with these things logical inconsistencies might take
sometime to uncover. As for General Relativity, I don't think anyone
can say that less than 100 years is the true test of time, and I don't
think its too hard to believe that it took that long (which is a
really short amount of time if you think about it).


How long should it take to find a logical insonsistencyin a theory based on
some very well understood mathematics?

Physical theories that are logically inconsistent get eliminated
before they get published.

End of story. You need to think a lot more about the logical
basis of science.


Experimental science decides among logically consistent theoriesthat explain
different results for the same experiment.

John Anderson

John Anderson

Physical theories that are logically inconsistent get eliminated
before they get published.

You are suggesting that we have obtained perfection in our ability to reason.

You are living in a dream world, Mr. Anderson.

Bilge,

And based on everything you know about QM, you aren't suspicious of
this line of reasoning?
No. General relativity is not a quantum theory and it doesn't bother
me in the least if a quantum theory requires a different description of
the universe in which spacetime itself ceases to be meaningful. I think
it's relatively clear that general relativity describes the universe
in terms of the four dimensions we observe.

We agree on more than we disagree on. I like your comment on spacetime
itself not being meaningful in Quantum. Do you realize that with my
theory, I explain why? Space is the same but time is different,
therefore, spacetime must be different?

One of the fundamental
questions associated with quantum gravity is whether or not a different
type of universe could even exist.

And do you understand that I answer this question by stating that the
universe contains more than one version of Time, and therefore, more
than one Nature?

Now, I can study this behaivor, perhaps to the point where I can
create a theory of formula to predict where this rock comes out and
how fast. And if the existing mathematics isn't sufficient, I could
probably even devise a system to explain the observations I'm making
of the rock coming out of the pond.
Sure, and with enough observations, you should be able to (1)
understand the physics of your hypothetical universe and (2) understand
the connection to this one.

How can you understand the physics of the other universe if all you
see if the results of it?

Let me parrellel he string theory.

A 1 dimensional string vibrating in 10 dimensions. I don't believe
that this is a 1 dimensional string, it is actually a 10 dimensional
violin that shares only 1 dimension with our plane of existence, and
therefore appears as a 1 dimensional string vibrating (ie, playing
music).

My violin example is only hypothetical, but do you understand the
point I'm making that there are distinct limits to our observation as
demonstrated by string theory? Do you understand my reasoning behind
only seeing the effects of the rock in our universe?

You are saying that I should be able to understand the physics of a
universe I only see results of. But thats just ridiculous. I don't
know if its being thrown back by some fundamental force of that
universe, of a green pony with one arm sticking out its head.

There is a point in our existence where rationality ends the ONLY
understanding that will result of that is understanding why it is that
we cannot understand what is after that point.

The fact that the two would be connected
begs the question of why you would consider two different universes,
though.

Its a hypothetical situation, bro'.

I could even write a theory to explain how the rock is going to come
out. But all that aside, I still have no idea how or why the rock was
thrown back from the other universe.
People used to have no idea why the sun rose and set or why lodestones
exhibited strange behaviour either, but lots of observations and study
explained those things.

I completely agree. But you're talking about things that are observed
by light. I'm talking about things that are not observed by light.
Your response here is a strawman.

By definition a GUT is a theory which unifies nature. We already have
separate thoeries which are adequate to describe nature and that only
requires two theories. The goal is to find one.

This sounds quite a bit like my theory stating that there are multiple
natures with their own GUTs and that the set of all the GUTs from all
the Natures of the universe is the GUT of the universe. No?

I'm thinking that we will need to clarify the term universe, if you're
willing to entertain my suggestion that QM and Classical Physics
shoudl be regarded as two different systems each requiring their own
unique unified theory.
Such a prospect would be very unsatisfactory for both physical and
philosophical standpoints.

How so? This is alot like saying the Computer Code you're running to
read this message cannot be logically seperated into an Operating
System and an Application that runs on the OS. We both know that this
is not true.

Mike Helland

Bilge,

If you study enough effects under a wide variety of circumstances, you can create a theory as to the cause.

Alot like how the cause of gravity is explained with General Relativity?

Thanks for all the info, Bilge.

Mike Helland:
Bilge,

If you study enough effects under a wide variety of circumstances, you can create a theory as to the cause.

Alot like how the cause of gravity is explained with General Relativity?

Find a globe. Now, start at the north pole and imagine two objects
which move at the same constant velocity along adjacent meridians.
Each object will see itself as moving at a constant velocity but the
other object will appear to accelerate away from and then back toward
it as the objets arrive at the south pole. However, by hypothesis,
neither object was acccelerating. Meridians are the straightest lines
possible on a sphere snd inertial motion along those lines gives the
appearance of acceleration. The same thing is true in four dimensions.
The geodesics in curved spacetime are just like geodesics on sphere,
except that instead of being a euclidean distance those geodesics
are the world lines of inertial objects.

Bilge,

Alot like how the cause of gravity is explained with General Relativity?
The geodesics in curved spacetime are just like geodesics on sphere,
except that instead of being a euclidean distance those geodesics
are the world lines of inertial objects.

Once again, I appreciate the lesson. But we disagree on why the
geodesics are curved in the first place. You say because of matter. I
say because of the gravity caused by matter.

You simply saying that they're curved and that the effects of that
curvature is what we call gravity is not going to change my mind that
what you call gravity is simply a perceived effect of gravity.

Unless, of course, you know of any experiments that could conclusively
show why spacetime is curved? Probably not, and if you could, it would
be rejected by everyone here "because physics is not supposed to tell
you why." Am I right?

So I have a choice to make, abandon my goal to understand what is
happening (this simply sounds intellectually dishonest to me) or
abandon "pure" physics as a means to reach my understanding. You have
told me to seek other studies. I get the picture.

I'm actually quite disappointed in those who claim to be scientists,
but your pope has spoken.

Mike Helland:

Once again, I appreciate the lesson. But we disagree on why the
geodesics are curved in the first place.

Why should geodesics _not_ be curved? "Flat" is just a way of
saying the curvature has a specific value - zero. Why should
nature choose a value and in particular, why should nature choose
zero over any other value?

You say because of matter. I say because of the gravity caused by matter.

You simply saying that they're curved and that the effects of that
curvature is what we call gravity is not going to change my mind that
what you call gravity is simply a perceived effect of gravity.

If you were inside of a completely closed box, could you determine
that you were falling in a gravitational field?

Unless, of course, you know of any experiments that could conclusively
show why spacetime is curved?

Can you give me any reason that spacetime should be flat?

Probably not, and if you could, it would be rejected by everyone
here "because physics is not supposed to tell you why." Am I right?

No, you are not right. Physics does tell you why. Your classical
bias doesn't permit you to accept the answer because the answer
doesn't fall into your preceived notion of what is an acceptable
answer. The fact is that the type of answer you seek is far more
complex and requires nature to be "unnatural", in that you want
some sort of complicated plan, rather than a very simple answer
in which nature didn't have to do anything at all.

So I have a choice to make, abandon my goal to understand what is
happening (this simply sounds intellectually dishonest to me) or
abandon "pure" physics as a means to reach my understanding. You have
told me to seek other studies. I get the picture.

You don't seem to be open enough to the idea that the physical
picture of the universe you acquired by age 10 or so might not
be the way the universe really works. That pretty much leaves
out pure physics as an option.

Have you ever asked yourself for a physical reason why the sum of the
squares of the two sides of a triangle should be equal to square of the
length of the hypotenuse? Probably not, or at least if you have, you are
probably satisfied with the answer. Why is that? It's no different than
what you are asking about gravity. I would suggest that you have never
examined your own preconceptions and asked yourself why you take those
things for granted.

I'm actually quite disappointed in those who claim to be scientists,
but your pope has spoken.

I'm quite disappointed that educational system hasn't taught people
to question their own preconceptions to the extent that they view
those of us that have as closed minded, You and other cranks who
describe yourselves as seeking "real answers" are in reality, seeking
answers in terms of your own preconceptions. You just can't believe
the universe can appear so complex, yet be reduced to some very
simple concepts because you cannot rid yourself of your bias against
anything your five senses won't detect.

Bilge,

Why should geodesics _not_ be curved? "Flat" is just a way of
saying the curvature has a specific value - zero. Why should
nature choose a value and in particular, why should nature choose
zero over any other value?

I haven't said that they are not curved. I am saying that they are not
curved for the reason you say they are curved. I tried to make this
clear in the following sentence:

You say because of matter. I say because of the gravity caused by matter.

You simply saying that they're curved and that the effects of that
curvature is what we call gravity is not going to change my mind that
what you call gravity is simply a perceived effect of gravity.
If you were inside of a completely closed box, could you determine
that you were falling in a gravitational field?

Are you saying: can I derive a logical conclusion about the cause of
the effects I perceive, despite not being able to witness the
mechanics of the effects that I perceive?

My answer to this is described by the pond. No. I say I have no idea.
If I only witness the results (effect) of an action and not the
mechanics (cause) I am in no position to say anything about what I
have not witnessed.

Unless, of course, you know of any experiments that could conclusively
show why spacetime is curved?
Can you give me any reason that spacetime should be flat?

Can you give me a reason why that question logically follows my
question?

I am admitting that spacetime is curved. You claim that matter is what
curves. I'm wondering if you have an experiment to prove this claim on
cause and effect.

No, you are not right. Physics does tell you why. Your classical
bias doesn't permit you to accept the answer because the answer
doesn't fall into your preceived notion of what is an acceptable
answer.

You are incorrect. My bias is Quantum, not classical.

I'm quite disappointed that educational system hasn't taught people
to question their own preconceptions to the extent that they view
those of us that have as closed minded

I agree with you. I don't think that applies to me however.

Your accusations of my close-mindedness are deserved, as I started by
accusing you of being closed minded. Thats always a recipie for more
misunderstanding. I apologize.

Mike Helland:

Can you give me a reason why that question logically follows my
question?

I am admitting that spacetime is curved. You claim that matter is what
curves. I'm wondering if you have an experiment to prove this claim on
cause and effect.

Light follows geodesics. Light follows a curved trajectory as it passes
by the sun. This is measured during an eclipse. The positions of stars
are shifted when compared with the same positions seen in the night sky.

Apparent
Normal position
position +
+
O sun
+
+
during
eclipse


No, you are not right. Physics does tell you why. Your classical
bias doesn't permit you to accept the answer because the answer
doesn't fall into your preceived notion of what is an acceptable
answer.

You are incorrect. My bias is Quantum, not classical.

In that case, curvature should not be a problem. Quantum field
theory makes use of curvature tensors for quantum fields. The
electromagnetic field strength tensor F^uv is the curvature tensor
for the electromagnetic field. Maxwell's equations a

d_{u}F^{uv} = j^{u}

along with the bianchi identity:

d^w F^uv + d^v F^wu + d^v F^uw = 0

The electromagnetic field strength tensor is obtained in exactly the
same way as the gravitational field strength tensor - from the commutator
of covariant derivatives. The equivalent quantity in gravity is the
riemann tensor.

On Fri, 8 Aug 2003, Bilge wrote:

Mike Helland:
You are incorrect. My bias is Quantum, not classical.

In that case, curvature should not be a problem. Quantum field
theory makes use of curvature tensors for quantum fields. The
electromagnetic field strength tensor F^uv is the curvature tensor
for the electromagnetic field. Maxwell's equations a

d_{u}F^{uv} = j^{u}

along with the bianchi identity:

d^w F^uv + d^v F^wu + d^v F^uw = 0

The electromagnetic field strength tensor is obtained in exactly the
same way as the gravitational field strength tensor - from the commutator
of covariant derivatives. The equivalent quantity in gravity is the
riemann tensor.

Sorry to keep hasseling you, but are you saying that in a Yang-Mills
theory, that the "curvature" that comes from using the gauge covariant
derivative is the field strength tensor?

I really need to recheck out Gauge Fields Knots & Gravity from our
library...

--
William C. Hogg