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plant
2014-Sep-01, 02:16 PM
would this be an accurate description of reality?

..... that the universe is made of stretchable spacetime , and filled with infinitely extended probability waves of 'particles' that posess certain arbitrary properties that make them more or less likely to interact with each other.....

is there anything more to it?

antoniseb
2014-Sep-01, 03:05 PM
I'm going to say no, that is not a useful description of reality, in that there are not scientifically precise definitions of many of the words and phrases used in it. For example, what does stretchable mean when talking about spacetime? Why the single quotes around particles? Those in themselves makes the description seem useless. Can you take the description and get a result from it? I'm thinking no. So then, how would it be accurate, since it doesn't point in much of a direction at all?

John Mendenhall
2014-Sep-01, 03:56 PM
The Wiki article is here:

http://en.m.wikipedia.org/wiki/Reality

Really.

WayneFrancis
2014-Sep-01, 05:02 PM
would this be an accurate description of reality?

..... that the universe is made of stretchable spacetime , and filled with infinitely extended probability waves of 'particles' that posess certain arbitrary properties that make them more or less likely to interact with each other.....

is there anything more to it?

that looks like word salad to me. Reality is that which is real and exists. If you are trying to sum up physics in 1 line then it is a bit of an ask. There is tones more to it. If there wasn't you wouldn't have people spending their whole lives learning about just small aspects of "reality"

Jeff Root
2014-Sep-01, 06:20 PM
I understand what plant is trying to do, and I think it is a
reasonable attempt.

To the extent that the description *is* accurate, it would be
useful to him as a conceptual picture of the physical composition
of the Universe.

The word "particles" is in quotes because plant expects that
"particles" are actually "extended probability waves", which we
refer to as "particles". It is beyond me to say whether that is
correct or not, but it does NOT appear to conflict with what I
have read of quantum mechanical descriptions.

-- Jeff, in Minneapolis

profloater
2014-Sep-01, 06:58 PM
would this be an accurate description of reality?

..... that the universe is made of stretchable spacetime , and filled with infinitely extended probability waves of 'particles' that posess certain arbitrary properties that make them more or less likely to interact with each other.....

is there anything more to it?It's just a description of an idea. It's a familiar idea about an interpretation of the macroworld we experience directly, and as an idea it cannot be accurate in the way you want it to be. "A strong, skilled man can drive a six inch nail into a piece of wood in one hammer blow" is that accurate? Is it less accurate than talking about the interactions involved?

Jeff Root
2014-Sep-01, 07:44 PM
profloater,

I understood plant's description of physical reality better
than I understand your reply. Let's say I agree that a strong,
skilled man can drive a six-inch nail into a piece of wood in one
hammer blow. I say it is an accurate statement, and that it is
no less accurate than talking about the interactions involved.
Where does this line of reasoning go next?

-- Jeff, in Minneapolis

profloater
2014-Sep-01, 09:26 PM
well I was being cryptic because there has been so much stuff on reality and where it might really lie. I feel the basic and widely held view that we are brain based with consciousness based inside our brain, is enough to justify the statement that reality is what we think it is and to extend that is a belief issue. I am agnostic about the explanation for external reality. The fact that I live with beliefs very similar to all the ones who say they do not need belief to know about reality, does not change this fundamental agnosticism. We model reality but to assume a one to one mapping from our model to external reality should be a recognised assumption. That's all. I don't really understand why some find that so objectionable, it seems basic if you accept we are brain based and only linked to the outside by our senses. The fact that so many prefer to believe in supernatural explanations should make us pause to realise we within science or logic can never prove them wrong.

profloater
2014-Sep-01, 09:41 PM
so what I mean in relation to the OP is that it is a description of an interpretation but it is hubristic to call it a simple definition of reality. You might see in my signature quote from KenG that I agree with him on this issue. We are very good at making templates to make sense of our manifold experiences.

Strange
2014-Sep-01, 10:02 PM
is there anything more to it?

Even if I accept Jeff's very generous interpretation of what you mean then, yes there is a lot more to it.

There are several things that can "stretch" space-time. These need to be quantified. The effects of this "stretching" then need to be quantified.

There are many different types of particles, with a large number of intrinsic properties (charge, spin, mass, color, ...). These need to be quantified and their interactions described.

The "infinitely extended probability waves" need to be calculated.

And so on.

Jeff Root
2014-Sep-02, 02:17 AM
You are focusing on the concept of "reality", when I'm pretty
sure that isn't even essential to plant's question. Just omit
the word "reality". plant is asking, "Is this description
accurate? Is it complete?"

When he asks "is there anything more to it?" he clearly means
at the same level of detail. Obviously one could go into endless
details about the properties of each of the different particles,
how they interact, how they can combine in different ways,
producing different mineral systems and geological structures
or atmospheric phenomenae or stellar fusion or living things.
But none of that is what he asked about. He suggested that
spacetime and matter-energy (described by QM as some kind
of "waves" but more commonly referred to as "particles") are
the basic components of everything, and asked if that is
correct, or if there is anything else not covered by those
concepts.

As far as I know, they cover everything, though many people
would of course say that some kind of spiritual ingredient is
essential.

-- Jeff, in Minneapolis

Strange
2014-Sep-02, 06:56 AM
Even at the same level it is incomplete. No mention of movement, force, energy, acceleration. These could all be included at an equally trivial level. If you are not going to include those simple bu important classical concepts, why bother with more advanced concepts like "probability waves" or general relativity. Charge, spin and mass are more fundamental and, in everyday life, more significant than probability waves.

So the more I think about it... Is it accurate: no. Is it complete: definitely not.

plant
2014-Sep-02, 11:58 AM
thank you for all your replies....

i guess i didn't think about 'force' - because i thought this was either due to warping of spacetime (gravity), or the interaction of particles (other fundamental forces).
again, acceleration as not 'fundamental' is it? perhaps momentum is more so but composed of mass and velocity (distance/time) ... and since mass presumably relates to particles interaction or non-interaction with the Higgs boson/ field... (and additional relativistic mass?)...
I guess 'spin' should be included as fundamental?

i'm trying to arrive at a 'true' (albeit reductionist) description of the universe at it's fundamental level (as we understand it today- knowing it as an approximation) - something that i could explain to my 8 yr old son who asks deep and mystical questions like "what is an electron?", "what is the universe made of".

Or.... if not "realism" should i be explaining it from the 'instrumentalist' point of view... e.g.. something like "The world is a lot more mysterious than it looks to the naked eye. We have theories that predict things and are therefore useful, and other theories that don't do much and are discarded. Over time, our theories can be tested and get more and more accurate. The theories tell us how to manipulate symbols in such a way to improve our lives, but say nothing about what is actually going on. Its mysterious and we probably won't ever get to the bottom of it.".

Strange
2014-Sep-02, 12:15 PM
Maybe it depends on what you mean by "accurate". Sticking to classical theory (Newton's laws of motion and gravity) is more accurate in that it allows you to use simple mathematics to make accurate predictions and come up with some surprising and elegant results (like why all weights fall at the same speed).

Your "high level summary" is based on more accurate theories but is vague to the point of completely losing that accuracy.


i'm trying to arrive at a 'true' (albeit reductionist) description of the universe at it's fundamental level (as we understand it today- knowing it as an approximation) - something that i could explain to my 8 yr old son

I admire your motivation for this. But the problem with trying to do it "bottom up" like this is that you have to throw away all the useful detail that makes those "fundamental" ideas work. I'm concerned that you might just confuse the poor kid!

Len Moran
2014-Sep-02, 12:27 PM
Or.... if not "realism" should i be explaining it from the 'instrumentalist' point of view... e.g.. something like "The world is a lot more mysterious than it looks to the naked eye. We have theories that predict things and are therefore useful, and other theories that don't do much and are discarded. Over time, our theories can be tested and get more and more accurate. The theories tell us how to manipulate symbols in such a way to improve our lives, but say nothing about what is actually going on. Its mysterious and we probably won't ever get to the bottom of it.".

We will never get to the bottom of it because science cannot test any extrapolation of a verified predictive scientific model to a realm outside of the means in which the conception and verification of the model took place. So even the most "fundamental" scientific predictive model will never actually be fundamental because we will never scientifically be able to separate the model from the means with which it was conceived and verified. The best that we can do is to invoke a philosophical conception of realism that makes an unprovable assumption regarding the correspondence between the scientific model and what that model may represent outside of our involvement.

plant
2014-Sep-02, 12:37 PM
i know what you mean.... but i guess you have to start somewhere? what about this???

"There are these types of particles (which by the way are not little billiard balls but more like probability waves), which experience these types of forces to different degrees.
As to why there are these particular particles and not some other particles?.. we don't know.
As to why some forces are stronger than others?.. we don't know.
We name these things 'mass' or 'charge' or 'spin' or but these English words don't have anything to do with what these attributes are- they are just labels.
We manipulate these symbols using algebra and it seems to generate approximations of the 'right' answers...".
We are not necessarily smart enough to ever find out the 'truth'...

Strange
2014-Sep-02, 12:38 PM
i know what you mean.... but i guess you have to start somewhere? what about this???

"There are these types of particles (which by the way are not little billiard balls but more like probability waves), which experience these types of forces to different degrees.
As to why there are these particular particles and not some other particles?.. we don't know.
As to why some forces are stronger than others?.. we don't know.
We name these things 'mass' or 'charge' or 'spin' or but these English words don't have anything to do with what these attributes are- they are just labels.
We manipulate these symbols using algebra and it seems to generate approximations of the 'right' answers...".
We are not necessarily smart enough to ever find out the 'truth'...

I'm sure that will satisfy an 8 year old! (At least it might stop him asking questions :))

DaveC426913
2014-Sep-02, 01:38 PM
Perhaps rephrase the question as:

"Describe existence in 50 words or less."

That way, you'll get responses where people have been forced to decide to constitutes to most salient information.

Ken G
2014-Sep-02, 03:21 PM
"The world is a lot more mysterious than it looks to the naked eye. We have theories that predict things and are therefore useful, and other theories that don't do much and are discarded. Over time, our theories can be tested and get more and more accurate. The theories tell us how to manipulate symbols in such a way to improve our lives, but say nothing about what is actually going on. Its mysterious and we probably won't ever get to the bottom of it."This seems a reasonable statement to me, though I would like to reframe that last part, which sounds like pessimism or giving up, with "It's mysterious and our goal is to get deeper into it, but not to the bottom because it is not at all clear that there is a bottom, and giving up on imagining there is a bottom is not a serious problem-- thinking we have gotten there is the real giving up."
We are not necessarily smart enough to ever find out the 'truth'...Given what I said above, you will not be surprised I would like to reframe this as well-- into something more like "what we mean by the word 'truth' is simply whatever it is that we are smart enough, and technologically advanced enough, to figure out." That way, we do get to the truth-- but just what we mean by truth.

Brown Dwarf
2014-Sep-06, 01:25 AM
an accurate description of reality? perception