## What happens at the exact center?

How does science work? And what's all this about quantum mechanics?

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thedoc
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### Re: What happens at the exact center?

Philosophy Explorer wrote:
Mon May 21, 2018 12:43 pm
thedoc wrote:
Sun May 20, 2018 10:37 pm
Philosophy Explorer wrote:
Thu May 17, 2018 2:02 pm

Why do you say the exact center point is rotating? Movement means changing your location over time
(r x t = d). Since I contend the exact center isn't moving, then its orientation remains the same.

PhilX
The center point is changing it's orientation 360 degrees with each rotation of the record. Are you saying that changing the direction each rotation is not a movement?
As I said, the closer you get to the center of the record or spindle, the slower either one moves which you can test out for yourself doc. This means there is no movement at the center which also means the center doesn't rotate and we have a paradox since the rest of the record and spindle moves (however fast they move).

PhilX
You're right it doesn't make sense that the center point wouldn't change the direction it is facing while the rest of the turntable and record do. Is the center point totally detached from the rest of the turntable?

Philosophy Explorer
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### Re: What happens at the exact center?

thedoc wrote:
Mon May 21, 2018 2:43 pm
Philosophy Explorer wrote:
Mon May 21, 2018 12:43 pm
thedoc wrote:
Sun May 20, 2018 10:37 pm

The center point is changing it's orientation 360 degrees with each rotation of the record. Are you saying that changing the direction each rotation is not a movement?
As I said, the closer you get to the center of the record or spindle, the slower either one moves which you can test out for yourself doc. This means there is no movement at the center which also means the center doesn't rotate and we have a paradox since the rest of the record and spindle moves (however fast they move).

PhilX
You're right it doesn't make sense that the center point wouldn't change the direction it is facing while the rest of the turntable and record do. Is the center point totally detached from the rest of the turntable?
No. It's attached, otherwise there would be no paradox.

PhilX

Averroes
Posts: 319
Joined: Thu Jul 20, 2017 8:48 pm

### Re: What happens at the exact center?

Philosophy Explorer wrote:As I said, the closer you get to the center of the record or spindle, the slower either one moves which you can test out for yourself doc. This means there is no movement at the center which also means the center doesn't rotate and we have a paradox since the rest of the record and spindle moves (however fast they move).
I think that you mentioning a dimensionless point is the crucial factor here. But I think your argument can be made better! If you allow me, here is how I have come to conceive of it. You mention that the closer we get to the center of the record the slower the points of the record are moving, but that by itself does not drive your conclusion home for the audience! Let us consider a diameter on the record, ie a line passing through the center point, and let us consider motion towards the center along this line. The further we are from the center, then the faster a point is moving as it crosses this line. Let us also attach a vector to each of these points. At the extremities, we have a large vector, and the closer we get to the center, the magnitude of the velocity vector gets smaller. Now do not stop at the center, but continue pass the center, and now the vector has changed direction!! So it gets smaller as we move towards the center, and pass this center, it changes direction! So it must have stopped moving at the center! Now this is just one diameter line we have drawn on the record! Do it for all the surface area of the record, and it becomes clear that at the center point there cannot be any motion at all!
Now it is important to mention a dimensionless point, because for anything other that, i.e. r > 0, there will be motion. From a physical perspective, it does not make sense of course, but the mathematical concept is crystal clear.

Eodnhoj7
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### Re: What happens at the exact center?

thedoc wrote:
Sun May 20, 2018 4:02 am
Eodnhoj7 wrote:
Fri May 18, 2018 4:03 pm
thedoc wrote:
Fri May 18, 2018 1:30 am
Interesting philosophical discussion but unfortunately it has nothing to do with reality and practical matters.
That was not very practical for you to state that... Where the metaphysics which inevitably led to the scientific method not practical if they led to what was practical?
Scientific discoveries are made by those who look at the way the world is, not by those who imagine how they would like it to be.
Scientific discoveries are made by an "imagined" (or form which is given "image" too) paradigm: the scientific method as a imaging process of given structure to knowledge.

Show me the scientific method behind the scientific method...or is it strictly an imagined system of belief by various factions (physics,biology, etc.) of appointed priests as mediators?

What is the difference between animal sacrifice and dissection when both are used as means of knowledge and power? The steal table and the altar?

thedoc
Posts: 6473
Joined: Thu Aug 30, 2012 4:18 pm

### Re: What happens at the exact center?

Averroes wrote:
Mon May 21, 2018 4:17 pm
From a physical perspective, it does not make sense of course, but the mathematical concept is crystal clear.
I agree that as a mathematical concept it is true, but that doesn't make it true for a physical perspective. There is no such thing as a dimensionless point in the physical world, only in mathematics.

Eodnhoj7
Posts: 6051
Joined: Mon Mar 13, 2017 3:18 am

### Re: What happens at the exact center?

thedoc wrote:
Tue May 22, 2018 12:22 am
Averroes wrote:
Mon May 21, 2018 4:17 pm
From a physical perspective, it does not make sense of course, but the mathematical concept is crystal clear.
I agree that as a mathematical concept it is true, but that doesn't make it true for a physical perspective. There is no such thing as a dimensionless point in the physical world, only in mathematics.
There is no way to "test" for a point in the realm of physics as it would be composed of further points ad-finitum. A point is strictly an observation of relative spaces and where they synthesize or invert to form further spaces.

Try to find a point on a computer screen. When you find it, you will find it exists only relative to a position of observation. The problem occurs that this relation of parts, the observer is observing, is strictly dependent upon the position of observation itself. Hence the laws of physics really extend from points of observation, even the concept of gravity is merely a demarcation of a certain force relative to other forces.

Eodnhoj7
Posts: 6051
Joined: Mon Mar 13, 2017 3:18 am

### Re: What happens at the exact center?

Averroes wrote:
Mon May 21, 2018 4:17 pm
Philosophy Explorer wrote:As I said, the closer you get to the center of the record or spindle, the slower either one moves which you can test out for yourself doc. This means there is no movement at the center which also means the center doesn't rotate and we have a paradox since the rest of the record and spindle moves (however fast they move).
I think that you mentioning a dimensionless point is the crucial factor here. But I think your argument can be made better! If you allow me, here is how I have come to conceive of it. You mention that the closer we get to the center of the record the slower the points of the record are moving, but that by itself does not drive your conclusion home for the audience! Let us consider a diameter on the record, ie a line passing through the center point, and let us consider motion towards the center along this line. The further we are from the center, then the faster a point is moving as it crosses this line. Let us also attach a vector to each of these points. At the extremities, we have a large vector, and the closer we get to the center, the magnitude of the velocity vector gets smaller. Now do not stop at the center, but continue pass the center, and now the vector has changed direction!!

The point would constitute a place of "inversion" you argue where one set of dimensions inverts into another?

So it gets smaller as we move towards the center, and pass this center, it changes direction! So it must have stopped moving at the center! Now this is just one diameter line we have drawn on the record! Do it for all the surface area of the record, and it becomes clear that at the center point there cannot be any motion at all!
Now it is important to mention a dimensionless point, because for anything other that, i.e. r > 0, there will be motion. From a physical perspective, it does not make sense of course, but the mathematical concept is crystal clear.

Noax
Posts: 670
Joined: Wed Aug 10, 2016 3:25 am

### Re: What happens at the exact center?

thedoc wrote:
Mon May 21, 2018 2:43 pm
You're right it doesn't make sense that the center point wouldn't change the direction it is facing while the rest of the turntable and record do. Is the center point totally detached from the rest of the turntable?
Fear not. Symmetry is preserved.
No point has an orientation. A pair of points do. So even the points away from the spindle have no orientation in isolation, but they do move about (they accelerate in a way that points on the axis do not).

Averroes
Posts: 319
Joined: Thu Jul 20, 2017 8:48 pm

### Re: What happens at the exact center?

thedoc wrote:
Tue May 22, 2018 12:22 am
Averroes wrote:
Mon May 21, 2018 4:17 pm
From a physical perspective, it does not make sense of course, but the mathematical concept is crystal clear.
I agree that as a mathematical concept it is true, but that doesn't make it true for a physical perspective. There is no such thing as a dimensionless point in the physical world, only in mathematics.
Well, yes and no, because in a sense it can be argued! Let me explain. It is clear that the dimensionless point has no length, no width, no height, hence has no volume, has no mass etc.. so as far as the natural sciences are concerned such a thing cannot be found in space even in theory! But in mathematics we understand it very well and we accept it. And it is the very basics of mathematics. That would be the yes part of the answer.

The natural sciences purports to study the natural/physical world. So if one wanted to know about the physical world, a good place to start would be in the books on the natural sciences. But now in physics, the concept of a point particle is very widespread and is important in theories to explain phenomena! Check the entry on point particle on wikipedia.

In a nutshell, I do not think it is wise for mathematics and the natural sciences to be put in competition as to who is right or who got it better, that sort of thing. Because, firstly this is not what happens in these fields and secondly it does not further any good cause! In these fields both mathematics and the natural sciences benefit from each other, to the point that I have to come to think of mathematics as the soul of science and science as the body of mathematics. A body without a soul is known as a corpse! The soul body analogy in my opinion capture much of the relationship between science and maths.

Averroes
Posts: 319
Joined: Thu Jul 20, 2017 8:48 pm

### Re: What happens at the exact center?

Eodnhoj7 wrote:
Tue May 22, 2018 12:32 am
The point would constitute a place of "inversion" you argue where one set of dimensions inverts into another?
You could say that. In mathematics, I think there is a specific term used for that which you rightly call 'inversion'. I think it is called a point of inflection, or sometimes a minimum point or at other times a maximum point depending on the context. What is inverted here is the direction of the velocity of a point particle along the diameter we have drawn. The point is still a dimensionless entity though.

Eodnhoj7
Posts: 6051
Joined: Mon Mar 13, 2017 3:18 am

### Re: What happens at the exact center?

Averroes wrote:
Wed May 23, 2018 9:14 am
Eodnhoj7 wrote:
Tue May 22, 2018 12:32 am
The point would constitute a place of "inversion" you argue where one set of dimensions inverts into another?
You could say that. In mathematics, I think there is a specific term used for that which you rightly call 'inversion'. I think it is called a point of inflection, or sometimes a minimum point or at other times a maximum point depending on the context. What is inverted here is the direction of the velocity of a point particle along the diameter we have drawn. The point is still a dimensionless entity though.
viewtopic.php?f=26&t=23610

Averroes
Posts: 319
Joined: Thu Jul 20, 2017 8:48 pm

### Re: What happens at the exact center?

I am sorry John, but this is way too complicated for me. I cannot contribute on that post of yours at least for now because I am not familiar with the subject of your post on that thread you linked me to. May be if I get an insight into it one day, if God wills, I will contribute.

Averroes
Posts: 319
Joined: Thu Jul 20, 2017 8:48 pm

### Re: What happens at the exact center?

Averroes wrote:
Wed May 23, 2018 9:14 am
Eodnhoj7 wrote:
Tue May 22, 2018 12:32 am
The point would constitute a place of "inversion" you argue where one set of dimensions inverts into another?
You could say that. In mathematics, I think there is a specific term used for that which you rightly call 'inversion'. I think it is called a point of inflection, or sometimes a minimum point or at other times a maximum point depending on the context. What is inverted here is the direction of the velocity of a point particle along the diameter we have drawn. The point is still a dimensionless entity though.
There was a mistake here. The bolded part is mistaken. Since v and r are linearly related (i.e. v=wr), the graph is linear and hence there is no point of inflection here.

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