What does physics describe?

  • Thread starter RuroumiKenshin
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  • #36


Originally posted by Alexander
Excuse me? How can you DESCRIBE what have not happened yet?

probability helps.
 
  • #37
See - you use math (probabbilities).

(And if you use math correctly and did not forget to include anything important, then you get corresponding to reality result).
 
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  • #38
Mentat
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Originally posted by Alexander
Excuse me? How can you DESCRIBE what have not happened yet?

By making predictions. I formulate a theory, that is capable of making predictions, then I should be able to describe how phenomena will be, if my theory holds true.
 
  • #39
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Originally posted by Alexander
No. What is PHYSICAL here? Nothing. Just math: take an equation of a wave and place a constrains 1/r on it.

But the equation of the wave just describes the actual physical phenomenon. Don't you believe in an objective reality at all? If you do, then you cannot believe that something that can only be understood within the minds of sentient beings (like mathematics), and is therefore subjective, can have any control over physical phenomena.
 
  • #40
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Originally posted by Alexander
No, math does NOT say so. You do. You are NOT math.



Numbers are NOT language.

Says who? The things that the numbers are describing are not language, but the numbers themselves are.

Think of this (to help illustrate the subjective nature of numbers): If I say "6", I have not described anything. I could just as easily be talking about an amount as a degree. I could just as easily be describing someone's age, as someone's height. I could just as easily be describing the result of a certain mathematical equation as another mathematical equation (such as 3+3 and 12/2). It is purely subjective, and useless, unless some actual attribute is assigned to it.
 
  • #41
heusdens
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Originally posted by MajinVegeta
"Everything is a result of physics".

That two atoms of Hydrogen and one atom of Oxygen can form a molecule of water, ain't physics, but is chemistry. Even if the property of the atoms involved, can be derived from physcial properties of the atoms.

"Everything is a result of physcics" therefore is a notion of reality, which can be called "physicalism".

In reality we deal with other levels of describing reality.

It would be pretty absurd to explain the economic crisis in terms of physical behaviour of matter. Economy is better to describe this level of reality.

etc.
 
  • #42
Originally posted by Mentat
Says who?


Logic.

Think of this (to help illustrate the subjective nature of numbers): If I say "6", I have not described anything. I could just as easily be talking about an amount as a degree. I could just as easily be describing someone's age, as someone's height. I could just as easily be describing the result of a certain mathematical equation as another mathematical equation (such as 3+3 and 12/2).

It is purely subjective, and useless, unless some actual attribute is assigned to it.
You have just proven the contary - that a math (in your case the number 6) is objective (=independent from human or alien existence), and that a math abstract concept (= not directly related to concrete objects). In you example 6 is still 6 in ALL of you cases, but the objects you tried to tie it to are VERY different and have nothing in common by themselves.
 
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  • #43


Originally posted by heusdens
That two atoms of Hydrogen and one atom of Oxygen can form a molecule of water, ain't physics, but is chemistry.


Chemistry is just quantum mechanics of electromagnetic interaction of bunches of electrons and protons.

"Everything is a result of physcics" therefore is a notion of reality, which can be called "physicalism".
Everything is indeed the result of physics, physics is the result of math, math is the result of logic, logic is the result of existence.

So everything is just a result of existence.

It would be pretty absurd to explain the economic crisis in terms of physical behaviour of matter. Economy is better to describe this level of reality.

etc.

No, it would not. Just too complex (bulky) to derive from the first principles, so as always in such situations - the statistical approach (called economics) is quickier and far less labor consuming, (although not very accurate).
 
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  • #44
Originally posted by Mentat
But the equation of the wave just describes the actual physical phenomenon.


No, equation of wave does not. It (equation) is just a trigonometric identity.

Don't you believe in an objective reality at all?
Yes. Objective reality is what math allows to do to mathematical objects (like a rainbow, a crystal, an atom, an eclipse, a star, a planet, a planet orbit, etc).

If you do, then you cannot believe that something that can only be understood within the minds of sentient beings (like mathematics), and is therefore subjective, can have any control over physical phenomena.

This is exactly where you error (or misunderstanding) lies - that math is a subjective invention of homo sapience during last couple millenia here on Earth. It is not. It (math) is just a logic of existence, so it is same for all existing objects. Pithagorean threorem sin2+cos2=1 was valid before Pithagorah too.

All civilisations on Earth have the SAME math regardless notations they use (and notations are constantly changing).

Math is just a logic of existence itself.
 
  • #45
ahrkron
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Originally posted by Alexander
Math is just a logic of existence itself.

Almost right.

Logic is also tied to the behavior we call "thinking". This introduces a lot more to talk about.

Regarding to your idea of "existence itself", all we can do is describe the result of what we call "experiments", but also, and more important, your very post is making a clear distiction between "existence itself" and its "logic".

So, yes, Math is the logic (=the structure of thoughts) we have developed from our interaction with "existence itself".

i.e., you also needed to refer to "existence itself" and its structure. Math is the representation of the structure of physical interactions. It has no independent existence, much in te way you cannot claim the height, width and length of a cube to give it existence. You can have the full set of equations and boundary conditions for all particles and waves that build a house, and yet there is no house.

Equations by themselves create nothing.
"Math" is structure,... yes, but in order to talk about reality, you always need to ask "structure of what?".
 
  • #46


Originally posted by Mentat
By making predictions. I formulate a theory, that is capable of making predictions, then I should be able to describe how phenomena will be, if my theory holds true.

Stop right here! Description can not "formulate a theory" not to say of one "capable of making prediction". It takes at least logic (and usually in advanced form we call math) to formulate a theory. Not a description anymore.

So, you can not DESCRIBE what WILL happen. By definition of description. There is NOTHING to DESCRIBE yet.

(Imagine a policeman taking witness testimony: "Describe what WILL happen").
 
  • #47
Originally posted by ahrkron


You can have the full set of equations and boundary conditions for all particles and waves that build a house, and yet there is no house.


Actually you don't (have all equations). If you were, there obviousely was a house.
 
  • #48
ahrkron
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Originally posted by Alexander
Actually you don't (have all equations). If you were, there obviousely was a house.

I wonder how you can honestly believe that.

What about the following:

Let S(u) denote the points that satisfy x2+y2+z2=1 cm2

Where:
u is any PF's member
x is measured along the x-axis of u's monitor
y along the y axis
z is the direction from the center of the screen to the point between u's eyes.

And (0,0,0) is the middle point of the line that joins u's eyes and the center of u's monitor.

Then, the set of equations

Z = Union of all points that satisfy S(u) for all u's logged on right now,

Is the set of perfect spheres, each 1 cm radius, floating in between all users of PF logged on right now and their monitors.

I have the equations... and see no sphere.

Does anybody see his or her sphere?
 
  • #49
Hurkyl
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Maybe if I squint really hard...
 
  • #50
Originally posted by ahrkron
I wonder how you can honestly believe that.


I don't believe anything (accept on faith).This simply follows from logic.
What about the following:...

...Is the set of perfect spheres, each 1 cm radius, floating in between all users of PF logged on right now and their monitors.

I have the equations... and see no sphere.

Does anybody see his or her sphere?

This is dumb, because your sphere does not make photons yet. How can you "see" without any light?

To SEE something, your eye shall absorb 2-3 eV photons (this is DEFINITION of seeing).

(I told you already that you have to have equations which you don't).
 
  • #51
Originally posted by Hurkyl
Maybe if I squint really hard...

What you see is just your imagination. There is no light in the system yet.
 
  • #52
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Originally posted by Alexander
Logic.

Logic says that numbers are not language?

You have just proven the contary - that a math (in your case the number 6) is objective (=independent from human or alien existence), and that a math abstract concept (= not directly related to concrete objects). In you example 6 is still 6 in ALL of you cases, but the objects you tried to tie it to are VERY different and have nothing in common by themselves.

Exactly, 6 is not a solid concept, because it can be used for many (entirely unrelated) things.
 
  • #53
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Originally posted by Alexander
No, equation of wave does not. It (equation) is just a trigonometric identity.

Yes, that's all that it is. Nothing more. And of what use is it, if you can't use it to describe anything that really exists? LogicalAtheists brougth up the equation 100=99. This is an equation, and is thus mathematical. It is not logical, but it still exists within the realm of the language of mathematics. It has no use, because it cannot describe any real physical phenomena.

Yes. Objective reality is what math allows to do to mathematical objects (like a rainbow, a crystal, an atom, an eclipse, a star, a planet, a planet orbit, etc).

You're preaching again. You haven't substantiated anything you've said.

Your reasoning is exactly the same as those who, when asked what proof there is of a Creator, say "just look at all of the creation".

All civilisations on Earth have the SAME math regardless notations they use (and notations are constantly changing).

So what?
 
  • #54
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Originally posted by Alexander
I don't believe anything (accept on faith).This simply follows from logic.

You've just contradicted yourself. You said you didn't believe in anything, and then you used logic as a final source, taking for granted that it must be right, because it's logical.

This is dumb, because your sphere does not make photons yet. How can you "see" without any light?

Yes, even if the equations for seeing with light existed - if there is no (physical) light, there is no vision.
 
  • #55
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Originally posted by Alexander
Actually you don't (have all equations). If you were, there obviousely was a house.

Why's that? If I have all of the equations that govern the construction of a house, that doesn't mean that there was a house. It means that I have all of the equations that govern the construction of a house. You make it appear as though one could pull money out of thin air, merely by "telling" the atoms what they are mathematically "supposed" to do.
 
  • #56
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Originally posted by Alexander
Stop right here! Description can not "formulate a theory" not to say of one "capable of making prediction". It takes at least logic (and usually in advanced form we call math) to formulate a theory.

Yes, it takes logic to formulate a theory, but a theory is a description of some phenomenon.

So, you can not DESCRIBE what WILL happen. By definition of description. There is NOTHING to DESCRIBE yet.

Yes, and there is nothing to predict yet, but there will be. A prediction doesn't describe what exists now, does it?

(Imagine a policeman taking witness testimony: "Describe what WILL happen").

That policeman would be asking the witness to make an accurate prediction.
 
  • #57
Originally posted by Mentat
Why's that? If I have all of the equations that govern the construction of a house, that doesn't mean that there was a house.

It does. If you have them.

If you don't have a house yet, then obviousely you don't have all equations yet.
 
  • #58


Originally posted by Mentat

Yes, and there is nothing to predict yet, but there will be. A prediction doesn't describe what exists now, does it?



Beg you to differ a description from a prediction. Different animals.
 
  • #59
Mentat
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Originally posted by Alexander
It does. If you have them.

If you don't have a house yet, then obviousely you don't have all equations yet.

Originally posted by Me
You make it appear as though one could pull money out of thin air, merely by "telling" the atoms what they are mathematically "supposed" to do.
 
  • #60
Originally posted by Mentat

LogicalAtheists brougth up the equation 100=99. This is an equation, and is thus mathematical.


Incorrect. This is NOT an equation. To qualify for an equation it shall have EQUAL sides - which it does not have. So, this is not an equation. Sorry for correction.
 
  • #61
Mentat
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Originally posted by Alexander
Beg you to differ a description from a prediction. Different animals.

Yes they are different. A description can be about the past (=History), the present, or the future. Only when it is about the future is it a prediction.
 
  • #62
Originally posted by Mentat


You're preaching again. You haven't substantiated anything you've said.

I can. But it also takes understanding of the subject of discussion on your side.

Do you understand optics, for instance? Then I can explain you creation of such simple object as a rainbow, for example.
 
  • #63
Mentat
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Originally posted by Alexander
I can. But it also takes understanding of the subject of discussion on your side.

Do you understand optics, for instance? Then I can explain you creation of such simple object as a rainbow, for example.

You must be really used to saying the same thing many times over, and it's blinding you from what I'm saying: You...Are...Preaching...Your...Own...Belief...But...It's...Not...Necessarily...True. In...fact...the...Hurdles...to...your...belief...make...it...very...unlikely.
 
  • #64
Originally posted by Mentat
You must be really used to saying the same thing many times over, and it's blinding you from what I'm saying: You...Are...Preaching...Your...Own...Belief...But...It's...Not...Necessarily...True. In...fact...the...Hurdles...to...your...belief...make...it...very...unlikely.

Anything to say about the subject (origin of rainbow)? If not, I can safely assume that you don't know it (or don't understand it).
 
  • #65


Originally posted by Mentat
Yes they are different. A description can be about the past (=History), the present, or the future. Only when it is about the future is it a prediction.

Good, we making progress (although slow, but it is ok, I am quite patient).

So, past and present can be described, but future can not. Simply because there is nothing to describe yet.

That is why math is NOT a mere description. It goes one step beyond - it predicts.

That is why engineers use math instead of just plain english to predict how much load can a bridge stand.

That is why math is so successful - without having the actual bridge it can accurately predict if the FUTURE bridge will hold certain load, or it needs to be reidesigned or reinforced.

No language can do that (predict capacity).

See the predictive power of math?

That is why math is DIFFERENT (that a language). Don't mix them anymore, ok?
 
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  • #66
Mentat
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Originally posted by Alexander
Anything to say about the subject (origin of rainbow)? If not, I can safely assume that you don't know it (or don't understand it).

I didn't respond about the rainbow, because you have already "explained" it's origin (as it is held in your religion) and I don't think I'll get anywhere by telling you that you are using mathematics to desribe a physical phenomenon (as I've already told you this, but you ignored me).
 
  • #67
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Originally posted by Alexander
Good, we making progress (although slow, but it is ok, I am quite patient).

That's commendable.

So, past and present can be described, but future can not. Simply because there is nothing to describe yet.

Not exactly. The future can be described, it's called a prediction. But, if science is wrong (and I'm not saying it is), then the Universe may be perfectly random, and thus unpredictable.

That is why math is NOT a mere description. It goes one step beyond - it predicts.

It describes the future.

That is why engineers use math instead of just plain english to predict how much load can a bridge stand.

That is why math is so successful - without having the actual bridge it can accurately predict if the FUTURE bridge will hold certain load, or it needs to be reidesigned or reinforced.

No language can do that (predict capacity).

See the predictive power of math?

Yes, I see the predictive power of math. I've always known it. However, if science is wrong (and I'm not saying it is, I'm just being open-minded), then mathematics doesn't actually have any "predictive power", and it is only chance that has allowed it to be "right" so many times.

Also (and this is important), if something is a tool of description (whether it be description of the present, past, or the future (prediction)), it is not causing anything, but merely describing it.

That is why math is DIFFERENT (that a language). Don't mix them anymore, ok?

No, not ok. We have your opinion, and that's all it is. Remember, typical language, logical (deductive) reasoning, can predict things also, without the use of mathematics. They are not, necessarily, as different as you think.
 
  • #68
drag
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Language can predict, sure it can. :wink:
I mean if there's a large fresh hot pizza in front
of me and I'm hungry, well, it's not that difficult
to predict what will happen...
Of course, I can't quantify the chances of this
most likely outcome - whatever it may be, but you can
bet they're pretty high...
 
  • #69
Mentat
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Waiting for Alexander's response (and trying to keep this thread on the first page :wink:)...
 
  • #70


Originally posted by Mentat
Blah blah blah...
Remember, typical language, logical (deductive) reasoning, can predict things also, without the use of mathematics. They are not, necessarily, as different as you think. [/B]

To show you on a simple undertandable to you example how wrong are your long posts just try to predict what might be the result of tripling of a few coins you have in your pocket. Plain english is fine to make a valuable prediction. Feel free NOT to use any math (say, numbers).
 

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