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Author Topic: Who understands the matrix equation Ax=b?  (Read 5535 times)

Offline Thebox

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Re: Who understands the matrix equation Ax=b?
« Reply #25 on: 17/01/2016 17:19:14 »


A hammer is a tool, and so is a nail.  Play with your tools all you like, they are fun I must admit, but if you are to use your tools to build a representation of the universe, it is necessary to refer back to reality.

The reality is that the tools haven't quite been able to fully represent the reality, so why are you blowing a trumpet over the tools?

Some tools work very well, yet some nails have no hammers. The tools are only as good as the user.
 

Offline dhjdhj

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Re: Who understands the matrix equation Ax=b?
« Reply #26 on: 17/01/2016 17:22:03 »
I think you have made your point Jeffrey
 

Offline jeffreyH

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Re: Who understands the matrix equation Ax=b?
« Reply #27 on: 17/01/2016 17:30:31 »
I think there may more of a grain of truth in Timey's post . Mathematics may have become the primary partner in the marriage with concept. Dirac took the view that structure didn't matter as long as the maths was correct. I can't reconcile myself to that view. Even the fact that Heisenberg and Schrodinger ended up with compatible maths from different concepts gives me pause for thought. From what I have read there have been notable physicists who were not good at maths. Faraday for a start. Of course if the maths is wrong, the idea cant be right ,but if the maths is right it does not necessarily mean the idea is right. I take it Jeffrey you want some one specific to solve your problem.

You are missing the point entirely. If you are fixing trucks you need particular tools. You could try just using any old thing. You could try a chainsaw to get the wheels off, or the exhaust etc etc. However it is required to use the tools of the trade. The problem with the mathematics of physics is not that it is fuzzy and bodged together but that the language used and the terms involved are understood by an exclusive set of individuals. However the same is true of the parts on a vehicle. Unusual names should not be a reason to rubbish the tools of the trade. It just means a shallow learning curve. (yes that does mean difficult unlike the misused steep learning curve.) That is no reason to avoid the learning process altogether.
 

Offline Thebox

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Re: Who understands the matrix equation Ax=b?
« Reply #28 on: 17/01/2016 17:30:41 »
I think you have made your point Jeffrey

Understanding the equation is relative to what you learnt, understanding any sort of matrix is a matter of thought, I don't think there is a point .

 

Offline Thebox

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Re: Who understands the matrix equation Ax=b?
« Reply #29 on: 17/01/2016 17:32:56 »


You are missing the point entirely. If you are fixing trucks you need particular tools. You could try just using any old thing. You could try a chainsaw to get the wheels off, or the exhaust etc etc. However it is required to use the tools of the trade. The problem with the mathematics of physics is not that it is fuzzy and bodged together but that the language used and the terms involved are understood by an exclusive set of individuals. However the same is true of the parts on a vehicle. Unusual names should not be a reason to rubbish the tools of the trade. It just means a shallow learning curve. (yes that does mean difficult unlike the misused steep learning curve.) That is no reason to avoid the learning process altogether.

It is also not wise to ignore possible new tools. Maybe your tools are old and rusty and some new tools are just better ?


An object on Earth in a inertial reference frame the Fn=0


this tool is rusty, the Fn= a  where (a) is the force of acceleration.

proof your tools can be broke.
« Last Edit: 17/01/2016 17:35:26 by Thebox »
 

Offline timey

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Re: Who understands the matrix equation Ax=b?
« Reply #30 on: 17/01/2016 18:25:23 »
Yes, mathematics 'is' a vital tool in physics, and in the understanding of physics.  But, it is not by any means the only route to understanding physics, or making a contribution to physics...  I believe it was evan-au who recently stated to me that Einstein himself had to rely on colleagues with greater mathematical skills than he to describe the concepts he'd come up with.

It sounds as if you are saying that if you do not understand the maths for general relativity then you cannot understand physics...  I've been speaking to physicists of considerable note for quite some amount of time now, and not one has been able to give me a blow by blow account of how the GR field equations are put together, usually completely ignoring me subsequently.  The most honest account of abilities I've come across is "I'm a bit rusty"... and little wonder when Leonard Susskind himself states in his GR lecture, concerning the field equations, that he's not going to give an example of the equations in use, and anyone wishing to use them should refer to a computer program!
 

Offline jeffreyH

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Re: Who understands the matrix equation Ax=b?
« Reply #31 on: 17/01/2016 19:05:50 »
The solution to the problem is

x = -13.145
y =  7.495
z = -9.205

Go here http://www.bluebit.gr/matrix-calculator/

Type the following with spaces into the matrix text area and click matrix inverse and then calculate

2    1   -4
4    5   -1
0    3    3

You should then get a new matrix with the values:

-0.750  0.625 -0.792
 0.500 -0.250  0.583
-0.500  0.250 -0.250

Copy this then click on back to online matrix calculator and then click the link matrix multiplication.

Copy the results matrix into the matrix a box then type the following into the matrix b box

3
-6
50

Then click multiply A*B. You will then get the solution for x, y and z.
 

Offline dhjdhj

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Re: Who understands the matrix equation Ax=b?
« Reply #32 on: 17/01/2016 19:13:58 »
You are missing the point entirely. If you are fixing trucks you need particular tools. You could try just using any old thing. 

I don't think I am. I absolutely agree that you need the tools and the skills to use them and maths is a tool to help understand physics, but to use your analogy if you fixing trucks the tools are determined by the job, you don't change the job to suit the tools. In my own experience as a young engineer I was required to plan the design and construction of complex projects with multiple resources and numerous uncertainties. We used many of the same mathematical tools that Physicists use, as well as creating some of our own, but the whole purpose was to get the job done our only output was progress. I don't people find the maths is so much of a barrier as the language of physics. You may have noticed I deliberately avoid this language where ever possible because it has to so precise and even physicists writing popular science books can get it wrong. My point is that maths is vital to understanding existing theories and vital to confirming new ones but surely it can not be a substitute for thought as to what is actually happening. 
 

Offline jeffreyH

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Re: Who understands the matrix equation Ax=b?
« Reply #33 on: 17/01/2016 19:21:08 »
Physics is a creative process. But you have to be able to take the idea that has been created and test it rigorously. I have nothing against creativity in physics but please don't expect others to finish off the job. If you can't take your own idea further then that is your problem. Why should anyone give up their time and take it away from time with family or friends on a whim? Criticism is one thing but investment of time is another.
 

Offline Thebox

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Re: Who understands the matrix equation Ax=b?
« Reply #34 on: 17/01/2016 19:39:59 »
Physics is a creative process. But you have to be able to take the idea that has been created and test it rigorously. I have nothing against creativity in physics but please don't expect others to finish off the job. If you can't take your own idea further then that is your problem. Why should anyone give up their time and take it away from time with family or friends on a whim? Criticism is one thing but investment of time is another.

The problem I see is that science thinks every idea needs maths and that every idea can be explained in extent. You say why should anyone give their time to help an idea which the goal  is to get it publicised and recognised .  I ask why should we give our time and even contribute to a science forum if the only aim of science is to snub us and not help us?
It saves time if we work together with ideas.   Maxwell helped Faraday yet modern day is selfish, the sort of question you ask is a selfish question, why should you give the time really means , what is in it for us.

We clearly can see that some ideas are just plain stupid, but we can also see the ideas that do have premise for argument.  These ideas with the help of a science type and the crackpot could develop into something that little bit special.



 

Offline Thebox

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Re: Who understands the matrix equation Ax=b?
« Reply #35 on: 17/01/2016 19:49:56 »
The solution to the problem is

x = -13.145
y =  7.495
z = -9.205

Go here http://www.bluebit.gr/matrix-calculator/

Type the following with spaces into the matrix text area and click matrix inverse and then calculate

2    1   -4
4    5   -1
0    3    3

You should then get a new matrix with the values:

-0.750  0.625 -0.792
 0.500 -0.250  0.583
-0.500  0.250 -0.250

Copy this then click on back to online matrix calculator and then click the link matrix multiplication.

Copy the results matrix into the matrix a box then type the following into the matrix b box

3
-6
50

Then click multiply A*B. You will then get the solution for x, y and z.

Using a calculator is cheating and I still have no idea of what it is trying to show or represent?
 

Offline timey

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Re: Who understands the matrix equation Ax=b?
« Reply #36 on: 17/01/2016 19:59:29 »
Physics is a creative process. But you have to be able to take the idea that has been created and test it rigorously. I have nothing against creativity in physics but please don't expect others to finish off the job. If you can't take your own idea further then that is your problem. Why should anyone give up their time and take it away from time with family or friends on a whim? Criticism is one thing but investment of time is another.

You are aware that there are massive prizes for break through's in all areas of science and mathematics?  The break through prize alone is 3 mill, this being each for physics, maths and other areas in science.  Depends how interesting you think another's ideas are I'd expect...
 

Offline jeffreyH

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Re: Who understands the matrix equation Ax=b?
« Reply #37 on: 17/01/2016 20:01:22 »
I could go through it step by step but I won't. Google row echelon form and do a bit of reading. You might actually learn something.
 

Offline timey

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Re: Who understands the matrix equation Ax=b?
« Reply #38 on: 17/01/2016 20:16:46 »
Why would I look up and learn how to manipulate a series of mathematics that I have had explained to me by Leonard Suskind via his lectures, that I recall reading that you have watched, or are watching yourself, and that I have come to the conclusion are faulty, as did their creator Einstien.

Defies logic really.

Furthermore, I'll bet that you cannot in fact give me an example of the GR field equations in use without recourse to a maths program, or another persons work.
 

Offline Thebox

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Re: Who understands the matrix equation Ax=b?
« Reply #39 on: 17/01/2016 20:24:24 »
I could go through it step by step but I won't. Google row echelon form and do a bit of reading. You might actually learn something.

I looked it up and I am still no wiser to what it suppose to represent apart from grid reference frames.


000
000
000

we could cube that giving a cube of zero value, i.e ''empty space''


Is what you are on about something to do with computer programming?  otherwise I am at a loss to the relevance of this.

 

Offline dhjdhj

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Re: Who understands the matrix equation Ax=b?
« Reply #40 on: 17/01/2016 20:28:26 »
Jeffrey I think you are referring to my idea/hypothesis/hunch and you are right I am a bit stuck, and I would like some help, but only IF the idea is worth pursuing. Now unlike timey I have no paranoia, I am a retiree with a good life style. I don't need any fame or fortune. What I do need is someone to tell me what's wrong so I can either work round it or move on. Now if you are saying that what I have proposed contains no obvious violations of basic physics, but needs mathematical validation either positive or negative then that's a whole new ball game. Mathematicians I can find. Physicists are like hen's teeth, good ones even rarer.
 

Offline Thebox

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Re: Who understands the matrix equation Ax=b?
« Reply #41 on: 17/01/2016 20:39:24 »
Jeffrey I think you are referring to my idea/hypothesis/hunch and you are right I am a bit stuck, and I would like some help, but only IF the idea is worth pursuing. Now unlike timey I have no paranoia, I am a retiree with a good life style. I don't need any fame or fortune. What I do need is someone to tell me what's wrong so I can either work round it or move on. Now if you are saying that what I have proposed contains no obvious violations of basic physics, but needs mathematical validation either positive or negative then that's a whole new ball game. Mathematicians I can find. Physicists are like hen's teeth, good ones even rarer.

which idea dh? 

this one

''concept of time is that time makes things exist.''


time does not exist,
 

Offline dhjdhj

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Re: Who understands the matrix equation Ax=b?
« Reply #42 on: 17/01/2016 20:45:11 »
Well then there you go. Julian Barbour agrees with you, but not many others
 

Offline Thebox

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Re: Who understands the matrix equation Ax=b?
« Reply #43 on: 17/01/2016 20:48:03 »
Well then there you go. Julian Barbour agrees with you, but not many others

I do not care about Julian Barbour , I do not care about prizes, I care that science gets it right, I  have proved time does not exist , do you not read other threads?


 

Offline timey

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Re: Who understands the matrix equation Ax=b?
« Reply #44 on: 17/01/2016 20:51:26 »
Jeffrey I think you are referring to my idea/hypothesis/hunch and you are right I am a bit stuck, and I would like some help, but only IF the idea is worth pursuing. Now unlike timey I have no paranoia, I am a retiree with a good life style. I don't need any fame or fortune. What I do need is someone to tell me what's wrong so I can either work round it or move on. Now if you are saying that what I have proposed contains no obvious violations of basic physics, but needs mathematical validation either positive or negative then that's a whole new ball game. Mathematicians I can find. Physicists are like hen's teeth, good ones even rarer.

Why would you say I am paranoid?  Jeff and I have a history, I think you may be missing the subtleties.  Jeff btw is a self professed non physicist who 'is' pretty nifty with the maths, at least.
 

Offline dhjdhj

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Re: Who understands the matrix equation Ax=b?
« Reply #45 on: 17/01/2016 21:12:23 »
It was your reference to money and people stealing ideas. If I got the wrong end of the stick I apologise.
 

Offline jeffreyH

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Re: Who understands the matrix equation Ax=b?
« Reply #46 on: 17/01/2016 21:42:57 »
Jeffrey I think you are referring to my idea/hypothesis/hunch and you are right I am a bit stuck, and I would like some help, but only IF the idea is worth pursuing. Now unlike timey I have no paranoia, I am a retiree with a good life style. I don't need any fame or fortune. What I do need is someone to tell me what's wrong so I can either work round it or move on. Now if you are saying that what I have proposed contains no obvious violations of basic physics, but needs mathematical validation either positive or negative then that's a whole new ball game. Mathematicians I can find. Physicists are like hen's teeth, good ones even rarer.

How much particle physics have you learned? Also do you know quantum mechanics?
 

Offline jeffreyH

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Re: Who understands the matrix equation Ax=b?
« Reply #47 on: 17/01/2016 21:55:03 »
The solution to the problem is

x = -13.145
y =  7.495
z = -9.205

Go here http://www.bluebit.gr/matrix-calculator/

Type the following with spaces into the matrix text area and click matrix inverse and then calculate

2    1   -4
4    5   -1
0    3    3

You should then get a new matrix with the values:

-0.750  0.625 -0.792
 0.500 -0.250  0.583
-0.500  0.250 -0.250

Copy this then click on back to online matrix calculator and then click the link matrix multiplication.

Copy the results matrix into the matrix a box then type the following into the matrix b box

3
-6
50

Then click multiply A*B. You will then get the solution for x, y and z.

Using a calculator is cheating and I still have no idea of what it is trying to show or represent?

We started out with 3 equations

2x + y - 4z = 3
4x + 5y - z = -6
       3y - 3z = 50

The solution is the values for x, y and z that solved ALL 3 equations.

Using the calculator was a way to show, via an online tool, what the correct answer was.

The answer came out as:

x = -13.145
y =  7.495
z = -9.205

So the equations now become

2 * -13.145 + 7.495 - 4 * -9.205 = 3
4 * -13.145 + 5 * 7.495 - -9.205 = -6
       3 * 7.495 - 3 * -9.205 = 50

I don't know how much more straightforward I can make it.
 

Offline dhjdhj

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Re: Who understands the matrix equation Ax=b?
« Reply #48 on: 17/01/2016 21:58:34 »
The answer to both questions is enough to get into trouble but not enough to get out. I certainly understand the basic posits and incidentally most of the disagreements. That's why I need a physicist.
 

Offline timey

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Re: Who understands the matrix equation Ax=b?
« Reply #49 on: 17/01/2016 22:01:24 »
It was your reference to money and people stealing ideas. If I got the wrong end of the stick I apologise.

Ah, I see.  Yes, wrong end of stick.  Jeff was asking why a mathematician would bother to take time out from family and life to equate another's ideas.  I was saying because the prize money for both maths and physics is a worthy cause, and it would depend on how interesting the mathematician thought the other persons ideas are, as to wether doing so could be considered worthwhile.
 

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Re: Who understands the matrix equation Ax=b?
« Reply #49 on: 17/01/2016 22:01:24 »

 

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