Understanding electromagnetism

Post Reply
Farsight
Posts: 437
Joined: Mon Mar 08, 2010 10:52 am
Contact:

Re: Understanding electromagnetism

Post by Farsight » Sun May 30, 2010 12:06 pm

lpetrich wrote:
Farsight wrote:
Twiglet wrote:It could hardly be simpler. E=mc^2=m0c^2/(1-v^2/c^2)^1/2 In the limit as v approaches c, E approaches infinity, hence infinite energy is required to propel any particle with inertial mass to the speed of light.
This is woefully inadequate. It's like saying "because the runes tell me". A mathematical expression doesn't explain why c is the limit. And it doesn't explain why the particle has inertial mass or why E approaches infinity.
Farsight, why do you think that mathematics incapable of giving the reason? What would you consider acceptable reasoning and why?
Because you can't use mathematics to define the terms you use in that mathematics. You have to refer to reality, and the nature of the real world is why c is the limit, not the mathematics.
lpetrich wrote:The mathematics is an important part of the theory, so it is completely legitimate to mention it.
Of course it is. But it's a mistake to think that c is the limit because of the mathematics.
lpetrich wrote:
Now come on, you set the challenge, I've risen to it by explaining E and m in these two threads:

http://www.rationalia.com/forum/viewtop ... =9&t=12530
http://www.rationalia.com/forum/viewtop ... =9&t=12575

..so let's have your response.
Lots and lots of words and some pretty pictures, but no real consideration of the appropriate mathematical formulations.
They are considerations of the mathemtical terms E and m.
lpetrich wrote:
Your smokescreen of irrelevant off-topic mathematics doesn't cover your evasion. Particularly since it was you who challenged me to explain pair production, which is why I started this thread. ...
The mathematics is completely on-topic. Why do you think it isn't?
Because this is the "Understanding Electromagnetism" thread, and Twiglet is talking about why c is the limit, and then proposed a ballistics exercise. It's just one deliberate dereail after another.

Farsight
Posts: 437
Joined: Mon Mar 08, 2010 10:52 am
Contact:

Re: Understanding electromagnetism

Post by Farsight » Sun May 30, 2010 12:09 pm

Tigger wrote:
Farsight wrote:
Twiglet wrote:It could hardly be simpler. E=mc^2=m0c^2/(1-v^2/c^2)^1/2 In the limit as v approaches c, E approaches infinity, hence infinite energy is required to propel any particle with inertial mass to the speed of light.
This is woefully inadequate. It's like saying "because the runes tell me". A mathematical expression doesn't explain why c is the limit.
Aha! I see it all now. Having actually derived this mathematical expression from first principles when I was in my final year maths degree course studying a "basic" QM module, and with a PM from Twiglet and a post by Colubridae (cheers) to remind me of the derivation, I see the problem in this thread - and others. Farsight, this expression is indeed sufficient (to use the mathematical meaning) to demonstrate that c is the limit. If you accept the mathematical axioms literally starting before 1+1=2, and follow them through, the above equation is inarguable and by definition it does explain.
No it doesn't. If you want to prove me wrong, start a thread starting from 1+1=2 and end up explaining why c is the limit. You won't be able to.

Farsight
Posts: 437
Joined: Mon Mar 08, 2010 10:52 am
Contact:

Re: Understanding electromagnetism

Post by Farsight » Sun May 30, 2010 2:06 pm

OK Twiglet, I've explained energy and mass, and now I've explained why c is the limit. See http://www.rationalia.com/forum/viewtop ... =9&t=12686. It's all very simple and it's backed up by the scientific evidence. It ought to tell you why the various equations of SR apply, with no requirement for any assumptions or laws. And it should fit very tidily with that conceptual model you were talking about. Light or energy/momentum or action moves at c. Matter is action trapped in a circular path, and for matter to go as fast as light, that action has to be moving linearly at c and still describing a circular path. That means the action would have to be going at more than c, but it can't, because light doesn't travel faster than light.

User avatar
Twiglet
Posts: 371
Joined: Fri Apr 09, 2010 1:33 pm
Location: Australia
Contact:

Re: Understanding electromagnetism

Post by Twiglet » Sun May 30, 2010 2:13 pm

Farsight wrote:OK Twiglet, I've explained energy and mass, and now I've explained why c is the limit. See http://www.rationalia.com/forum/viewtop ... =9&t=12686. It's all very simple and it's backed up by the scientific evidence. It ought to tell you why the various equations of SR apply, with no requirement for any assumptions or laws. And it should fit very tidily with that conceptual model you were talking about. Light or energy/momentum or action moves at c. Matter is action trapped in a circular path, and for matter to go as fast as light, that action has to be moving linearly at c and still describing a circular path. That means the action would have to be going at more than c, but it can't, because light doesn't travel faster than light.
Yet you are unable to solve basic mechanics problems, or understand the implications of simple problems in special relativity. Come back to me when you can.

Farsight
Posts: 437
Joined: Mon Mar 08, 2010 10:52 am
Contact:

Re: Understanding electromagnetism

Post by Farsight » Sun May 30, 2010 2:55 pm

Twiglet wrote:Yet you are unable to solve basic mechanics problems, or understand the implications of simple problems in special relativity. Come back to me when you can.
Shrug. I've given solutions to some of your little maths tests on mistermack's thread. I've risen to your c is the limit challenge, and now you're doing a runner and being dishonest to boot. Suit yourself. But don't think people won't notice.

User avatar
Twiglet
Posts: 371
Joined: Fri Apr 09, 2010 1:33 pm
Location: Australia
Contact:

Re: Understanding electromagnetism

Post by Twiglet » Sun May 30, 2010 3:02 pm

Farsight wrote:
Twiglet wrote:Yet you are unable to solve basic mechanics problems, or understand the implications of simple problems in special relativity. Come back to me when you can.
Shrug. I've given solutions to some of your little maths tests on mistermack's thread. I've risen to your c is the limit challenge, and now you're doing a runner and being dishonest to boot. Suit yourself. But don't think people won't notice.
Heh... looking up a formula and plugging numbers into it you mean? Sure, you obtained a correct numerical result. Well done etc. A shame the conceptual meaning of that result is still beyond you.

You didn't solve any of the mechanics problems, or even attempt to do so. You didn't understand the result of the relativity problem you numerically solved plugging in numbers from a printed formula you don't conceptually understand.

As for honesty, thats easily judged farsight, because I confined my discussion to a level where you utter failures are glaringly obvious to the audience following these threads. They aren't PhD stuff, they are A level stuff. And you are stuffing it up. No amount of linguistic argument is going to win popular support for you. The genie is out of the bottle.
Last edited by Twiglet on Mon May 31, 2010 12:17 am, edited 1 time in total.

lpetrich
Posts: 303
Joined: Wed Feb 24, 2010 8:59 pm
Contact:

Re: Understanding electromagnetism

Post by lpetrich » Sun May 30, 2010 4:18 pm

Farsight wrote:
lpetrich wrote:Farsight, why do you think that mathematics incapable of giving the reason? What would you consider acceptable reasoning and why?
Because you can't use mathematics to define the terms you use in that mathematics. You have to refer to reality, and the nature of the real world is why c is the limit, not the mathematics.
Farsight, your arguments are based on language, and one can interpret mathematics as a kind of language.

Why don't you read that Wikibooks introduction to special relativity?

SR is based on these premises:

* The laws of nature look the same after linear transformations of space and time, with appropriate transformations of other quantities to match. Newtonian mechanics satisfies this condition, though SR differs from Newtonianism in permitting time to get input from space like space getting input from time.

* The speed of light in a vacuum, c, is a cosmic constant. Anything observed to travel at c will always be observed to travel at c in any coordinate system.

From these two premises, one deduces the form a Lorentz boost.

Newton -- Galilean boost:
t' = t
x' = x - v*t
Einstein -- Lorentz boost:
t' = g*(t - v*x/c2)
x' = g*(x - v*t)
g = (1 - v2/c2)-1/2

I can quote chapter and verse from Einstein himself on this subject. Farsight, you really have to recognize that your proof-texting Einstein's writings makes you look like a creationist.

Turning to momentum, one imposes conservation of it and applies a Lorentz boost to a glancing collision. One finds relativistic momentum from this:

p = g*m0*v

m0 = rest mass

Energy one gets from the work equation dE = (dp/dt).dx = v.dp It is:

E = g*m0*c2

Using the relativistic mass m = g*m0 we get:

p = m*v
E = m*c2

Yes, Einstein's famous equation.
lpetrich wrote:The mathematics is an important part of the theory, so it is completely legitimate to mention it.
Of course it is. But it's a mistake to think that c is the limit because of the mathematics.
I use mathematics to derive my results, the way that you use hand-waving linguistic descriptions. Your disdain for mathematics is a throwback to Aristotelian physics.

Farsight wrote:
lpetrich wrote:The mathematics is completely on-topic. Why do you think it isn't?
Because this is the "Understanding Electromagnetism" thread, and Twiglet is talking about why c is the limit, and then proposed a ballistics exercise. It's just one deliberate dereail after another.
No, it's a VERY simple exercise in putting mathematics to work. Farsight, your main response so far has been " :cry: Why do I need mathematics?"
Farsight wrote:OK Twiglet, I've explained energy and mass, and now I've explained why c is the limit. See http://www.rationalia.com/forum/viewtop ... =9&t=12686. It's all very simple and it's backed up by the scientific evidence. It ought to tell you why the various equations of SR apply, with no requirement for any assumptions or laws. And it should fit very tidily with that conceptual model you were talking about.
Can you work out the numbers? Like how momentum and energy increase with velocity.
Light or energy/momentum or action moves at c. Matter is action trapped in a circular path, and for matter to go as fast as light, that action has to be moving linearly at c and still describing a circular path. That means the action would have to be going at more than c, but it can't, because light doesn't travel faster than light.
What makes the light go in circles? How do you get relativistic momentum and energy from that?

Farsight
Posts: 437
Joined: Mon Mar 08, 2010 10:52 am
Contact:

Re: Understanding electromagnetism

Post by Farsight » Mon May 31, 2010 3:20 pm

lpetrich wrote:
Farsight wrote:
lpetrich wrote:Farsight, why do you think that mathematics incapable of giving the reason? What would you consider acceptable reasoning and why?
Because you can't use mathematics to define the terms you use in that mathematics. You have to refer to reality, and the nature of the real world is why c is the limit, not the mathematics.
Farsight, your arguments are based on language, and one can interpret mathematics as a kind of language.
Yes, of course. And to really understand that language, one has to know what the words mean. Thus one has to understand terms such as E, m, c, etc.
lpetrich wrote:[Why don't you read that Wikibooks introduction to special relativity?
Because I'm way past that level.
lpetrich wrote:SR is based on these premises:

* The laws of nature look the same after linear transformations of space and time, with appropriate transformations of other quantities to match. Newtonian mechanics satisfies this condition, though SR differs from Newtonianism in permitting time to get input from space like space getting input from time.

* The speed of light in a vacuum, c, is a cosmic constant. Anything observed to travel at c will always be observed to travel at c in any coordinate system.
There are no "laws of nature". There are symmetries, and time is an emergent property of motion. And the speed of light is not constant. Einstein said so, and the scientific evidence says so.
lpetrich wrote:From these two premises, one deduces the form a Lorentz boost...
The premises are inadequate. You know yourself about symmetry underlying "the laws of nature", and Einstein said the second premise was inadequate in 1916.
lpetrich wrote:I can quote chapter and verse from Einstein himself on this subject. Farsight, you really have to recognize that your proof-texting Einstein's writings makes you look like a creationist.
Quote away. I'm not the one who looks like a creationist. I've given the Einstein quotes, and the scientific evidence, and I'm the one explaining the mathematical terms and the underlying reality. You're the one avoiding it.
lpetrich wrote:I use mathematics to derive my results, the way that you use hand-waving linguistic descriptions. Your disdain for mathematics is a throwback to Aristotelian physics.
I have no disdain for mathematics. I merely recognise that whilst it's a vital tool for physics, it isn't the only tool. Your disdain for experimental evidence is a throwback to crystal spheres.
lpetrich wrote:No, it's a VERY simple exercise in putting mathematics to work. Farsight, your main response so far has been ":cry: Why do I need mathematics?"
No, I've taken pains to explain the mathemtical terms and give the references and describe the experiments. Your response has been ":cry: Why do I need to bother with all that when I've got the mathematics?"
Ipetrich wrote:Can you work out the numbers? Like how momentum and energy increase with velocity.
Of course I can. Ask me on the appropriate thread.
Ipetrich wrote:What makes the light go in circles? How do you get relativistic momentum and energy from that?
Itself. Read the threads on Energy, Mass and Why c is the limit.

Farsight
Posts: 437
Joined: Mon Mar 08, 2010 10:52 am
Contact:

Re: Understanding electromagnetism

Post by Farsight » Mon May 31, 2010 3:26 pm

Twiglet wrote:
Farsight wrote:
Twiglet wrote:Yet you are unable to solve basic mechanics problems, or understand the implications of simple problems in special relativity. Come back to me when you can.
Shrug. I've given solutions to some of your little maths tests on mistermack's thread. I've risen to your c is the limit challenge, and now you're doing a runner and being dishonest to boot. Suit yourself. But don't think people won't notice.
Heh... looking up a formula and plugging numbers into it you mean? Sure, you obtained a correct numerical result. Well done etc. A shame the conceptual meaning of that result is still beyond you.
No it isn't beyond me. The Lorentz factor comes from Pythagoras' theorem, see Simple inference of time dilation due to relative velocity. The hypotenuse is the light path of length 1 because we're using natural unit where c=1, the base is your speed as a fraction of c, and the height is the time dilation / length contraction factor, with a reciprocal because one's a dilation and one's a contraction.
Twiglet wrote:You didn't solve any of the mechanics problems, or even attempt to do so. You didn't understand the result of the relativity problem you numerically solved plugging in numbers from a printed formula you don't conceptually understand.
You're ducking and diving and clutching at dishonest straws Twiglet. I can do the maths, and I understand it.
Twiglet wrote:As for honesty, thats easily judged farsight, because I confined my discussion to a level where you utter failures are glaringly obvious to the audience following these threads. They aren't PhD stuff, they are A level stuff. And you are stuffing it up. No amount of linguistic argument is going to win popular support for you. The genie is out of the bottle.
LOL, I got those answers right. Everybody knows I got them right. And everybody knows what that makes you.

User avatar
normal
!
!
Posts: 9071
Joined: Thu Mar 26, 2009 4:23 pm
About me: meh
Location: North, and then some
Contact:

Re: Understanding electromagnetism

Post by normal » Mon May 31, 2010 3:32 pm

Well.... Your mother!
Image
Let us think the unthinkable, let us do the undoable, let us prepare to grapple with the ineffable itself, and see if we may not eff it after all.
                                                                                                                                                                                                                   -Douglas Adams

lpetrich
Posts: 303
Joined: Wed Feb 24, 2010 8:59 pm
Contact:

Re: Understanding electromagnetism

Post by lpetrich » Mon May 31, 2010 10:57 pm

Farsight wrote:
lpetrich wrote:[Why don't you read that Wikibooks introduction to special relativity?
Because I'm way past that level.
Farsight, that's a VERY dumb excuse. SR has been VERY well tested, and you ought to make yourself familiar with it. Otherwise, your attempts to construct a theory that includes it will result in failure.
Farsight wrote:And the speed of light is not constant. Einstein said so, and the scientific evidence says so.
Pure proof-texting. The Michelson-Morley experiment and similar ones set some rather strong limits on local Lorentz invariance, meaning that the speed of light in a vacuum is locally constant.
Your disdain for experimental evidence is a throwback to crystal spheres.
:funny:
Your interpretations are laughable, and you have yet to show why mainstream physics cannot account for the phenomena that you cite.
Ipetrich wrote:Can you work out the numbers? Like how momentum and energy increase with velocity.
Of course I can. Ask me on the appropriate thread.
Whatever it is.
Ipetrich wrote:What makes the light go in circles? How do you get relativistic momentum and energy from that?
Itself. Read the threads on Energy, Mass and Why c is the limit.
[/quote]
OK, but you have yet to derive that formula in any of them.

User avatar
colubridae
Custom Rank: Rank
Posts: 2771
Joined: Thu Feb 25, 2010 12:16 pm
About me: http://www.essentialart.com/acatalog/Ed ... Stars.html
Location: Birmingham art gallery
Contact:

Re: Understanding electromagnetism

Post by colubridae » Tue Jun 01, 2010 7:47 am

Edit sorry posted to wrong thread see 'jimc maths probs'
I have a well balanced personality. I've got chips on both shoulders

User avatar
Tigger
1,000,000,000,000,000,000,000 piccolos
Posts: 15714
Joined: Thu Feb 26, 2009 4:26 pm
About me: It's not "about" me, it's exactly me.
Location: location location.

Re: Understanding electromagnetism

Post by Tigger » Tue Jun 01, 2010 8:37 am

colubridae wrote:Edit sorry posted to wrong thread see 'jimc maths probs'
Wormhole?
Image
Seth wrote:Fuck that, I like opening Pandora's box and shoving my tool inside it

Post Reply

Who is online

Users browsing this forum: No registered users and 3 guests