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B166ER
Jul27-04, 10:57 PM
I watched the movie "The Core", in that movie they say that the earths magnetisim is based on the rotation of the earths core(molten metal spinning at high speeds) so does it have to be liquid metal or anything hot rotating at high speeds could creat a magnetic feild? is it possible to create a magnetic feild rotating some hot diodes?

NSX
Jul27-04, 11:03 PM
Any moving charge creates a magnetic field.

Antonio Lao
Jul27-04, 11:18 PM
Magnetic field is also produced from displacement current. The time rate of change of electric flux density, D.

\vec{J_d} = \frac{\partial \vec{D}}{\partial t}

B166ER
Jul28-04, 01:28 PM
so is it possible to create your own earth in a contained facility? is that even possible?

Antonio Lao
Jul28-04, 02:01 PM
so is it possible to create your own earth

To do that you have to permanently borrow a lot of energy from the vacuum. The vacuum is an infinite energy bank. Energy can be borrowed but only for a very short time. But you can also fool the energy bank of the vacuum by using the Higgs mechanism of broken symmetry hence transforming virtual fermions (quarks and leptons) and virtual bosons permanently to real fermions and bosons.

A better practical use for these borrowed energies would be to disintegrate an incoming asteroid on a collision course with our earth.

Epsilon Pi
Jul28-04, 02:06 PM
Hi Antonio,

I thought displacement current was a theoretical concept introduced to preserve the symmetry in Maxwell equations. Could you please give us a physical example of the production of a magnetic field by such a theoretical concept?

Regards

EP
Magnetic field is also produced from displacement current. The time rate of change of electric flux density, D.

\vec{J_d} = \frac{\partial \vec{D}}{\partial t}

B166ER
Jul28-04, 02:32 PM
what are quarks and leptons? im sorry for so many questions i am just beginning to get into the field of physics.

thank regards

Antonio Lao
Jul28-04, 02:41 PM
to conserve the simetry in Maxwell equations

The symmetry of Maxwell's equations are the change in space of one field (electric or magnetic)being proportional to the change in time of the other field and vice versa.

But from Faraday's experimental results, there is no such symmetry because the time rate of change of charge must be zero (the divergence of the curl is zero) so that the change in space of magnetic field has no corresponding change in time for electric field. Maxwell just added the term of displacement current as the time rate of change of electric field into the equation. The outcomes are the wave equations for magnetic and electric field for classical electromagnetic radiation.

Epsilon Pi
Jul28-04, 02:47 PM
So there is no such thing as the production of a magnetic field by such a theoretical concept as the displacement current, right? This was my point
Regards

EP
PD: As a matter of fact, there are other ways to explain the classical electromagnetic radiation

The symmetry of Maxwell's equations are the change in space of one field (electric or magnetic)being proportional to the change in time of the other field and vice versa.

But from Faraday's experimental results, there is no such symmetry because the time rate of change of charge must be zero (the divergence of the curl is zero) so that the change in space of magnetic field has no corresponding change in time for electric field. Maxwell just added the term of displacement current as the time rate of change of electric field into the equation. The outcomes are the wave equations for magnetic and electric field for classical electromagnetic radiation.

Antonio Lao
Jul28-04, 02:56 PM
what are quarks and leptons?

the stuff that matter is made of. There are 3 generations of quarks and leptons.

1st generation is the leptons called electron and the associated electron neutrino, the quarks called up and down.
2nd generation is the lepton called muon and its associated neutrino, the quarks called strange and charm.
3rd generation is the lepton called tau with its neutrino also, the quarks called bottom and top.

I think, all these quarks and leptons have been discovered by now, seen by experiments.

ordinary atoms is made mainly from the 1st generation of quarks and leptons.
The proton is made of 2 up quarks and 1 down quark. The neutron is made of 2 down quarks and 1 up quark.

The simplest atom of hydrogen is made of 1 proton and 1 electron. The isotope of hydrogen called deuterium is made of 1 proton, 1 neutron, 1 electron. The rest of the chemical elements in the periodic table are all made of multiple numbers of these 3 basic particles (proton, neutron and electron).

B166ER
Jul28-04, 02:58 PM
is the quark and lepton theory actual fact or theory?

Antonio Lao
Jul28-04, 03:13 PM
there are other ways to explain the classical electromagnetic radiation

Please enlighten me on these.

fact or theory/

It's a fact. They are all discovered and seen by experiments.

B166ER
Jul28-04, 03:17 PM
is it posible to conduct these expirements at home?

Antonio Lao
Jul28-04, 03:45 PM
is it posible to conduct these expirements at home?

Not unless your home is inside Fermilab or CERN.

Epsilon Pi
Jul28-04, 06:50 PM
Hi Antonio,

Before going on I want to ask you kindly two questions:

1-First of all, a radiation is a wave isn't it?
2-Complex numbers are a fundamental tool for electromagnetism, right?

EP

[QUOTE=Antonio Lao]Please enlighten me on these.

Antonio Lao
Jul28-04, 08:15 PM
1-First of all, a radiation is a wave isn't it?
2-Complex numbers are a fundamental tool for electromagnetism, right?


1. Classically, the total energy of the electromagnetic wave is given by the volume integral

\frac{1}{2} \int \int \int \left(\vec{B} \cdot \vec{H} + \vec{D} \cdot \vec{E}\right) dxdydz

And by the introduction of the scalar and vector potentials, the wave equation is used for both in finding solutions to waves propagations.

2. Optionally, using Euler's formula, relating complex numbers to the trigonometric functions, making Fourier series and coefficients in complex notations.

Epsilon Pi
Jul29-04, 06:50 AM
1. With your first answer I assume you say yes, regarding my question about the wave nature of electromagnetic radiation that was my point.
2. In the second one you make reference to Euler relation, on which complex numbers are based, that as a matter of fact is the only mathematical equation that remains with the same form with derivation and integration -except for the symbol i that means that the complex plane is the background of those proccesses-... this isomorphic property makes it posible to express differential equations as simple algebraic equations, the "bread and butter" of IE, and furthemore this ER is precisely a wave equation, whose cosine term expresses an even symmetry and its sine an odd symmetry, so it is an ideal expression for expressing the fundamental equations of physics, and as such its profound duality, of space-time, particle-wave, ect.

Isn't this ER ideal for solving the so-called, incommensurability of paradigms, I mean that conflict between QM and GTR?

Regards

EP

1. Classically, the total energy of the electromagnetic wave is given by the volume integral

\frac{1}{2} \int \int \int \left(\vec{B} \cdot \vec{H} + \vec{D} \cdot \vec{E}\right) dxdydz

And by the introduction of the scalar and vector potentials, the wave equation is used for both in finding solutions to waves propagations.

2. Optionally, using Euler's formula, relating complex numbers to the trigonometric functions, making Fourier series and coefficients in complex notations.

Antonio Lao
Jul29-04, 08:14 AM
yes, regarding my question about the wave nature of electromagnetic radiation

1. Partially, yes. The quantum theory of radiation gives the energy as E = h \nu.

incommensurability of paradigms

2. What space dimension you have in mind?

Epsilon Pi
Jul29-04, 08:48 AM
1. was not that equation the beginning of non-classical physics?
2. ...space dimension?

Regards
EP
1. Partially, yes. The quantum theory of radiation gives the energy as E = h \nu.



2. What space dimension you have in mind?

Antonio Lao
Jul29-04, 10:38 AM
1. was not that equation the beginning of non-classical physics?
2. ...space dimension?

1. Empirically, Planck derived the equation but could never have the heart and mind to fully accept its subsequent implication in the development of quantum theory, quantum mechanics and then quantum field theory.

2. The ratio of sine function to cosine function (tangent function) is really half the area of an arbitrary triangle. And the minimum area configuration is really an isosceles triangle of base 1 and altitude 1 giving area 1/2. The space dimension of area is 2 and as the theory of surfaces.

Epsilon Pi
Jul29-04, 01:21 PM
Amen

Regards

EP
1. Empirically, Planck derived the equation but could never have the heart and mind to fully accept its subsequent implication in the development of quantum theory, quantum mechanics and then quantum field theory.

2. The ratio of sine function to cosine function (tangent function) is really half the area of an arbitrary triangle. And the minimum area configuration is really an isosceles triangle of base 1 and altitude 1 giving area 1/2. The space dimension of area is 2 and as the theory of surfaces.