Unraveling the Mysteries of Faster-Than-Light Travel in Physics

[lightarrow]

But how do you think those two values were obtained in the first place? They are not obtained from any First Principles calculations. If you open the CODATA tables, you'll discover that those values totally depends on knowing what c is, and that causes you to really go in circles if you use them to get c.

This is new to me. If I missed something, please explain me, because I'm here to learn, mostly.
I have always believed we can find epsilon(0) value measuring the Coulombian force between two known charges at a known distance in the void (F=q1*q2/4(pi)epsilon(0)*r^2) or measuring the capacitance C of a plane condenser in the void, knowing S and d (S=area of plate, d = distance from plates):
C = epsilon(0)*S/d.

About mu(0): = 4(pi)*10^-7 by definition.

 

[ZapperZ]

This is new to me. If I missed something, please explain me, because I'm here to learn, mostly.
I have always believed we can find epsilon(0) value measuring the Coulombian force between two known charges at a known distance in the void (F=q1*q2/4(pi)epsilon(0)*r^2) or measuring the capacitance C of a plane condenser in the void, knowing S and d (S=area of plate, d = distance from plates):
C = epsilon(0)*S/d.

About mu(0): = 4(pi)*10^-7 by definition.

... and you could measure the value of "e", the value of "h", etc.. etc.. in several different ways. Yet, if you look at the standard, international values for these constants, they clearly define a single way in which each these values where obtained.

In the science of metrology, you want to remove, as much as possible, the intrinsic dependence of what you measure on other factors. Measuring the coulombic force isn't trivial! When was the last time were you able to measure such a thing with any degree of accuracy? And how many different assumptions do you have to make regarding your instruments and what you used to measure it?

So you may want to look up how \mu_0 and \epsilon_0 are measured currently.

Zz.

 

[Aether]

This is new to me. If I missed something, please explain me, because I'm here to learn, mostly.
I have always believed we can find epsilon(0) value measuring the Coulombian force between two known charges at a known distance in the void (F=q1*q2/4(pi)epsilon(0)*r^2) or measuring the capacitance C of a plane condenser in the void, knowing S and d (S=area of plate, d = distance from plates):
C = epsilon(0)*S/d.

About mu(0): = 4(pi)*10^-7 by definition.

The meter is the SI base unit of length/distance (square that to get the unit of area), and it is defined as "...the length of the path traveled by light in vacuum during a time interval of 1/299 792 458 of a second. " -- http://physics.nist.gov/cuu/Units/current.html

 

[lightarrow]

I know how meter is defined now. But before this definition, years ago? It was impossible to measure \epsilon_0? We are talking about the mere possibility, not about its precise measurement.

Apart this, I would like to know if you agree with me about the reasoning I made in relation of the other way to define a body's speed.

 

[DrGreg]

This is the concept: you take a train, which holds railtracks attached on top of it. You can impose a certain speed v to this train (measured in the usual way, for example); then you put another train on the first, and impose this second train's speed is still v respect the first one. You can define a new concept of speed, saying that this second train has speed 2*v relative to the ground. But, using Lorentz rule of speed addition, you have, according to the usual definition of speed, that the second train moves at a speed:
v2 = (v1+v2)/(1+v1*v2/c^2) = 2v/(1+beta^2). Repeating the same for a third train on the second and so on, you have v3,...vn. At the limit for n-->infinite, the speed is:
1.infinite, according to the new definition
2. c, according to the usual definition.

I think the concept that lightarrow is struggling to find is that of rapidity, which is defined as

c arctanh (v/c)

A speed of c corresponds to infinite rapidity. Rapidities can be added linearly, but it works only for one-dimensional motion.

 

[ZapperZ]

I know how meter is defined now. But before this definition, years ago? It was impossible to measure \epsilon_0? We are talking about the mere possibility, not about its precise measurement.

It goes just beyond the insistance of "precise measurement". It goes down to what we now believe to be a set of fundamental constants of our universe. We now know that for every measurement that we make, we depend on our knowledge of a set of fundamental constants. One or at least one of them is used in ALL measurements that we make.

So if you look carefully, nowhere are the permitivity and permeability of free space considered as fundamental constants. c is. It means that our measurement of both of those values, even your coulombic forces, implicitly depends on the value of c.

Zz.

 

[lightarrow]

Ok, thank you for your explanation ZapperZ, and the same to the others.

 

[medisaid]

the fifth dimension theory

HI
Please can you sent me your e-mail to myin:said_mohamed@hotmail.com
to make it easy for me to sent you small file (the fifth dimension theory) to hear from you about it, thank you.
Greeting feom Finland
Said Mohamed