Explain Constants.

[arkain101]

Awhile ago I started a topic about explaining mass and got alot of amazing replies. In fact it led me to an idea of how to actually EXPLAIN it. Which I am tying to work on.

 

This ended up leading me to thinking of a version of how to explain constants. Why the speed of light is what it is and why the constant actually exists in the first place. Also, the cause and effect of doppler shift.

 

 

We begin by looking at how a constant can come about in the first place. Why do we need it? Why is there?

Scientific data shows light travels at what we call C, which comes from the word Celeritas, a greek word for swiftness. :eek:

 

In this universe of space-time there is motion and it is what underlies the reason things happen.

Light is a motion. It is frequencies and it is measured to have wave length.

 

This here is the KEY to explaining the constant.

 

The actual value of C is not what is important to consider at this moment. The specific value of C I would think must come from some thing that is fundamental in our universe.

 

However, even if we changed the actual value of C, there would still be the inevitable constant!

 

The reason for this comes from looking at electromagnetic radiation and frequencies. A frequency is either ON or it is not. The actual details of a frequency can change, but most importantly they can only be contained and exist inside a specific constant relative to the originating velocity source.

 

To explain this in more detail lets look at an example.(Using the conveyor belt analogy.)

 

If we imagine that light's velocity is like a conveyor belt and each wave front of light is a pebble dropped onto the conveyor. That pebble will travel along on the conveyor at the velocity it is at and deliver the pebble to reciever at that specific velocity.

 

The frequency of the light (pebbles) is the time between each pebble that is dropped onto the conveyor aswell as the amount of pebbles per 'time' that reach the recieving end of the conveyor.

 

The distance between each pebble is like the wavelength of the light waves. Wavelength is directly perportional to the velocity of the belt and the frequency of dropped pebbles. These three things ; conveyor constant, frequency, and wavelength are in a fixed relationship. Constant = Hz * WL (frequency(hertz) times wavelength(WL)).

 

Finally, the velocity of the light is the conveyer belt itself.

 

Now, regardless of the velocity this belt (light) travels, a remarkable notion needs to be paid attention to.

 

The pebbles can not stop being dropped or the frequency is ended and this is forbidden in terms of what is being discussed.

 

Light is always in motion, space-time cannot stop motion.

 

Importantly, the pebbles can only be dropped to a specific rate before the frequency becomes anialated from zero wavelength (zero distance between pebbles).

 

Because light is measured to be 300,000,000m/s, the frequencies can only be made inside this window of opportunity. From radio waves all the way up to gamma rays, the frequency can be low with large wave length or, the frequency can be high with short wavelength. To note, the frequency can not be zero and the wavelength can not be zero.

 

So, if we were to add pebbles to the belt at faster and faster rates we have to work harder and harder to do so. Thus, put more energy into the pebbles (more energy in the wave fronts).

 

If we put them down so fast that we are literally pouring the bag of pebbles on the belt we get a stream of pebbles, one lined up behind another. No longer is there a frequency. No frequency is space-time is somewhat of a forbbiden concept in this respect.

 

What is quite useful is we can observe and calculate this with relatavistic doppler effect.

 

If the observer and the source are moving directly away from each other with velocity v , the observed frequency Fo is different from the frequency of the source Fs as;

 

where c is the speed of light.

 

 

 

This equation calculates the change in frequency (redshift) we get with objects moving in space in direct line of sight of eachother at specific velocities.

 

Now, we can enter values of v which is the velocity of which one of the objects are moving relative to one another and find the new frequency.

 

Now when we enter the velocity of an object to reach C.. it will show that the light frequency will be elminated, which can not happen!

 

fo= sqrt [(1-v/c)/(1+v/c)fs]

 

fo= sqrt [(1-c/c)/(1+c/c)fs]

 

fo= sqrt [(1-1)/(1+1)fs]

 

fo= sqrt [(0)/(2)fs]

 

fo= sqrt [0fs]

 

fo= sqrt [0]

 

fo= 0

 

 

When an object travels towards the speed of light the frequency of the light from sources directly infront of it increase in respect to the originating constant value. An object traveling up to the actual velocity of light itself will create a product of zero wavelength of the energy coming infront of you which stops the frequency. Aswell as causing energy with zero frequencies behind you from sources parrallel in line of travel.

 

This can not be done. Which is another reason to back up why C is the proposed cosmological speed limit.

 

So we now arrive at summerizing why a constant exists in the first place.

 

The universe functions on frequency and motion. So, whatever the velocity works out to for source, there lies a cosmological speed limit for a reason. It is inevitable for a constant to arise out of a realm with frequencies as the basis of its function.

 

 

 

At this point I will have to leave it here.

[Turtle]

Awhile ago I started a topic about explaining mass and got alot of amazing replies. In fact it led me to an idea of how to actually EXPLAIN it. Which I am tying to work on....

 

This ended up leading me to thinking of a version of how to explain constants....

 

The Fine Structure Constant is variable within limits. (Sorry all you 137 numerology fans; as if 137 weren't already rounded.:eek: )

 

http://en.wikipedia.org/wiki/Fine_structure_constant

Recent improvements in astronomical techniques brought first hints in 2001 that in fact might change its value over time. (For a brief article see (1) ). However in recent years several experiments have put increasing tighter limits on the variability of over time. In April 2004, the first set of new and more-detailed observations on quasars made using the UVES spectrograph on Kueyen, one of the 8.2-m telescopes of ESO's Very Large Telescope array at Paranal (Chile), puts limits to any change in at 0.6 parts per million over the past ten billion years.

[cwes99_03]

Actually c is a constant based on constants mu and I believe epsilon, anyway they are the permeativity and permutivity of space? Anyone want to check on that little bit of fact for me. I don't have time right now.

Gotta run.

[Erasmus00]

Actually c is a constant based on constants mu and I believe epsilon, anyway they are the permeativity and permutivity of space? Anyone want to check on that little bit of fact for me. I don't have time right now.

 

This is only true in SI, which sort of obscures the real meaning of the constant c. I think in a more unit independant way you could define c as the ratio of electric to magnetic field strength.

-Will

[Qfwfq]

The real meaning of c is just the ratio between the unit of "length" chosen for timelike directions and that chosen for spacelike ones. Use the same unit for both, and you have c = 1 as God commands. One second is a length approximately equal to three hundred million metres.

[cwes99_03]

You may believe that to be true. But here we are talking about the fundamental underlying constants behind c, not what we measure c to be. Take an E&M class and they should teach you where c is derived from. Maxwell's equations are all you need.

[Qfwfq]

Take an E&M class and they should teach you where c is derived from.

Are you sure it isn't the other way around?

[cwes99_03]

Yah, it isn't necessarily obvious, but that is why this thread was started. Most people are taught in high school or what have you that c is a universal constant, but once one derives maxwell's equations you will realize that two other constants that are completely physical are what compose the constant c.

[Farsight]

Could you give me a pointer to that, cwes?

 

I'm interested because we were talking about kinetic energy on another thread, and it appears to be a relative Mass and Velocity property rather than something real in its own right.

[Erasmus00]

Yah, it isn't necessarily obvious, but that is why this thread was started. Most people are taught in high school or what have you that c is a universal constant, but once one derives maxwell's equations you will realize that two other constants that are completely physical are what compose the constant c.

 

You CAN define c the way you are describing, with a ratio of magnetic to electric field strengths. HOWEVER, if you start from relativity by defining c in the way proposed by Q, then you can build up Maxwell's equations from first principles (a minimal action principle coupled with relativity, and the experimental constraint that fields are linear). See for instance, Landau and Lifshitz Classical Theory of Fields. Personally, I find this approach more fundamental.

-Will

[cwes99_03]

Hmm, i missed something in Q's post and yours here. How do you derive Maxwell's equations from a simple knowledge that c is defined by length and time? Besides, we weren't talking about defining time, but the underlying constants that make the constant time. As far as I know there is no universal constant of length or time, but there are of permittivity and permeability.

 

So I found a reliable web source to show the equational relationship between c mu and epsilon.

 

http://www.fnal.gov/pub/inquiring/more/light/light_page9.html

 

Couple this with http://en.wikipedia.org/wiki/Permittivity, and http://en.wikipedia.org/wiki/Permeability_(electromagnetism) and you'll understand why c stems from these constants.

 

I'll look up that reference, Will.

[Farsight]

Thankyou cwes, I shall study.

[Qfwfq]

How do you derive Maxwell's equations from a simple knowledge that c is defined by length and time?

The way he said, and the text he mentions is a good example of the formal approach boiled down to the essence.

 

If you're competent in EM, surely you've seen the D'Alambert equations derived from Maxwell's. Have you never wondered why they seem so especially made for special relativity? OTOH, why in the first place were Michelson and Morely so frantically trying to detect differences in the velocity of light according to direction?

 

As far as I know there is no universal constant of length or time

Indeed, that wasn't the point. I believe that's the root of your misunderstanding.