matter made of space not energy?

[maddog]

Originally Posted by WebFeet

The speed is then dependant on the medium through which it is traveling.
In the experiment you mention,is light being slowed down or has its arrival at the end point merely been delayed?

Yes, the speed of light is medium dependent. However the constant c (speed of light in a vauum) is
invariant (current models). I don't understand the delayed comment. You couldn't go the distance and
then do a "three count" at the end, unless you plan to throw out relativity.

Originally Posted by WebFeet

Do photons get created ?
Energy can neither be created nor destroyed

Yes, photons get created all the time. Consider an electron in a valance shell of an atom. It absorbs a
photon. This raises the energy of the electron to higher orbital. Later when it emits another photon it
may go back to that orbital or go to another lower energy level. This is all part of QED invented by
Feynman (1947).

Originally Posted by WebFeet

Assuming a photon to be pure energy, this would imply that rather than it being created, it was there all along. Maybe as part of a more complex structure, such as the electron. If it were a component of the electron, then it would follow that it should maintain it properties while part of the electron, in other words it maintains its constant velocity within the structure of the electron. When it is released from the electron structure, it flies off at the only velocity it knows- the speed of light.
Throw an electron and a positron at each other, the result is two photons.

I grant you electrons may not be point particles and have some internal structure smaller than can be
discrerned at the moment. It has nothing to do with the preservation/destruction of photons. I don't
think you understand what is actually going on. Find a book like Tao of Physics or Dancing Wu Li Masters.
These are good popular books on explaining this and related subjects.

Maddog

[WebFeet]

Originally Posted by maddog

I don't understand the delayed comment. You couldn't go the distance and
then do a "three count" at the end, unless you plan to throw out relativity.

The comment was to do with the experiment that apparently slows light. The delay being due to the refractive index of the medium being used.

Originally Posted by maddog

Yes, photons get created all the time. Consider an electron in a valance shell of an atom. It absorbs a photon. This raises the energy of the electron to higher orbital. Later when it emits another photon it may go back to that orbital or go to another lower energy level. This is all part of QED invented by Feynman (1947).

Wouldn't it be more accurate to say that photons are detected rather than created. There is no proof either way that when the photon is absorbed into the eletron that it is destroyed, and it would have to be if it were later to be created.

Originally Posted by maddog

I grant you electrons may not be point particles and have some internal structure smaller than can be discrerned at the moment. It has nothing to do with the preservation/destruction of photons. I don't think you understand what is actually going on.

If the photon is not destroyed when it is absorbed, then when it is detected leaving the electron, there is no need to imply that it magically reaches its invariant velocity, but rather that it maintained its velocity whilst a component of the electron.
The speed of light is the speed of energy. There is nothing to say that the energy absorbed by the electron doesn't continue travelling at the speed of energy while it is part of the electron. It has simply lost its individual identity as a photon because it has become part of system that is an electron.

[Tormod]

Originally Posted by WebFeet

The comment was to do with the experiment that apparently slows light. The delay being due to the refractive index of the medium being used.

It is not an apparent effect. You need to read up on this if you are to keep arguing your points.

Here is a news story of interest. Make sure you read ALL of it.
http://www.msnbc.com/news/242698.asp?cp1=1

Wouldn't it be more accurate to say that photons are detected rather than created. There is no proof either way that when the photon is absorbed into the eletron that it is destroyed, and it would have to be if it were later to be created.

What is the purpose of this argument? When an electron is excited, say, by an incoming photon, it absorbs that photon as pur energy and the extra energy makes the electron jump one step closer to the nucleus. The exact opposite happens when the electron gets exited and steps up the ladder: a photon is emitted.

In effect, the electron has no changed. It is no longer the same electron. Both the photon and the elextron have changed into new particles. Both interactions require that the electron is equal in all proerties except energy level. The photon is destroyed in the first example and created instantly in the other example.

Here is perhaps an easier explanation:
http://curious.astro.cornell.edu/question.php?number=85

The speed of light is the speed of energy. There is nothing to say that the energy absorbed by the electron doesn't continue travelling at the speed of energy while it is part of the electron. It has simply lost its individual identity as a photon because it has become part of system that is an electron.

The electron is a fundamental particle in the Standard Model and as such does not contain photons. In fact, I am not aware of any particles that contain photons, either. Photons are always destoryed or created as a result of particle interactions. They are not "swallowed up".

But why do you want the photon to remain inside the electron? Or any other subatomic particle for that matter? If you want to see at as being carried further then I guess you could hypothesise that it happens but it would be interesting to see what sort of predictions you can make out of this.

[WebFeet]

Originally Posted by Tormod

It absorbs that photon as pur energy and the extra energy makes the electron jump one step closer to the nucleus.

Shouldn't that be the other way round ?

Originally Posted by Tormod

But why do you want the photon to remain inside the electron? Or any other subatomic particle for that matter? If you want to see at as being carried further then I guess you could hypothesise that it happens but it would be interesting to see what sort of predictions you can make out of this.

A 0.511-MeV photon has the same amount of energy as an electron, or for that matter a positron. In fact when an electron and a positron mutually annihilate each other, the result is two 0.511-MeV photons.
No matter what particle you are playing with, when you annihilate it you end up with a handful of photons. All the mass, charge, and other properties are gone - if they haven't, you haven't completely annihilated it.

If you view the electron itself as a system, rather than as a component of an atom, you will see that based on above annihilation example the only component to the electron is energy (photons). There are no other mythical particles that appear after this annihiliation, only photons.
Within the realm of this electron system there are additional properties. Additional to those imparted on it by the photons. These include mass and charge. The amount of energy remains constant.
All of the components loose their individual identities and become part of the system. This doesn't mean that the components have been destroyed, just that they become part of a larger system. When they exit from the system, they regain their individual identities, and the system looses something of its properties.

If energy (photon) is the one and only fundemental building block of our Universe, then it can only be built upwards. It can't be destroyed - conservation law. It can't be created - same law.
It also provides the most basic set of rules to which everything else must conform. Why is the speed of light so fundemental, even when we are not actually dealing with light?

[lindagarrette]

I found this big letter web site that's pretty good at the elementary level -- that's me.

http://www.colorado.edu/physics/2000...debroglie.html

[maddog]

Originally Posted by humility

If you look at my original post I agree with Thelonius I say that mass can't be converted to energy.

Huh? Mass converts easy enough. Consider annihilation of an electron with a positron. This reaction
produces [a pair] of Gamma Rays in opposite directions [to preserve angular momentum]. This is one
case of total conversion. Consider heating up a material. In QM the "heat" is actually IR photons being
absorbed by particles (often electrons) in the material. The additional energy becomes kinetic energy for
the absorbing particle.

Originally Posted by humility

If you look at the lorentz transformations equations they say the dimensions of space decrease as you approach the speed of light and time intervals increase. You can't travel at the speed of light because there is no dimension of space to travel through. That is why the speed of light is a velocity barrier.Its more the limit of spacial dimension and hence velocity than the speed of light. Light therefore sits exactly where space ceases to exist and time becomes infinite. ...

I couldn't actually quote this whole thing as a waste of bandwidth. So I will only address the bold parts (&
ignore the rest). It appears you use "dimension" in a misleading fashion. Don't you mean the scale of that
coordinate, say [x] is expanded because of the Lorentz Transmformation ? Seem ludicrous to say that
"as a particle approaches the speed of light" [assuming a mass particle] that it's "dimensionality is lessoned
(say from 3 dimensions to 2). If no dimension for space, where did it go ? ???

Maddog

[humility]

Mad dog what is ludicrous is your inability to grasp a simple concept. The fact that you might of miss interpreted the equations through a lack of conceptual ability and are hiding behind the belief that you understand the math and it doesn't matter if it makes any sense in the real world. I bet you think the big bang theory is perfectly logical. HAHA fool.

[WebFeet]

Originally Posted by lindagarrette

I found this big letter web site that's pretty good at the elementary level -- that's me.

Wave energy levels rather than orbiting particles makes a lot more sense. Each absorbed photon,rather than being destroyed, merely adds to the total energy of the wave, and subsequently to its frequency.
It would appear that the electron consists of little more than a stream of photons circling the nucleus, the distance determined by the frequency.

If this is true for the electron, then it would seem appropriate that its proton pair should follow along the same lines.

Is the atom no more than a complex configuration of photons ?

[Tormod]

Originally Posted by humility

Mad dog what is ludicrous is your inability to grasp a simple concept. The fact that you might of miss interpreted the equations through a lack of conceptual ability and are hiding behind the belief that you understand the math and it doesn't matter if it makes any sense in the real world. I bet you think the big bang theory is perfectly logical. HAHA fool.

This is a moderator warning: You have violated our FAQ on several accounts in this single post. Edit it immediately or I will place a ban on your account here at Hypography.

[Tormod]

Originally Posted by WebFeet

Shouldn't that be the other way round ?

Ah, yes, probably. Sorry. Lying in bed with a cold...

If you view the electron itself as a system, rather than as a component of an atom, you will see that based on above annihilation example the only component to the electron is energy (photons). There are no other mythical particles that appear after this annihiliation, only photons.

I applaud your imagination, WebFeet. This is clever thinking. However, according to the standard model the electron is a fundamental particle. It is not a system.

However, if the electron WAS a system consisting of photons, then how do you explain where the electric charge of the electron comes from? I am unable to grasp that from the rest of your post. Considering that the electron retains it negative charge even when it is free (this is of course the basis of electromagnetism) then you need to explain this.

If energy (photon) is the one and only fundemental building block of our Universe, then it can only be built upwards. It can't be destroyed - conservation law. It can't be created - same law.

Photons and other particles are constantly created and annihilated in the vacuum of space. When you send a stream of electrons through a thread of carbon filament in a lightbulb, the electrons become exited and change energy levels. This causes the carbon filament to heat up and emit photons. There is nothing magical about this at all. The photons are a direct result of the heating up of the carbon.

Perhaps the most interesting bit about the photon is that it is - as far as I know - the only particle that is also it's own antiparticle.

It also provides the most basic set of rules to which everything else must conform. Why is the speed of light so fundemental, even when we are not actually dealing with light?

This is just a semantic issue. The speed of light is of course also the speed of radio waves and other electromagnetism. We are so used to saying "light" because it's the only part of the EM spectrum that we can see. The photon is the carrier of the electromagnetic interaction. It is not electromagnetism in itself, but the particle that is used when other particles interact.