Mr. Sammi

Oxymoron,

I read somewhere that experimental research on the 4th generation synchrotron devices may yield a coherent light source due to some sort of photon overlapping or some thing like that?

do you have any idea about this? Or am I completely off.

This synchrotron light is obtained when hi-speed electrons are bent by a magnetic field...

Sammi Na Boodie ()

Mr. Sammi

Oxymoron,

I would suppose that in system if two components are directly linked to each other varying one component invariably changes the other. These would be tightly coupled components.

Weakly coupled components are those where the primary component generates an effect and the secondary component is apparent. These secondary components are unlikely to affect the primary component when varied.


Sammi Na Boodie ()

Oxymoron

One must be very careful. What we consider to be "particles" (hadrons, leptons, etc) can also be modelled as "waves". Symmetrically, light - classically modelled as a wave - can be modelled as a stream of "particles" (photons). None of this makes the claim that light (or matter) is a wave or is a particle; only that when we model quantum phenomena as particles, that's how they act; when we model them as waves, that's how they act.

Nah, I'm (a) too modest, and (b) I've been writing software for too long

I presume you mean the orbital magnetic moment of an electron? Technically, it's q*L/2m where q is the charge, L is the angular momentum, m is the electron's mass (L=m*v*r).

Mr. Sammi

Oxymoron,

Do you know if in some forms of EM, it is possible to increase speed by the influence of magnetic flux?

Does it have a direct impact? Or does itz orthogonality forbid it from doing so?

I do not really know. Mabye I am just thinking-guessing-enquiring!


Sammi Na Boodie ()

Osm bsm Y.

i always understood (incorrectly ) that particles had spin like a baton spinning through space and that what we saw as the waves were caused by the polarity of the particle as it spun end of end...positive over negative. i'll have to learn the newer ideas.


let me change this in light of particles being not what i thought they were. what about the outside edges of the smallest matter that can be thought capable or rotating classically. isn't there a problem with rotation on the smallest level when we say that motion is quantized? how can there be differences in velocity from the outside in toward the axis of rotation on very small masses?

if twirl a stick, somewhere at the middle of this stick's axis of rotation is an atom nearly exactly on the axis. isn't this atom turning with the stick? or would we say that the atom's are essentially stay oriented the same way and only their fields are rotating?


thx very much. i'm am definitely learning here. i'm worried a little about plank's constant. how was this founded and how can we know the amount of light emitted in 3 dimensions by a large body of light? is that based on the mass of the star? how can we know the mass of a star? is that based on the light it emits? how do we know how much light.... see? this is the source of my confusion with our measures, i'm overlooking something if someone can help me please.

not sure i follow here. could it maybe be thought of as a train going by? where we are standing still on the ground and measuring the distance between each car going by...the train is going at the speed of light and we are seeing each car...maybe a red then blue then red then blue car going by...and we calculate waves something like that? if i'm off here tell me i want to understand. =(

Oxymoron

As an (ex-) astronomer, synchrotron radiation is familiar. This 4th gen stuff is wierd, as synchrotron is usually high-energy radiation. I've no idea what "photon overlapping" is, though.

Friar Bellows

I underestimated the number of photons emitted by the Sun every second because I only counted the photons in the visual band of the spectrum. The Sum emits a lot of stuff in the infrared as well as other parts of the spectrum.

So am I.

Planck and Einstein were the first as far as I know. Planck with his blackbody law and Einstein explaining the photoelectric effect. Look those terms up in a physics textbook or on the internet.

First we measure how much light we receive from the source. Then we work out how far away we are from the source of light. And often we have to work out how much extinction there is between us and the source of light. That is enough. Measuring distances to objects in space is a big job. For extragalactic distances, read this article:

A Critical Review of Selected Techniques for Measuring Extragalactic Distances by Jacoby et. al. (1992)

Shadowy Man

Don't think in terms of actual rotation. Like I said, using the word "spin" just confuses the issue. If I told you that a photon has 1 unit of spin and an electron 1/2, would you be further confused.

Do a web search on "ultraviolet catastrophe".

Well, you measure the flux on a detector at the Earth. If you know the distance to the object you can calculate the Luminosity at the wavelength you detect. If you know the spectral energy distribution, you can calculate the total luminosity.

Yes, the more massive a star is, the more light it puts out. Also, the hotter it is, and thus the peak of its emission shifts toward the ultraviolet.

There is a very good relationship between a star's spectral type and its mass. The spectral type is determined by looking at the presence and strength of various absorption lines in its spectrum and/or its broad-band colors. Luckily there are many binary systems out there, so determining the masses of stars can be done through their orbits around other stars (assuming of course that Kepler's laws apply there).

Hopefully I've cleared some of that up. Feel free to ask more questions.

-Shadowy

Undercurrent

But, in QM there is an additional magnetic moment that an electron has just for being an electron, without needing to be bound in an orbit(al) to an atom. It's through this magnetic moment that we detect the intrinsic "spin" of an electron.

I suppose that's an important distinction, that when we talk about electron spin, we are not saying, "an electron is an extended body that rotates," but "the electron has an intrinisic magnetic moment that formally looks like the magnetic moment of a spinning extended body without the electron actually being one."

Quantum mechanical spin is related to quantum mechanical orbital angular momentum, but only through being represented by different solutions to the same set of operator commutation equations (read: at a very abstract level which non many people really understand, myself included.)

Shadowy Man

Yes, electron spin and angular orbital momentum are two different things, though they can interact, ala the spin-orbit coupling term in an atomic Hamiltonian.