Dark matter?

[dedndave]

as for the electrons "flowing" in a wire
when i was in college - lol - 30 years ago....
they weren't sure if the electrons actually traveled from one atom to the next, or just the field of charge
i suppose that has been answered, by now

but - if the mass moves, it is replaced by the mass of the electron that replaces it
otherwise, we might see wires jump when you flip a switch   :bg
it takes a complete circuit for current to flow

[baltoro]

STEVE (aka, FORTRANS),
You clearly know what you are talking about,...(my understanding of the subject is nebulous at best),...
Here are a couple of papers which you (and other General Relativity fans) might find informative:   

Is General Relativity 'Essentially Understood' ?, 2008   
What Was Einstein's Principle of Equivalence ?
Einstein's Bumpy Road to General Relativity, 2005

...And, if you have an IQ higher than Spock's,...and, are thinking seriously about space travel,...you'll love this overview:   
Relativistic Reference Frames for Astrometry and Navigation in the Solar System, 2006

[FORTRANS]

Hi,

   A static charge would change the number of electrons.  How
much does a lightning bolt weigh?  I guess a better example
would be the electron beam in a CRT.  Does anyone worry
about the gravitational field of that?

   Flowing electrons.  How could you move the field without
moving the electrons?  Anyway, I read an article a while back
where they were showing how some electromagnetic property
was caused by relativistic effects of the electrons velocity.
The electrons in one wire were "seeing" the ones in another
wire getting closer together due to relativistic foreshortening.
So they apparently thought the electrons were moving.

Cheers,

Steve N.

[dedndave]

A static charge would change the number of electrons.
How much does a lightning bolt weigh?

they must be very heavy - they always come down   :U

I guess a better example would be the electron beam in a CRT.
Does anyone worry about the gravitational field of that?

i can tell you from personal experience that the electrical field is what you have to worry about
it will set you on your ass   :lol

http://www.physicsclassroom.com/class/circuits/u9l2c.cfm

[FORTRANS]

Hi,

   Thanks for the suggested links baltoro.  Too bad my attention
span and difficulty in reading from a monitor only allowed for a
few pages of each of the first three.  Heady stuff,

Regards,

Steve

[hutch--]

 :bg

there is an alternative to DARK MATTER, its GREY MATTER (GRAY MATTER for our friends in the US) but sad to say we don't see much of it these days.  :P

[Bill Cravener]

Steve,

That was what I tried to imply in my first post to Farabi, that is to say, the older I become the more dark matter (dead brain cells) I acquirer. I think my comment passed over most heads though. :bg

[FORTRANS]

Hi Bill,

   It was subtle, but not overly so.  (IMO)

Cheers,

Steve N.

[daydreamer]

all planets you cannot see, doesnt those count as dark matter and all life on planets is using energy to live but not enough to be seen from other stars, doesnt that count as dark energy?

[vanjast]

If E=MC^2 is anything to go by...

E= energy.... you cannot see most of it, It has mass and wavelength.
Anything with a wavelength has mass and energy..etc..
It's a simple observation that is right in front of our noses. There's your 'dark' matter

An extension to mass is that it 'has' gravity, therefore gravity is also dark matter, energy and wavelength... and visa versa.

Maybe I should stop before I make the world's top theoretical physisists look like 'turkeys'... :bg

[dedndave]

i'm not sure we can say that "energy has mass"
i think that's like jamming a square peg into a round hole

as i mentioned earlier, "matter is a state of energy"
so i suppose, when it's in that state, it does have mass

i guess i need to try and define the other states of energy
potential, kenetic - damn - i have have a puzzle with all square pieces and all round holes   :bg

[Farabi]

'm not sure we can say that "energy has mass"

Yeah, it doesnot even a catholic  :lol

[dedndave]

that's a pretty good one, Farabi   :bg

[FORTRANS]

Hi,

   Interesting pictures.

Enjoy,

Steve N.


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