A "Dark Matter" Laser ?

[LordOfLA]

Just an FYI light is made up of photons, photons are particles, particles have mass, therefore laserbeams are manipulating matter, continue on with the debate poste haste

 

[gonaads]

Man, is this like a Pokémon thing or somethin?

 

[Ohzopants]

Thanks for finding that falconguard.
This is the line that interested me the most:
"The minimum half-width of the dark spot is less than 1 m m . "

 

[falconguard]

more like a Jedi thing, Come over to the dark side...

Yeah they are using a certain kind of lense, that when used with other optics they achieve a true dark spot. Pretty Kewl stuff

 

[Ohzopants]

and LordofLA, light IS massless, this is a fact.

 

[inaminit]

The photo at the beginning of the thread has a very simple expanation. The dark streak is a shadow caused by the jet contrail being at an angle that points more towards the sun than away from it. The combined volume of the contrail is enough to block out some of the sunlight and cause the shadow. Seen it happen before.

Critical thinking, what a concept.

 

[Un4gIvEn1]

Just an FYI light is made up of photons, photons are particles, particles have mass, therefore laserbeams are manipulating matter, continue on with the debate poste haste

Actually, you may be incorrect. It is theorized that light MAY be made up of photons. It is also theorized that light may be a wave. There is no proof that shows either is correct or incorrect.

 

[Un4gIvEn1]

The photo at the beginning of the thread has a very simple expanation. The dark streak is a shadow caused by the jet contrail being at an angle that points more towards the sun than away from it. The combined volume of the contrail is enough to block out some of the sunlight and cause the shadow. Seen it happen before.

Critical thinking, what a concept.

I would have to disagree. When your friend stands in the sun, you don't see the effects of his shadow in the air. You also don't see the effects of a shadow cast by a building. If your "theory" were correct, you would see that type of effect one every city skyline across the world. You would also see that type of effect hovering below every airplane that flew overhead.

 

[inaminit]

I would have to disagree. When your friend stands in the sun, you don't see the effects of his shadow in the air. You also don't see the effects of a shadow cast by a building. If your "theory" were correct, you would see that type of effect one every city skyline across the world. You would also see that type of effect hovering below every airplane that flew overhead.

Well, actually you do. If you stand in front of me on a bright sunny day you'll see my shadow. But since I'm so much smaller than a contrail, and due to atmospheric scattering of light, the "shadow area" in the atmosphere doesn't stand out. You get the same effect as the contrail on those special days when there are clouds close together whith just enough gaps to let some sunlight through here and there. The shadows appear between the brighter rays shinning through the clouds. I think the rays are called anticircumspecular or something like that. They are seen most often at sunset or sunrise.

Here are a couple of shadows you might find interesting:
A mountain shadow in the atmosphere: http://epod.usra.edu/archive/epodviewer.php3?oid=231424

The earth's shadow: http://epod.usra.edu/archive/epodviewer.php3?oid=232448

 

[Un4gIvEn1]

Well, actually you do. If you stand in front of me on a bright sunny day you'll see my shadow. But since I'm so much smaller than a contrail, and due to atmospheric scattering of light, the "shadow area" in the atmosphere doesn't stand out. You get the same effect as the contrail on those special days when there are clouds close together whith just enough gaps to let some sunlight through here and there. The shadows appear between the brighter rays shinning through the clouds. I think the rays are called anticircumspecular or something like that. They are seen most often at sunset or sunrise.

I will retract my statement because what you say does make sense... but I don't believe it would be quite so concentrated so I believe the picture is a little photoshopped. Go stand out by your local airport some time and watch and see if this happens underneath a plane. A plane does a good job blocking light, don't you think? If you had a lot of fog or smog then it would be a little more believable.

 

[gonaads]

What is "Dark Matter"?

What is "Dark Matter" (big list).

Cool images 1 and 2.


What is "Light"?

What is "Light" for children.

 

[inaminit]

I will retract my statement because what you say does make sense... but I don't believe it would be quite so concentrated so I believe the picture is a little photoshopped. Go stand out by your local airport some time and watch and see if this happens underneath a plane. A plane does a good job blocking light, don't you think? If you had a lot of fog or smog then it would be a little more believable.

Yeah, I was just trying to find a link for that, I thought it was on the Earth Science Picture of the Day, but I couldn't find it. I have a photo of a plane's shadow, taken from the plane. It isn't a very good one though, but if you want to see it, I'll post it.

 

[vivid_vibe]

What is "Dark Matter"?

What is "Dark Matter" (big list).

What is "Light"?

What is "Light" for children.

I like the "children's" explanation best of all.

 

[Un4gIvEn1]

What is "Light"?

You should probably post from the very first page of that article instead of the link you found on google....

http://science.howstuffworks.com/light1.htm

 

[LordOfLA]

and LordofLA, light IS massless, this is a fact.

All particulate matter must have mass, however small. You should know that from school/college/university.

 

[inaminit]

All particulate matter must have mass, however small. You should know that from school/college/university.

Lay your hand flat on your desk. Count to five. Fifteen trillion neutrinos just passed through your hand. They come from the sun, and you'll get pretty much the same count day or night, because they zip right through the planet in a fraction of a second. As far as science has been able to determine they have no mass.

And light does have mass. We know this because as starlight passes by large objects it's path is slightly altered. The larger the mass of the object, (that is, a galaxy as apossed to a star), the more the bending. Thus the gravitational lensing effect predicted by Einstien's equations.

 

[gonaads]

You should probably post from the very first page of that article instead of the link you found on google....

http://science.howstuffworks.com/light1.htm

Details details...


I would hope people would actually flip the page and continue reading.

 

[gonaads]

All particulate matter must have mass, however small. You should know that from school/college/university.

You might want to read this.

Does light have mass?

Supposedly the Photon is a massless Particle. Hmmmm



[edit]
What is the Mass of a Photon?

 

[Ohzopants]

light is a wave and a particle, I've done experiments that prove both. It's called the wave-particle duality. It also applies to electrons, protons and most other subatomic particles.

LONG LIVE QUANTUM MECHANICS, WHERE CALCULUS IS KING!

 

[gonaads]

More brainy shiit

check this

and this