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Black Holes???

No ,wait ..... you are not moving at less the light speed, in the diferent medium ..... you ARE moving at the light speed for that medium ..... i mean, light speed is C (299,792,458 m/s) in the void, as the void is the medium for that speed ..... light speed is, as example, only 0,75 C in water, but this means NOT that light go in water at less than it's speed, it means that light in water go at speed light in the medium "water", that is, right, 0,75 times than in the void ..... and so on.

Light always travel at light speed, is just this speed index that change in different mediums, when the group index (or optic density) changes.

By the way, there is already an experiment made with high energies, where some particles was shooted faster than light, in a medium where the light had different speed than these particles, ofcourse ..... something about Cherenkov radiations, if i recall correctly school times ..... but this, ofcourse, just cause the density of the material was more high for the light than for those high energy particles :p
 





Thats exactly right.. you basically summed up what I said before but in a much coherent way.. thats impressive since english isnt even your native tongue!!

So does that mean what I said is correct? please correct me if I'm wrong.. its the only way to learn! -Adrian
 
No, basically you're right ..... when scentists says that they have "slowed down" the light, in reality they just found a medium with a group index so high, that the light can travel inside it only at that slow speed ..... but, ofcourse, when photons come out from that medium, they regain their original speed, cause a photon cannot, theorically, have a speed different that the one that is typical for the medium in which it travel (and yes, sorry for the bad English, i try to post clear, but sometimes made involuntary mistakes ..... or "grammatical massacres" :p)

For say that the light is slowed down, you need to find something that change its speed also after that the light have left the slowing medium and is come back in air (or void) ..... this is the dream of any laser-based weapon makers and laser research scentists ..... but til now, still a dream :D

About the reasons for which the photons are slowing their speeds in different mediums, there are different theories (but i don't know them good enough for explain them, sorry, i'm not a nuclear physic researcher ;)) ..... anyway, i remember one that, basically, say something like your idea, about the "more distance to do", and another was instead based on the "ambiguity" of the nature of the photons, that for those researchers, other than being without mass, are also simultaneously a wave and a particle (but here we enter in the "big headache equations" field ..... hell, i always hated Maxwell & co., at school :D)
 
i heard the term "optical path length" used before, does this have anything to do with the index of refraction and the slowing down of light???
 
Heres what I know of black holes... It is an implosion of the gravitational field of a calapsing/failing star. The Gravitational field becomes so strongly inverted that its powerful enough to bend even light. Many have speculated what is inside but today its believed to contain a solid core of condensed matter from whatever has been captured by its vacuum.
 
Holy crap, this thread is still alive!! haha

ROFL at the nerd war between HIMNL9 and dr-ebert !!!!!!!!!
 
Hey... has anyone hear heard anything about white holes? I think they correspond with dark matter, and dark flow and stuff such as that. I think most theories about white holes have been discounted though.

What heavenly mass could spit out matter at near light speed, while bending space- time in the opposite direction of a black hole?
 
Meatball said:
Hey... has anyone hear heard anything about white holes? I think they correspond with dark matter, and dark flow and stuff such as that. I think most theories about white holes have been discounted though.

What heavenly mass could spit out matter at near light speed, while bending space- time in the opposite direction of a black hole?
Click to expand...

Never heard of White Holes before so I looked it up. A few websites are throwing theories after theories at eachother. Yet they all say the same thing in the end... that being if one were to somehow be formed ... it would break apart almost instantly. I can imagine 1000 years into the future, everyone will be using blackhole/whitehole vacuum cleaners :crackup:
 
daguin said:
This is not really on topic, but I thought that some you might be interested . . . .

Steller Mystery Solved: Einstein Safe

SkyandTelescope.com - News Blog - Stellar Mystery Solved, Einstein Safe

Peace,
dave
Click to expand...

roddenberry said:
I remember reading about an interesting theory, mentioning that every single particle in the universe would have a limited lifespan, and that eventually, all matter in the universe would eventually cease to exist... I found something related to this right here:
Theory of Reciprocity - ENTITY: The Structure of a Fundamental Particle
as spock would say... fascinating!

Robert
Click to expand...

Daguin, the topic fits perfectly.

Roddenberry... thats scary stuff. Sometimes I feel that I would disappear if I thought to much my particles.

On a side note. Daguin, you were right about some members being "a bit volatile". But they have not gotten "over it" yet.
 
Meatball said:
Hey... has anyone hear heard anything about white holes? I think they correspond with dark matter, and dark flow and stuff such as that. I think most theories about white holes have been discounted though.

What heavenly mass could spit out matter at near light speed, while bending space- time in the opposite direction of a black hole?
Click to expand...


I thought the whole idea of white holes got rejected with the new theory of the virtual particles that Hawkins presented, because before the "white hole" was the other end of the black hole, like in another universe where everything that got sucked in here was dumped there. but since the black holes actually dissipate in this universe then there is no "other end"...
 
deam_87 said:
I thought the whole idea of white holes got rejected with the new theory of the virtual particles that Hawkins presented, because before the "white hole" was the other end of the black hole, like in another universe where everything that got sucked in here was dumped there. but since the black holes actually dissipate in this universe then there is no "other end"...
Click to expand...

Ah ok well I wasn't very sure about them myself. I was told in one of the classes the other day, that a couple of Einsteins equations suggested the possibility of their existence, but they did not require the existence of them. I just thought they were interesting to hear about.

Great article Dave!
 
There is a lot of crazy stuff out there. And I think lasers represent one step closer to the abilities to explore these things.
 
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