Dark Matter..

[FatDave]

A lot of scientists say that it matters, because its the final element with, which they will be able to completely unravel the mystery how did we come to be, am talking about the big bang (not the movie). That is the reason why The Large Hadron Collider exists, scientists want to recreate the big bang to see how it really happened. The biggest speculation, going around LHC, is that when they start the reacting of the big bang the LHC will also create a black whole. Shorty meaning that we will all be consumed in time.

Simply put, for the sake of understanding everything we do it matters. Scientists believe that Dark Matter is the final key element, which will help speed up our technological and scientific progress.

 

Sorry mate, but way off the mark.

 

Anything held in gravitational pull is actually falling. The moon is falling towards earth at the same speed (or very slightly slower as the moon is moving away from the Earth) as it is moving sideways, so it appears that it is just circling the earth. The closer an object to the mass it is orbiting, the faster it needs to move in a sideways direction to avoid falling in to the boject it is orbiting. So, if the moon were twice as far away, it would need to travel much slower to stay in orbit, otherwise it would fly away from the earth, out of the earths gravitational grip.

 

When we began to observe galaxies some years back we expected to see the same rules at work; the stars closest to the supermassive black holes at their center moving incredibly fast and the stars at the edge of the galaxies moving much slower. Instead we actually found that all the stars inside each galaxy are orbiting at the same speed, which means that the ones on the outside arms should have broken free and be flying through space independent of the galaxy it belonged to. The only possible explination is that there is mmatter unnacounted for, therefore creating this extra gravity. This is Dark Matter.

 

Dark Energy is something different.

When the Universe originaly "banged" 13.7 billion years back a lot of expansion happened in a short time, faster than the "imutable" speed of light for a short time.

After 13.7 billion years, we measured the speeds of the nearby and distant galaxies and found that not only are they not slowing down, they are actually still increasing in speed. The universe is expanding and getting faster. This means that the Big Bang is still Banging. Physasists have no idea what the energy fueling this expansion is, so they just stick the word Dark infront of it which means "will explain later".

 

As far as the Large Hadron Collider goes and the black holes, this is simply the press gone nuts. Yes black holes are created, but they are made by the extreme gravity created when particles collide. Because of Hawkin's Radiation - don't get me started on that faker either - which tells us that black holes "evaporate" over billions of years, the bigger they are, the longer they take, therefore micro black holes dissapear almost the instant they are created.

A "normal" black hole is made up of billions of tons of matter, all compressed by it's own gravity into a tiny space. If the earth were to become a black hole then all it's matter would have to be compressed to less than a centremeter in diabeter. The black holes formed in the LHC are made up of two partacle of lead. They pose no danger to us whatsoever.

[0742Sheff]

Nice post Dave

[mym8scallmeh]

Well I am completely in the dark now so guess it doesnt matter

[quisquose]

On last week's Infinite Monkey Cage Billy Bragg made a right tit of himself when he complained that dark energy/matter was a faith, or belief based idea, that scientists were asking us to believe in, same as religion basically.

 

Tony Ryan ( ) neatly replied that the discrepancy between the theory and the observation meant that either we need to find a better theory, which is happening, or we need to find the missing matter, which is happening. So the total opposite of a faith basically.

[RootsBooster]

Sorry mate, but way off the mark.

 

Anything held in gravitational pull is actually falling. The moon is falling towards earth at the same speed (or very slightly slower as the moon is moving away from the Earth) as it is moving sideways

 

Is it just me or does this contradict itself?

[evildrneil]

It's aether sneaking in through the back door!

[alchresearch]

Near here there is a laboratory for researching dark matter so thought we could discuss dark matter, anybody found any?

 

I've been to it, the place is amazing! If you can get yourself on a trip do it!

 

Just make sure you take plenty of water, you'll go through at least 4 litres.

[Alcoblog]

Is it just me or does this contradict itself?

 

I think I read about this somewhere. The Moon would very much like to fall to earth (gravity), but due to its speed (centrigugal force?) it wants to pull away at the same time.

It's a bit of a coincidence that the two forces pretty much cancel each other out, although I think gravity's winning by a few feet per year. (I may be wrong!)

[RootsBooster]

I think I read about this somewhere. The Moon would very much like to fall to earth (gravity), but due to its speed (centrigugal force?) it wants to pull away at the same time.

It's a bit of a coincidence that the two forces pretty much cancel each other out, although I think gravity's winning by a few feet per year. (I may be wrong!)

 

Ah so he probably just worded it wrong?

 

(also, I think it's actually moving gradually away from us, isn't that what they discovered when they were shooting the big green laser at it?)

[Obelix]

Is it just me or does this contradict itself?

 

Not really you just have to look at how the Moon falls.

 

The Moon falls towards the Earth at freefall speed, which is counteracted by the Moon revolving about the Earth at just the right speed so it stays in orbit. This is an orbit as I'm sure is clear to everyone.

 

However - the wrinkle in this is that the Earth is also rotating. (The moon is tidally locked to point at the Earth so it doesnt rotate as far as the Earth is concerned.)

 

This rotation of the Earth is angular momentum and it's slowing down due to friction of the oceans on the seabed, the inner core, etc. As a result of this slowdown the Moon ends up increasing it's distance from the Earth - about 4cm a year I think is the current figure. Hence the reference to it not boing quite as fast - it moves out about 3.8mm per orbit.