One of the physics geeks :)

Amazingly, scientists are becoming increasingly confident that they will be able to create black holes on demand, in quantity, using the new atom-smashers due to come online in the next five years. Some estimates suggest that the new Large Hadron Collider (LHC) at the European Center for Nuclear Research (CERN -the acronym is in French) will be able to create an average of one black hole each second. LHC will bombard protons and antiprotons together with such a force that the collision will create temperatures and energy densities not seen since the first trillionth of a second after the Big Bang. This should be enough to pop off numerous tiny black holes, with masses of just a few hundred protons. Black holes of this size will evaporate almost instantly, their existence detectable only by dying bursts of Hawking radiation.

Full article is here:
http://www.csmonitor.com/2003/0523/p25s02-stss.html

i cant help but think maybe creating blackhole isnt necessarily a good idea...

Read some books that deal with blackhole evaporation, i.e. Hawking Radiation.

Event Horizon, no :)

Lits, your answer is in the article down the bottom:

"But wait", I hear you say, "Has anyone considered that creating artificial black holes might not be the best idea?" The idea of creating black holes in the laboratory has to give one pause. I mean, how can anyone resist the urge to imagine future headlines like "Artificial Black Hole Escapes Laboratory, Eats Chicago" or some such thing? In reality, there is no risk posed by creating artificial black holes, at least not in the manner planned with the LHC. The black holes produced at CERN will be millions of times smaller than the nucleus of an atom; too small to swallow much of anything. And they'll only live for a tiny fraction of a second, too short a time to swallow anything around them even if they wanted to.

If it makes you feel any more comfortable, we're pretty sure that if the LHC can produce black holes, then so can cosmic rays, high-energy particles that smash into our atmosphere every day. There are probably a few tiny black holes forming and dying far above you right now. So I think we should all relax, fire up the Large Hadron Collider, and get ready for a view of the universe that we've never seen before.

In reality, there is no risk posed by creating artificial black holes, at least not in the manner planned with the LHC.

I wonder how many smoking pieces of land are still uninhabitable due to similar thinking by humans?!

This sort of uber-low-level physics is really fascinating; I did some googling last week on quantum physics and some of the theories and discoveries are really mindbogglingly interesting.

This sort of uber-low-level physics is really fascinating; I did some googling last week on quantum physics and some of the theories and discoveries are really mindbogglingly interesting.

Yep :) Can't wait for consumer verion of Quantum computer. I reckon they can do it within the next 10-20 years.

The thing that makes quantum physics what it is though is that it is so often out of our reach. The main consideration are the extremes, i.e hug densities and gravities or huge velocities. If these were EASILY acheivable, then they would have been realised long ao and called Classical/Newtoniam physics instead

i cant help but think maybe creating blackhole isnt necessarily a good idea...

Yeah i sort of thought that as well, but i read some of the comments in the slashdot thread, and they answered the questions like "wont it just get bigger and bigger"...
Well no, imagine making a black hole out of a matchbox.. the matchbox doesnt drag in surrounding matter, so making it a lot denser won't change that, and the electromagnetic forces at subatomic levels are much stronger than gravity, so it cant collide into other matter (it will be repelled) and "swallow" it, also its highly unlikely that it will collide with other matter.

Also i think the experiment can only succeeed if it already happens in nature, so as it is already happening everywhere, it shouldn't pose a danger in the lab.

I'll take one, it'd be awsome to make people dissapear with :D

but a blackhole does pull in extra matter and energy, otherwise it isn;t a black hole is it?
If it is drawing in more matter and energy, it will become denser, heavier, and the gravitational force will increase

A black hole only has as much gravity as it has matter.
Just because its a black hole, doesnt mean its gravity field is more than its mass would allow.

In reality, there is no risk posed by creating artificial black holes, at least not in the manner planned with the LHC.

I wonder how many smoking pieces of land are still uninhabitable due to similar thinking by humans?!

If you are talking about atomic weapons, then it might please you to note that it was mathmaticaly plausable for a atomic reaction to occure and to never stop. Destroying everything, from the test site, America, the Oceans, the world, the sun even the entire universe. They just didn't know what would happen when they dropped that bomb.

At least they think that this shouldn't destroy the existence, that is a major change.

Food for thought, I wonder how destructive Black Hole bombs are going to be.

Would they be able to use info gathered from these created blackholes to work out the speed of gravity?

The belief was that the heat would cause a reaction between hydrogen particles. This would in turn liberate enough energy to cause the same reaction on the next hydrogens, and make a chain reaction.
Rumor is, the professors who worked on the bombs took bets for how big the bang would be, and bunkers place at the respective positions to do recordings

does gravity have a velocity? I thought that a force by definition didn't have velocity

bah: How could the gravity be greater than the mass would allow anyhow? From what I know of phys with this, the thing that makes them what they are is the extreme density, so the gravitational attraction between very local particles and and the very dense area is very large due to the small radius allowed through that great. I don;t get argument for how that could be easily controlled

Interesting. Hmm instant black holes.. hmm.. Id be fascinated by seeing light being bent :)

How could the gravity be greater than the mass would allow anyhow?

It cant, thats why something that is very small being turned into a black hole won't swallow other things into it due to their gravity.

On a very small scale (subatomic) the repulsive forces between atoms are much greater than gravity, so they won't go towards each other.

And density has nothing to do with gravity, only mass does, even if a black hole wasnt so dense, it would still have the same gravity field, and be black.

bob: they would probably create it in a near vacuum with only what they wanted to use to create the black hole being in there.

If there is nothing for it to "suck in" and "grow" then what would be the harm?

If it is drawing in more matter and energy, it will become denser, heavier, and the gravitational force will increase

Do some reading before you try half arsed hypothesising :)

Black Holes dont become "denser". The density between a blackhole the size of a few atoms and a blackhole that may exist at the centre of this galaxy is absolutely identical. There are only three discernable characteristics that set one blackhole apart from another.

1.) Mass.
2.) Spin velocity (rotation rate).
3.) Electric charge.

Aside from these things, all blackholes are identical. Theres a saying among astrophysicists "A blackhole has no hair."

Also, a blackhole with the mass of a few atoms is going to affect surrounding matter virtually not at all. Gravity is the weakest of the universal forces, even though it can affect things over great distances.

Whats the practicle application for such an experiment? What do they hope to achive?

I reckon they just wanted to make a machine called an "atom smasher". God bless their tiny little hearts :)

One of my lecturers is doing stuff with gravitational fields and how they bend light.
He used to tell us how in theory their is a way to align micro black holes in a corkscrew shape and it will create this unknown region in the middle.
Its where the "tunnels" you see in movies and shows like sliders come from, some people have put forward stuff sayign that it could be used to get to speeds greater than light

Want to read an interesting book on this stuff, that comes as close to layman's terms as you can realistically expect? Very entertaining, too.

"The Five Ages of The Universe", by Adams and Laughlin (cant remember first names)

Though theres also "A Brief History of Time" by Stephen Hawking, less fun IMHO.

A thing: Stephen Hawking has a son called Timmy. Who, like me, reckons thats the influence for Timmy (Timmay!) from South Park? As far as I know the real Timmy doesn't have the same affliction as his father, but still.

I'll stop rambling now :)

bobbly bob: umm. correct me if I'm wrong. isn't gravity an acceleration? ie 9.8 m/s/s ?? I may be on the wrong track.

I'm not bobbly bob, but I'll correct you if you're wrong.

You're wrong.

9.8 metres per second per second is the rate of acceleration you can expect when you fall off a ladder here on earth. It varies according to the gravitational field you are in, as does the escape velocity (a big important thing for black holes).

And gravity is a force, not an acceleration, if anything could be said to be an acceleration anyway.

Will Gordon Freeman be working on any of this stuff?

here's a good blackhole FAQ that I just spent an interesting few minutes reading.

ta

StopShootingMe.
You seem more knowledgable in the physics than most of the people posting on the forums here. You might be able to help me with something.
When I was doing phys, I had a lecturer who was about to get a Phd from a way he had created to acheive a value for g-acceleration at different heights. What was exteremely strange about it to me, was that he was using geophysics. More specifically, he was looking at gravitational acceleration causing cleavage in particular crystals, and by analysing diffraction patterns with lasers I think, he was able to generate values for G.
You got any idea wtf is with that? I would have thought that the cleavage was too determine by stress lines and irregularities in large crystals, and too much on lattice energies with the smaller more defined crystals? How could something as weak as g have a strong enough effect?
Could it be change in diffraction patterns due to changing stress on the crystal at different G? Wouldn't the lattice energy stil be far too greater?

On a related topic did anyone see the recent National Geographic magazine which had the special on the creation of the universe etc? Very interesting reading... that sort of stuff blows me away.

http://magma.nationalgeographic.com/ngm/0302/feature1/index.html

bobbly bob sounds to me as though your lecturer was using Quantum Mechanics rather than relativity for his calculations. I know s***e all about Quantum Mechanics. Its why I changed my mind at the last moment and opted for Politics rather than Exploration Geophysics for university :) Otherwise I mght have heard this from your lecturer friend :)?

QM is wierd. Messed up. It introduced me to the notion of two-spin particles, or a name very like that. These are particles that are wierd. Say you take two playing cards (metaphor shamelessly stolen for Stephen Hawking), one represents a normal particle, the other a two-spin particle.

Now as we all know, playing cards bear the same motif whether you hold them one way up or the other (i.e. the Queen has two heads, but no arse) now if you take these two cards, lay them on the desk with queens up, and spin them around 360', the normal card (particle) will be the same way up as it began. The two-spin particle, however, will not. It will be, in effect, upside down. It has to be spun through 720' before its back where it started.

QM is messed up.

*EDIT*

Ooh, a way with Relativity instead of QM. This makes sense to me. One thing I can guess at: His crystals were found at different altitudes, yes? Thats what you were trying to say? Then the one found higher was in effect, younger than the one found at sea level or whatever altitude it was, regardless of whether they were formed at the same time. Time passed faster for the crystal stuck on the ground, and hence it would have weathered faster.

So by comparing how weathered they were, with the alititudes they were found at, with thier known ages, he could wotk out gravity at different heights. There :)

Another example I'll steal. Say a pair of identical twins (lets say, the Olsen Twins) share a bunk bed. Now, Mary-Kate has the top bed, while the other ugly one sleeps on the bottom. The distance apart is 1 metre. Over the course of a REALLY long time (years using scientific notation), thier ages will come to be very very different. Lemme see if I can find the figure. Its a difference of say, a few trillionths of a second per night. Ah, here we go, over 38 cosmological decades (the life of the Earth) the differential will be roughly 10^22 years.

So the moral of the story is, always bags the top bunk :) Or live on a hill :)

heh
yeah i remember something like that
i remember spins requiring complimentaries in other domains too. I got out of phys too though, mainly i realied there are no jobs in it unless u want to be a uni postgrad or lecturer

Heh, thats why im worried for choosing Politics :)

BTW ^ I edited.

I really wish that were it
What he was using was a lab made crystal, just the one, that he could use to measure g at different heights using different apparatus.
Im starting to think that even a change in surface pressure would be morely likely to cause an effect than a change in g with altitude....

I know :( The only thing I could think of was that somehow the lattice inside the crystal was REALLY well buffered from outside effects.

Hmm.

perhaps if the crystal was under focused stress with the change in gravity, maybe a particular point of the structure being pushed agains by a weight. If it were stressed, then there might be a change in scatter patterns with a laser...similar idea to causing a stress on metal and approximating g through change in electrical resistance

MSN ?

Boy, this really brought out the Physics buffs in the forum hasn't it :). Excellent and interesting discussions there.

Interesting. Hmm instant black holes.. hmm.. Id be fascinated by seeing light being bent :)

I rememebered some interesting discussion regarding how gravity or in this case black hole gravitational force affect light.

From memory light isn't suppose to have any mass due to the general theory of relativity law therefore gravity shouldn't affect it. Then how could a black hole bend or sucks the light in?

I heard someone said that because, light follows a _path_ in the space, and since a blackhole affect that space surrounding the area, light actually _follows_ that altered path . So basically the blackhole didn't pull light as such.

So I'm sure if I'm wrong Prof. StopShootingMe or Prof. Bah will correct me :)

P.S. there is an easier way of seeing light bent, and it involves substances ;) if you catch my drift :)

does gravity have a velocity? I thought that a force by definition didn't have velocity

What if something the size of the sun suddenly appeard in our solar system, how long would it take for its gravitational effects to be noticed? Wouldn't that be the speed of gravity? Is it instant?

light has a duality understanding; ot exhibits the prpoerties of both a particle and a wave of energy. There have been lots of experiments to prove the dual nature of light.
In so far as whether or not light can be bent by gravity, it is to my knowledge believed so. They are currently creating a testing facility in america which will shoot an extremely fine beam of light over 4km in a vaccuum tube to a sensor at the other end. They are hoping to find some kind of slight parabolic motion i think

The force would be here instantly. If you want to look at it in dimensions, the four forces are supposed to be external of the four dimensions that we visibly interact with. They are not so clearly bound together as to give an easy relationship such as m/s/s

I see, thats j0r!

light has a duality understanding; ot exhibits the prpoerties of both a particle and a wave of energy

That's what I was thinking too :) But if that's the case then wouldn't that violate the general law of relativity? Isn't the only way for any _thing_ to travel that the speed of light it _has_ be created at that state? Other wise you will never be able to speed up to it.

In any case it would be an interesting experiment.

What if something the size of the sun suddenly appeard in our solar system, how long would it take for its gravitational effects to be noticed? Wouldn't that be the speed of gravity? Is it instant?

Interesting question, I reckon the effect would be immediate as for its speed I don't know what you'd compare it to.

Well if it is in this other dimension place and its effects are instant it dosn't really have a speed. So that happily answers my question :D

energy and mass are interchangeable. This is where it gets ugly, and stopshootingme can prolly correct some of this, or all of it maybe, lol

Light is understood to atleast in part have properties pertaining to a particle moving in waves. In fact, a big part of quantum physics lies in the definition that all particles have wavelengths proportional to their mass and velocity, but on an everyday scale the amplitude is extremely small.
If we were to consider light to be a particle then, it must be one without mass, or atleast without a constant mass, or as you said, it would not be able to reach the speed of light. Instead, as it approached the speed of light, their would be an ever increasing amnount of momentum required, approaching an infinite value the closer you get to the speed of light.
I don't think that there is an extremely clear explanation of what light is in so far as the particle or pure energy argument. I had a lecturer once say that it makes perfect sense, just that we are brought up to think about it in comparison with everday circumstances and that makes it impossible to grasp.
Basically, we just have to leave it as light being made up of photons, small packets of defined amounts of energy, and these packets exhibit a duality in their nature

does gravity have a velocity? I thought that a force by definition didn't have velocity

-

What if something the size of the sun suddenly appeard in our solar system, how long would it take for its gravitational effects to be noticed? Wouldn't that be the speed of gravity? Is it instant?

The gravity wave travels at the speed of light.

If instead the sun just disappeared, it would take 8 minutes
for us to notice it on Earth. You would not only see the
sun disappear, but you would feel the violent gravitational
effect at the exact same instant.

They have yet to fully prove the existence of gravity
waves. Here is some info on a currently active detector.

The gravity-wave detector is pretty much a right-angle:

http://news.bbc.co.uk/media/images/38837000/jpg/_38837731_full_aerial_203_b.jpg

Edit: Just found this link for an earlier, different experiment.

As i understood it, the light itself isn't being bent but the space around the massive object is being curved by the gravity. Or something along those lines.

Also with bobbly_bobs thing about corkscrew black holes, could massive gravitational forces distort space to the point that quantum physics is represented a level much higher than normal? Cause that'd be wack.

Well most of the stuff you hear involving that tunnel, is based on hypothesizing what is at the other end.
Most of the reports get onto either time travel or parallel dimensions.
These kind of "micro" black holes though, are of about the mass of earth and similiar size to an atom, so they are kind of hard to make.
ineff is right too. relativity says that although gravity is not bound by the physical dimensions, and instead these dimensions are bound by it, there is a speed of propogation. This aint REALLY the speed of gravity, but the time for the force to be at an area, which is stil a property of gravity.
Still, though it is theoretically true that gravity propogates at the speed of light, the one major experiment used to prove it was so heavily refuted as innaccurate and nonsense that it hasn;t been used much since

Whats the practicle application for such an experiment? What do they hope to achive?

that's what they said about electricity research too :P

as for gravity, i was under the impression from various books i've read that it was instantanious, and doesn't have a "velocity". it merely extends a field, similar to a magnetic field. while comparitively the weakest of the 4 forces, it has the longest range of effect.

and the light mass and black hole question, i used to piss off my physics teacher with that one all the time. he couldn't answer it properly, and he'd just told me to go read up on it :P

Bah, I remember something about gravitons, and the fact that relativity doesnt explain why light has mass (which it does) but QMs can. But now I forget. Im not good at this stuff after I just woke up :(

Who can tell me more about Vacuum Energy? It sounds like fun, drawing on energy left over after Creation and all :) Its existence is yet to be proven (there was a series of experiments done, but nobody feels they are valid) but one group of scientists (and Dr. Carl too) suggested there would be enough of this "Vacuum Energy" occupying the 4 dimensional space inside your left sinus to vaporise evey ocean on Earth instantly :)

Fun.

This stuff sopunds like The Force or something. All around you, but not really there :)

trog don't even bring up quantum physics my teacher was trying to explain it to us and well lets just say WTF

he used and example that there is a cat in a box and poison gas is hooked up to it and there is an atom in another box but if you open the box with teh attom it may or may not be there the same as the cat is dead and not dead at the same time iam still confused from it

Whats the practicle application for such an experiment? What do they hope to achive?

It's obvious that the sole reason for creating such a destructive mass is to shoot the next generation of porn movies. The scene will start with some bloke and some chick standing at a bus stop, then it some how twists into them porking behind the dumpster around the back, then some dude with a black hole gun will jump out from behind the alley entrance just before the guy jizzes on her face, and shoots the jizz with the gun, causing some form of new finish to a facial.

I can see it now... Orgazmo 2 !!!

he used and example that there is a cat in a box and poison gas is hooked up to it and there is an atom in another box but if you open the box with teh attom it may or may not be there the same as the cat is dead and not dead at the same time iam still confused from it

Yeah! Schrödinger's Cat! I love it.

He (or you) have messed it up a bit but its a cool primer for the basics of QM.

Young Einstein (the Yahoo Serious movie) when he smashes the beer atoms to produce bubbles in larger, now that was a historic moment in physics. :)

Back on topic kind of, didn't tey use the principles that gravity effects (bends) light waves as a way of finding planets, they where able to determine that a star had celestrial bodies attached to it by the gravitaional effects their masses where having on the light waves being emited by the star.

EDIT: http://planetquest.jpl.nasa.gov/science/finding_planets.html

Gravitational Microlensing

http://planetquest.jpl.nasa.gov/images/gravitational_micro.jpg

This method derives from one of the insights of Einstein's theory of general relativity: gravity bends space. We normally think of light as traveling in a straight line, but light rays become bent when passing through space that is warped by the presence of a massive object such as a star. This effect has been proven by observations of the Sun's gravitational effect on starlight.

I think you're thinking of the scientists watching the stars and seeing the light disrupted by orbiting bodies passing between the star and us.

Ask dem0n. He seems to love astronomy stuff and will likely no what you're after.

Back on topic kind of, didn't tey use the principles that gravity effects (bends) light waves as a way of finding planets, they where able to determine that a star had celestrial bodies attached to it by the gravitaional effects their masses where having on the light waves being emited by the star.

They use that to find Black holes and some very very large stars. I don't think most stars will have enough gravitational force to actually bend light significantly for us to be able to detect it -- unless the star is huge. Especially when it's very far away.

If you read the Nature's article that bobbly_bob sent with experiment with Jupiter and its effect on a Quasar when they came close, the effect was alomost negligible it was pretty lucky that they could detect it at all -- with 20% margin of error so it's not conclusive proof just yet :). It's hard to say since Jupiter is very small in asronomical term.

The effects on light or other celestial bodies excert by Black holes on the other hand are relatively easier to detect due it its massive gravitational powah.

In any case it's the only way to _see_ Black holes i.e. by studying the surrounding area because light (or anything) can not escape from it once it crosses the event horizon.

Yeah you can "see" blackholes if they have a quasar surrounding them, or in a couple of cases because they are part of a binary star system (sort of) where they have a star orbiting around them (and being orbited by the blackhole in turn), often being slowly torn apart and swallowed. Poor little mite.

i saw that on discovery channel once

wewt! what a rockin' thread! :D More information than abuse!!... it's gotta be a QGL forum first ;]
Collapsed stars are awesome things to read about! There is just so much information yet to be discovered! The 2 books that StopShootingMe recommends are excellent for this sort of stuff! 'A Matter of Time' has cool theories about how black holes gather & lose energy.
Check this story from Hubble about a 'relatively' nearby "Stellar" class black hole that by mechanisms unknown blasted itself out of it's galactic orbit, grabbed its companion star for feul & shot off across the galactic plane!

Also very interesting are pulsars! Pulsars are neutron stars (collapsed stars with insufficient mass to become black holes) which have a companion star in orbit around them. The Velar Pulsar in the crab nebula is about the same mass as our sun but only about 20klms in diameter! & it spins ~10 times per second... now thats mind boggling! :]
http://imgsrc.hubblesite.org/hu/db/2002/24/images/a/formats/web.jpg

Also, here is some Gravitational Lensing stuff! orrjeh.

^^^ hehe I had that as my wallpaper a while back :) Still got it though, awesome pic.

Also demon smells.

Now it's officially a normal QGL thread. :D

I used to love having stellar maps like that as desktop wallpapers, then I found out they are false.
None of the mapping is done in visible light range for distant galaxies, and a lot now are being found theoretically through computer generation, then only "looked" at to check that the positions co-incide.
All of the really cool colours are used to map different regions, same as how they draw proteins in really pretty colours. It is a quick way to recognise the different key aspects.

Einstein actually fought pretty hard against the ideas of quantum physics, it being the wave of physics that came after his work was widely acclaimed. One of his favourite arguments was to say that quantum physicists suggested that our world is only in its current state because we are forever measuring it.He would use this to ask that if we were not looking at or in any way considering the moon, would it still be there?

What I would like to know is how there are different proofs for varying conditions within QM. I keep reading different examples, named after the different people that "discovered" them. I understand that we are flawed in our normal understanding of time as a linear prgression, but is instead a map of 10 dimensions whih are present in all states at all times. The difference, which we see is just our ever changing position within that map. What I would like to know then, is condisering that all states are present, how can various conditions arise? I appreciate that there are turbulences and changes caused by the interaction of the different dimensions, such as space-time turbulence etc. but how can these conditions be proven to be in a number of states? For example, it can be proven that our own local space time is in a number of states, the time and position no longer constant, and in theory allowing for infinite change amongst the conditions. This has been used to argue different ideas for time travel and time loops

A demon post with no animated gifs or glow text!

he used and example that there is a cat in a box and poison gas is hooked up to it and there is an atom in another box but if you open the box with teh attom it may or may not be there the same as the cat is dead and not dead at the same time iam still confused from it

I thought the theory was that before the box is opened the cat can be either alive or dead, 50/50 chance, and that until the box is opened the cat displays the properties of both states. Then when you open it you decide its fate, the roll of the QM dice doesn't happen till you open the box (observe it). Or something.

I think i may have been a couple of beers down when i hate it explained to me.

does gravity have a velocity? I thought that a force by definition didn't have velocity

there are theories that even forces are particles (and waves, the particle/wave duality of quantum physics), so i suppose they would have a velocity. according to the theory, it's really fast, faster than light or something... which is why black holes can suck light up. not sure how "accepted" the theory was, but i still read about it.

and i thought the definition of a black hole was a singularity that "swallowed" light, which is why it is called a "black hole", because light can't escape it therefore showing anything but "nothing"? if it's that small then it can't swallow light, and therefore by definition it wouldn't be a black hole... OR a singularity, because i thought a singularity had to have infinite gravity and mass (which has been disproven.. hasn't it?)..

I used to love having stellar maps like that as desktop wallpapers, then I found out they are false.

Most astronomical images of stuff that is outside our solar system are made by taking heaps of exposures in lots of different wavelengths of light & then make a composite image colourising the various wavelengths in different colours to represent the material that reflected/refracted the light. Does this make the image false!? Or is it the only way we could possibly represent it?
We have binocular vision evolved to resolve images at a very close range, a minute range in astronomical terms! When the different wavelengths of light attenuate over the vast distances of space our eyes have no way of recombining the spectrum so we more or less have to use a photographic process to be able to get even close to what the object might 'look' like in visible light even if such a thing were possible but it isnt! *gasp for breath* The concept of what nebulae & galaxies really 'look' like is inherantly flawed... up close they can be seen at all! because they are lots of very very very tiny particles that are a really really really big distance apart. A really long way away they can take on density & form but the colours are lost due to light frequency attenuation.

None of the mapping is done in visible light range for distant galaxies, and a lot now are being found theoretically through computer generation, then only "looked" at to check that the positions co-incide.

I have used a very cool 17.5" refractor telescope that can resolve many of the famous astronomical sights... like the eagle nebula & the horsehead nebula... they look pretty much as they do in the hubble/ESO/NOAJ pics but in grey scales. Personally I like the colourised images that the science institutes provide!! They are preeeettty :D

AsifGlowtextDuzznRoxJ00!

http://dem0n.qgl.org/images/mgifz/gsq2.gif

and i thought the definition of a black hole was a singularity that "swallowed" light, which is why it is called a "black hole", because light can't escape it therefore showing anything but "nothing"? if it's that small then it can't swallow light...

Sorry, could you clarify this a little? Do you mean the by-products of this project (the atom-sized blackholes) couldn't be real blackholes, or are we talking about something else now? :)

Confused.

I thought the theory was that before the box is opened the cat can be either alive or dead, 50/50 chance, and that until the box is opened the cat displays the properties of both states. Then when you open it you decide its fate, the roll of the QM dice doesn't happen till you open the box (observe it).

Its more a comparison to show how quantum theory is applied in an observable situation, and how weird it is when used on observable objects.

I bet if you ever reach total enlightenment, beer would shoot out of your nose

Sorry, could you clarify this a little? Do you mean the by-products of this project (the atom-sized blackholes) couldn't be real blackholes, or are we talking about something else now? :)

i suppose i'm being pedantic... i'm saying that i thought they wouldn't be called black holes because they wouldn't be black, or more to the point, they couldn't be seen except in comparison to everything else. black holes are "black" because light cannot escape them, but these black holes won't swallow light, they're too small and powerless...

it's ok, they're called black holes anyway i think, because i think that's the name generally accepted for the phenomena now, instead of being a name for something we cannot "see" (receive light from). if that doesn't make sense, don't worry. :D

Singularity caused by infinite density. Im pretty sure that was the original condition, though now there are all kinds of suggested modifications

edit: something I just thought of that is really f***ing with my head: Time is not a linear line, it is an infinte realm, within which we are travelling along in a straight line. i.e, it is our path that is straight, not time itself. Does that mean that all of our "space" is being occupied by an infinte number of possibilities at infinite different positions on that map of time travelling along their own path?

Bobbly_bob read up on string theory it might help answer, or confuse you more,a good place to start is..

http://superstringtheory.com/

Toll if you're up on String Theory can you tell me a little about Calabi-Yau shapes? They confuse the s*** out of me :( Cant even really tell what they're (i.e. the scientists) on about.

Maybe I just read poorly worded essays, or maybe its just beyond me :)

Yeah, heh, maybe you can help me out too. From what I can remember studying string theory, and reading that link you gave and a few others.... I aint anywhere near something like an answer

Yer I've only just starting reading about string theories and I've come to the conclusion that I wont really be able to understand it without studing the maths behind it... and there is alot.

Just in laymens terms it is hard enough to get a grip of, but I'll keep plugging away at it cause it is really interesting stuff.

One of the bits I find really bizar is how with one theory there are 11 dimensions and with another there are 10, and if you do a few twists and turns you can make one theory the other (as I understand it, well partially understand.. I think.. :D ).

bobbly_bob:

as the past will show, things are usually classified as infinite when we don't know enough about them... the universe is one such example. while there is no definite answer still, it is generall accepted that the universe in fact does not infintely stretch, but is in fact accelerating outwards, but the space it takes up is limited. black holes were originally called singularities for some reason i have forgotten, but they were meant to have infinite density/mass/gravity all that... and now it seems they don't. they can actually die, it just takes a long time for them to do so (depending of course on size and mass).

also, i have little idea as to how valid my line of thought is, but to me space involves three dimensions, first second and third, xyz i'm sure we're all familiar with that... and time is the fourth, and i've decided reality is the fifth. time is like the x axis and reality is the y. however, that is a conclusion based on little mathematics (NO mathematics). meh. the more we know, the more we don't know.

string theory sounds interesting, i'm gonna bookmark that site, thanks toll ;)

druid, "reality" is best left to philosphers, rather than science :)

As to the number of dimensions, try string theory, as above :)

Yeah, first four are right. Its believed though that our "world" was created by a disturbance in the equilibrium between the 10 dimensions. The result was the collapse of the later 6 into something infinitely small, causing the 4 dimensions to be predominant. Mathematically, it is possible to prove that the other 6 dimensions cause the 4 forces, but not by me of course, heh.
If you want to mix physics with philosophy, I used to have a Physics teacher who believed in a God. His reason was that if you have 10 dimensions, in perfect equilibrium, what could possibly disturb that equilibrium?? In order to affect them, and cause the collapse and creation of our universe, you must have some "body" that is OUTSIDE of all known dimensions. i.e, can not be bound by time, length, width, bredth, gravity, nuclear or electromagnetic forces, as these are not yet seperate or defined. He believed that "God" was that force that was able to shape the 10 dimesions that we are bound within.. pretty hard case to argue against

If we were to consider light to be a particle then, it must be one without mass, or atleast without a constant mass, or as you said, it would not be able to reach the speed of light. Instead, as it approached the speed of light, their would be an ever increasing amnount of momentum required, approaching an infinite value the closer you get to the speed of light.

Here's a different way of looking at special relativity:

Einstien built his model from one critical fundametal, that the OBSERVED speed of light is the same from each observer. This means that if you're speeding past in your spaceship a 2*10^8 m/s or sitting in front of your computer, you should be able to observe light from all directions reaching you at the same speed. The critical difference is that regardless of your ACTUAL speed, the OBSERVED speed of light is always the same.

For this to occur, you need to throw out other constants, such as time. As you approach an actual speed of 3*10^8 m/s, your time dilates so that other people observing your speed see you travelling slower than light (since a second to them is measured differently to a second for you). You can speed up to 7*10^8m/s if you like, but you'd still see light coming at you from all directions at an observed speed of 3*10^8, and others will still observe you going closer and closer to their observed speed of light, but not faster than it.

So how does this help us understand the difference between mass and energy? Well, consider that no matter what speed you actually go, you can still measure light going 'faster', what is the actual speed of light ? It's obviously infinite, or at least unmeasurable because it would take light (or any other released energy) 0 time to reach it's destination ACCORDING TO ITSELF. So when an electron drops from one state to another and releases a burst of energy, that burst immediately affects another particle somewhere else in our observable universe, but we OBSERVE that event at a constant time afterward, namely at 'the speed of light'.

Sound broken? well, it's our understanding of time that is broken, not energy istelf. When we observe an event we expect to do so within a reference of time, but energy in motion does not exist in time at all. So something with mass is essentially energy in a rest state that is observable, whereas energy in its released state is not observable (the effects of its arrival into mass at another point are once again observable). Can something with mass go the speed of light? no, because mass by this definition needs to remain observable, and observable objects always can observe light going faster. It doesn't need to though, as it can be 'transferred' to another point at the speed of light by converting mass back to energy via E=mc^2.

Quantum Mechanics essentially starts off by trying to figure out what happens when there is no 'observer'.

Black holes are a wierd mix of these 2 elements. The event horizon really defines the border of observable space, not the fact that light cannot escape. If light itself takes no time to reach another point, what stops it escaping a black hole? Well, it can, but the universe will end in our timeframe before we actually get to observe it. What happens when it gets there is anybody's guess.

i'm not used to this... i feel strangely left behind in all this now :P

I'm not sure that is quite right... We were shown demonstrations for relivity that showed as you approcah the speed of light, you in fact can no longer receive light from all sides.
If you want an example of the videos we were shown in lectures, try the link below. The highway video gives the best example.
highway demo

I'm not sure that is quite right... We were shown demonstrations for relivity that showed as you approcah the speed of light, you in fact can no longer receive light from all sides.

Yes, you do still receive light, or more accurately, electromagnetic radiation from each direction. What those experiments show is that light is redshifted perpendicular to your velocity, so much so when you get close to the speed of light that you are moving it out of the visible spectrum down into infra-red or lower frequencies. The point to remember is that frequency has a time component, but time is stretched from your point of view.

The aberration of light is a little different. Aberration makes observed light coming from the side to 'appear' like it is coming more from the front. Well actually for the viewer it does come from the front, but that still doesn't stop other light from further behind the direction of travel being skewed into a side on position. All it means is that the intensity of light is focused more toward your forward direction.

When actually sitting in the car and attempting to determine the speed of light hitting you or being emitted from you, you will still find that it remains a constant, but your mind will prolly be more interested in the warping effects going on around you ;)

If you're interested, google up some Michelson-Morley experiments to see the work done on the constant speed of light independant of velocity. It was pretty crucial to the development of special relativity.