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Ok so here goes. For starters let me say I am not an expert on Quantum Physics by an means, but I will try to post material that will be fun to learn and understand!

Lets start with one of my favorite subjects M-THEORY! woot

INTRO:
In physics, M-theory (sometimes also called U-theory) is a proposed "master theory" that unifies the five superstring theories. and used M-theory is used to explain a number of previously observed dualities, sparking a flurry of new research in string theory called the second superstring revolution.

In the early 1990s, it was shown that the various superstring theories were related by dualities, which allow physicists to relate the description of an object in one string theory to the description of a different object in another theory. These relationships imply that each of the string theories is a different aspect of a single underlying theory, proposed by Witten, and named "M-theory".

M-theory is not yet complete; however it can be applied in many situations (usually by exploiting string theoretic dualities). It was suggested that a general formulation of M-theory will probably require the development of a new mathematical language. However, some scientists have questioned the tangible successes of M-theory given its current incompleteness, and limited predictive power, even after so many years of intense research.

MEMBRANES:
Prior to M-theory, strings were thought to be the single fundamental constituent of the universe, according to string theory. When M-theory unified the five superstring theories, another fundamental ingredient was added to the makeup of the universe - membranes. Like the tenth spatial dimension, the approximate equations in the original five superstring models proved too weak to reveal membranes. A membrane, or brane, is a multidimensional object, usually called a p-brane, with p referring to the number of dimensions in which it exists. The value of 'p' can range from zero to nine, thus giving branes dimensions from zero (0-brane ≡ point particle) to nine - five more than the world we are accustomed to inhabiting (3 spatial and 1 time).

The inclusion of p-branes does not render previous work in string theory wrong on account of not taking note of these p-branes. P-branes are much more massive ("heavier") than strings, and when all higher dimensional p-branes are much more massive than strings, they can be ignored, as researchers had done unknowingly in the 1970s.

Shortly after Witten's( quantum physisists) breakthrough in 1995, Joseph Polchinski of the University of California, Santa Barbara discovered a fairly obscure feature of string theory. He found that in certain situations the endpoints of strings (strings with "loose ends") would not be able to move with complete freedom as they were attached, or stuck within certain regions of space. Polchinski then reasoned that if the endpoints of open strings are restricted to move within some p-dimensional region of space, then that region of space must be occupied by a p-brane. These type of "sticky" branes are called Dirichlet-p-branes, or D-p-branes. His calculations showed that the newly discovered D-p-branes had exactly the right properties to be the objects that exert a tight grip on the open string endpoints, thus holding down these strings within the p-dimensional region of space they fill.

Not all strings are confined to p-branes. Strings with closed loops, like the graviton, are completely free to move from membrane to membrane. Of the four force carrier particles, the graviton is unique in this way. Researchers speculate that this is the reason why investigation through the weak force, the strong force, and the electromagnetic force have not hinted at the possibility of extra dimensions. These force carrier particles are strings with endpoints that confine them to their p-branes. Further testing is needed in order to show that extra spatial dimensions indeed exist through experimentation with gravity.


^.^ I'll leave it at this for a bit. Let it sink in. Next will be worm hole theory and black holes.

Woa... too much 411. Brain hurts.

You know I have a theory of my own. I believe that physicists intentionally made these "theories" as hard to understand as possible so people like me who are incapable of understanding them are forced to believe them.

Hershey wrote::? i bit too many advanced words for me >< lol very interesting though


cant wait for that black holes theory..^^

Ya ill be posting those right now:

Black Holes (2nd fav QP topic)

INTRO To BH's:
A black hole is an object with a gravitational field so powerful that a region of space becomes cut off from the rest of the universe – no matter or radiation, including visible light, that has entered the region can ever escape. The lack of escaping electromagnetic radiation renders the inside of black holes (beyond the event horizon) invisible, hence the name. However, black holes can be detectable if they interact with matter, e.g. by sucking in gas from an orbiting star. The gas spirals inward, heating up to very high temperatures and emitting large amounts of light, X-rays and Gamma rays in the process while still outside of the event horizon. Black holes are also thought to emit a weak form of thermal energy called Hawking radiation.

While the idea of an object with gravity strong enough to prevent light from escaping was proposed in the 18th century, black holes as presently understood are described by Einstein's theory of general relativity, developed in 1916. This theory predicts that when a large enough amount of mass is present within a sufficiently small region of space, all paths through space are warped inwards towards the center of the volume. When an object is compressed enough for this to occur, collapse is unavoidable (it would take infinite strength to resist collapsing into a black hole). When an object passes within the event horizon at the boundary of the black hole, it is lost forever (it would take an infinite amount of effort for an object to climb out from inside the hole). Although the object would be reduced to a singularity, the information it carries is not lost (see the black hole information paradox).

While general relativity describes a black hole as a region of empty space with a pointlike singularity at the center and an event horizon at the outer edge, the description changes when the effects of quantum mechanics are taken into account. The final, correct description of black holes, requiring a theory of quantum gravity, is unknown.

BLACK HOLES!

Event horizon
This is the boundary of the region from which not even light can escape. An observer at a safe distance would see a dull black sphere if the black hole was in a pure vacuum but in front of a light background such as a bright nebula. The event horizon is not a solid surface, and does not obstruct or slow down matter or radiation which is traveling towards the region within the event horizon.

The event horizon is the defining feature of a black hole - it is black because no light or other radiation can escape from inside it. So the event horizon hides whatever happens inside it and we can only calculate what happens by using the best theory available, which at present is general relativity.

The gravitational field outside the event horizon is identical to the field produced by any other spherically symmetric object of the same mass. The popular conception of black holes as "sucking" things in is false: objects can maintain an orbit around black holes indefinitely provided they stay outside the photon sphere (described below).

Singularity at a single point
According to general relativity, a black hole's mass is entirely compressed into a region with zero volume, which means its density and gravitational pull are infinite, and so is the curvature of space-time which it causes. These infinite values cause most physical equations, including those of general relativity, to stop working at the center of a black hole. So physicists call the zero-volume, infinitely dense region at the center of a black hole a "singularity".

The singularity in a non-rotating, uncharged black hole is a point, in other words it has zero length, width and height.

But there is an important uncertainty about this description: quantum mechanics is as well-supported by mathematics and experimental evidence as general relativity, and does not allow objects to have zero size - so quantum mechanics says the center of a black hole is not a singularity but just a very large mass compressed into the smallest possible volume. At present we have no well-established theory which combines quantum mechanics and general relativity; and the most promising candidate, string theory, also does not allow objects to have zero size.

The rest of this article will follow the predictions of general relativity, because quantum mechanics deals with very small-scale (sub-atomic) phenomena and general relativity is the best theory we have at present for explaining large-scale phenomena such as the behavior of masses similar to or larger than stars.

A photon sphere
A non-rotating black hole's photon sphere is a spherical boundary of zero thickness such that photons moving along tangents to the sphere will be trapped in a circular orbit. For non-rotating black holes, the photon sphere has a radius 1.5 times larger than the radius of the event horizon. No photon is likely to stay in this orbit for long, for two reasons. First, it is likely to interact with any infalling matter in the vicinity (being absorbed or scattered). Second, the orbit is dynamically unstable; small deviations from a perfectly circular path will grow into larger deviations very quickly, causing the photon to either escape or fall into the hole.

Other extremely compact objects such as neutron stars can also have photon spheres. This follows from the fact that light "captured" by a photon sphere does not pass within the radius that would form the event horizon if the object were a black hole of the same mass, and therefore its behavior does not depend on the presence of an event horizon.

Accretion disk
Space is not a pure vacuum - even interstellar space contains a few atoms of hydrogen per cubic centimeter. The powerful gravity field of a black hole pulls this towards and then into the black hole. The gas nearest the event horizon forms a disk and, at this short range, the black hole's gravity is strong enough to compress the gas to a relatively high density. The pressure, friction and other mechanisms within the disk generate enormous energy - in fact they convert matter to energy more efficiently than the nuclear fusion processes that power stars. As a result, the disk glows very brightly, although disks around black holes radiate mainly X-rays rather than visible light.

Accretion disks are not proof of the presence of black holes, because other massive, ultra-dense objects such as neutron stars and white dwarfs cause accretion disks to form and to behave in the same ways as those around black holes.

OH NOES IM FALLING INTO A BH SECTION

Spaghettification
An object in any very strong gravitational field feels a tidal force stretching it in the direction of the object generating the gravitational field. This is because the inverse square law causes nearer parts of the stretched object to feel a stronger attraction than farther parts. Near black holes, the tidal force is expected to be strong enough to deform any object falling into it; this is called spaghettification.

The strength of the tidal force depends on how gravitational attraction changes with distance, rather than on the absolute force being felt. This means that small black holes cause spaghettification while infalling objects are still outside their event horizons, whereas objects falling into large, supermassive black holes may not be deformed or otherwise feel excessively large forces before passing the event horizon.

Before the falling object crosses the event horizon
An object in a gravitational field experiences a slowing down of time, called gravitational time dilation, relative to observers outside the field. The observer will see that physical processes in the object, including clocks, appear to run slowly. As a test object approaches the event horizon, its gravitational time dilation (as measured by an observer far from the hole) would approach infinity.

From the viewpoint of a distant observer, an object falling into a black hole appears to slow down, approaching but never quite reaching the event horizon: and it appears to become redder and dimmer, because of the extreme gravitational red shift caused by the gravity of the black hole. Eventually, the falling object becomes so dim that it can no longer be seen, at a point just before it reaches the event horizon. All of this is a consequence of time dilation: the object's movement is one of the processes that appear to run slower and slower, and the time dilation effect is more significant than the acceleration due to gravity; the frequency of light from the object appears to decrease, making it look redder, because the light appears to complete fewer cycles per "tick" of the observer's clock; lower-frequency light has less energy and therefore appears dimmer.

From the viewpoint of the falling object, distant objects may appear either blue-shifted or red-shifted, depending on the falling object's trajectory. Light is blue-shifted by the gravity of the black hole, but is red-shifted by the velocity of the infalling object.

As the object passes through the event horizon
From the viewpoint of the falling object, nothing particularly special happens at the event horizon (apart from spaghettification due to tidal forces, if the black hole has relatively low mass). A falling observer would measure a non-infinite amount of time (in their reference frame) needed to fall past the point where the event horizon is supposed to be.

An outside observer, however, will never see an infalling object cross this line. The object appears to halt just above the horizon, due to gravitational time dilation, fading from view as its light is red-shifted and the rate at which it emits photons drops to approach zero. This doesn't mean that the object never crosses the horizon; instead, it means that light from the horizon-crossing event is delayed by a time that approaches infinity as the object approaches the horizon. The time of crossing depends on how the outside observer chooses to define space and time axes on spacetime near the horizon.

In practice, additional effects are expected to occur as an object approaches the event horizon of a black hole. Hawking radiation is expected to grow brighter, approaching the Planck temperature as an infalling object approaches to within the Planck length of the horizon. Both relativistic and quantum mechanical effects may present a backwards pressure that approaches infinite strength near the horizon, making the fate of infalling objects unclear. This type of back-pressure may cause the region near or within the event horizon to be at very high temperature. As of 2007, there is no scientific consensus about what happens as objects fall into black holes, beyond the fact that it's expected to differ from the picture described by general relativity.

Inside the event horizon
The object reaches the singularity at the center within a finite amount of proper time, as measured by the falling object. An observer on the falling object would continue to see objects outside the event horizon, blue-shifted or red-shifted depending on the falling object's trajectory. Objects closer to the singularity aren't seen, as all paths light could take from objects farther in point inwards towards the singularity.

The amount of proper time a faller experiences below the event horizon depends upon where they started from rest, with the maximum being for someone who starts from rest at the event horizon. A study in 2007 examined the effect of firing a rocket pack with the black hole, showing that this can only reduce the proper time of a person who starts from rest at the event horizon. However, for anyone else, a judical burst of the rocket can extend the life time of the faller, but over doing it will again reduce the proper time experienced. However, this cannot prevent the inevitable collision with the central singularity.

Hitting the singularity
As a infalling object approaches the singularity, tidal forces acting on it approach infinity. All components of the object, including atoms and subatomic particles, are torn away from each other before striking the singularity. At the singularity itself, effects are unknown; a theory of quantum gravity is needed to accurately describe events near it. Regardless, as soon as an object passes within the hole's event horizon, it is lost to the outside world. An observer far from the hole simply sees the hole's mass, charge, and angular momentum change to reflect the addition of the new object's matter.

ENJOY! Worm holes to come next.

Oh.. My god..

Black hole formulas

Black holes are predictions of Albert Einstein's theory of general relativity. There are many known solutions to the Einstein field equations which describe black holes, and they are also thought to be an inevitable part of the evolution of any star of a certain size. In particular, they occur in the Schwarzschild metric, one of the earliest and simplest solutions to Einstein's equations, found by Karl Schwarzschild in 1915. This solution describes the curvature of spacetime in the vicinity of a static and spherically symmetric object, where the metric is,

ds²= -c²(1 - 2Gm/c²r) dt² + (1 - 2Gm/ c²r)­‾­­¹ dr² + r²dΩ²

where dΩ² = dΘ² + sin²ΘdΦ² is a standard element of solid angle.

According to general relativity, a gravitating object will collapse into a black hole if its radius is smaller than a characteristic distance, known as the Schwarzschild radius. (Indeed, Buchdahl's theorem in general relativity shows that in the case of a perfect fluid model of a compact object, the true lower limit is somewhat larger than the Schwarzschild radius.) Below this radius, spacetime is so strongly curved that any light ray emitted in this region, regardless of the direction in which it is emitted, will travel towards the centre of the system. Because relativity forbids anything from traveling faster than light, anything below the Schwarzschild radius – including the constituent particles of the gravitating object – will collapse into the centre. A gravitational singularity, a region of theoretically infinite density, forms at this point. Because not even light can escape from within the Schwarzschild radius, a classical black hole would truly appear black.

The Schwarzschild radius is given by rs = 2Gm/ c²
where G is the gravitational constant, m is the mass of the object, and c is the speed of light. For an object with the mass of the Earth, the Schwarzschild radius is a mere 9 millimeters — about the size of a marble.

The mean density inside the Schwarzschild radius decreases as the mass of the black hole increases, so while an earth-mass black hole would have a density of 2 × 1030 kg/m3, a supermassive black hole of 109 solar masses has a density of around 20 kg/m3, less than water! The mean density is given by
ρ = 3c^6/ 32πm²G³ (that 6 should be a superscript but I forgot how to do it)

Since the Earth has a mean radius of 6371 km, its volume would have to be reduced 4 × 1026 times to collapse into a black hole. For an object with the mass of the Sun, the Schwarzschild radius is approximately 3 km, much smaller than the Sun's current radius of about 696,000 km. It is also significantly smaller than the radius to which the Sun will ultimately shrink after exhausting its nuclear fuel, which is several thousand kilometers. More massive stars can collapse into black holes at the end of their lifetimes.

The formula also implies that any object with a given mean density is a black hole if its radius is large enough. The same formula applies for white holes as well. For example, if the observable universe has a mean density equal to the critical density, then it is a white hole, since its singularity is in the past and not in the future as should be for a black hole.

More general black holes are also predicted by other solutions to Einstein's equations, such as the Kerr metric for a rotating black hole, which possesses a ring singularity. Then we have the Reissner-Nordström metric for charged black holes. Last the Kerr-Newman metric is for the case of a charged and rotating black hole.

There is also the Black Hole Entropy formula: S = Akc³/4ħG
Where A is the area of the event horizon of the black hole, ħ is Dirac's constant (the "reduced Planck constant"), k is the Boltzmann constant, G is the gravitational constant, c is the speed of light and S is the entropy.

A convenient length scale to measure black hole processes is the "gravitational radius", which is equal to rG= Gm/c²

When expressed in terms of this length scale, many phenomena appear at integer radii. For example, the radius of a Schwarzschild black hole is two gravitational radii and the radius of a maximally rotating Kerr black hole is one gravitational radius. The location of the light circularization radius around a Schwarzschild black hole (where light may orbit the hole in an unstable circular orbit) is 3rG. The location of the marginally stable orbit, thought to be close to the inner edge of an accretion disk, is at 6rG for a Schwarzschild black hole.

Enjoy!

oh shit much to read LOL later hmm some strange blabla ρ = 3c^6/ 32πm²G³

BlackFox wrote:oh shit much to read LOL later hmm some strange blabla ρ = 3c^6/ 32πm²G³

the p and the weird n should be both greek letters, the n should have come out as the Pi symbol the p should be a small letter Rho. the ^6 means super script 6 as in to the 6th power. I forgot how to do the alt key for super script 6 so I left it like that XD

PureOwnage wrote:

BlackFox wrote:oh shit much to read LOL later hmm some strange blabla ρ = 3c^6/ 32πm²G³

the p and the weird n should be both greek letters, the n should have come out as the Pi symbol the p should be a small letter Rho. the ^6 means super script 6 as in to the 6th power. I forgot how to do the alt key for super script 6 so I left it like that XD

ok...

Spaghettification, now thats what im talking about

Woot! I got some readers (makes me feel good XD) As far as worm holes go I might save that post for tomarrow. I want to let all the material I posted some time to set in.

Nice I have somethin interesting and hard to understand to take my time up cos it's so god damn slow at work today.

With this knowledge and my ability to solve the rubik's cube, no one can doubt my intelligence now.

LOL

j/k kidding. I like the materials. Keep posting.

Anh_Hung_Rom wrote:With this knowledge and my ability to solve the rubik's cube, no one can doubt my intelligence now.

LOL

j/k kidding. I like the materials. Keep posting.

will do

I LOVE SPACE *reads*

this and organic chemistry

QUARKS! QUARKS! QUARKS! QUARKS!

find the missing quark and we rule the universe!!! muahahhaha

well no we wouldnt, but its just as big for physics researchers

Wow, right when I happen to be reading books on string theory, general relativity, and quantum mechanics...nice post

We should have a School/Education section in the forums! It would be of great use! and the first stickey should be Homework Help!

CrimsonNuker wrote:We should have a School/Education section in the forums! It would be of great use! and the first stickey should be Homework Help!

yes... i need help with my essay.... heres what I got so far

" The..."

so what do u think?

more like do homework for me

shadowman20875 wrote:

CrimsonNuker wrote:We should have a School/Education section in the forums! It would be of great use! and the first stickey should be Homework Help!

yes... i need help with my essay.... heres what I got so far

" The..."

so what do u think?

more like do homework for me

now put in the story from the 3 word story thread lmao

OMG WIKIPEDIA!!!

Didnt read any of it.
Old.
Outdated.
Whatever you call it, quantum mechanics was yesterdays game.
Time to play String theory.

shadowman20875 wrote:this and organic chemistry

QUARKS! QUARKS! QUARKS! QUARKS!

find the missing quark and we rule the universe!!! muahahhaha

well no we wouldnt, but its just as big for physics researchers

How can one not love organic chem?
It's not hard and it's fun.

I hate physics however. I blame my professor physics for this.

u know, i totally understood that

BrokenSaint wrote:OMG WIKIPEDIA!!!

Yeah >_> just copy and paste articles

would be easier to post just the links so it doesnt have to be 'updated' all the time;.. lol

Nevertheless the subjects are interesting, I read about these subjects some time ago ^^

And its a nice compilation

takolin wrote:

shadowman20875 wrote:this and organic chemistry

QUARKS! QUARKS! QUARKS! QUARKS!

find the missing quark and we rule the universe!!! muahahhaha

well no we wouldnt, but its just as big for physics researchers

How can one not love organic chem?
It's not hard and it's fun.

I hate physics however. I blame my professor physics for this.

too many carbons. At first its fun w/ hydrocarbons then oxygen come in for functional groups, after that nitrogen comes and then helium, at that point I hate it, i did get an A in a prep course for it though, it was just annoying.

And PureOwange... QUARKS QUARKS QUARKS! everyone loves quarks

Helium in organic chem?
It starts with Carbon and hydrogen.
Next are oxygen, nitrogen, chlorine, fluorine, Iodine and bromine.
The next step would be sulphur, phosphorous, silicon, Boron
And then we'd have Sodium, potassium, magnesium and many other metals as catalysts, salts and other things.

Yet I don't know how one can put helium in there.
Helium and Neon are practically inert.
The other noble gasses can react with fluorine and Xenon even with oxygen.
Although it's not something usual.
.

takolin wrote:Helium in organic chem?
It starts with Carbon and hydrogen.
Next are oxygen, nitrogen, chlorine, fluorine, Iodine and bromine.
The next step would be sulphur, phosphorous, silicon, Boron
And then we'd have Sodium, potassium, magnesium and many other metals as catalysts, salts and other things.

Yet I don't know how one can put helium in there.
Helium and Neon are practically inert.
The other noble gasses can react with fluorine and Xenon even with oxygen.
Although it's not something usual.
.

hm.... would explain y i hated the class , and yes, we had a short section about helium... i cant recall under what though, maybe if i still had my book

and Xenon is werid... kinda like bromine, but thats not organic

Bromine can be organic.

takolin wrote:Bromine can be organic.

is bromine the one that bonds three ways? wait no, thats boron, but yeah... BOO ORGANIC CHEM!!

-returns to quantum physics-
awww unproven stuff

Bromine is like chlorine but less reactive.
It only has 1 bond in organic chem (CH3CH2Br).
Up to 4 in anorganic chem as HBr04 Perbromicacid.