Braneworld Cosmology And Why It's Important

It’s now time to launch another thread, one that is somewhat overdue as a means of transporting posts from the old version of these forums to the new version, and one that covers a topic that will be of much utility value in the future.

But before revisiting that past material, I need to provide a little background, and a little history, to explain certain key concepts covered in my past posts.

Quite a few people have, by now, no doubt heard of string theory, which was originally launched as a means of solving some difficult problems in particle physics, by treating those particles as one-dimensional vibrating “strings”. String theory has long since expanded its remit from these beginnings, not least because cosmological physicists realised fairly quickly, that the mathematical tools of string theory could also be applied to problems in the field of cosmology, and thus began the earnest pursuit by physicists of string theory as a possible candidate “theory of everything”, because its findings could apply both to the small and the large scale, in the absence of a fully working theory of quantum gravity. Indeed, one of the hopes that physicists had for string theory, is that it would point them toward that longed-for fully working theory of quantum gravity, but I digress.

Given the early promise string theory offered when first launched, it’s not surprising that it became popular among cutting-edge physicists. As a corollary of this popularity, other frameworks in physics took something of a back seat, one of these being supergravity, but in one of those amusing twists of scientific history, some interesting developments arose, in no small part due to the popularity of string theory and its extensions.

One of those extensions took the form of asking the question, “if we’re going to extend particles into one dimensional entities, why stop there?” Cosmologists, for various reasons, started pushing this particular envelope quickly, and started investigating whether or not objects of two and more dimensions, analogous to strings, were [1] possible, and [2] consistent with known physics. The answer to both questions was quickly determined to be a resounding “yes”, and so, what has come to be known as braneworld theory was launched - a natural, if mathematically intense, extension of string theory.

Briefly, a brane (the word being a contraction of “membrane”) is any object that plays the role of a fundamental entity in physics, be it a unit of spacetime or a particle like entity. Prefixing the word “brane” with a number tells you how many dimensions the brane in particular has - 0-branes are point particles, 1-branes are strings, and then we have 2-branes (sheet like entities) and upward.

There are, however, some restrictions on what is possible with branes. One important restriction being that they have to behave in a manner consistent with mathematical entities known as manifolds, which are, in effect, a means of defining generalisations of geometrical spaces. However, while the requirement to be, in effect, a manifold, places some restrictions upon brane behaviour, manifolds are themselves flexible and powerful objects, sometimes imbued with additional rich structure, so for example manifolds can have topologies associated with them, and can also be capable of supporting calculus operations or linear algebra operations upon them.

One important aspect of manifolds, is that multi-dimensional manifolds can be compactified - namely, subject to various mathematical transformations that shrink extra space dimensions “out of sight”, so to speak, while leaving the three familiar space dimensions macroscopically visible.

This ability to compactifty manifolds makes them eminently suitable as environments for string theory or M-theory operations, and one particular class of manifolds, namely Calabi-Yau manifolds, play a pivotal role in more recent string theory and M-theory work.

Now, it’s at this point that we encounter the twist of history I briefly alluded to above. This arises from the fact that physicists had an embarrassment of riches arising from 10-dimensional string theory - they had no less than five variations on the theme, all of which were internally consistent, and capable of modelling the universe as we know it, but with no means of determining which of those five variations was the one applicable to the observable universe. No test, either mathematical or empirical, existed to distinguish between the five.

It’s at this point that supergravity, or its more developed form, M-theory, made a resurgence. Courtesy of the fact that it was found that those five 10-dimensional string theory models were subsets of one, overarching, 11-dimensional M-theory model.

It was at this point that two physicists working in this framework, Paul Steinhardt & Neil Turok, made an interesting discovery. Namely, that it was possible to build 10-dimensional branes out of Calabi-Yau manifolds, have them move freely in a larger 11-dimensional space, and then work out what happens when two such branes collide.

This turned out to be a particularly elegant means of instantiating a universe such as the one we observe ourselves to inhabit. Elegant because it solved two major problems arising from standard Big Bang cosmology - namely, how to deal with the “singularity problem”, and how to supply energy to the newly instantiated universe, facilitating matter synthesis. In the case of the singularity problem, that quite simply vanished, and an exchange of energy between the colliding branes and the newly instantiated universe (itself residing in a new, causally disconnected brane after the collision) solved the initial energy input problem.

There’s another elegant feature to this work, however. Namely, that it provides a testable prediction.

One of the consequences of the braneworld collision envisaged by Steinhardt & Turok, is that primordial gravitational waves are sent rippling through the newly instantiated universe at the start. Each of these primordial gravitational waves has a wavelength. But the fun part is, these wavelengths conform to a pattern, known as a power spectrum.

To construct a power spectrum, you plot wavelength on the x-axis of a graph, and amplitude (or frequency of occurrence, which is a proxy for amplitude thanks to wave superposition) on the y axis. The resulting graph is a power spectrum for the waves being observed, and power spectra for light sources are wonderfully informative about the behaviour of those light sources.

If your graph is a flat straight line, then your measuring instruments are receiving waves of all wavelengths in equal quantity. If on the other hand, the graph is a sloping line or a curve, then that power spectrum is biased in favour of specific wavelengths, which tells you that some interesting processes are taking place.

This is where Steinhardt & Turok score highly at this point, because their braneworld collision model predicts that the power spectrum for primordial gravitational waves will be biased in favour of short wavelengths. This prediction is one of the main motivating factors behind the recent rush to build working gravitational wave detectors by scientists - precisely to test that prediction.

Of course, there’s much work to be done first, such as learning how to discriminate between primordial gravitational waves, and gravitational waves of more recent origin, such as those arising from black hole mergers. But once the requisite groundwork has been completed, that prediction will be tested, and if that predicted power spectrum is found in the data, Steinhardt & Turok pick up a Nobel Prize.

From this point on, I’ll not only be providing as complete an exposition of the papers in question as I can, but some interesting ramifications that arise from this braneworld collision model being found to be applicable to the instantiation of our observable universe. Life will become very interesting indeed when I cover those ramifications. Watch this space!

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Having whetted everyone’s appetite with the introductory post above, it’s now time to present those papers by Steinhardt & Turok!

So, without further ado, I present to you … (drum roll) …

Testing The Braneworld Collision Theory for the Big Bang

Allow me to present two scientific papers by Neil Turok, one of the world’s leading theoretical physicists, which contain the exposition of a testable naturalistic mechanism for the instantiation of the observable universe:

Colliding Branes In Heterotic M-Theory by Jean-Luc Jehners, Paul McFadden and Neil Turok, (12 February 2007) [Download from here]

Generating Ekpyrotic Curvature Perturbations Before The Big Bang by Jean-Luc Lehners, Paul McFadden, Neil Turok & Paul J. Steinhardt,, 19th February 2007 [Download from here]

Let’s look at the first of the above two scientific papers. The abstract reads as follows:

The paper goes on to state as its conclusions:

Reference [24] cited above is the second paper I listed earlier, which was described as being “in press” at the time of the publication of the first paper. This second paper opens with the following:

The conclusions of this paper are as follows:

In other words, the two papers, taken together, provide not only a mechanism for the formation of the universe using a pre-Big-Bang physics that is consistent with the known physics of our universe, but also provides a means of testing experimentally whether or not the conclusions of the authors are correct, namely by analysing the spectrum of gravitational waves passing through the universe. If that spectrum of waves is observed to be shifted toward shorter wavelengths, then this provides confirmation that the authors have alighted upon a mechanism that is consistent with observational reality. Which, needless to say, is why research and development money is now being devoted to the matter of gravitational wave detection, so that this question can be answered either way. Therefore we have a real world phenomenon to observe that will provide an answer as to whether Turok et al have alighted upon a consistent mechanism that is in accord with observational reality for the formation of the known universe, a mechanism moreover that allows the formation of other, causally separated universes and which may even, in the fullness of time, allow us to experimentally form new universes via laboratory means.

Note how I ended the above paragraph. Build a sufficiently sophisticated particle accelerator that would be capable of reproducing the requisite conditions, and that particle accelerator could spawn a new universe by fostering an appropriate braneworld collision. Of course, getting to the point where this is an engineering reality is the hard part, but the above papers make it theoretically possible. All we would need to be able to do is generate a positive-tension brane and a negative-tension brane by appropriate means in a suitable piece of experimental apparatus, collide them, and a new universe would be the result. Of course, that new universe would become causally separated from ours in a very short space of time (around 10-35 seconds), so we would have to devise means of detecting events upon such a tiny time scale to allow us to confirm that we had indeed succeeded in doing this in a laboratory experiment, but the fact that we would be able to do so by the simple expedient of harnessing natural processes would make any supernatural “creator” utterly irrelevant. After all, if we could construct a machine that could perform this function, using nothing more than an application of physics, the idea that some magical entity was a necessary requirement would be dead in the water.

Oh look. A testable mechanism for the instantiation of the universe, and all the matter contained therein, that doesn’t need an invisible Magic Man. I’d describe this as “Game Over” for supernaturalism the moment empirical data verify this.

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@Calilasseia good sir, I think you need to smoke far MORE weed than you already do. I think you could benefit the whole community by simply testing the limits of your intellect.

What I gather from the topic is that, given enough variables, anything and everything can be modelled by mathematical formuli

As you’ve no doubt gathered from my prime series summation (which you refuse to acknowledge) - the art of mapping reality to perception is a slight of hand; a gesture of a supreme intellect

All things aside - why have you REALLY stalled at remarking on my formulae?

Maybe because you have a history of making child molester accusations against your critics?

I’ll skip the unexpected tangential diversion, and move on as planned to the post I had compiled in advance covering ramifications of Steinhardt & Turok’s model. :slight_smile:

Having whetted the appetite of one or two people with my earlier announcement about ramifications, it’s now time to try and live up to the billing therein. I’ll begin by announcing that what follows is, by my own admission, a speculative piece, but one that is grounded in current cosmological physics, and on that basis, stands more chance of becoming reality than any number of fantastic and absurd mythological assertions. Yes, I am honestly presenting what follows as speculation, but at the same time, this speculation is grounded in peer reviewed physics, and as such, is far more likely to come to pass than mythology based wibblings. In short, buckle up, people, you’re in for a roller coaster ride.

One of the perennially observed features of supernaturalists, is that they never consider any candidates for the ‘god’ role, other than the candidate they favour from their particular choice of mythology. None of them ever ask themselves the question “What if the god that actually exists, is something different from the one I favour?” One of the hilarious ironies of the entire business of interacting with supernaturalists, is that I’ve probably asked myself a variant of this question (said variant taking into account that I don’t have a candidate pre-selected for the role), more often of late than practically every supernaturalist I’ve encountered has asked said question in their entire lives. One of the more interesting hypothetical scenarios arising therefrom, I shall now present.

For the purpose of this hypothetical scenario, I shall refer to the above exposition I have just given, on two papers published by Paul Steinhardt & Neil Turok, in which they presented a possible testable natural process for the instantiation of the observable universe and its contents, and which has observable consequences in this universe once said process has launched its instantiation mechanism.

In that post, I briefly explored the possibility of some future physicists being in a position to test the mechanism contained in those papers experimentally, but in that post, I was primarily interested in such experimentation being a “Game Over” moment for supernaturalist assertions, courtesy of the fact that the moment testable natural processes are demonstrated to be sufficient to explain a given class of entities and phenomena, supernatural entities become superfluous to requirements and irrelevant from that point on. Here, however, I want to explore an entirely different set of concepts.

Let us hypothesise, for this scenario, that the following have been established:

[1] The evidence for the Steinhardt-Turok braneworld collision mechanism described in those papers is, in the future, alighted upon by gravitational wave detectors;

[2] In that future, progress is made with respect to the relevant physics, to the point where the Steinhardt-Turok mechanism becomes directly testable in the laboratory;

[3] In that future, the requisite effort to build a laboratory to perform that experiment is exerted, the laboratory is constructed, and becomes operational.

So, the grand day arrives, when the laboratory becomes operational, and the scientists staffing said laboratory prepare for their grand experiment - the instantiation of an entirely new universe in the laboratory. The requisite experiment is run, and in a very short space of time, the data returning from the laboratory instruments indicates that the experiment has been a resounding success.

At this point, several ramifications are immediately brought home. The first being that, if one defines a ‘god’ as ‘any entity capable of instantiating a universe’, then that laboratory, its apparatus, and its scientist staff, treated as a single entity, are, in effect, the god of that newly instantiated universe. That this fact would probably cause a good few supernaturalists reading the news headlines to blow an artery the moment they woke up to this, is irrelevant to my point. The moment that experiment is successfully concluded, we would have hard evidence that the laboratory in question, its equipment and the scientists deploying said equipment, have collectively become the god of a new universe. Leaving aside for a moment any jokes about a universe produced by a committee that might spring to mind here, that hard evidence would naturally lead to the question of whether our universe had a similar origin. Of course, the scientists in that facility would simply point to their experiment, as hard evidence that our universe was the product of the same testable natural processes, and any speculation on whether those processes operated in a natural, unguided manner, or were pressed into service by like experimenters in a different universe, would probably remain unanswerable for a very long time.

But apart from destroying pretensions arising from mythological assertions wholesale, it would have a serious impact on the philosophical question of what sort of god, if any, actually exists out there. The moment some of our physicists become a de facto god for a new universe, it will only be natural for the philosophically inclined to ask whether our universe was the result of a similar past experiment by beings unknown.

Now, at the moment, the current state of knowledge in physics suggests that the moment a new universe is instantiated by this mechanism, it becomes detached from its origin in the requisite metric space, and causally disconnected therefrom. Which means that whilst those future scientists may be able to launch that new universe on its path, they are prevented by the laws of physics from finding out, from that point on, what is happening inside that newly launched universe. It becomes forever observationally sealed off from us. Which means that our new gods find themselves in the unusual position of being able to create a universe, but forever forbidden to observe its internals, let alone manipulate said internals. They would not merely be ‘deist’ gods in the sense of choosing not to intervene, but would be ‘deist’ gods in the sense of having no choice but to stay out of that universe’s affairs - if you like, ‘super-deist’ gods.

As a corollary, if that newly launched universe evolved in such a manner as to produce within its confines, intelligent life forms conceptually akin to ourselves (even if the physical details are radically different), any generation by those beings of mythologies akin to those our species has produced, along with assertions to the effect that typical mythological gods exist, will be known to us in advance to be a futile exercise. We, the species whose efforts launched that new universe on its way, will know what the inhabitants thereof cannot for a long time even fantasise about. But, we will also know that our causal disconnection from its point of origin of our universe, forever prevents us from knowing if our universe arose by unguided natural occurrence of the requisite process, or occurrence guided by sufficiently sophisticated experimenters. That causal disconnect is a barrier never to be crossed - at least, this is the current view arising from the requisite cosmological deliberations.

This also opens up a veritable supertanker load of ethical questions, but I do not consider myself qualified to give these even the most cursory of treatments at this stage, other than perhaps to present a small sample of the relevant questions, but that is a topic for its own thread methinks. However, those interested in some of the outstanding questions posed by this development, can track down the short story Non Serviam by Stanislav Lem, which presents interesting insights into an alternative “what if we become something else’s god” scenario.

However, even if the new physics allowing the hypothetical experiment presented above to become an engineering reality, also provides a means of overcoming that causal disconnect, and allows us to observe or even manipulate the contents of that universe to further our knowledge, there’s an immediate problem to be faced. As fantastic and magical as such a capability will seem - possibly even to some of the scientists who have just performed the experiment - the scientists in question will still be constrained by whatever laws of physics are in operation in the requisite realms. As well as the laws of braneworld physics, they will be constrained by whatever variation of the laws of physics is in operation in that newly instantiated universe. ‘Miracles’, in the sense of suspending those laws whenever it is administratively convenient, will be out of the question. They might also find themselves having to contend with a newly launched universe, in which the internal physical laws thereof are sufficiently different to those in operation here, to make even elementary observations and manipulations a formidable task. In short, those scientists will, if this scenario is ever realised, discover that being a god is monumentally hard work, and not something that any sensible individual would undertake lightly.

I’ll leave aside for the moment the interesting questions that arise, the moment one realises another very real possibility within this scenario. Namely, we know that the scientists operating that laboratory will eventually die. Chances are, that laboratory itself will only be a temporary affair, superseded by newer, better, more refined establishments. That universe launched by said laboratory will have been “created” by a temporary god. I’ll let that one sink in for a while.

Now some here might think I’ve compiled this exposition, in part at least, as a juicy schadenfreude dig at supernaturalists, but while my exposition makes such sport possible, that’s not the point. The point is, quite simply, that the world of ideas is as boundless as our imaginations, even when those imaginations are tempered by scientific knowledge, and exploration of the farthest reaches of the realm of ideas has been a defining characteristic of our species practically since the arrival thereof. Of course, care should be exercised to avoid nonsensical trajectories within that realm, but here lies two of my principal sources of exasperation with supernaturalists - one, the complete absence of any concern to avoid nonsensical trajectories within the space of ideas, if said nonsensical trajectories happen to be emotionally comforting, and two, the complete absence of any desire to explore speculative but essentially sensible trajectories that deviate from their current choices. Out of the myriad possibilities awaiting discovery by humans exerting at least some level of diligent effort, why should we be constrained by senile mythologies?

Indeed, the thought arose as I was writing this, that as well as validating the multiverse hypothesis, such an experiment would point to another conclusion. Namely, that any god genuinely responsible for the untold trillions of instantiated universes within the multiverse, would be far too busy being occupied as a full time research scientist tracking the diversity of behaviours of its products, to be in the least concerned with our petty obsessions with genitalia and doctrinal conformity.


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I’ve always wondered that if the creationists are right about God: is creation a unitary transform?

May be! But I’m hardly ever serious and when I feel comfortable there is almost nothing PC that I won’t joke about.

So, someone is a child molester? Big deal. I was molested as a child. I turned out okay. I have the RIGHT to jest over such things. I have victim status.

But what i’d really like to understand is the great lengths to which certain very smart people here are going to ignore my mathematical approximations.

And I just want a general opinion. Would I really call someone “child molester” because he or she was critical of my maths.

For goodness sake, Nyar - you thought I was trolling you when the index looked more like a multiple. How on earth could I predict you would interpret the formula that way?

It’s at least 45% better than the standard asymptotic 1/2n^2(log n) approximation. Fuck! wagging tongue a little recognition maybe?

Then get VERY serious, that is a very serious and damning accusation. You may treat it light, but for many it is VERY serious business.

I feel pain knowing you were abused in your youth. But that does not give reason to treat others with such disdain. By doing so your are perpetuating the cycle of abuse.

Thanks Calli, once again you have made what was to me, an impenetrable subject, a concept that my non mathematical brain can encompass and almost understand as a concept.

Thank you.

(snicker ***chortle ***)

You should make your own thread to shit into.

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Jeeze Louise. Cranky?

So you can speak for the mental state of all abuse victims then? And if your words diminish some other victims perspective and cause them to feel as if their experience is a joke, that is ok to victim shame victims because you’re a victim? How do you know someone isn’t in a place mentally where they are contemplating suicide after such life events, and you make a joke at their expense possibly pushing them to the final conclusion? Wielding such opinions in a public space is callous, indignant, and morally repugnant to other victims who aren’t in your mental state of not self harming. Coming from a family of narcissistic thinking like that is what drove me to almost commit homicide or suicide myself.

My father was a narcissistic, verbally, physically, and mentally abusive person. He believed since he was abused it was ok to joke about it, simple to say I didn’t find it a funny joke then, nor do I now. For someone to infer that “I turned out ok” doesn’t make it ok for me to laugh at the suffering I went through. To assume anyone can and should be able to laugh at abuse is down right narcissistic and belittling to other victims. Stuff like this just blows my mind still, it’s my RIGHT……rights have consequences that affect more than just yourself.

To anyone else out there that’s been abused please ignore this malfeasance none sense. Your experience is yours to deal with and feel about it as you choose to.

Sorry I know I’m new here, and posting a lot. But stuff like this is what drove me to be here. Thanks for having this space for me to express things like this. It truly is like shedding some awful weight I put on my own shoulders for no reason other than growing up with narcissistic family views.


You are new. And that is sort of the point. I may have implied in jest that a very thick skinned member of the board was a pedophile. Okay. Maybe it’s not funny to the SENSITIVES.

Where I come from, you can take the piss out of your friends and colleagues by calling them pedophiles. Heck! Where I’m from we readily admit to being pedophiles. And why? For the sake of the laugh - it’s a fucking joke, my friend.

If it wasn’t offensive and absolutely unspeakable we’d tell these jokes to our wives and see how that turned out.

Look at my interactions. I get called a “fucking idiot” a “complete moron” by people I have internet love for. I don’t care. It’s all a joke.

And if you’ve been molested as a child in the eighties then (obviously) it fucks you up. And you’re dad used to joke about it. So, seriously? We HAVE TO JOKE ABOUT IT IN ORDER TO ADMIT IT’S A REALITY WITHOUT ADMITTING THAT IT HAS INEXORABLY FUCKED US UP FOR LIFE.

So, in short. I spent a year banned from this site for making such comments and quite frankly I don’t appreciate that the past has been dug up so non-chalantly as if I didn’t incur a punishment for my politically incorrect comments. Or that I didn’t learn from that ban.

So, I’m coming off a one year ban. You’re hearing through the grapevine that I insinuated that someone was a pedophile. I’m TELLING YOU that I said it as a joke and I’ve explained why EVERYTHING should be open to humour - simply because humour is how we banish the elephant from the room.

No disrespect to your experiences. But that “thing” I said had context. I did not mean it literally. It was a joke taken in poor taste. But to me, like … fuck … it’s Groundhog Day … everything is fair play when it comes to humour.

That’s exactly why I love posters here like Tin Man and Cognostic. Cog flings just as much shit as that which is flung back at him. Tin Man has a soft heart and will go to any length to lighten the mood.

Me? I’ll talk about the size of someone’s penis. And insinuate that having a large penis makes one superior. And that small penises are like pieces of art for the rich.

You know? Just beating around the bush.

Nice to meet YOU! And thanks for the comment.


A joke is a joke only if EVERYONE in the room laughs.

If just one person does not laugh, then it is not a joke.

So again you speak of this “we” and what I can only surmise is bandwagon fallacy. If I find it acceptable and other people agree with me it’s true. I don’t see the difference in that line of thought vs a theists, so by that logic because other people believe in god so should I. Well thanks, guess I’m late for church then.

Again trying to reinforce your “right” with more nonsense. As I said plainly, your rights don’t end at you. Rights have far reaching consequences, most invisible to ourselves. Unfortunately much like life, you can’t undo what was said. Being an apologist doesn’t absolve you of indirect consequence. Your ends don’t justify your means in my opinion.

Also I don’t think it fucked me up for life. Self pity and narcissism go hand in hand. The victim can’t possibly ever be an abuser themselves after all right? I learned from it, and it molded me to be who I am. Your lack of respect for anyone else’s mental state is most alarming in this regard.

Oh so your punching down at victims who may still be working through their emotions? Your self aggrandizing position of talking down is more my gripe than anything you have said before. Speaking as if everyone should understand and accept your thoughts as you see them without context of your experience sounds a lot like a god complex to me. At the least narcissistic.

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Aw, dude! Soft hearted? ME??? What the HELL, Ratty? Don’t be telling the new guy shit like that! He might go getting the wrong impression about me. Soft hearted, huh? Hmph! :triumph: I’ll show you soft hearted!.. (digging through tool box)… Where the hell is my hatchet?.. Ah-ha! Here it is… (heading outside)… Heeeere, kitty-kitty-kitty…!

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You can’t win ‘em all.

Whatever shit they throw on you, I hope you know I high as a kite and just can’t write. Hope to God He doesn’t tell my wife.

secret psychonot

OMG How could you, A joke? You need "Jeeeeesus.’ Jeeeesus would tell you not to jest, EPH. 3-5 says, " But among you, as is proper among the saints, there must not be even a hint of sexual immorality, or of any kind of impurity, or of greed. Nor should there be obscenity, foolish talk, or crude which are out of character, but rather thanksgiving. 5For of this you can be sure: No immoral, impure, or greedy person (that is, an idolater), has any inheritance in the kingdom of Christ and of God.…’

Poor ratty, while the rest of us are playing our harps and heeding the word of God, and his only begotten son Jeeeeeesus. You will be burning in the pits of fiery hell. WAKE UP SON! You have offended the LORD. Jeeeeeesus is not on your side. WAKE UP! Jest Ye Not! Lead not others down this eeeeeevil path. WAKe UP. Drop you your knees and beg for God’s mercy. PRAISE the Lord Jesus, who forgives all things to those who ask with a sincere heart. Do it now, the end is at hand. DO IT NOW! Praise Jeeeeesus. Open your heart and let in the truth and the light that is Jeeeesus. Open your heart and beg forgivness or face eternal damnation for your slanderous act. Find SALVATION in God. Find SALVATION in God, FIND SALVATION IN GOD!!!