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What are Superstrings?

Superstrings help support the theory of how the universe formed following the Big Bang.
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Superstrings, or superstring theory, is an exciting field of physics sometimes called The Theory of Everything. It is thought by many to be the elusive unifying explanation Einstein sought that could account for all known forces in the universe.

Until superstrings came along, scientists had two opposing theories for how the laws of nature behaved: Einstein's General Theory of Relativity and Quantum Mechanics.

General Relativity explains the world as we know it on a rather massive scale. It describes spacetime as a fabric warped by mass accounting for orbital systems, galaxies and the force of gravity. But these laws break down at the quantum level where a subatomic particle cannot be measured in terms of its exact position in space at a given time. It is also as likely to move backward in time as it is to move forward, and can even appear to be in two places simultaneously. The world of the infinitesimally small is so bizarre, scientists coined the term "quantum weirdness" to describe it.

The problem for physicists was to come up with a theory that would unite the world that we know with the quantum world. One explanation to account for all four known forces: gravity, the strong and weak nuclear forces, and electromagnetism. Superstrings might be that answer.

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Through mathematical equations it became obvious that the way we had previously thought of particles as "points" or "little balls" of energy was inaccurate. These tiny bits of matter actually behaved more like wiggling, vibrating strings. Strings are so small that Brian Greene, a physicist and proponent, explains that if a single atom were the size of our solar system, a string would only be the size of a tree. Yet strings make up all matter from the quantum level up.

The way strings vibrate determine the specific properties of each and every particle, likening the universe to a cosmic symphony of superstrings. But to rid the theory of mathematical anomalies, six extra dimensions were necessary. The six extra dimensions form tiny, curled up 6-D shapes at every point within our space. Inside these 6-D shapes are the strings of superstring theory. The six extra dimensions, plus our three, meant there were really 9 dimensions. Add one more for time, and the total was 10 dimensions. As surprising as this was, it wasn't the end.

In 1995 differing theories of superstrings presented a conundrum until M-theory united them. The only catch? M-theory mathematically required an 11th dimension. This presented a new picture of strings whereby, given enough energy, a string could stretch to become an extremely large floating membrane, called a brane for short. Branes can have different dimensional properties and grow as large as a universe. In fact, according to the theory, our entire universe exists on a floating brane -- just one of several floating branes that each support their own parallel universe. Each brane represents one slice of a higher dimensional space or bulk.

Though the Standard Model of the 1970's already united three of the four forces in a unified theory, gravity could not be reconciled with the three quantum forces. But a breakthrough in superstrings encompassed the elusive force of gravity, whispering of the Holy Grail of physics. If a massless hypothetical particle responsible for transmitting gravity -- the graviton -- exists at the quantum level as a closed string, this would present a direct gravitational link to the theory of superstrings.

The theory predicts strings can be open or closed. Open strings, or strings that resemble little wiggling hairs have at least one endpoint "attached" to the membrane like a trolley car is attached by a top cable to an electric line. Strings can move through the brane but cannot leave it, explaining why we can't physically see out of, or reach out of our dimension. The atoms that make up our bodies are composed of open strings that have attached endpoints to our 3-D membrane. Another way to look at it is to consider a movie screen. People on a screen appear to be three-dimensional, but they cannot actually reach off the screen into our 3-D world. They are stuck in their 2-D world, just as we are stuck in our 3-D world and cannot reach into neighboring dimensions. Scientists refer to this as degrees of freedom.

But the graviton is different. As a closed string or loop without attached endpoints it was theorized that it might be able to escape our 3-D brane and seep into other dimensions. This would explain why gravity is many times weaker than the other forces.

However, what if the inverse were true? What if gravity on a parallel brane is as strong as the other forces, but is weaker here because it is only leaking into our dimension? Mathematically, the theory of superstrings again worked beautifully and finally put forth a plausible explanation for the weakness of gravity while uniting it with the other three forces.

There was just one hurdle left: The unifying theory should also be able to explain the Big Bang. Four physicists traveling together on a train casually tackled this subject. One of them put forth the question, What would happen if two branes collided? The plausible mathematical answer turned out to be the Big Bang.

Detractors of the theory of superstrings point to lack of proof and the difficulty in providing it. Is it just a beautiful mathematical construct? A philosophy? Or a true explanation of our world? No other theory has come close to mathematically unifying all four forces, much less additionally providing an explanation for the Big Bang. But proving that other dimensions exist -- floating branes and parallel universes -- has been a major sticking point.

Nevertheless, believers of the elegant theory are eager to see it proven, and scientists have since found that there may be observable proof of astronomically large strings. Thus, the theory of superstrings continues to gain ground. In the end, if successful, from 11 dimensions to parallel universes, from the swirling galaxies to quantum soup, superstrings might just truly be The Theory of Everything.

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anon312489
Post 13

People of science and people of religion! I have decided to put you out of your misery with one clue. The universe is, in fact, a gigantic energy storage mechanism. Life is an unintended side effect, no more useful than unwanted algae on the glass of an aquarium. Get this through your heads. Respect of each other leads to survival and progress. Disrespect leads to the opposite.

anon305191
Post 12

I enjoyed listening to the above comments and I would like to provide just a little wisdom and knowledge. Scientists have not a clue in discovering how God created the world. We must understand the mind that rebelled against God's plan is not the mind that can understand God's plan.

Think about it: can an old computer built fifty years ago understand windows 96? If it is not on the hard drive, it cannot think beyond its memory. We must upgrade our mind to operate at and beyond the speed of light and then we will be able to understand (the mind of Christ). Good luck. You can do it.

anon141236
Post 11

It's not cool when you guys talk to Christians and people who have a religion like they're blind and stupid. I myself am a Christian. But i'm not a sucker. I don't just believe what i believe for no reason whatsoever. I wouldn't waste my time believing in something just because.

So don't address the billions of people across the globe who believe in God like they're all dumb and below you. You honestly think that the billions of people across the globe who believe in God are all just dumb and believe it for no reason?

anon92811
Post 10

To anyone who believes that we can solve all the mysteries of the universe and that it will put an end of religion, you are off your rocker. What we will know in three hundred years will dwarf what we know now. Even if the supposed Singularity proposed by Raymond Kurzweil occurs (whether it's the invention of artificial intelligence or the means of controlling energy fusion) we will never know the entire truth to our universe.

Do you believe that the Big Bang was when it all started? Why couldn't there have been something before the Big Bang? We know nothing, and it shall remain so. We may learn how to copy the Big Bang, but we will never know if there was anything before. Unless, of course, we discover that we can indeed travel beyond the speed of light and learn to do, but that opens up a bucket load of new possibilities.

anon60226
Post 9

What about if gravity is like how Einstein explained it? What about if gravity was the 'consequence' of piling matter and not caused by a single particle like the photon? It's like a drunk guy ; alone he doesn't do much but with many other drunk guys, there'll certainly be a fight amongst them (the fight is like gravity is that example).

'Fight' is not something you can touch or feel, but it certainly does exist as it can affect you in many ways (bruises, etc...) Same goes for gravity. Why is that so? Because that's how it is.

anon48630
Post 8

If the large hadron collider can create new matter like many believe it will, then we will in a sense have the blueprint to create our own universe. we will be able to match God's greatest achievement. It will be the death of religion.

anon25257
Post 7

"Posted by: anon16517

Why don't you try asking God? After all, he created the whole show.

I'm a scientist too, but don't believe this new outlandish theory which was compiled after drinking much wine.

Strange thing is that many scientists go to church. Why?"

First of all, what god? You claim he created the whole show... how do you know? As a "scientist" as you claim, you should have evidence before making a claim you can't support. What evidence do you have that this "outlandish theory" was compiled after much wine?

Oddly enough, there is more evidence for this theory than there is for any god. The evidence is the math. Its not much, but certainly more than any God hypothesis has been able to provide.

drkennyg
Post 6

I'm with anon16517

I'm a Christian and that's why I go to church now after being absent so long. My trouble was that I believed too many bad theories and not the best book of all, the Bible. Creation by God and salvation through Christ makes perfect sense.

anon17875
Post 5

"Strange thing is that many scientists go to church"

ooow, enough of that already, not many in the only meaningful way: relative.

Why do the ones that go to church go to church?

Like everyone else that goes to church, because their parents went and they went along.

drkennyg
Post 4

Basically string theory is pretty much bunk as far as I'm concerned. I think physicists should first find out a good understanding of what gravity IS. We all know how to measure and account for it but nobody knows why it is just so. I also find no conflict in thinking of the macro world of Newtonian Physics one way and Quantum Physics in another way. Why should they be connected anyhow just because it would be tidy.

anon16543
Post 3

The black hole experiment has no bearing that I know of in regards to proving superstring theory. And no, there is no need to worry. :)

tae
Post 2

I just saw an interview with a physicist where an international group of scientists are going to create a small black hole. Will their experiment be able to prove or disprove the theory of the superstring, and should we be worried?

anon16517
Post 1

Why don't you try asking God? After all, he created the whole show.

I'm a scientist too, but don't believe this new outlandish theory which was compiled after drinking much wine.

Strange thing is that many scientists go to church. Why?

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