AS DAMP squibs go, it was quite a spectacular one. Amid great pomp and ceremony - not to mention dark offstage rumblings that the end of the world was nigh - the Large Hadron Collider (LHC), the world's mightiest particle smasher, fired up in September last year. Nine days later a short circuit and a catastrophic leak of liquid helium ignominiously shut the machine down.
Now for take two. Any day now, if all goes to plan, proton beams will start racing all the way round the ring deep beneath CERN, the LHC's home on the outskirts of Geneva, Switzerland.
Nobel laureate Steven Weinberg is worried. It's not that he thinks the LHC will create a black hole that will engulf the planet, or even that the restart will end in a technical debacle like last year's. No: he's actually worried that the LHC will find what some call the "God particle", the popular and embarrassingly grandiose moniker for the hitherto undetected Higgs boson.
"I'm terrified," he says. "Discovering just the Higgs would really be a crisis."
Why so? Evidence for the Higgs would be the capstone of an edifice that particle physicists have been building for half a century - the phenomenally successful theory known simply as the standard model. It describes all known particles, as well as three of the four forces that act on them: electromagnetism and the weak and strong nuclear forces.
It is also manifestly incomplete. We know from what the theory doesn't explain that it must be just part of something much bigger. So if the LHC finds the Higgs and nothing but the Higgs, the standard model will be sewn up. But then particle physics will be at a dead end, with no clues where to turn next.
Hence Weinberg's fears. However, if the theorists are right, before it ever finds the Higgs, the LHC will see the first outline of something far bigger: the grand, overarching theory known as supersymmetry. SUSY, as it is endearingly called, is a daring theory that doubles the number of particles needed to explain the world. And it could be just what particle physicists need to set them on the path to fresh enlightenment.
So what's so wrong with the standard model? First off, there are some obvious sins of omission. It has nothing whatsoever to say about the fourth fundamental force of nature, gravity, and it is also silent on the nature of dark matter. Dark matter is no trivial matter: if our interpretation of certain astronomical observations is correct, the stuff outweighs conventional matter in the cosmos by more than 4 to 1.
Ironically enough, though, the real trouble begins with the Higgs. The Higgs came about to solve a truly massive problem: the fact that the basic building blocks of ordinary matter (things such as electrons and quarks, collectively known as fermions) and the particles that carry forces (collectively called bosons) all have a property we call mass. Theories could see no rhyme or reason in particles' masses and could not predict them; they had to be measured in experiments and added into the theory by hand.
These "free parameters" were embarrassing loose threads in the theories that were being woven together to form what eventually became the standard model. In 1964,Peter Higgs of the University of Edinburgh, UK, and François Englert and Robert Brout of the Free University of Brussels (ULB) in Belgium independently hit upon a way to tie them up.
That mechanism was an unseen quantum field that suffuses the entire cosmos. Later dubbed the Higgs field, it imparts mass to all particles. The mass an elementary particle such as an electron or quark acquires depends on the strength of its interactions with the Higgs field, whose "quanta" are Higgs bosons.
Fields like this are key to the standard model as they describe how the electromagnetic and the weak and strong nuclear forces act on particles through the exchange of various bosons - the W and Z particles, gluons and photons. But the Higgs theory, though elegant, comes with a nasty sting in its tail: what is the mass of the Higgs itself? It should consist of a core mass plus contributions from its interactions with all the other elementary particles. When you tot up those contributions, the Higgs mass balloons out of control.
The experimental clues we already have suggest that the Higgs's mass should lie somewhere between 114 and 180 gigaelectronvolts - between 120 and 190 times the mass of a proton or neutron, and easily the sort of energy the LHC can reach. Theory, however, comes up with values 17 or 18 orders of magnitude greater - a catastrophic discrepancy dubbed "the hierarchy problem". The only way to get rid of it in the standard model is to fine-tune certain parameters with an accuracy of 1 part in 1034, something that physicists find unnatural and abhorrent.
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Have your say
Dark matter and dark energy are band aids to a broken model. Why invents this instead of changing the theory of gravity. After all we don't know what gravity is all about. Just as valid is the theory that there is no gravity, the Earth sucks
I'm sorry such an excellent lucid article gets such vapid comments. Bringing together the threads of SUSy makes it a pretty compelling theorem, I never knew Neutralinos were a spot-perfect explanation for dark matter.
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Dark Matter
Fri Nov 13 00:12:49 GMT 2009 by Dennis
http://freetubetv.net
Higgs boson?
I was more intrigued by:
"cluster emits a million times more light than the sun"
If only we could harness that power we'd have unlimited energy. Especially if we could find a way to stockpile that energy in the same way we do with a battery.
You quite clearly have no idea about physics. A field is not the gradient of the potential..the field is the potential with the force as the gradient. A-level physics
There are numerous attempts to modify theory of gravity (that is, more or less, General relativity) in order to get rid of dark matter. None so far has produced anything simpler or more elegant than the "standard" theory plus dark matter
Even if susy is found we still have the much bigger Q. , what is the source / mechanism that produced all natural laws ??
That is a bigger question - one that as of now we have little idea how to tackle. Currently we have a path forward, so we're following it.
It'll be interesting and strange to see how people attempt to tackle that question... I doubt deductive reasoning will be possible in such a pursuit. We're limited to inductive reasoning because we can never see outside our own universe (so it seems).
I would like to elaborate a little ; in our very limited scientific reality ( not ontological one) we know of mass/energy and space/time and the children of science invent meta-something to ""explain"" the origin of what we know , now NO one can in principle invent any thing to explain the origin of 1- laws of nature 2- why mass/energy/space/time obays laws of nature.
>> NO one can in principle invent any thing to explain the origin of the laws of nature.
But people can invent mechanisms that satisfactorily answer the question. For example, imagine a hypothetical reality of infinite size where different random things occured everywhere... different laws here, different rules there... anything and any rules you can possibly make up. Now, in this reality, somewhere, you would find laws that created objects with mass, and on those objects the laws allowed living things to evolve. Those living things may ask, why are the laws the way they are? where did we come from? and the answer is... there is no meaning... they're just random... only you happen to be living in the bit that's conducive to life.
You may ask... well why does this reality have all these random laws and rules? why is there anything? why isn't there just nothing?
The answer is that there are a lot more ways of there being random stuff, there's only one way for there to be nothing. And besides, every possible scenario where reality is nothing does not have a human there to witness it. The question why isn't it just nothing is a bit like asking why aren't I dead?
Max Tegmark is having a go at explaining the origin of everything with his ultimate ensemble theory.
See http://en.wikipedia.org/wiki/Mathematical_universe_hypothesis for a brief overview.
"Why is there something rather than nothing?" or "Why are there physical laws?"
Physical law harnesses chance, making existence possible.
What is physical law?
Physical law is a limitation on possibility.
Why does physical law exist?
Because possibility for anything also includes possibility for limitation of possibility. So the limitation exists. Of course, at this level, there is no spacetime - so its pointless to say 'possibility implies limitation will exist at some point in time'.
What is the nature of this limitation?
Its probably not a categorical limitation. Its rather a minute skewing of this possibility in some way(s). This skewing then adds up over multiple instances to give the impression of physical law.
What would be really cool?
Finding out what is the minimum number of ways the skewing has to happen for our universe to exist?
Where did the potential come from / what is its nature?
Unanswered for now. But we know it has no nature, because that would be physical law (limitation).
(1)Because there are no other laws for them to obey and (2) Because they have nothing else to do.
"We're limited to inductive reasoning because we can never see outside our own universe (so it seems)."
I see your point, yet the outcome of this way of reasoning can also be turned inside out:
We're limited to deduction, because we can never see outside our own universe, whilst there is more to be seen if we are to understand the big why.
If you needed to deduce (pare down, make smaller) a grand theory that you could see standing outside the universe (or it came to you in some fantastical manner) - all work would cease. Job done.
What do you mean!!?
When was the number Pi created ?
When was the function d/dx = x^2 created ?
Mathematical functions and numbers are not created but always existed. They exist independently of the universe. In this way every possible mathematical function exists, including those that describe our world.
As a corolarry, every possible world exist.
Not a scientific theory but an interesting idea ?
let me explain to you : you know the relation ( mass /energy distribution = form of space/ time) ? o.k. now you tell me ; if this relation is an ontological fact --a very big if -- and it is eternal as you claim, then what direct mass /energy and its distribution and space and time to behave to exactly satisfy this relation ? or as s.hawking said : what breathes fire in the equations to build a universe ? dear sir : this is a very big point to grasp not just for arguing.
I'm sorry, but, to have the arrogance to want to ask "The Big Why" is really putting the cart before the horse. So is attempting to explain the workings of the universe - at this time.
Humans have never been off the planet (well, 24 of us have been to the moon which is still in earth orbit). We still have wars, we are very superstitious - believing in unseen forces like gods and angels, and we spend most of our time interacting on a purely emotional and instinctual level. Our planet is so infinitesimally small compared to the universe. And, by the way, all we can really see of it is emitted radiation which we have no concrete evidence of its origin - we have various names for these "lights" in the sky: stars, galaxies, quasars, etc... Before we start asking the "big whys" lets start with what is right in front of us. The LHC is a good start and so is making peace with our fellow humans.
Mathmatical numbers and equations do not "exist" in any real sense. We define numbers. We define what "equals" and "plus" and "squared" and etc. mean. It is an intellectual self-contained system that we use for many purposes, including describing the behavior of things that actually do exist.
The number of possible mathmatical functions is infinite, and creating one (x(2) + y(2) = z(2) for instance) does not limit the number or functions. E.g. x(2) + y(2) + x - x = z(2) is just as legit, and you can go on creating variations of just that one equation forever.
The existence of worlds is not a corollary, as there you are talking about things that actually exist outside of an intellectual system that can be used to describe it.
See the difference?
The Big Why
Thu Nov 19 00:27:35 GMT 2009 by Zephir
http://aetherwavetheory.blogspot.com/2009/02/awt-and-zeta-function.html
In AWT Pi number is closely related to particle system concept, i.e. most random arrangement of particles. AWT is based on assumption, everything is composed of many smaller objects - in this sense, Pi was established in the moment, when Universe becomed Multiverse.
(long URL - click here)
(long URL - click here)
I believe the answer is, "don't know". But if the question can be asked, then the answer can be pursued. Maybe one day someone will really be able to explain how something can arise from nothing.
Why something must arise from nothing ? why we are deleting our power of reason and rationality ? why do we have to believe the unbelievable ? some one please tell me : why this escape from god of the bible ??? what if this day someone can prove that something CANNOT arise from NO-thing ...real nothing not bluffing deciet of false nothing.
And FINALLY he comes out with it! SO bleeding obvious this guy is just another Bible Basher.
Unable to accept that a mathematically perfect universe could simply exist they try to explain it away with the idea that it was created by a concious existence, based on a book riddled with inconsistencies, of a God who tells his "people" to slaughter innocent men, women and children, of a God who screwed up creation so badly the first time that he wipes the face of the earth clean with a huge flood, saving one family and an inconceivable number of animals in a boat.
Gog-believers are simply people who claim humility and yet are too full of pride to accept the fact that their own existence is finite.
The idea of your God is preposterous, and for you to suggest a mathematically perfect could NOT exist without being created, but that a supremely flawed consciousness, in the form of God, could is the height of irrationality.
The question is nonsensical: "why does existence exist and non-existence not exist?"
Anyway, if you're comparing existences, perhaps I could ask 'Why there is a god and not nothing?'
After all god would be something so it is part of your question. Note that God may be classified as non-contingent but that doesn't mean he necessarily exist and so any claims of necessity would need to be demonstrated. I don't think that's been done so far.
Considering that the LHC will be operating at over three times the capacity of the Tevatron in it's first year alone, in itself half the total potential energy the LHC can produce in total, I think we're in for some serious discovery. It's unfortunate that things went awry, but this is the most complex piece of machinery ever made by humankind - we'd be naive not to expect a gremlin or two.
I'd love to be involved with it all. Can't wait to see what pings off from these collisions!
Awesome Potential
Wed Nov 11 19:08:07 GMT 2009 by Dirk Bruere
http://www.neopax.com
Of course, the real nightmare scenario is spending billions on a machine that reveals no new physics at all. The Big Physics gravy train would be terminally derailed.
I agree and disagree. PR wise, no definitive find will be a blow to the LHC and its proponents. However, even a negative results gives physicists plenty to work with... it excludes all kinds of solutions, and directs their work towards things not excluded by the lack of results.
Lets just face it. Its going to produce a supersymmetric black hole - and that will be the end of that.
Absolutely. Someone famous said something approximately like "in terms of discovery, science is as much about not finding things as it is about breakthroughs, perhaps more so". I forget who.
I just love the ambition of it. That much money, that much expertise and planning and building, all for science. It makes a change for that level of effort being expended on something that isn't designed to flatten cities or line pockets.
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