A vast cavern is the stage for tests to find the 'God particle'

Atlas holds key to scientists' map of Universe By Mark Henderson A vast cavern is the stage for tests to find the 'God particle'

SCIENTISTS have taken a step closer to finding the “God particle” that is thought to shape the Universe. In a concrete cavern 130ft deep and bigger than the nave of Canterbury Cathedral, they will mimic the high-energy conditions that existed fractions of a second after the Big Bang to study a beam of energy a quarter of the thickness of a human hair.

The vast Atlas cavern, which was completed last week at Cern, the European nuclear physics laboratory on the Franco-Swiss border, will house parts of a giant atom-smasher that is expected to solve the most elusive riddle in physics.

When the £1.5 billion Large Hadron Collider (LHC) is switched on in 2007, it will determine once and for all whether the Higgs boson, a mysterious fundamental particle held to give matter its mass, really exists. If the machine finds the boson, proposed by Professor Peter Higgs of Edinburgh University in 1964, it will prove that the Standard Model for the nature of the Universe is correct. If not, the maxims of modern physics will be thrown into disarray.

The boson was nicknamed the “God particle” by the Nobel laureate Leon Lederman for its centrality to the cosmos. Although it will be so small that its presence can only be calculated, not seen, the search for it requires some of the largest and most advanced scientific instruments designed.

The LHC itself is a ring 17 miles (27km) in circumference, buried up to 100m (330ft) underground, through which streams of protons will be bent by the world’s most powerful magnets and smashed into each other at close to the speed of light.

The new cavern, which will house the Atlas detector for tracking the Higgs and other particles, is 40m (130ft) deep, 55m (180ft) long and 35m (115ft) wide.

However, the proton beam that runs through both devices measures just 10 microns in diameter: less than a quarter of the thickness of the average human hair. Roger Cashmore, a British physicist and Cern’s director of research, said: “It is an astonishing feat of engineering. The consultants were on the verge of saying it was impossible to build. But the Atlas cavern is finished, the biggest of its kind in the world, and these experiments are going to tell us whether we’re right about the Universe.”

The current best guide to the nature of the Universe is the Standard Model, an elegant theory that describes how most particles and forces interact. The Higgs boson is its missing keystone: without it, there is no good explanation for why matter has mass and therefore exists.

According to the theory, the Universe is permeated by a field of Higgs bosons, which consist of mass but very little else. As particles move through the field, they interact with it like a ball dropped into a tub of treacle, getting slower, stickier and heavier. Their ultimate mass depends on the strength of the interaction.

Though mathematics predicts its existence, the Higgs boson has never been detected. It is so heavy that the biggest atom-smashers, Cern’s Large Electron-Positron collider (LEP) and the Tevatron at Fermilab in Illinois, have been unable to generate the high energy collisions needed to reveal it, although they have found hints that it is probably there. This is where the LHC comes in. It is 70 times as powerful as the LEP and seven times stronger than the Tevatron, covering all the energy values at which the Higgs might exist. If it is there, it will find it.

What is more, if the “God particle” proves to be a false deity, the LHC will unlock the secret of what is out there instead. “If it doesn’t find the Higgs, it will find what substitutes for it,” Dr Cashmore said.

Jim Virdee, Professor of Physics at Imperial College, London, and a leading Cern researcher, said: “There has to be something else, beyond what we have found already, that explains mass. We believe it’s the Higgs, but Nature may be smarter than us. Either way, the results will tell us what is the right road.”

The atom-smasher will accelerate protons so close to the speed of light that they become 7,000 times heavier than normal. The beams are bent into a circle by superconducting magnets, cooled by liquid helium at -271.4C, almost a degree colder than outer space.

When the protons collide, they are destroyed in a huge burst of energy. This energy coalesces into very heavy particles, one of which scientists hope will be the Higgs.

As the boson is unstable, it will quickly decay, scattering a characteristic signature of smaller particles and energy. These will be picked up by the LHC’s eyes — the Atlas and a sister detector — which surround the collision points.

The detectors, which stand 22m (72ft) and 15m (49ft) tall respectively, are “giant microscopes” built like onions, with several layers of instruments that track particles and measure energy.

The experiments will generate enormous quantities of data, much of it unwanted. “Colliding two protons is like colliding two oranges,” Dr Lyn Evans, director of the LHC project, said. “You’ll occasionally get a collision between two pips, the interesting bits, but you’ll get a lot of pulp. We need to reject an enormous amount of data to pick out the important bits.” Professor Virdee said that the data generated in one second was the equivalent of what all the world’s telecommunications generated in one year.

Even if this wealth of information proves the existence of the Higgs boson, the LHC will continue to serve scientific knowledge for decades.

“Let’s say we have the Higgs,” Dr Cashmore said. “I’d feel warm and content for a few microseconds, then I’d be asking new questions. Why does it affect different particles in different ways? “It would be spectacularly good to find it — I’m not trying to knock it — but it will pose a whole new set of problems. If we are an inquisitive society, these are the things we ought to be doing."

I think AndrewC is trying to understand the notion that 2 particles are now farther away, but neither of them moved.

...

Inflation is one of those things that seems like happened, because it's consistent with known observations.

To say nothing has moved is clearly ludicrous. Any force calculation that I know of will have changed. And you can't call out the dreaded relativistic corrections, because you have stated the objects are not moving.

Next, I know of no observation of anything traveling faster than the speed of light in vacuo. And the paper openly states that velocities v > c are possible since they cannot be observed(essentially). That statement puts inflation in the category of faith and not science. Thus a person holding to inflation should never complain about any other introduction of faith into science.

Correct me if I am wrong, but I believe the correct term to characterize those "unreachable" regions of the Universe is that they are "causally disconnected" from ours, and ours from them.

I'm not the one you asked, and I'm probably not the one to answer, but to me the expression "causally disconnected" implies that there was previously a causal connection. Such could be the case for something that has moved beyond our observational horizon. But I'm thinking of a scenario like a universe of multiple big-bang universes, with each one functioning as an oscillating black hole, banging and collapsing, eternally. The light from each would be forever trapped, and each system would be "causally un-connected" from the others. (Not dis-connected.) If the professional physics community makes no such distinction, fine. I'm still not running off to join the TimeCube guy.

To say nothing has moved is clearly ludicrous.

Actually that was the first reaction that I had along with others in the class. Once you get past the notion that space is nothing and matter fills it up, you get closer to the concept. One way to look at it is that space is something that is everywhere. It can be stretched and pulled. Then matter precipitates out of it when it is sufficinetly distorted.

Unfortunately we're stuck with inflation until somebody finds something new to look at.

Once you get past the notion that space is nothing and matter fills it up, you get closer to the concept.

Then matter precipitates out of it when it is sufficinetly distorted.

Again, 2 != 1.

And the paper openly states that velocities v > c are possible since they cannot be observed(essentially). That statement puts inflation in the category of faith and not science.

That's O.J. jury logic. Nobody on the jury saw O.J. do it, so no amount of evidence will ever be sufficient to pronounce a guilty verdict. The glove, the shoes, the CMBR were all planted by "the man" to fool us.

And again, 1 + (-1) = 0.

That somehow negates 2 != 1? We are not speaking of something moving then moving back. Something moved. If R has changed the forces associated with R have changed. That is somewhat related to how we can tell that R has changed.

Nobody on the jury saw O.J. do it, so no amount of evidence will ever be sufficient to pronounce a guilty verdict.

Yeah right. You would have the jury convict O.J. due to these words.

I know that there is concrete evidence that O.J. murdered Nicole but it became disconnected from causality so you cannot see it. Convict him anyway.

Or have them acquit O.J. due to these words.

O.J. could not have been in the home that night. He was in Europe. His corroborating witnesses have been taken by Martians and will be eternally unavailable. Release O.J.

Great theater, bad science.

INTERESTED PARTIES MUST READ THIS…
Two questions/issues must give one pause:

1) Stephen Hawking and Higgs have traded words publicly over whether it is even possible to "see"/measure Higgs bosons. Hawking has previously bet – and won -- that we CAN'T with our current technology.

2) Recent studies at Lawrence Berkeley National Laboratory have shown (although errors are always possible in this field), that a Standard Model assumption about the predicted energy/mass of the Higgs Boson is empirically WRONG. Don’t listen to this old physics student, read the articles at the attached URLs (the lbl.gov article is the most important).

http://www.lbl.gov/Science-Articles/Archive/Phys-lose-lose.html
http://millennium-debate.org/ind3sept023.htm

CMBR didn't exist, you'd have a point.

It is no surprise that something that cannot be demonstrated solves something for which it was invoked. The CMBR existed prior to inflation. Inflation was created to explain properties of CMBR, so it is not unexpected that the properties of CMBR are consonant with the explanation. But, matter attaining a velocity of the absolute universal speed limit and then exceeding that limit is not an expected consequence. However, that consequence is hand-waved away.

That statement puts inflation in the category of faith and not science. Thus a person holding to inflation should never complain about any other introduction of faith into science.

You're conflating scientific theory with faith, therefore your conclusion is wrong.

The CMBR existed prior to inflation.

Irrelevant. The CMBR is a general feature of Big Bang models. What did not exist prior to the Inflation model was the incredibly detailed anisotropy power spectrum:

The curve is the theoretical prediction, and the data are from the WMAP probe, which published its results in February. Oh, and the polarization of the background is similarly well-predicted.

Inflation was created to explain properties of CMBR

Any Big Bang model predicts a CMBR of some kind; the properties of the CMBR that Inflation best explains weren't even known at the time (see above). Inflation was proposed to solve the horizon problem (why is the temperature of the universe so uniform), the flatness problem (why do the angles of large triangles sum to 180 degrees) and the homogeneity problem (why are there no--or so few--magnetic monopoles).

You're conflating scientific theory with faith, therefore your conclusion is wrong.

No. I'm stating that accepting something without any evidence especially when it is counter to other accepted "facts" is faith.

But Inflation doesn't fall into that category.

It does when it invokes a disconnect from causality to explain matter achieving then exceeding the speed of light in vacuum limit.

But that isn't what Inflation invokes. It's space that "expands faster than light", not matter. The cosmic speed limit doesn't apply to space. If you'd been sitting on some of that matter, you'd have felt no acceleration whatsoever.

It's space that "expands faster than light", not matter.

But space without matter or energy is just space and does not need to be disconnected from causality. The disconnection was needed for a reason.

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