CERN Large Hadron Collider – Big Science

Thanks to Jeremy for pointing out to me a photo feature on the LHC at CERN. Some really brilliant pictures of truly Big Science getting built.

View of the CMS detector at the end of 2007 (Maximillien Brice, (c) CERN)

View of the CMS detector at the end of 2007 (Maximillien Brice, (c) CERN)

Of course, if you’re worried about this causing the world to end it’s probably worth reading the info they put out in 2003, which simply points out that the Earth will have seen this (and much more) before:

The Large Hadron Collider (LHC) can achieve an energy that no other particle accelerators have reached before, but Nature routinely produces higher energies in cosmic-ray collisions. […] Whatever the LHC will do, Nature has already done many times over during the lifetime of the Earth and other astronomical bodies.

To put things into proportion:

Speculations about microscopic black holes at the LHC refer to particles produced in the collisions of pairs of protons, each of which has an energy comparable to that of a mosquito in flight.

So you can put your brown paper bags away now.. 🙂

Dark Energy Stars, a Replacement for Black Holes ?

Here’s an interesting thought, what if black holes didn’t exist but instead a collapsing star underwent a quantum critical phase change, turning into a rather peculiar, but QM compliant, object ?

This is what two physicists from LANL believe could be happening.

The report in New Scientist says:

[…] Chapline and Laughlin found some answers in an unrelated phenomenon: the bizarre behaviour of superconducting crystals as they go through something called “quantum critical phase transition” (New Scientist, 28 January, p 40). During this transition, the spin of the electrons in the crystals is predicted to fluctuate wildly, but this prediction is not borne out by observation. Instead, the fluctuations appear to slow down, and even become still, as if time itself has slowed down.

“That was when we had our epiphany,” Chapline says. He and Laughlin realised that if a quantum critical phase transition happened on the surface of a star, it would slow down time and the surface would behave just like a black hole’s event horizon. Quantum mechanics would not be violated because in this scenario time would never freeze entirely. “We start with effects actually seen in the lab, which I think gives it more credibility than black holes,” says Chapline.

With this idea in mind, they – along with Emil Mottola at the Los Alamos National Laboratory in New Mexico, Pawel Mazur of the University of South Carolina in Columbia and colleagues – analysed the collapse of massive stars in a way that did not allow any violation of quantum mechanics. Sure enough, in place of black holes their analysis predicts a phase transition that creates a thin quantum critical shell. The size of this shell is determined by the star’s mass and, crucially, does not contain a space-time singularity. Instead, the shell contains a vacuum, just like the energy-containing vacuum of free space. As the star’s mass collapses through the shell, it is converted to energy that contributes to the energy of the vacuum.

The team’s calculations show that the vacuum energy inside the shell has a powerful anti-gravity effect, just like the dark energy that appears to be causing the expansion of the universe to accelerate. Chapline has dubbed the objects produced this way “dark energy stars”.

A really intriguing possibility and one that, they believe, could be verified or disproved in 5-10 years.

Schrödingers Cat, Observers and the Participatory Anthropic Principle

Following on from a posting on Rich Boakes blog I left the following comment which struck me as interesting enough to be a post of its own right here.

Rich posits the question of what would happen if Schrödingers Cat had mirrors in its own box, would it collapse its own waveform ?

My guess is not, simply because it will never be capable of observing the moment of its own death as if it were able to it would, by definition, still be alive. However, I then brought up the following..
Strangely enough, I’ve been thinking about this problem from a different viewpoint – if the box with the dead/live cat in is opened by an observer inside a locked room who then dies before being able to pass on the information does the waveform collapse when he sees it and stay collapsed, or does it not collapse from the point of view of an observer outside the room?

I was wondering if it collapsed and then uncollapsed, but I suspect from a QM point of view it’s likely to be one of the two former cases – and my gut reaction is that it would be the latter..

So again it begs the question of who/what exactly constitutes an observer ? There is the participatory anthropic principle that says that conscious life is necessary to the universe in order for the collapse of QM waveforms to occur, but I think that’s a particularly long straw to grasp..

Non-Running Quantum Program Gives Answer

From the “my brain hurts” department..

New Scientist magazine is reporting that:

[..] researchers from the University of Illinois at Urbana-Champaign have improved on the original design and built a non-running quantum computer that really works

Yes, you read that correctly.. they’ve built a quantum computer that doesn’t do anything but provides the correct answer.

This is from something called the Zeno Effect that has been exploited here to allow a photon to be influenced on a quantum level with a non-operational quantum computing program, but (through the constant measurement inherent in the Zeno Effect) not be allowed to actually execute the program. Through this influence the answer appears, even though you’ve never run the program.

One of the developers said:

“It is very bizarre that you know your computer has not run but you also know what the answer is,”

and

“A non-running computer produces fewer errors,”

I couldn’t put it better myself! 😎