DARK ENERGY - The Chameleon Particle

By TPMCafe.com

Is the 'Chameleon Particle' dark energy...? Bonus news at the bottom.

There is a theory about dark energy that is gaining some traction. Its called the Chameleon Particle theory and it states that maybe dark energy is actually a particle that is hard to find because of its strange properties. When it combines with a photon (light) the combined particle changes its mass depending on its surroundings and makes it hard to find. Hence the monicker.

This is how wiki describes it:

The "chameleon" is a postulated scalar particle with a non-linear self-interaction which gives the particle an effective mass that depends on its environment: the presence of other fields. It would have a small mass in much of intergalactic space, but a large mass in terrestrial experiments, making it difficult to detect. The chameleon is a possible candidate for dark energy and dark matter, and may contribute to cosmic inflation.

Now the theory has some promise:

By comparing light emitted across a range of frequencies from the luminous centres of 77 active galaxies, Douglas Shaw at Queen Mary University of London and his colleagues have found what they call "good evidence" that some photons have gone missing in transit.

If the light is missing, they theorize, then maybe it changed into something else.

By itself, the findings dont show more than an unanswered question but if the theory is true the particle should be detectable. Because they would be able to change their mass, they should get heavier as they try to pass through a special chamber and thus get trapped. Then we could finally "see" them.

Chameleons can be confined in hollow containers because their mass increases rapidly as they penetrate the container wall, causing them to reflect. One strategy to search experimentally for chameleons is to direct photons into a cavity, confining the chameleons produced, and then to switch off the light source. Chameleons would be indicated by the presence of an afterglow as they decay back into photons

So now the first round of lab results are in. How'd it go? Not so good.

While they didn't find a signal in this round of work, the results did put constraints on some of the properties of the evasive particle, including its mass and its coupling to photons.

But the latest observations are reviving hope

...the group's analysis appears to get a boost from an independent study into an unusually high flux of high-energy photons spotted by the MAGIC telescope on La Palma and the VERITAS telescope in Arizona. The results have perplexed astronomers because very high-energy photons should be kept from reaching Earth by interactions with the cosmic microwave background radiation.

Now, they want to run the tests again in light of the latest observations.

The GammeV group is now preparing to test for chameleons in that "interesting range", says Weltman.

Can anybody spare a dime?

Stay Tuned...