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"Higgs Boson partices - guaranteed to satisfy! Need mass in your objects? Get some Higg Bosons!" "The Higgs Boson particles are SOLD WITH THE JAR! You may not be able to SEE the Higgs Boson particles unless you use a large hadron collider." "Q: Since it is, after all, the god particle; can you observe closely and tell use what religion it is?"

Galactic Cosmic Radiation consisting of high-energy, high-charged (HZE) particles poses a significant threat to future astronauts in deep space. Aside from cancer, concerns have been raised about late degenerative risks, including effects on the brain. In this study we examined the effects of 56Fe particle irradiation in an APP/PS1 mouse model of Alzheimer's disease (AD). We demonstrated 6 months after exposure to 10 and 100 cGy 56Fe radiation at 1 GeV/µ, that APP/PS1 mice show decreased cognitive abilities measured by contextual fear conditioning and novel object recognition tests. Furthermore, in male mice we saw acceleration of Aβ plaque pathology using Congo red and 6E10 staining, which was further confirmed by ELISA measures of Aβ isoforms. Increases were not due to higher levels of amyloid precursor protein (APP) or increased cleavage as measured by levels of the β C-terminal fragment of APP. Additionally, we saw no change in microglial activation levels judging by CD68 and Iba-1 immunoreactivities in and around Aβ plaques or insulin degrading enzyme, which has been shown to degrade Aβ. However, immunohistochemical analysis of ICAM-1 showed evidence of endothelial activation after 100 cGy irradiation in male mice, suggesting possible alterations in Aβ trafficking through the blood brain barrier as a possible cause of plaque increase. Overall, our results show for the first time that HZE particle radiation can increase Aβ plaque pathology in an APP/PS1 mouse model of AD.

"At least two other particles could be masquerading as the God particle, according to a new analysis of the data from CERN" As I said.. the press always tends to exaggerate...

have to be carefull this article is really badly written. Teleportation is not some matter that disapear from somewhere to reappear somewhere else... Usually we talk about entangled particles (by essence quantum theory is non-local), and teleportation means that if you force (with a measurement) one particle to take a particular quantum state then the other one will have the same quantum state. There it seems that the same could be done with a quantum field, which is the second quantization of the quantum theory: the state of a quantum field can contain a mixture of n-particles states (meaning that the number of particles is not defined, only the mean value). If you measure the number of particle then you force the quantum field to "choose" a particular quantum state (which can be the vacuum). Teleportation means that you will have exactly the same measure on another quantum field, which is somehow intricated to your first one.

The first complete theory of how plasmons produce "hot carriers" has been developed by researchers in the US. The new model could help make this process of producing carriers more efficient, which would be good news for enhancing solar-energy conversion in photovoltaic devices.

I did not read the paper but what is further down written in the article, does not give much hope that this actually gives much more insight than what we had nor that it could be used in any way to improve current PV cells soon: e.g. "To fully exploit these carriers for such applications, researchers need to understand the physical processes behind plasmon-induced hot-carrier generation. Nordlander's team has now developed a simple model that describes how plasmons produce hot carriers in spherical silver nanoparticles and nanoshells. The model describes the conduction electrons in the metal as free particles and then analyses how plasmons excite hot carriers using Fermi's golden rule - a way to calculate how a quantum system transitions from one state into another following a perturbation. The model allows the researchers to calculate how many hot carriers are produced as a function of the light frequency used to excite the metal, as well as the rate at which they are produced. The spectral profile obtained is, to all intents and purposes, the "plasmonic spectrum" of the material. Particle size and hot-carrier lifetimes "Our analyses reveal that particle size and hot-carrier lifetimes are central for determining both the production rate and the energies of the hot carriers," says Nordlander. "Larger particles and shorter lifetimes produce more carriers with lower energies and smaller particles produce fewer carriers, but with higher energies."

what an interesting personality ... very symathetic Peter Higgs, the British physicist who gave his name to the Higgs boson, believes no university would employ him in today's academic system because he would not be considered "productive" enough.

The emeritus professor at Edinburgh University, who says he has never sent an email, browsed the internet or even made a mobile phone call, published fewer than 10 papers after his groundbreaking work, which identified the mechanism by which subatomic material acquires mass, was published in 1964.

He doubts a similar breakthrough could be achieved in today's academic culture, because of the expectations on academics to collaborate and keep churning out papers. He said: "It's difficult to imagine how I would ever have enough peace and quiet in the present sort of climate to do what I did in 1964."

Speaking to the Guardian en route to Stockholm to receive the 2013 Nobel prize for science, Higgs, 84, said he would almost certainly have been sacked had he not been nominated for the Nobel in 1980.

Edinburgh University's authorities then took the view, he later learned, that he "might get a Nobel prize - and if he doesn't we can always get rid of him".

Higgs said he became "an embarrassment to the department when they did research assessment exercises". A message would go around the department saying: "Please give a list of your recent publications." Higgs said: "I would send back a statement: 'None.' "

By the time he retired in 1996, he was uncomfortable with the new academic culture. "After I retired it was quite a long time before I went back to my department. I thought I was well out of it. It wasn't my way of doing things any more. Today I wouldn't get an academic job. It's as simple as that. I don't think I would be regarded as productive enough."

Higgs revealed that his career had also been jeopardised by his disagreements in the 1960s and 7

And the follow up by Nobel prize winner Randy Schekman http://www.theguardian.com/science/2013/dec/09/nobel-winner-boycott-science-journals

interesting one - Luzi will like it :-)

"Researchers hope the minute particles are from the asteroid"

Here is the tractor beam I mentioned from fridays science coffee. At the moment its used for microscopic particles only. This could be looked into to see if it could be scaled up to deflect particles in space

Theoretized 80 years ago was Breit-Wheeler pair production in which two photons result in an electron-positron pair (via a virtual electron). It is a relatively simple Feynmann diagram, but the problem is/was how to produce in practice a high energy photon-photon collider... The collider experiment that the scientists have proposed involves two key steps. First, the scientists would use an extremely powerful high-intensity laser to speed up electrons to just below the speed of light. They would then fire these electrons into a slab of gold to create a beam of photons a billion times more energetic than visible light. The next stage of the experiment involves a tiny gold can called a hohlraum (German for 'empty room'). Scientists would fire a high-energy laser at the inner surface of this gold can, to create a thermal radiation field, generating light similar to the light emitted by stars. They would then direct the photon beam from the first stage of the experiment through the centre of the can, causing the photons from the two sources to collide and form electrons and positrons. It would then be possible to detect the formation of the electrons and positrons when they exited the can. Now this is a good experiment... :)

True, but isnt it E2=(pc)^2 + (m0c^2)^2 such that for photons E\propto{pc} and for mass E\propto{mc^2}. I agree it will take a lot of energy, but this assumes that that wont be the problem at least. The question therefore is whether the mass flow of the photon rocket (fuel consumed to create photons, eg fission/fusion) is higher/lower than the mass flow for e-p creation. You are probably right that the low e-p cross-section will favour direct use of photons to create low thrust for long periods of time, but with significant power available the ISP might be higher for e-p pair creation.

In essence the equation tells you that for photons with zero rest mass m0 all the energy will be converted to momentum of the particles. If you want to accelerate e-p then you first spend part of the energy on creating them (~511 keV each) and you can only use the remaining energy to accelerate them. In this case the equation gives you a lower particle momentum which leads to lower thrust (even when assuming 100% acceleration efficiency). ISP is a tricky concept in this case because there are different definitions which clash in the relativistic context (due to the concept of mass flow). R. Tinder gets to a I_SP = c (speed of light) for a photon rocket (using the relativistic mass of the photons) which is the maximum possible relativistic I_SP: http://goo.gl/Zz5gyC .

Just getting a particle up to near the speed of light isn't good enough for today's physics. To properly unravel the fundamentals of the universe, particles have to be smashed together with enormous force. And two Stanford researchers have just devised a laser-based method that imparts ten times the power of traditional methods at a fraction of the cost.

The problem is that the light cone angle has a limit - all particles with high momentum (mass x velocity) generate light cones with the same angle. Hence, these particles are indistinguishable. Now Chalmers researcher Philippe Tassin and his colleagues at the Free University of Brussels have designed a material that manipulates the Cherenkov cone so that also particles with high momentum get a distinct light cone angle too. The work is on the cover of this week's issue of the journal Physical Review Letters ("Controlling Cherenkov Radiation with Transformation-Optical Metamaterials").

"... scientists at the Technical University of Delft in the Netherlands yesterday published their findings that they have indeed found the Majorana particle. The announcement on the university website provides both a summary of the ..." Also see: http://tudelft.nl/en/current/latest-news/article/detail/nanowetenschappers-vinden-langgezocht-majorana-deeltje/

Redshift in this model is partially produced by a change in the masses of elementary particles (and atoms)

It should not be impossible to verify a change in mass(es) over time. For example the electron cyclotron frequency scales ~e/m while the Hydrogen emission frequencies scale with ~m*e^4. Using multiple relationships like that which can be easily and accurately measured an increase in the mass of fundamental particles should - in principle - be detectable (even if the mass of the earth increases at the same time changing the relativistic reference frame).

The Watt balance and a definition using the Planck's constant seems to do the trick and is currently being discussed. Would the electron charge not be problematic as it is related to Coulombs which depends on Amperes which is defined by Newtons which hence depends back on the mass again?

Can we have one?

They say they create 2 GeV electrons in a very small setup. However the laser they use is more than 10 meters in length. Still a really nice result.

Compared to a 27km circumference this is major achievement and it is indeed already foreseen that future colliders will include this technology as beam fillers and pre-accelerators at some point. The technique is quite elegant and a lot more energy efficient. Nevertheless, there are also thoughts that future particle colliders might actually go towards space and study collisions orginating from extremely energetic cosmic particles

Interesting... however to me it looks like they have only shifted the problem... instead of looking for WIMPS now we look for X and Y and Phi...

Some bacteria can influence the weather. Up high in the sky where clouds form, water droplets condense and ice crystal grow around tiny particles. Typically these particles are dust, pollen, or even soot from a wildfire. But recently scientists have begun to realize that some of these little particles are alive - they are bacteria evolved to create ice or water droplets around themselves. old but might be worth a discussion

"The experiments involve an oil droplet that bounces along the surface of a liquid. The droplet gently sloshes the liquid with every bounce. At the same time, ripples from past bounces affect its course. The droplet's interaction with its own ripples, which form what's known as a pilot wave, causes it to exhibit behaviors previously thought to be peculiar to elementary particles - including behaviors seen as evidence that these particles are spread through space like waves, without any specific location, until they are measured." Pilot-wave theory reresurrected. Maybe something for the next "fundamental" :P physics RF?

And for the next 'Experimental Physics Stagiaire' position why not try to do "Unpredictable Tunneling of a Classical Wave-Particle Association" http://stilton.tnw.utwente.nl/people/eddi/Papers/PhysRevLett_TUNNEL.pdf, there are some rumors online that the results of Yves Couder Experiments can be reproduced with simple DIY vibrating tables! It is very funny to see the videos of the MIT's replication of this experiment (with lightening legends for those who are uncomfortable with the concepts involved https://www.youtube.com/watch?v=YF5iHQMjcsM)

An experiment at the Fermi National Accelerator Laboratory near Chicago has detected far more electron neutrinos than predicted - a possible harbinger of a revolutionary new elementary particle called the sterile neutrino, though many physicists remain skeptical.

With self-assembly guiding the steps and synchronization providing the rhythm, a new class of materials forms dynamic, moving structures in an intricate dance. Researchers have demonstrated tiny spheres that synchronize their movements as they self-assemble into a spinning microtube.

This is quite similar to the following paper. Here they show how tiny variations of particle parameters can produce clearly distinct structures: Thermal and Athermal Swarms of Self-Propelled Particles --> http://arxiv.org/abs/1201.0180