Acoustic Hawking Radiation
With an acoustic horizon (a.k.a. "sonic horizon"), this ordered set of definitions breaks down: events behind an acoustic horizon can modify the effective horizon position and allow information to escape from a horizon-bounded region. This results in acoustic horizons following a different set of rules to gravitational horizons under general relativity:
So here in lies another idea for Clifford and the drama created by the involuntary presence that can make good sane people cry. These onion people are working in another dimension? Some might call it wizardary, only if they did not understand the science and the geometry behind the curvature parameters. It is a hyperphysics mode to which those who has studied would know that Kaku was very kind in bringing common sense to what our ole Geometers had to say in a long line of historical perpective.
I will bring perspective to quantum geometry shortly in another blog entry.
Atlas Experiment
ATLAS (A Toroidal LHC ApparatuS) is one of the five particle detector experiments (ALICE, ATLAS, CMS, TOTEM, and LHCb) being constructed at the Large Hadron Collider, a new particle accelerator at CERN in Switzerland. It will be 45 meters long, 25 meters in diameter, and will weigh about 7,000 tons. The project involves roughly 2,000 scientists and engineers at 151 institutions in 34 countries. The construction is scheduled to be completed in 2007. The experiment is expected to measure phenomena that involve highly massive particles which were not measurable using earlier lower-energy accelerators and might shed light on new theories of particle physics beyond the Standard Model.
Well most will not comprehend what I am saying, and nor did I, until I came across and looked for a better understanding of what signatures mean to a physicist. Who is working on the Cern project, and the detectors methods for consideration. What the term onion word might spark, as I look back and seen that a previous comment had been planted for another day like today.
How vast indeed this project, that out of it such collision processes can be accounted for in the way a onion can be peeled, layer upon layer, just like our Atlas Detector is. In the way it had been design for those particle detection methods. There are enough links here to satisfy the inquring mind, as to what these layers are, and what they are designated for in that detection process.
Frontiers and Mega Magnets
Like all the detectors used in today’s collider experiments, the ATLAS apparatus is huge – in order to catch the myriad of particles produced when protons smash into each other. It consists of a series of detecting devices in an onion-ring arrangement around the central tube in which the proton beams collide. Each detector does a different job, measuring the positions and energies of the different particles produced – electrons, photons, muons etc. The momenta of the charged particles are measured from the curvature of their trajectories in a magnetic field provided by superconducting magnets. The volume and strength of magnetic field needed are not achievable with conventional magnets.
Now I highlighted the statement in bold because it means something to me more then just the way we would look at, but what these curvatures can mean in comparative modes of geometrical expressions.
Now as a lay person, the curvature parameters that were developed from the understanding of the Friedman equations, help me to see the issue of hyperbolic/ spherical as real cosmological issues, but way down at the quantum level, what is this showing us?
The Friedmann equation which models the expanding universe has a parameter k called the curvature parameter which is indicative of the rate of expansion and whether or not that expansion rate is increasing or decreasing. If k=0 then the density is equal to a critical value at which the universe will expand forever at a decreasing rate. This is often referred to as the Einstein-de Sitter universe in recognition of their work in modeling it. This k=0 condition can be used to express the critical density in terms of the present value of the Hubble parameter.
For k>0 the density is high enough that the gravitational attraction will eventually stop the expansion and it will collapse backward to a "big crunch". This kind of universe is described as being a closed universe, or a gravitationally bound universe. For k<0 the universe expands forever, there not being sufficient density for gravitational attraction to stop the expansion.
So the very idea of the expansion and contraction, holds on to my mind, and this dynamical process is very revealling in our point of view. I can't but help feel this GR sense in momentum, as objects and articles are held to the mass impression of the spacetime fabric.
The Magnet System
The ATLAS detector uses two large magnet systems to bend charged particles so that their momenta can be measured. This bending is due to the Lorentz force, which is proportional to velocity. Since all particles produced in the LHC's proton collisions will be traveling at very close to the speed of light, the force on particles of different momenta is equal. (In the theory of relativity, momentum is not proportional to velocity at such speeds.) Thus high-momentum particles will curve very little, while low-momentum particles will curve significantly; the amount of curvature can be quantified and the particle momentum can be determined from this value.
So by quoting here and representing curvature parameters on a cosmological scale, it was not to hard to figure how signatures would be revealled.