Quantum Theory

i dont see how any device we have today could do such a feat, everything that we arent experimenting with and use in our technology is too big of particles to detect such small amounts of mass, so how do they detect thge collisions scattered particles after the event? Thanks.

in all the diagrams ive seen with photons involved, it shows that photons are spherical shapes, is this just because of the fact that thats the easiest way to show it?, or are they really like that? if so, then why? photons have no mass, right? wrong? either way, i dont think that theyed come out spherical, theyed just be whatever wouldnt they? nothing pushing against them, like bubbles, is there? or maybe the speed that there going would stretch them out in a sense, so there more cyndrical. any one know?

Wouldnt smashing particles into atoms instigate nuclear fission? Obviously not, AFAIK no particle colliders have gone a-bomb, so evidently im wrong or there is something they do to prevent it. Any help?

Well, we know matter can be divided until you reach its fundamental particles (electrons, quarks, whatever), and QM tells us that this is so for energy as well (photons). But then some go further and claim that QM shows spacetime to be composed of fundamental units as well. Usually, what they are refering to are the Planck units (like the Planck length, Planck time, etc.) - those measures of space and time for which we cannot measure anything smaller. But is this warranted? Is it warranted to say that these smallest units of measurement are 'particles' of space and time, that there is no amount of space or duration of time smaller than these amounts? Or is it just…

They say that in order to measure or detect an electron, a photon must be fired at it. But can an electron be measured or detected if the detection device simply receives a photon it spontaneously emits? I have a follow up question about this.

I want you to inform me about the great physicists' works. I'm looking for any collected papers or works of physicists such as Broglie, Pauli, Heiseinberg on the internet sources; but I couldn't find any satisfactory site or document except for Schrodinger, Einstein, Bohr and Rutherford. please help me and share your documnents related with me.

Is it possible to have a shadow effect within a crystal latice at a atomic level ? ie can one atom be shielded from the effects of photons by a intervening atom.

spin up and spin down. which corresponds to paramagnetism and which to diamagnetism. and is there a more intuitive way to refer to the spin state of an electron than 'up' or 'down'?

This experiment requires a 'perfectly separated box' - that there is no interactions with its outside. It can be realized by spatial separation - using that interactions can travel with at most speed of light. So imagine we've found a planet let say a light year from us - that we've analyzed it, can simulate it as perfectly as possible. We can send some 'reports' between us and this planet with a speed of light - they are received a year after sending. Let there be a cat which life depends on a spontaneous emission - we will get a report a year later, so before that we will be out of causal cone of this episode - from our perspective - this cat is in entangled state…

In the original EPR article, it's written, "If, [...], we can predict [...]" I'm not a native english speaker, but shouldn't it be written "If, [...], we COULD predict [...]" ?? "can" in this case is like a grammatical error ? Or sound that negative from the onset and the present version could be, at the limit right...since we still don't know if we can predict or not ?? Thanks in advance

Can anyone please settle an ongoing dispute..... Is fluorescence a form of scattering like Raman or not ?

Starting from [math]E^2=m^2c^4+p^2c^2[/math], then a matrix-type root we get Dirac equation. But here, the term pc is a kinetic term, but not for massive particle, i.e. pc is only for massless. Is it that this equation rules a field with a massive (mc^2) and a massless parts ?

What is vacuum aka space supposed to be made of? Since vacuum has properties such as impedance, permiability and permittivity, is it considered a media?

Has the value of the elementary charge of a particle decreased over time? I'm curious why 'e' is lower than the Planck charge value and if the Planck charge value ever shows up ever in nature. Thanks, Greg

Quantum electrodynamics (relativistic quantum field theory) is believed to be better approximation of physics than quantum mechanics - for example because it allows for extremely accurate predictions of Lamb shift. http://en.wikipedia.org/wiki/Quantum_electrodynamics One of formulations of field theories is due to Lagrangian density - physics finds the field which minimizes integral of this density over four dimensional space - so called action. Now using Euler-Lagrange equations, we can find necessity condition for such minimization, which is in form of time evolution - we get 'evolving 3D' picture. These equations are completely deterministic - we don't have a…

Can an orbiting electron/positron ensemble be in an excited spin-2 state? Is orbital AM still quantized in units of [math]\hbar[/math]? It seems the latter answer is yes, as you could say the particles orbit about a common center, so the problem is not so different from a massive atomic center.

What is the shape of the Planck volume? According to: http://en.wikipedia.org/wiki/Planck_units ... The Planck volume is just Planck_Length^3 . Does this imply the Planck volume is cubical?

If the new train of thought places limits on time travel ie time decay in one dimension would it not hold water that transiting through time itself would place us in another dimension were time decay at a sub atomic level would be relative to that inertial time frame and allow further travel by opening up multiple wormholes and passing through time with due respect to time decay . In other words allowing a passage through time from one I.T.R. point to another once again being aware of time decay .We would end up leap frogging through space by multiple wormholes being opened in each ITR. The only problem this would present is taking the teletransportation equipment t…

spin of electron=s=1/2 S=(h/2π)*√s(s+1) μs=S*gs*q/2m gs=2 l=0 or 1 or 2 ... up to n-1 L=(h/2π)*√l(l+1) μL=L*gL*q/2m gL=1 net magnetic moment of electron in subshell l = μs + μL is this correct? Merged post follows: Consecutive posts mergedalso do the 2 components have the same sign? is the sum greater than or less than the magnetic moment due to spin alone?

How does 'Squeezed Vacuum' technology aid in the creation of quantum computing networks..................... Merged post follows: Consecutive posts mergedOk...so how does the technology quoted as being called 'Squeezed Vacuum' technology applied in this http://www.sciencedaily.com/releases/2009/02/090203130708.htm help provide a means for quantum computing..................... How could a better vacuum make for better changes in chiral states and create say a quantum comparator?

i was just reading up on superdense matter in this article: http://arxiv.org/abs/0705.2708v2 and this passage got me wondering "There has been much recent progress in our understanding of quark matter, culminating in the discovery that if quark matter exists it ought to be in a color superconducting state [22, 23, 24, 25]. This is made possible by the strong interaction among the quarks which is very attractive in some channels. Pairs of quarks are thus expected to form Cooper pairs very readily. Since pairs of quarks cannot be color-neutral, the resulting condensate will break the local color symmetry and form what is called a color superconductor." when …

While playing with Planck constants I noticed the following: The electric constant can be figured from: ((Tp^2 * Qp^2) / (Mp * Lp^3)) * (1/(4*pi)) Where, Tp = Planck Time , Qp = Planck Charge, Mp = Planck Mass, Lp = Planck Length And the magnetic constant can be determined with: ((Mp * Lp) / (Qp^2)) * (4*pi) Anyone know why the "4 pi" pops up like this?

I finished reading Sleator's The Last Universe and wondered if that could be really experienced or created. Such a thing would be in itself a uncertainty. But my main question is this. Could a park manifest itself in a way that could allow flowers from a different climate could grow?

I'm not a physicist, but it seems to me that something is left out of the double slit experiment. When a series of electrons are sent toward one slit while two slits are open they build up an interference pattern similar to what one would expect from a wave passing through both slits. The problem is, when you drop something in the water to create a wave, it comes from overhead, or perpendicular to the surface of the water. I wonder if a corner double slit experiment has been carried out whereby two "walls" meet at 90 degrees and electrons are sent through one of the slits. Does an intereference pattern appear? This would indicate that the wave is spherical. But i…

the aim of this thread is to gather essential information from all quantum gravity-related threads into one, to get some focus Links to other SFN threads will be provided, and links to outside sources Smolin: How far are we from the quantum theory of gravity? http://arxiv.org/abs/hep-th/0303185 Rovelli: Quantum Gravity Cambridge Press 2004 http://www.cpt.univ-mrs.fr/~rovelli/rovelli.html Smolin: Invitation to Loop Quantum Gravity http://arxiv.org/hep-th/0408048 Ashtekar Lewandowski: Background Independent Quantum Gravity; a Status Report http://arxiv.org/abs/gr-qc/0404018 Smolin: Scientific Alternatives to the Anthropic Principle http://arxiv.org…