Quantum Theory

Hopefully I can prevent this from coming out as an assorted mishmash of completely non-technical gibberish. I realize it's inherently foolish to attempt to explore physics from a purely conceptual perspective, but, well, I continue to do so anyway... This question began plaguing me particularly after I started looking deeper into the nature of quantum indeterminacy, namely discovering that the many-worlds hypothesis had grown so unfavorable and that experimental data testing Bell's inequality show that local hidden variables cannot explain quantum indeterminacy. It's around then that I discovered the Bohm interpretation, which, as far as I can tell, posits a non-…

When do students normally start to learn about QFT? is it traditionally done in grad school?

alright so I have a t-shirt that says on the front "shrodinger's cat is dead", then on the back it says "schrodinger's cat is not dead". Mildly clever and good for a moments laugh but it gave me the idea for anouther t-shirt that would read on the front "schrodinger's cat is dead" then on the back "no, schrodinger's cat really is dead" then would follow a long and extensive proof saying that schrodinger's cat is dead. In order to make it so that schrodinger's cat is going to be dead I'm altering the thought experiment so that every second a random number generator spits out a one or a two, if its a one then the toxic gas isn't released and the cat stays …

http://www.red-ice.net/specialreports/2006/01jan/holographic.html I remember reading about this a while back. I think it's called Quantum Entanglement. However, this is much more in-depth about it. A very interesting read.

http://en.wikipedia.org/wiki/Bohr_Einstein_debate#The_principle_of_indeterminacy_applied_to_time_and_energy during the einstein bohr debates einstein proposed a very precise way of determining the amount of energy radiated in some very precise interval (detailed in the above link). originally stumped bohr later found a solution that showed that the error in the experiment corresponded exactly to the indeterminacy relation between time and energy. my question is if anyone here knows how to solve it out mathmatically as it seems like this would be a very cool derivation. (or if someone can find it layed out somewhere)

normally one thinks of oxygen as a gas, that can be condensed to form a liquid but at very high pressure molecular oxygen will crystalize to form a solid the crystals of oxygen can have COLOR in the range roughly 10-90 Gigapascal the crystal phase is called "epsilon" and it is RED color http://olivine.ethz.ch/~artem/Publications/JChemPhys-USPEX-2006.pdf'>http://olivine.ethz.ch/~artem/Publications/JChemPhys-USPEX-2006.pdf and a young Russian guy at Zurich ETH has succeeded in constructing a model that predicts crystal structures at various different levels of pressure here is his webpage http://olivine.ethz.ch/~artem/ the AIP Physics News Update pick…

In quantum mechanics it is assumed that any state can be expaned in terms of the eigenvectors of some operator. That is the eigenvectors form a basis for the Hilberts space. Does anyone know if this is automatic from the theory of Hilbert spaces and their operators or if it is a postulate of quantum mechanics?

In the free electron model (electrons in a box/conductor) why do we use periodic boundary conditions? What the idea/justification for it? I understand that, to have a unique solution to the SE, we need a boundary condition. We can either choose the wavefunction to be zero at the edges or periodic boundary conditions. The first will give rise to standing waves, the second traveling waves. I've heard things like: - Periodic boundary conditions is better, since we have travelling waves which makes the jump to the study of electron transport phenomena easier. That's pedagogically very cute, but doesn't give me any insight. - The idea is that the box is very big,…

Ok.. first off Im no physicist.. hell Im not even in school. I have a deep interest in Quantum Mechanics.. Ive been reading alot about it. I want to get a better grasp on both QED and QCD. What books would you guys/girls recommend?

Im a bit confused as to how the principle of quantum entanglement does not conflict with special relativity. Say for instance that a wavefunction consists of two particles which are entangled and far apart. If one particle is observed it results in the collapse of the entire wavefunction and an instantaneous effect on the entangled particle which can be noted by an observer. If one position of the affected particle would be considered a '0' and the other a '1' then it can be regarded as the transfer of information at faster than light speed. Does this not violate the principles of special relativity?

He said that if you think in terms of classical physics then you need the uncertainty principle.. but if you think with a soley quantum mindset you then the uncertainty principle isnt needed.. what did he mean by this? why would it not be needed?

Hi, I had just watched this video last night and I was wondering if anyone has any more information on the subject of electrons, and other particles for that matter, being in more than one place at the same time. Such as when you see an object, that object is actually in your brain as well. I can vaguely grasp this concept, but I was hoping someone could elaborate or at least lead me in the right direction.

This has something to do with all of physics and particularly equations used to solve problems with quantum physics. I need to solve this using Stone-Weierstrauss theorem for {sin(nx)} (n=1 to infinity) over the interval (0,pi/2) This involves the Fourier transform which would solve the series expansion starting with a0, am, & bm. This involves the use of a0=1/(2pi) INT(f(x))dx from (0,pi/2) and am=1/pi <cos(mx), f(x)> = 1/pi INT(f(x)*cos(mx))dx and bm=1/pi<sin(mx), f(x)> =1/pi INT(f(x)*sin(mx))dx. This is the dot product of the trig function and the function in L^2. The Stone-Weierstrauss uses three main conditions: 1) All x,y are in [a,b] th…

Please take a look at this new scientist (space) article... http://www.newscientistspace.com/article/mg19025533.900-spotting-the-quantum-tracks-of-gravity-waves.html More info on this arxiv article...the maths looks rather dense, so not sure if any physics experts can clarify the workings behind this theory ? (http://www.arxiv.org/quant-ph/0605135).

Hi every1, I've just been revising using my physics textbook(which is rubbish btw) and it mentions that the strong force actually gets stronger as the distance between 2 quarks increases(it uses the analogy of a rubber band).This is exactly opposite to both the gravitational force and electromagnetic force. If this is true, I'm curious about what forumulas govern the strength of this force or interaction also; is it proportional to r squared(r being distance between the 2 particles)? Also does anyone know why it gets stronger as the distance between 2 quarks increases?

I've just finished studying alpha decay, and found it quite simple...but beta decay is eluding me. How does a neutron change into a proton with the emission of an electron...it doesn't matter what the charge of the electron is beta minus or beta plus decay (obviously a positron with beta plus) but what is happening to the neutron to create a new element. I guess I'm missing something, but I thought photons only effected the position / speed et.c of electrons. Or does this decay have nothing to do with the absorption of photons ?

okay before i say anything else first let me apologize. my last posts were not well received because i do not know the language of science. so i am going to try VERY HARD here to keep my enquirey scientific in nature. i do not know science but have read about science ideas so please bare with me the idea i want to know about is SYMMETRY. as i understand SYMMETRY is a burning hot topic in science right now. physicsts think the entire universe can be described through symmetry. i think this too. physics is very important to symmetry. now i read about SPONTANEOUSLY BROKEN symmetry. if i understand it right, this is why there are no two snowflakes that are …

Can there be a single plane-polarized photon? One one hand they are bosons and I read that massless bosons are disallowed the zero spin state. (For masses, rules say <+L,-L> including integer states between.) Don't they have to carry angular momentum? How then can there be plane polarization, which we can see as superposition of opposite helicities, without two photons' worth of energy present?

I know I'm probably misusing the term "quantum event", so here's what I understand it to mean: A physical event that defies the laws of classical mechanics but is perfectly consistent with, and explainable by, the "laws" of quantum mechanics. I also understand that quantum events are more likely to occur the smaller the frame of reference is - that is, as one considers phenomena at lower and lower scales, one needs more and more to take quantum mechanics into consideration in order to make accurate (or close to accurate) predictions. So, then, here's my question: Was the Big Bang a quantum event? I've heard from sources I forget where that it was. If the B…

I ask this question solely for the purpose of testing my understanding of quantum mechanics. I want to ask, if the universe was to start all over again with the Big Bang, and assuming all conditions were exactly as they were 14 billion years ago, would we or would we not get exactly the same things we see on Earth today? Would I still be a web developer? Would I still have married the woman I'm married to? Would I still be here at my computer, typing these very words? From what I understand, the indeterminacy of the measurable properties of really small things means that the results predicted by classical mechanics are not met 100% of the time. So for example, one…

All, I've been doing some statistical analysis work on currency data and have reproduced interference patterns which have a good visual correlation to those seen in Young's double slit experiment. Does anyone know whether interference patterns such as these that underly a standard normal distribution have been produced elsewhere apart from the quantum level ? (Refernces would be appreciated TIA ).

Originally Posted by EvoN1020v Regardless, I found this interesting information on antimatter particles: The world's largest scientific research facility --- Switzerland's Conseil Europeen pour la Recherche Nucleaire (CERN) -- recently succeeded in producing the first particles of antimatter. Antimatter is identical to physical matter except that it is composed of particles whose electric charges are opposite to those found in normal matter. Antimatter is the most powerful energy source known to man. It releases energy with 100 percent efficiency (nuclear fission is 1.5 percent efficient). Antimatter creates no pollution or radiation, and a droplet could power N…

The list in my physics book reads 0.510 998 918 MeV/c^2 my Q is: how the hell do you measure something to 0.000 000 001 degree of accuracy? not to mention its in MeV/c^2 to start with!

Anyone with actual physics knowledge have something to say about this? http://www.esa.int/SPECIALS/GSP/SEM0L6OVGJE_0.html

Hi all I was wondering how you go about normalising the even bound state wavefunction for the finite square well? eg. so i have to find F and D. this what i got so far: i can't seem to find the answer to this 'normalising' problem anywhere! any ideas guys? Thanks Sarah