Quantum Theory

I came across this in one of the 'letters' written to the New Scientist in March 8th's issue. It's a response to an article I don't recall in much detail, to be honest, but was apparently someone arguing for the existence of infinite universes. I thought this was a pretty ingenious little refutation. But is it just a word game or do the physics actually work here?

what are some similarities and differences between measuring an object in the quantum world and measuring an object in the macroscopic world? Any input is appreciated

I'm sure many people on this forum must have heard about the QMC@home project and I want to know what you think about it. Is it worth participating or is it just a waste of time and resources? Greetings!

Has there been any work modeling cosmic inflation using quantum decoherence? I have been all over the net for this stuff if it exists. Thanks for the time:D

I need a little help understanding how quanta and elementary particles tie in to quantum mechanics. I understand both of them, but it's the concept of quantum mechanics that gets me, it seems really random. Can someone help explain the concept to me?

Currently standard IUPAC Periodic Table is based on metallic/nonmetallic properties of the elements. But, I believe, it is going to change rather soon. The Periodic Table can be formulated to follow the Quantum Numbers n, l, ml and ms, as recently was demonstrated (ADOMAH PT). The true Periodic Table have to follow natural grouping of the elements in accordance with the n+l rule, which is the basis for the periodicity. It was reported recently that element 114 (Uuq), that was expected to be similar to lead (Pb), behaves more like a noble gas ! The more we find out about heavy elements the more surprises we'll get and the good old IUPAC PT will not hold.

In old periodic tables La was listed in 5d subshell, that corresponds to n=5 and l=2 quantum numbers. Modern IUPAC table lists it in 4f subshell, that corresponds to n=4, l=3. It is known that La has no 4f electron, but it did not stop IUPAC from listing it in 4f. What is correct eigenvalue of the last distinct electron to be used for the solving Schrodinger equation for example? Should n=4 and l=3 be used? I

What is the shape of physical waves? I would assume they are usually sin waves, but is it possible to have a shaped wave like square or triangle occur naturally? How would the shape of a wave be determined?

In the Schrodingers cat argument a phial of poison is triggered by a random atomic event. The argument in this case was would the cat be in a superposition of being alive and dead before we open the box to find out the fate of the cat. Here is a new slant that may have been said already. Let's face it there are plenty of brainier people in this field than me! We create a pair of entangled photons. They are directed along equal paths to the poison phial. In this case the trigger on the poison device is as follows: should the detector find a photon is polarised in the vertical plane the device is completely de-activated. Should it, however, detect a photon is polar…

Hi everybody Well I'm ashish from INDIA (Chhattisgarh,RAIPUR). I'm final year Engineering student from Information Technology branch. When I was in 12th standard, at that time Physics was my favorite subject and till now. But when I studied physics in the foundation course of first year really I used to get confused by quantum meshanics, there used to be so much of problems regarding that what should I think Light as a wave or a particle. And I have come up to a thought that there is nothing like a wave and its just a way of represention of various physical phenomenon So from that time I have a very great enthusiasm about Q…

I get that strings exist as an expression of one dimensional existence, but how can something exist in one dimension? From my understanding this is more of a mathematical expression than an actual object existing in one dimension, but if this is a viable theory, then that math actually does mean something. So how could something exist as a one dimensional object? Could it have only height, and no width or length for example? This seems impossible. The only dimension I could see existing on it's own, would be time (even though without matter the concept would be moot). I'm sure this is an incorrect assertion, but why? What other dimension could stand alone?

I'm asked to find the ZPE of 1m³ of air, assuming it is all nitrogen. Here's what I did: 1) use PV=nkT to find the number of particles in 1m³ P = 1.01 * 10^5 k = Boltzman's consant T = 298 K and got n = 2.5 * 10^25 per m³. 2) I am given that the "spring constant" (this is all approximate) in nitrogen is s = 2240 N/m. Atomic mass is 14, reduced mass, μ, of N-N system is 7. Converting 7 from AMU to kg and using ω=√(s/m) I get ω=4.39*10^14. 3) I'm then told E=ħω/2. I stick in ħ and my value of ω, multiply by the number of molecules in a m³ of air and get the total ZPE in 1m³ of air is ~6*10^5 J. If I made a mistake please let me know where. If I did n…

About set theory with urelements and elementary particles Platonists seek a reality in mathematics, associated with the truth of axioms. Logicists and formalists are concerned about consistency and independence of axioms but not about their truth. I suggest, as a Platonist, that the axioms definitely true are those applied to previously unsolved mathematical problems or to physics or social sciences or ethics. For the case of the axiom of choice, I state that the negation of the axiom of choice is true because I apply it to quantum mechanics and cosmology which are part of physics. It is because of the lack of interdisciplinary research that the status…

Is it possible to use predictions from chaos theory to compensate for quantum uncertainty? If something small can have exponential repercussions, could those large-scale observations be extrapolated backwards to determine the initial state, at the same time as directly observing the initial state of another property?

I have questions. Questions that I have been trying to figure out for myself, but now I have realized that I need professional help. An electron has a charge, and is a source of an electric field. A moving charge has the property that it is a source of a magnetic field. What should the charge be moving in relation to, in order to consider it a "moving" charge? Are not all charges moving in some sense, and thus be affected by all other charges however slightly? I set up a measuring device, at some point in space, that can measure electric force as well as the magnetic force, so that I can measure moving charges (as well as non-moving). If I shoot one charge in s…

I have to say, although I like the ideas of strings being the interworkings of everything, it seems like its taken on a life of its own, with 11 dimensions, parallel universes, membranes, and whatnot. It seems too -weird- for it to be plausible. I guess we'll just have to wait till CERN is built... but, I do have a question too. Isnt it possible to have Gravitons, and such, without string theory? Because I cant help but think that there's quite possibly another explanation that we havent explored yet.

A colleague of mine started to teach an introductory course in wave mechanics and asked me what the units of the wave function in quantum mechanics is. Thus, if we interpret the absolute square of the wave function as a probability density, does it in fact mean that the units of the wave function is per square root of length in the one-dimensional case? Johan

We experience electrons as highly local points when we force high energy interactions. This I've heard characterized at maybe 10^-21 meters, and such interactions have very short time spans. On the other hand we have the uncertainty (at longer time frames?) of position and momentum of the quantum state called in this case zitterbewegung. This shows the intimacy of relation between the "particle state" and the zero-point quantum field. It is not a coincidence that the product of momentum characteristic of an electron orbit, multiplied by characteristic atom size, is about equal to Planck's constant. My primary question here is, does the uncertainty produce an average …

About experimenting about elementary particles about space and time That ZFU (set theory with urelements, non sets) is applied to space and time explains the correlations between particles (in "An interpretation about space and time in quantum mechanics") in Logic Colloquium 2007. ZFU applied to elementary particles is most likely to explain the Big Bang, see http://www.scienceforums.net/forum/showthread.php?t=30616 As the usual distance is not defined, we consider the distance between particles number of urelements in between + 1 Mr Andreas Blass remarked that if the urelements are ordered by the experiment set up, measurement may vary with the ord…

I would just like to submit my understanding of decoherence to scrutiny. Basically does decoherence exist as a possible answer to the measurement problem of quantum mechanics from postulating that entanglement gives rise to environments or more of the same?

About a distance for elementary particles In "An interpretation about space and time in quantum mechanics" in Logic Colloquium 2007, we have seen that the usual distance is not defined for space and time because we apply the theory ZFU (set theory with urelements, non sets). We explained some correlations between particles. I would have doubts about the assumptions if I did not apply them for space successfully to explain the Big Crunch and the Big Bang in http://adibjebara.blogspot.com/ As time is but another dimension, I apply ZFU to time as well. Now, let U1xU2 be space time with U1 space and U2 time. Many things are discontinuous in quantum me…

What is responsible for the color of light? 1) Frequency 2) Wavelength or any thing else

The HUP says that the more precision with which you measure position, the less precisely can you know momentum, and visa-versa. What if you're not measuring either? What can be said of a particle's position and momentum in that case? Are they both equally (and highly) uncertain? Well, of course they are - if you don't measure either, how can you know either? - but aren't quantum physicists in the habit of taking epistemological statements and treating them as interchangeable with ontological ones? I mean, wouldn't a hardnosed positivist say that if you don't know either the particle's position or its momentum, then it actually has neither to any precision? And if that…

How can a wave have energy please explain it?

My question is simple, but I can't find an answer with google or wiki:( How does Plank found that value ? [math]h=6.6*10^{-34} J s[/math] How did he derived it ? Thanks