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What do we actualy mean a matter or particle having both wave and matter properties, and do the electrons occilate that means it has both up and down with the translational motion around the atom!
To plump it out - nobody knows what it 'actually' means.What do we actualy mean a matter or particle having both wave and matter properties, and do the electrons occilate that means it has both up and down with the translational motion around the atom!
Electrons are particles. So are photons. The wavelike properties that these particles exhibit are a result of the particle's wavefunction -- the fact that these particles obey probabilistic mechanics manifests itself in the wave-like properties that we observe in macroscopic experiments. There's really nothing funny going on.What do we actualy mean a matter or particle having both wave and matter properties, and do the electrons occilate that means it has both up and down with the translational motion around the atom!
Things that behave as waves and particles depending on if they are being observed. Things that seem to exist in some ethereal manner whereby they pop in and out of our existance that we cannot identify both speed and position of . Transfer of information faster than light speed seemingly over any distances . Nothing funny going on has to be the greatest understatement of all time .Electrons are particles. So are photons. The wavelike properties that these particles exhibit are a result of the particle's wavefunction -- the fact that these particles obey probabilistic mechanics manifests itself in the wave-like properties that we observe in macroscopic experiments. There's really nothing funny going on.
There aren't any instances of faster than light transfer of information. And there is nothing that prevents us from measuring the speed and position of an object either. A lot of the confusion arises from attempts to describe quantum behavior in terms of classical phenomenon. The actual quantum theory treats the behavior of objects in a consistent manner.Things that behave as waves and particles depending on if they are being observed. Things that seem to exist in some ethereal manner whereby they pop in and out of our existance that we cannot identify both speed and position of . Transfer of information faster than light speed seemingly over any distances . Nothing funny going on has to be the greatest understatement of all time .
You may want to start by reading the FAQ thread in the General Physics forum.Hallow no one is giving me answers seriously, may anyone help me have a picture of the wave particle duality and probably giving in detail the uncertainity principle and the wave function as been stated in some replies
The uncertainty principle is primarily a relationship on the statistical results of a measurement. We are perfectly able to measure the position and momentum of a particle simultaneously. What the uncertainty principle states though is that if we were to take a large number of identical measurements, then the variance (or spread) of the position and momentum are related. If we are able to have a low variance in the position measurements, then this correlates to a limit on the variance in the momentum measurements. This does not mean to say that it is a completely causal phenomenon. For example, people often ascribe the electron cloud as being a consequence of uncertainty. However, that could not be any further from the truth. The electron cloud, for example, is precisely predicted by the wavefunction and assumes a deterministic position and energy of the electrons. The uncertainty priniple is only involved in terms of measurements.Really , could you shed some light on the results of the aspect experiments then and explain Bells ineqaulity perhaps i have misunderstood them . Also from your reply it also appears I do not understand the uncertainty principle could you also expand on that .
Particles do not follow all possible paths nor are they allowed to violate special relativity (any formulation that allows such violation is one that does not include special relativity, most of quantum mechanics uses non-relativistic theory). The path formulations are a mathematical tool and are not considered to have any true physical correlation. Particles can appear and disappear by virtue of special relativity. This does not have anything to do with quantum mechanics. If we have a system with a certain amount of energy, then that energy can convert into a particle by virtue of the Relativity's equivalence principle. If we couple special relativity with quantum mechanics, then we simply provide a mechanism for the creation and annihilation of particles via the equivalence principle. The only really quantum behavior here lies with virtual particles. Virtual particles are particles that are created from and annihilated into energy on very short time scales to the effect that they are not considered to be real particles. This occurs because observation of a system over a very small time interval requires a large variance in the observed energy states by virtue of the uncertainty principle. Since the energy can vary, then the system could momentarily have a large enough energy to create a particle, but since this energy spike is fleeting, so is the particle's lifetime. But at the same time, virtual particles are another mathematical tool. They are not considered to be truly physical and it is important to note that we are not saying that a bunch of energy is created from nothing when we consider these short-term time spans, but that variance in the observed energy is large.Godwin Kessy I will do my best. In certain circumstances particles can exhibit the behaviour of both waves and particles and it rather depends on what one is seeking to measure that determines which. |The obvious example being light which moves as a wave but is comprised of photons.
The uncertainty principle states that we cannot accurately measure certain pairs of physical properties of particles for example position and velocity or energy and time. The more accurately we measure one of the pair the less accurately we can measure the other.
These principles appear to me to be predicated on the rather ethereal life of particles which appear to reside in a universe of total uncertainty whereby one can only gauge the likelihood of their appearance in our physical universe. Furthermore they appear to be able to travel on all paths between points which given that they travel at C and therefore have infinite time available seems quite possible. It’s only when we look for them that this behavior is modified and they appear in our world.
The actual mechanism of observation is not considered. However I have seen explainations that follow along such lines. For example, in Feynman's path integral text he explains the uncertainty in terms of purely mechanical methods. I can't remember it well enough now to say more on the matter but I will say that the uncertainty principle can be borne out completely by the mathematics of quantum mechanics.As others have said the uncertainty principle is just a statistical expression of where a particle may be and how fast it may be moving. When determining the position or momentum of the particle in question we must "look" for it through the agency of light which disturbs the particle in such a way that the complimentary measurement will be a probability.
The wave particle duality comes from the famous double slit experiment in which electron particles as well as photons were shot at a wall with two slits and a detector on the other side. When dealing with particles one would expect to see two lines of particles on the detector, however an interference pattern is present which is characteristic of waves. This happens even when there is only one particle travelling through the slits. If any of this is incorrect please set me straight. Hope that helps the OP.
Joe
I gave you a serious answer.Hallow no one is giving me answers seriously, may anyone help me have a picture of the wave particle duality and probably giving in detail the uncertainity principle and the wave function as been stated in some replies
Most of what you just wrote down there doesn't make any sense. There's lots funny going on with your statements. My point, if you read my post ever so carefully, is that wave particle duality is not some spooky statement regarding our inability to assign an identity to subatomic particles.Things that behave as waves and particles depending on if they are being observed. Things that seem to exist in some ethereal manner whereby they pop in and out of our existance that we cannot identify both speed and position of . Transfer of information faster than light speed seemingly over any distances . Nothing funny going on has to be the greatest understatement of all time .
In quantum mechanics, the Heisenberg uncertainty principle states that certain pairs of physical properties, like position and momentum, cannot both be known to arbitrary precision. That is, the more precisely one property is known, the less precisely the other can be known. Could you expand on the manner in which you have managed to ovwercome this please.The uncertainty principle is primarily a relationship on the statistical results of a measurement. We are perfectly able to measure the position and momentum of a particle simultaneously.
In Bell's inequality, there is no means for us to set the entangled state to our liking. There is no means for us to transfer information.
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Particles do not follow all possible paths nor are they allowed to violate special relativity (any formulation that allows such violation is one that does not include special relativity, most of quantum mechanics uses non-relativistic theory). The path formulations are a mathematical tool and are not considered to have any true physical correlation. Particles can appear and disappear by virtue of special relativity. This does not have anything to do with quantum mechanics. If we have a system with a certain amount of energy, then that energy can convert into a particle by virtue of the Relativity's equivalence principle. If we couple special relativity with quantum mechanics, then we simply provide a mechanism for the creation and annihilation of particles via the equivalence principle. The only really quantum behavior here lies with virtual particles. Virtual particles are particles that are created from and annihilated into energy on very short time scales to the effect that they are not considered to be real particles. This occurs because observation of a system over a very small time interval requires a large variance in the observed energy states by virtue of the uncertainty principle. Since the energy can vary, then the system could momentarily have a large enough energy to create a particle, but since this energy spike is fleeting, so is the particle's lifetime. But at the same time, virtual particles are another mathematical tool. They are not considered to be truly physical and it is important to note that we are not saying that a bunch of energy is created from nothing when we consider these short-term time spans, but that variance in the observed energy is large.
FTL transmittion of information has been DEMONSTRATED?In quantum mechanics, the Heisenberg uncertainty principle states that certain pairs of physical properties, like position and momentum, cannot both be known to arbitrary precision. That is, the more precisely one property is known, the less precisely the other can be known. Could you expand on the manner in which you have managed to ovwercome this please.
I did not suggest that we could transmit information faster than light by means of entanglement merely that it has been demonstrated to have occured in the aspect experiments and others that followed
in QED, light (or any other particle like an electron or a proton) passes over every possible path allowed by apertures or lenses. The observer (at a particular location) simply detects the mathematical result of all wave functions added up.
For the last two. Information has not been transferred faster than light in any experiments. The reason, as I explained previously, is that we cannot predetermine what the measurement will be. Thus, there is no mechanism by which we can send a desired signal. It is essentially stating that Professor Busybee always wears one red and one green sock. If you know the left sock is red, then you automatically know that the other sock is green. But you cannot force the Professor to wear a red sock on his left foot so there is no information transferred here. If we could force the left sock to turn up red or green at our behest, then we could come up with a way to somehow ship a succession of the poor Professor's right foot to some recipient far away and send a coded message by manipulating the color of socks that he would see. Using Professor Busybee in this manner is incorrect (and inhumane, I'm sure he's rather attached to his appendages) because the Professor makes a conscious choice in his sock selection, he predetermined the colors in what can be described as a hidden variable. The Bell inequality is what challenges such hidden variables but I only use him as a visual aid.In quantum mechanics, the Heisenberg uncertainty principle states that certain pairs of physical properties, like position and momentum, cannot both be known to arbitrary precision. That is, the more precisely one property is known, the less precisely the other can be known. Could you expand on the manner in which you have managed to ovwercome this please.
I did not suggest that we could transmit information faster than light by means of entanglement merely that it has been demonstrated to have occured in the aspect experiments and others that followed
in QED, light (or any other particle like an electron or a proton) passes over every possible path allowed by apertures or lenses. The observer (at a particular location) simply detects the mathematical result of all wave functions added up.
Hallow! I gec am almost out of phase may you people help me out slowly, i am seriously in need to understand out! We are using so unfamiliar terms with no descriptions! Ie relativity,
When we do experiments with single electrons or photons, they always are detected as particles. i.e. they are localized in space and time. For example, if the particles are detected on a fluorescent screen they appear as dots, one dot at a time for each particle. There is no evidence of any wave behavior in a single dot.What do we actualy mean a matter or particle having both wave and matter properties, and do the electrons occilate that means it has both up and down with the translational motion around the atom!
What about experiments suggesting single particles can interfere with themselves and yield interference patterns?(we also have the experiments that say a particle, even a molecule, can be in two places at the same time, which would suggest how it could interfere with itself by passing through two slits at once.)When we do experiments with single electrons or photons, they always are detected as particles. i.e. they are localized in space and time. For example, if the particles are detected on a fluorescent screen they appear as dots, one dot at a time for each particle. There is no evidence of any wave behavior in a single dot.
If we take this to be right, even an individual particle cannot have both properties at the same time even if it is not measured, it exists without both these things being definitive. The wiki article has even more strange quantum behavior, such as that the failure to measure(e.g. it fails to hit the detector, if I'm not mistaken.), failure to interact with something, can also disturb the particle.The amount of left-over uncertainty can never be reduced below the limit set by the uncertainty principle, no matter what the measurement process...
Today, logical positivism has become unfashionable in many cases, so the explanation of the uncertainty principle in terms of observer effect can be misleading. For one, this explanation makes it seem to the non positivist that the disturbances are not a property of the particle, but a property of the measurement process— the particle secretly does have a definite position and a definite momentum, but the experimental devices we have are not good enough to find out what these are. This interpretation is not compatible with standard quantum mechanics. In quantum mechanics, states which have both definite position and definite momentum at the same time just don't exist.
This was a surprising prediction of quantum mechanics, and not yet accepted. Many people would have considered it a flaw that there are no states of definite position and momentum. Heisenberg was trying to show this was not a bug, but a feature—a deep, surprising aspect of the universe.
Since most hidden variable theories assume nonlocality and keep CFD, since one of the two has to go(according to the experimental data), as these [hidden variable theories] are usually dismissed, I assume what was tossed out of mainstream quantum physics was CFD and locality was kept in(If I recall correctly, I've heard locality was kept for compatibility with relativity.) . Such that all the unmeasured properties are believed to not be definitive for something that has not been measured(aka, if we exaggerate or use metaphor: "the moon is not there when you don't look."). It seems more sensible to throw out locality and keep CFD, and sort out any conflicts that may arise with regards to relativity.Counterfactual definiteness is a basic assumption, which, together with locality, leads to Bell inequalities. In their derivation it is explicitly assumed that every possible measurement, even if not performed, would have yielded a single definite result. Bell's Theorem actually proves that every quantum theory must violate either locality or CFD.
There is no contradiction ... the photon is always *detected* at a single point (i.e. pixel). You do not detect interference patterns for a single experiment with a single photon ... interference patterns are built up out of dots (i.e. single photon detection events), over a series of repeated experiments, each with a single photon.What about experiments suggesting single particles can interfere with themselves and yield interference patterns?(we also have the experiments that say a particle, even a molecule, can be in two places at the same time, which would suggest how it could interfere with itself by passing through two slits at once.)
That is correct for undetected particles (according to standard QM), however it is *not* correct for particles that have interacted with a detector. When you measure a single particle, you measure it's properties with a precision that is determined *only* by the measurement precision, which can be taken to be infinitely good for the sake of this argument. There is *no* fundamental limit on the measurement precision for a single particle .. this is because the phenomenon of quantum decoherence that occurs upon detection causes the system (particle and detector) to be resolved into a single measurement state (i.e. eigenstate of the property being measured).As for the description of uncertainty, according to wiki
If we take this to be right, even an individual particle cannot have both properties at the same time even if it is not measured, it exists without both these things being definitive.
According to one of the last https://www.physicsforums.com/showthread.php?t=57528" the data suggests that each individual particle must be interfering with itself to give the observed results. It seems you agree, that it can interfere with itself, so it indirectly shows that even individual single photons and particles can showcase wavelike behavior.There is no contradiction ... the photon is always *detected* at a single point (i.e. pixel). You do not detect interference patterns for a single experiment with a single photon ... interference patterns are built up out of dots (i.e. single photon detection events), over a series of repeated experiments, each with a single photon.
So yes, as long as the experiment does not detect which-path information, then each single photon travels along both paths, interferes with itself, and is detected at some point on the detector screen. The probability of it being detected at any given point is determined by the quantum interference.
Ifhttp://en.wikipedia.org/wiki/Renninger_negative-result_experiment" [Broken] with a detector can disturb a particle and thus bring uncertainty, how can you be sure that your particular interaction with a particular detector is not affected by the lack of interactions with other parts disturbing the particle?That is correct for undetected particles (according to standard QM), however it is *not* correct for particles that have interacted with a detector. When you measure a single particle, you measure it's properties with a precision that is determined *only* by the measurement precision, which can be taken to be infinitely good for the sake of this argument. There is *no* fundamental limit on the measurement precision for a single particle .. this is because the phenomenon of quantum decoherence that occurs upon detection causes the system (particle and detector) to be resolved into a single measurement state (i.e. eigenstate of the property being measured).
If the particle happened to exist in a single eigenstate of the measured property before measurement, then only that particular eigenstate will be measured, no matter how many times the experiment is repeated for identical conditions. However, if the particle existed in a superposition of eigenstates (as is true in the case we are considering for position and momentum measurements), then a series of measurements will observe a range of results, where the distribution is determined by the probability envelope of the superposition, which is in turn limited according to the HUP.