# Tag Info

## New answers tagged wave-particle-duality

0

You want a high school level answer. I will try. There are fundamental definitions established at the creation of the universe. Physicists have deduced many of these fundamental quantities, which define relationships between things like matter, energy and even time. One fundamental definition is the invariant speed of light, and the fact that by ...

4

The question doesn't have an answer because electrons aren't waves and they aren't particles. This is a common source of confusion, and has led to the endless debates about wave particle duality. Quantum systems are described by a wavefunction that can behave as a wave in some circumstances and behave like a particle in others.However it is vital to ...

0

I think you may have a slight misconception regarding the actual meaning of an electromagnetic wave. Electro-magnetic waves are thought to be functions of probability of finding a photon at a certain point in space. Read some information on the photoelectric effect this may provide some more clarification.

0

John is right. I just want to try to give a more intuitive explanation. Suppose you plot the sine and cosine of a wave that has a wavelength of exactly 1. Then of course the peaks and zero-crossings would be exactly 1 unit apart. Now suppose you put an envelope on that plot, such as multiplying it by $x$. Here's that plot: Notice the zero-crossings of ...

1

Yeah, they can have a representation as a wave. What you have to realize is that we have absolutely no intuition about the world at particle scales. Here, in the macroscopic world, we easily distinguish thing as particles or waves. For example, sound and the motion of a string are clearly waves to us, while a basketball and a car are clearly particles. Non ...

0

I think a much more natural way to come to $\hbar$ is the one used by Dirac in his principles of quantum mechanics. In it you start by stating that you want a Poisson Bracket which has the same algebraic structure as that of classical mechanics. Then, since quantum operators don't commute (unlike what happens in classical physics) you quickly find out that ...

2

Q1: For photons of energies much less gamma rays, the quantum mechanical photon-photon interaction is negligible. This is consistent with the classical electrodynamic description where the principle of superposition holds (electromagnetic waves pass through each other unchanged, as well as through electric/magnetic fields). Q2: in reality, charge is defined ...

0

An electromagnetic wave is a transverse wave, and we can make an electron and a positron out of it in pair production. Then we can diffract the electron, and even refract it. We can also polarize electron beams. Then we can annihilate the electron with the positron, and get two or three electromagnetic waves, which are transverse waves. So the hard ...

4

we all know waves are of two types transverse and longitudinal, and we do have studied about de broglie wave as well,so which ond of them is it?. or we have other means to classify them.. For a wave to be either transverse of longitudinal it must be a vector field quantity (e.g., the electric field). This is because "transverse" means that the ...

0

According to Quantum mechanics a particle exists in a state $|{\Psi}\rangle$ which belongs to a hilbert space of states. When you make a measurement, you act on the state with an operator, say $A$. And by doing this you project the state $|{\Psi}\rangle$ onto the subspace spanned by the eigenvectors of $A$, so now your state is one of the eigenvectors of $A$ ...

0

No a measurement doesn't have to change the state of the system, but it has to at least has the possibility to change the apparatus; otherwise you wouldn't call it measurement. The change to the environment(the apparatus , the scientist and everything that interact with it) is what cause you to lose interference pattern. This is usually called decoherence ...

0

Does the measurement of the particle change it's physical state? A measurement, as an evaluation of given observational data, does not have any direct physical effect other than being accompanied by a change of state by whoever carries out the evaluation; the state changing from not yet knowing the result value (or indeed whether one could be obtained ...

-2

It is a real wave associated with electron. And we adopt its mathematical description using wave function in configuration space

0

The double slit experiment basically shows these results, which is quite extraordinary in my view. If an electron is fired from a gun one at a time towards a double slit, we will see interference pattern (vertical bars), which kind of shows what water wave will show if it hits a shore for instance. Because of interference, some systematic areas on the board ...

2

What they actually measured was not particle behavior. It was just a quantized energy transfer to the probing electrons. That corresponds to the absorption of individual photons, but it doesn't mean the Surface Plasmon Polariton (SPP) field was acting as a particle. It just interacted locally with the electron, as it must. Typically particle-like behavior ...

1

Quantum mechanical entities are described by solutions of the Schrodinger equation, the wave function, with specific boundary conditions. A measurement changes the boundary conditions and thus the subsequent wavefunction describing the particle measured will be a different one. A measurement picks an instant from the probability distribution describing the ...

0

There is indeed a way wherein "one photon" can be thought of as a Maxwellian wave. We are dealing here with the quantized electromagnetic field. If the EM field is in a one photon state then one can compute two vector fields from the EM field's state that: Fulfill Maxwell's equations for freespace propagation and Uniquely define the one photon state. ...

2

The maxwellian wave is an emergent phenomenon from a great multitude of photons with the frequency of the maxwellian wave. This is explained in this blog entry by Lubos Motl. I will give you my experimentalist's interpretation of this: A photon as a quantum mechanical entity has a wavefunction. This wavefunction is a solution of a form of Maxwell's ...

0

It turns out that light can be thought of as a wave and a particle under different conditions. For example, as Cort Ammon described, the Double Slit experiment showed that light had properties of diffraction. On the other hand, the photoelectric effect considers light as packets of light called photons with certain energy $hf$. Another such experiment is the ...

0

Another way of thinking of this is to imagine that space-and-time is an emergent phenomenon, NOT a pre-existent framework that holds photons, be they waves or particles. If space/time emerges for example at the quantum level of individual photons, effectively there may be no immediate space and time there for a wave to propagate through. But at larger ...

0

Look into Wave-particle duality. It is a major part of Quantum Mechanics which answers your question. A quick summary: light is not just a wave, not just a particle. In some situations it behaves like a wave; in others it behaves like a particle. In some situations, neither wave nor particle sufficiently describe reality. A solid example of this is the ...

1

The interference pattern appears when the two slits are at a distance of the order of the wavelength of the incoming waves. This is classical wave dynamics, nothing quantum to it. The quantum part is that particles are actually waves, and have an associated de Broglie wavelength, which depends inversely on their mass. Presumably, making your objects heavier ...

2

In it's simplest form, de Broglie's hypothesis is meant to be applied to fundamental, indivisible particles, like an electron (an electron is fundamental and indivisible to within our current experimental precision at least). In that case it doesn't make semse to talk about half an electron, or to divide the mass of the electron among its parts. There is a ...

0

in Quantum Mechanics interferences is when the wave function of one (or more) particle can take several paths and then later cross. The complex amplitude adds up and you have an interference. Negative interference if the probability gets smaller at one point or positive if the probability gets higher. The definition is mostly qualitative here. Entanglement ...

0

They are different things. Interference Is an intrinsically quantum phenomenon that arises form the fact that transition probabilities between different pure states can be non-zero, as opposed to classical mechanics, where such transition probability is always zero. Entanglement Is a property of a state of a composite system, expressed as the tensor ...

1

The stage in science where this conflict arises marks the dawn of a new mechanism to understand and thereby attend to some questions that have remained unanswered since the last thousands of years before humanity. The hint lies not in the particle or the wave. Infact we need to look deeper, into things that are still more subtler! Here science declares these ...

Top 50 recent answers are included