Chapter 28 notes
... by emitting a photon with the same frequency and energy as the one originally absorbed. stimulated emission: an incident photon encounters an atom that’s already in an excited state with the same energy above the ground state as the photon’s energy; by a kind of resonance effect, the incoming photon ...
... by emitting a photon with the same frequency and energy as the one originally absorbed. stimulated emission: an incident photon encounters an atom that’s already in an excited state with the same energy above the ground state as the photon’s energy; by a kind of resonance effect, the incoming photon ...
Problem set 6
... Show that we can always define a new real function of time h(t) and a new hermitian operator H such that H(t) = h(t)H . Express h(t) and H in terms of c(t) and K and any other appropriate quantities. 2. Consider the functional equation for a complex-valued function of one real variable f (t + s) = f ...
... Show that we can always define a new real function of time h(t) and a new hermitian operator H such that H(t) = h(t)H . Express h(t) and H in terms of c(t) and K and any other appropriate quantities. 2. Consider the functional equation for a complex-valued function of one real variable f (t + s) = f ...
Nonlinearity in Classical and Quantum Physics
... go deeper into the structure and geometry of the phase space of Hamiltonian systems. This we do in order to define key concepts that describe the impact of non-linearity on the structure of the phase space, namely, integrability, its breaking due to perturbations, and the emergence of chaotic behavi ...
... go deeper into the structure and geometry of the phase space of Hamiltonian systems. This we do in order to define key concepts that describe the impact of non-linearity on the structure of the phase space, namely, integrability, its breaking due to perturbations, and the emergence of chaotic behavi ...
Heisenberg, Matrix Mechanics, and the Uncertainty Principle Genesis
... consider the simple example of a point particle that is free to move on a line. An observable in this case could be the position of the particle, represented by the matrix X. Since the particle could be anywhere on the line, the possible outcome of a measurement of its position could be any one of a ...
... consider the simple example of a point particle that is free to move on a line. An observable in this case could be the position of the particle, represented by the matrix X. Since the particle could be anywhere on the line, the possible outcome of a measurement of its position could be any one of a ...
PH5015 - Applications of Quantum Physics
... Quantum mechanics remains one of the most powerful but one of the least understood theories in physics. Typically students gain a good grounding in the theoretical and philosophical aspects of this topic but relatively little exposure to how quantum physics may be implemented in the laboratory and h ...
... Quantum mechanics remains one of the most powerful but one of the least understood theories in physics. Typically students gain a good grounding in the theoretical and philosophical aspects of this topic but relatively little exposure to how quantum physics may be implemented in the laboratory and h ...
Preprint
... is precision many body physics. Usually, the Hamiltonian for a cold atoms system is exactly known since the interactions in cold atomic gases are short range. Therefore, precision calculations of transition temperatures and other thermodynamic quantities are possible, and can be directly compared to ...
... is precision many body physics. Usually, the Hamiltonian for a cold atoms system is exactly known since the interactions in cold atomic gases are short range. Therefore, precision calculations of transition temperatures and other thermodynamic quantities are possible, and can be directly compared to ...
Document
... If the photon energy were large enough to eject the electron from the metal (here, W is the energy necessary to eject the electron), then energy of the photon absorbed (hυ) goes into ejecting the electron (W) plus any extra energy left over which would show up as kinetic energy (KE). ...
... If the photon energy were large enough to eject the electron from the metal (here, W is the energy necessary to eject the electron), then energy of the photon absorbed (hυ) goes into ejecting the electron (W) plus any extra energy left over which would show up as kinetic energy (KE). ...
Brane World - University of Southampton
... • Our theories of particles don’t fit with theories of gravity • String Theory is an attempt to construct a sensible theory of both • We are realizing it predicts wild possibilities • Extra dimensions and other Universes • Or are we a hologram in fewer dimensions? • Many exciting possibilities but v ...
... • Our theories of particles don’t fit with theories of gravity • String Theory is an attempt to construct a sensible theory of both • We are realizing it predicts wild possibilities • Extra dimensions and other Universes • Or are we a hologram in fewer dimensions? • Many exciting possibilities but v ...
Particle in a box
In quantum mechanics, the particle in a box model (also known as the infinite potential well or the infinite square well) describes a particle free to move in a small space surrounded by impenetrable barriers. The model is mainly used as a hypothetical example to illustrate the differences between classical and quantum systems. In classical systems, for example a ball trapped inside a large box, the particle can move at any speed within the box and it is no more likely to be found at one position than another. However, when the well becomes very narrow (on the scale of a few nanometers), quantum effects become important. The particle may only occupy certain positive energy levels. Likewise, it can never have zero energy, meaning that the particle can never ""sit still"". Additionally, it is more likely to be found at certain positions than at others, depending on its energy level. The particle may never be detected at certain positions, known as spatial nodes.The particle in a box model provides one of the very few problems in quantum mechanics which can be solved analytically, without approximations. This means that the observable properties of the particle (such as its energy and position) are related to the mass of the particle and the width of the well by simple mathematical expressions. Due to its simplicity, the model allows insight into quantum effects without the need for complicated mathematics. It is one of the first quantum mechanics problems taught in undergraduate physics courses, and it is commonly used as an approximation for more complicated quantum systems.