
1 PHY831 - Subject Exam Dec. 14th 2011, 10am - 1pm
... The mean field equation can be found in several ways, for example by doing the variation δF/δm = 0, or by finding the expectation < Si > using the mean field Hamiltonian. (iii) The first thing to note is that T anh(3βJm2 ) for ferromagnetic interactions (i.e. J > 0) is always positive, so there are ...
... The mean field equation can be found in several ways, for example by doing the variation δF/δm = 0, or by finding the expectation < Si > using the mean field Hamiltonian. (iii) The first thing to note is that T anh(3βJm2 ) for ferromagnetic interactions (i.e. J > 0) is always positive, so there are ...
LECTURE 10 Free Energy and Entropy Bose condensation is a
... For the case of Bose condensation, the Bose condensed state is described by a wavefunction or order parameter ψ = |ψ|eiφ . The broken symmetry is gauge symmetry by which we mean that everywhere in the system the phase is φ. This is what gives the state macroscopic phase coherence. Note that this val ...
... For the case of Bose condensation, the Bose condensed state is described by a wavefunction or order parameter ψ = |ψ|eiφ . The broken symmetry is gauge symmetry by which we mean that everywhere in the system the phase is φ. This is what gives the state macroscopic phase coherence. Note that this val ...
on the dynamics of radiation - International Mathematical Union
... new disturbances interact with the original exciting field and with its core ? For example, if we are dealing with a circuit of good conducting quality and finite cross section, situated in an alternating field of fairly rapid frequency, we know that the penetration of the arriving field into the co ...
... new disturbances interact with the original exciting field and with its core ? For example, if we are dealing with a circuit of good conducting quality and finite cross section, situated in an alternating field of fairly rapid frequency, we know that the penetration of the arriving field into the co ...
EXAM 1
... conducting cylindrical pipe of inner radius ri and outer radius ro. The pipe is electrically neutral, while the wire carries a uniform charge, with linear charge density λ. (a) ...
... conducting cylindrical pipe of inner radius ri and outer radius ro. The pipe is electrically neutral, while the wire carries a uniform charge, with linear charge density λ. (a) ...
On early and late phases of acceleration of the
... hope this presentation reflects in some sense the researcher every-day life, when he tries to grok concepts for his next works. The motivation to open this manuscript and start to read it could be nothing but the thirst to discover a point of view on the state of knowledge in cosmology in 2016. This ...
... hope this presentation reflects in some sense the researcher every-day life, when he tries to grok concepts for his next works. The motivation to open this manuscript and start to read it could be nothing but the thirst to discover a point of view on the state of knowledge in cosmology in 2016. This ...
Chapter 1 - Medical applications of physics
... Explain why the brakes are more effective if the lever is pulled at the end as shown. ...
... Explain why the brakes are more effective if the lever is pulled at the end as shown. ...
QOLECTURE4
... Δω is the detuning the frequency of the Rabi oscillations increases but their amplitude decreases as the light is tuned away from resonance for transitions in the visible-frequency range – observation of Rabi flopping requires powerful laser beams - pulsed, so that the electric field amplitude varie ...
... Δω is the detuning the frequency of the Rabi oscillations increases but their amplitude decreases as the light is tuned away from resonance for transitions in the visible-frequency range – observation of Rabi flopping requires powerful laser beams - pulsed, so that the electric field amplitude varie ...
Quantum-mechanical aspects of magnetic resonance imaging
... The proton is a fermion whose value of s is 1/2, therefore there will be two possible values for Sz , i.e. ±~/2. The eigenfunctions describing the nucleus can be written as | + 1/2i and | − 1/2i, and since in quantum mechanics every physical observable has an associated operator, we can write an eig ...
... The proton is a fermion whose value of s is 1/2, therefore there will be two possible values for Sz , i.e. ±~/2. The eigenfunctions describing the nucleus can be written as | + 1/2i and | − 1/2i, and since in quantum mechanics every physical observable has an associated operator, we can write an eig ...
On One-Fluid MHD Models with Electron Inertia
... ideal MHD has some limitations, such as in a specific regions where magnetic reconnection takes place, which is considered to have an important role in energy transfer. Other effects can also be important and the MHD model may breakdown for other reasons. Consequently, many researchers have consider ...
... ideal MHD has some limitations, such as in a specific regions where magnetic reconnection takes place, which is considered to have an important role in energy transfer. Other effects can also be important and the MHD model may breakdown for other reasons. Consequently, many researchers have consider ...
Chapter 29 - galileo.harvard.edu
... • What is a transformer? (Make a sketch) • How is the transformer equation derived? • What assumptions go into deriving the transformer equation? • What is meant by “step-up” and “stepdown” transformers, and how in general is this difference produced? • How and why are transformers used? ...
... • What is a transformer? (Make a sketch) • How is the transformer equation derived? • What assumptions go into deriving the transformer equation? • What is meant by “step-up” and “stepdown” transformers, and how in general is this difference produced? • How and why are transformers used? ...
Radiation reaction in ultrarelativistic laser
... related to bremsstrahlung since there is an energy loss mechanism. Lorentz considered the electron model in which the charge is distributed on a sphere to investigate this force. His model was applied only in the nonrelativistic regime, the case in which the electron has low velocity. One part of th ...
... related to bremsstrahlung since there is an energy loss mechanism. Lorentz considered the electron model in which the charge is distributed on a sphere to investigate this force. His model was applied only in the nonrelativistic regime, the case in which the electron has low velocity. One part of th ...
Paper 1
... Two charges, + Q and – Q, are placed a distance d from a negative charge – q. The charges, + Q and – Q, are located along lines that are perpendicular to each other as shown in the diagram below. +Q● d ...
... Two charges, + Q and – Q, are placed a distance d from a negative charge – q. The charges, + Q and – Q, are located along lines that are perpendicular to each other as shown in the diagram below. +Q● d ...
Solutions
... ferromagnetic [c]) which ones are used to make compass needles? Both diamagnets and paramagnets acquire magnetization only in the presence of a magnetic field. Compass needles operate by themselves, hence only ferromagnets can be used in a compass needle. 12. If the electric field in a plane electro ...
... ferromagnetic [c]) which ones are used to make compass needles? Both diamagnets and paramagnets acquire magnetization only in the presence of a magnetic field. Compass needles operate by themselves, hence only ferromagnets can be used in a compass needle. 12. If the electric field in a plane electro ...
Asymptotic Freedom: From Paradox to Paradigm
... two great theories of twentieth-century physics. Both are very successful. But these two theories are based on entirely different ideas, which are not easy to reconcile. In particular, special relativity puts space and time on the same footing, but quantum mechanics treats them very differently. Thi ...
... two great theories of twentieth-century physics. Both are very successful. But these two theories are based on entirely different ideas, which are not easy to reconcile. In particular, special relativity puts space and time on the same footing, but quantum mechanics treats them very differently. Thi ...
Assumptions and errors in the Lorentz force equation in
... direction, and this change of direction changes the direction of the induced field so that it remains at right angles to the direction of motion. This causes the charge to follow a circular path as shown rather than be accelerated away to the right of Figure 5. The consequence of this is that no ene ...
... direction, and this change of direction changes the direction of the induced field so that it remains at right angles to the direction of motion. This causes the charge to follow a circular path as shown rather than be accelerated away to the right of Figure 5. The consequence of this is that no ene ...
Asymptotic Freedom: From Paradox to Paradigm 1 A Pair of Paradoxes ∗
... two great theories of twentieth-century physics. Both are very successful. But these two theories are based on entirely different ideas, which are not easy to reconcile. In particular, special relativity puts space and time on the same footing, but quantum mechanics treats them very differently. Thi ...
... two great theories of twentieth-century physics. Both are very successful. But these two theories are based on entirely different ideas, which are not easy to reconcile. In particular, special relativity puts space and time on the same footing, but quantum mechanics treats them very differently. Thi ...
Magnetic resonance measurements of hyperfine structure using optical pumping Contents
... among other things, been used for hyperfine-structure investigations. The first motivation for doing theses investigations was to get a clearer understanding of fundamental physics, but such investigations have also resulted in atomic clocks and the definition of the second (the second is presently ...
... among other things, been used for hyperfine-structure investigations. The first motivation for doing theses investigations was to get a clearer understanding of fundamental physics, but such investigations have also resulted in atomic clocks and the definition of the second (the second is presently ...
Time in physics

Time in physics is defined by its measurement: time is what a clock reads. In classical, non-relativistic physics it is a scalar quantity and, like length, mass, and charge, is usually described as a fundamental quantity. Time can be combined mathematically with other physical quantities to derive other concepts such as motion, kinetic energy and time-dependent fields. Timekeeping is a complex of technological and scientific issues, and part of the foundation of recordkeeping.