Gauge Definition and 641 Threads

Does anyone know a deep reason why we always put the gauge fields in the adjoint representation of the group? I am not sure if there is a deep reason or it's just that it "happens" to work for SU(2) and SU(3). Just wondering.

First, I am not the greatest at LaTex so if I screw this post up I will go back and try to clarify. I will skip some steps, but get the general gist of everything. Ok, I am following the derivation of the resistive strain gauge equations starting from the basic form of resistance of a wire...

Could somebody please give me a definition for the term gauge symmetry in contrast to any other symmetry? Is the decisive difference that a gauge symmetry is local i.e. a function of the coordinates in contrast to being constant? I would also appreciate it if it could be pointed out how the...

I've gotten out most of this question, it's really just the last part that's getting to me at this stage. I'd never seen the http://mathworld.wolfram.com/DeltaFunction.html" before so it might be because of that. I've an idea how to do it but I just end up in a mess of partial derivatives. I'd...

[b]1. Homework Statement [/b An automobile tire having a temperature of .64 degrees C is filled to a gauge pressure of 27 lb ft/in2. What would be the gauge pressure in the tire when its temperature rises to 39 degrees C? Homework Equations Assume the volume remains constant, the air...

For my diploma thesis I must provide a calculation that reproduces the results given on page 46 of the paper hep-ph/0309342 . For those who do not want to look it up, I briefly explain what it is about: It concerns the two-body scattering processes (1) N + V => L + H, (2) N + L => V + H, (3) N...

Homework Statement A tire contains air at a gauge pressure of 4.86x10^4 Pa at a temperature of 25*C. After nightfall the temperature drops to -10*C. Find the new gauge pressure in the tire. Pa Homework Equations Pa_i/T_i = Pa_f/T_f T = T_c + 273 The Attempt at a Solution...

A village maintains a large tank with an open top, containing water for emergencies. The water can drain from the tank through a hose of diameter 6.60cm. the hose ends with a nozzle of diameter 2.20 cm. A rubber stopper is inserted into the nozzle. the water level in the tank is kept 7.50 m...

"An automobile tire is filled to a gauge pressure of 200 kPa when its temperature is 20C. (Gauge pressure is the difference between the actual pressure and atmostpheric pressure.) After the car has been driven at high speeds, the tires temperature increases to 50C. Assuming that the volume of...

Everytime a photon leaves an atom, the energy of that photon is matched by the increase in binding energy of that atom - right? If so would the change of energy in the form of radiation be equivalent to the change of binding energy? Is the aggregate binding energy of particles in the...

Need help. Is there a simple formula to calculate the gauge of wire to use vs. length for a know amp rating of a device. I have a device I need to install a couple of hundred feet from the house and know the amps it pulls but do not know the formula to figure the best gauge wire to run to it...

Introducing particle width via the Breit-Wigner propagator can break gauge invariance. Anyone know of some "nice" way to incorporate widths while still retaining gauge invariance?

[SOLVED] Gauge Pressure A garden hose is attached to a water faucet on one end and a spray nozzle on the other end. The water faucet is turned on, but the nozzle is turned off so that no water flows through the hose. The hose lies horizontally on the ground, and a stream of water sprays...

In a screw gauge, the pitch is defined as the distance traveled in one rotation. Is it also equal to the length of one main scale division? If the length of one main scale division is not given, then can we take it to be equal to the pitch? Or do we take it as equal to some other default value.

I have been reading about string theory, most recently about twistor string theory. I think that I have a basic understanding, but certainly am no expert. The helix is an important structure in transmitting information of various types: - music theory mathematics [wave and matrix] - only...

Suppose A1 and V1 satisfy the coulomb gauge and A2 and V2 satisfy the lorentz gauge. what function S will transform A1 and V1 to A2 and V2? What function W will transform A2 and V2 to A1 and V1?l

http://arxiv.org/abs/math.DG/0511710 Higher Gauge Theory John C. Baez, Urs Schreiber 10 figures Differential Geometry; Category Theory "Just as gauge theory describes the parallel transport of point particles using connections on bundles, higher gauge theory describes the parallel...

I put this in the field theory section as its a gauge theory but it might just as well be in the GR section... Has anyone heard of this. http://citebase.eprints.org/cgi-bin/fulltext?format=application/pdf&identifier=oai:arXiv.org:gr-qc/0309041 Its apparently a renormalizable quantum...

Early history of gauge theory---a science history paper one way to enrich one's understanding of scientific theories is to learn about the people who discovered them and what they were thinking about at the time, and how other scientists reacted etc. gauge theory apparently got started in...

1. Why Nickel has got negative gauge factor? 2. What effect it will have when we use these materials in strain gauges?

My aim is to derive the photon propagator in an arbitrary gauge. I follow Itzykson-Zuber Quantum Field Theory and start from the Lagrangian with gauge-fixing term: {\cal L}(x) = -\,\frac{1}{4}\,F_{\mu\nu}(x)F^{\mu\nu}(x) - \,\frac{1}{2\xi}\,(\partial_{\mu}A^{\mu}(x))^2 I get the following...

A barrel contains a layer of oil of thickness 0.110 m floating on water of depth 0.245 m. The density of the oil is 630 kg/m^3 a) What is the gauge pressure at the oil-water interface? b) What is the gauge pressure at the bottom of the barrel? ** a) Atmospheric Pressure + Pressure...

I wanted to restart this discussion b/c the previous thread got sidetracked, and something about it has left me deeply confused, and I think my confusion is similar to the original posters confusion. In Wigners theory, particles (like say an electron) are unitary irreducible representations...

Dear friends I am here with mathematical physics question: we know tha if i have a compact Lie group G with g its Lie algebra, and a connection A on the fibre, For nonabelain Lie algebra The relation between covariant derivative and the curvature of A is [ tex...

Could someone please give me some references or the name of the theory for gauge theories using 'nice' gauge transformations, eg. transformations whose first derivatives in space are bounded? Why I ask that: my question is if we shouldn't take essential properties of quantum mechanics more...

Hello all, from Marlon's journal, I read the question "DO YOU KNOW WHY FORCE CARRIERS ARE ALWAYS BOSONS ? WHY DON'T WE HAVE GAUGE FERMIONS ?" Can anyone answer this question? :redface:

This is my (limited) understanding of particle physics: In particle physics gauge symmetries play an important role. To allow for massive gauge bosons this symmetry is broken. The theory of weak interactions can be derived from a local SU(2) symmetry, and quantumchromodynamics from a local SU(3)...

While exploring a sunken ocean liner, the principal researcher found hte absolute pressure on the robot observatino submarine at the level of the ship to be about 413 atmospheres. The density of seawater is 1025-kg/m^3. Calculate the gauge pressure p_g on the sunken ocean liner...

Can someone please attempt this problem? Question: A tall cylinder with a cross-sectional area of 12.0 cm^2 is partially filled with mercury; the surface of the mercury is 5 cm above the bottom of the cylinder. Water is slowly poured in on top of the mercury and the two fluids don't mix...

Gauge pressure question - please help I came across this multiple choice question while revising for my exams but I can't get any of the chioces. I've spent over an hour on this but can't figure out. Can someone please help me because it's starting to annoy me. What is the gauge pressure at...

what do these terms have to do with each other? yang mills gauge theory 't hooft instanton

In a bourbon distillery plant, the refined product, approximated as 40% by weight ethanol, 60% by weight water, is pumped through a plumbing system. At the OUTLET, where the inner diameter of the pipe is 5.08cm, the product fills an aluminum open cylinder (Diameter .442m, height 1.26m) in 98.9...

I have been going over this problem for at least 3 hours now, without any sign of improvement. I was wondering if you guys could at least point me in the direction of something I missed. Problem: At a certain point in a horizontal pipeline, the water's speed is 2.50 m/s and the gauge pressure...

How does a non-abelian gauge symmetry lead to asymptotic freedom for quarks?

Hi all, I'm currently doing some work trying to optimize coils (basically a large center hole solenoid) for a series of experiments. Two of the variables I'm going to be able to adjust are wire gauge of the coil and amperage through the coil. Online, I have found 'rule of thumb'...

I'm searching informations about the Gauge simmetries and their application in physics; where can i search in internet and where on books? thanks for answers

(--Planning Exercise - Strain gauge Coursework Help!--) Hi I've been stuck for several days in the early stages of my coursework i would have asked my tutor but I have been forced to stay home due to a very bad chest infection :frown: I will first provide a full transcript of the question...

If it's complex how could one calculate the 2 points function of A(+) and A? Thanks

A straight horizontal pipe with a diameter of 1.0 cm and a length of 50 m carries oil with a coefficient of viscosity of 0.12 N · s/m2. At the output of the pipe, the flow rate is 9.0 10-5 m3/s and the pressure is 1.0 atmosphere. Find the gauge pressure at the pipe input I used the formula...

Okay, this is not for homework, just curious. I was at a friends this weekend and he had a Galileo temperature gauge. I was trying to figure it out. It is full of glass bubbles that are half full of liquid, some small, some large, with glass weights at the bottom and markers. As the...

In trying to get my head round GR and quantum gravity, I'm puzzled about the following questions: Is the gauge group for gravity defined as the group of all possible Weyl tensors on a general 4D Riemann manifold? How is this group defined in matrix algebra? Is it a subgroup of GL(4). How do...