Occupations

[Nance]

WHAT???????????????????

 

[c9zx]

http://neutrons.ornl.gov/facilities/SNS/

Easier to post a link than explain

So does your car have half integer spin or integer spin?

Chuck

Nobody really knows what spin is, much beyond the fact that it is an

attribute of an elementary particle. Charge, mass, speed, energy, and angular momentum are among other attributes. You've probably noticed that some of these attributes are intrinsic to the particle and can't be changed (e.g., mass, charge), while others can be gained and lost (e.g., speed, angular momentum). Spin is actually

two attributes, one of which is intrinsic, the other of which can be

gained or lost.

More about this later.

Although we do not have a deep understanding of what spin is, we do have a mathematical description of how it behaves -- in particular, of how the total spin of a system of particles depends on the spins of the constituents. This allows us to compare spin's behavior to the behavior of other things that we feel we understand better. One thing

we have noticed is that spin behaves a lot like angular momentum (which also is really two attributes).

Angular momentum is a vector quantity (something that has both a magnitude and a direction, like velocity) that can take on only certain values in quantum mechanics. Think of angular momentum as an arrow of some length that can point in different directions, but you cannot ever have complete information about the direction. In particular, if you have measured the projection of the arrow along the z axis, you have

gained a clue about what the total angular momentum might be, but you have also destroyed any information you might have had about its projection along any other axis.

Another thing we know about angular momentum is that, in quantum

mechanics, it cannot take on just any old values, but only certain specific ones. If a particle has three units of total angular momentum, then its projection can be any of (-3, -2, -1, 0, 1, 2, 3) and that is it: projections must differ by an integer number of units. Very weird, but quite

a handy fact: if you know that a particle's angular momentum can take on only two different projection values, then you know its total angular momentum must be 1/2, and the projection values are (-1/2, 1/2). If you know there are three projection values, then you know the

total angular momentum is 1, with projections (-1, 0, 1).

Spin acts like this, so everything you've just learned about angular

momentum is also true of spin. In fact the mathematical description of the way spin behaves is so similar to the math of angular momentum that we can even do a mathematical trick that allows us to

pretend that spin and angular momentum can be added together. However, the magnitude of the spin quantum number is an intrinsic attribute of a particle. All electrons have total spin 1/2, with two possible projection values, as we've seen. The projection can be changed, but the total spin of 1/2 is fixed for all time. It is part of the

definition of an electron. All photons have spin 0, and for them "projection" does not seem to make much sense, but it is

clear anyway that the number of possible projection states is one.

A curious and very mysterious thing is that the quantum mechanical rules for particles that have integer spin are very different from the rules for particles with half-integer spin.

All the half-integer particles (e.g., electron, proton, neutron) must be

distinguishable from each other: if they are in the same system, they must differ in at least one quantum number.

Not so for the integer-spin particles (e.g., photon, meson, gluon). These are allowed to be indistinguishable, and they can all have the same quantum numbers including position. It so happens that particles with half-integer spin are the particles we think of as making up matter,

and the particles with integer spin are those we associate with forces.

Why spin should be the thing that distinguishes stuff from the forces between stuff is unfathomable to me, and that spin

should do this in such an apparently arbitrary way (half-integer as

opposed to integer) suggests to me that our understanding is fundamentally flawed, and that the real answer to your question

-- if we ever discover it -- will be part of a deeper understanding of

/way/ more than spin.

I thought I might get a technical response to my lame attempt at physics based humor, and a good response it is! I was just having some fun. I hope you took no offense.

Chuck A.K.A. duality personality

 

[Tnfastbk]

http://neutrons.ornl.gov/facilities/SNS/

Easier to post a link than explain

So does your car have half integer spin or integer spin?

Chuck

Nobody really knows what spin is, much beyond the fact that it is an

attribute of an elementary particle. Charge, mass, speed, energy, and angular momentum are among other attributes. You've probably noticed that some of these attributes are intrinsic to the particle and can't be changed (e.g., mass, charge), while others can be gained and lost (e.g., speed, angular momentum). Spin is actually

two attributes, one of which is intrinsic, the other of which can be

gained or lost.

More about this later.

Although we do not have a deep understanding of what spin is, we do have a mathematical description of how it behaves -- in particular, of how the total spin of a system of particles depends on the spins of the constituents. This allows us to compare spin's behavior to the behavior of other things that we feel we understand better. One thing

we have noticed is that spin behaves a lot like angular momentum (which also is really two attributes).

Angular momentum is a vector quantity (something that has both a magnitude and a direction, like velocity) that can take on only certain values in quantum mechanics. Think of angular momentum as an arrow of some length that can point in different directions, but you cannot ever have complete information about the direction. In particular, if you have measured the projection of the arrow along the z axis, you have

gained a clue about what the total angular momentum might be, but you have also destroyed any information you might have had about its projection along any other axis.

Another thing we know about angular momentum is that, in quantum

mechanics, it cannot take on just any old values, but only certain specific ones. If a particle has three units of total angular momentum, then its projection can be any of (-3, -2, -1, 0, 1, 2, 3) and that is it: projections must differ by an integer number of units. Very weird, but quite

a handy fact: if you know that a particle's angular momentum can take on only two different projection values, then you know its total angular momentum must be 1/2, and the projection values are (-1/2, 1/2). If you know there are three projection values, then you know the

total angular momentum is 1, with projections (-1, 0, 1).

Spin acts like this, so everything you've just learned about angular

momentum is also true of spin. In fact the mathematical description of the way spin behaves is so similar to the math of angular momentum that we can even do a mathematical trick that allows us to

pretend that spin and angular momentum can be added together. However, the magnitude of the spin quantum number is an intrinsic attribute of a particle. All electrons have total spin 1/2, with two possible projection values, as we've seen. The projection can be changed, but the total spin of 1/2 is fixed for all time. It is part of the

definition of an electron. All photons have spin 0, and for them "projection" does not seem to make much sense, but it is

clear anyway that the number of possible projection states is one.

A curious and very mysterious thing is that the quantum mechanical rules for particles that have integer spin are very different from the rules for particles with half-integer spin.

All the half-integer particles (e.g., electron, proton, neutron) must be

distinguishable from each other: if they are in the same system, they must differ in at least one quantum number.

Not so for the integer-spin particles (e.g., photon, meson, gluon). These are allowed to be indistinguishable, and they can all have the same quantum numbers including position. It so happens that particles with half-integer spin are the particles we think of as making up matter,

and the particles with integer spin are those we associate with forces.

Why spin should be the thing that distinguishes stuff from the forces between stuff is unfathomable to me, and that spin

should do this in such an apparently arbitrary way (half-integer as

opposed to integer) suggests to me that our understanding is fundamentally flawed, and that the real answer to your question

-- if we ever discover it -- will be part of a deeper understanding of

/way/ more than spin.

I thought I might get a technical response to my lame attempt at physics based humor, and a good response it is! I was just having some fun. I hope you took no offense.

Chuck A.K.A. duality personality

Not at all cut and paste does wonders

 

[72HCODE]

 

[c9zx]

Sometimes, not often. Mostly a gear head mentality tempered with a healthy dose of reality.

Chuck

 

[Tnfastbk]

Sometimes, not often. Mostly a gear head mentality tempered with a healthy dose of reality.

Chuck

How funny

 

[bkelley]

I work part time at a rec center as a program assistant. I'm usually a life guard for the skate park we have but if no one is skating I get to go inside and hang out with all the kids. It's pretty cool because most of the day I am playing basketball, football, kickball or something and getting paid for it. I also major in electronic engineering and minor in mechanical engineering here at the local university which takes up the rest of my time.

 

[72fastback]

Well. Here are a few pics of what I can do with stainless steel and a grinder. I skipped a few steps in the pictures because the difference is not that visible in the pictures.

 

[Maiden Dearborn]

Occupation? I thought chief mechanic and head rust remover of the mustang was my occupation. Actually, I'm one of those statistics that was given and involuntary resignation from my real employer and put on the unemployment rolls.

So I've gone from having money and no time to work on the car to having way too much time and not enough money to work on the car. So far, sand paper is cheap and elbow grease is stocked up in my garage.

For those of you that have a real paying job and are paying taxes, thankyou. Looking? you bet. I spend four hours a day looking, however, the market for engineers with master's degree and 25 years of experience seems to have dried up some time ago.

 

[TommyK]

Tommy,

I have a similar build to yours in my '73 Grande, except I am using the Edelbrock cam (234/244) along with the Edelbrock 750 carburetor. I am also using a 3.50 gear with Traction Loc and big valve D0VE heads.

What made you decide to go with the FMX versus the C6? My C6 is beefed to the maximum and I still worry about all the torque I am putting out with the 472. What, if anything, did you do to the FMX to prepare for the Lima's output?

BT

Sorry I missed your question. I used the FMX simply because I wanted to get the car running and was to lazy to try and figure out the shifter mods/swap required to go to a C6 which I have sitting on the floor of the garage. I figured I would run the FMX until it blows up then make the swap. All I did to the FMX was a torque converter, a big cooler, fluid and filter. I have a transgo shift kit sitting on the bench but I haven't got around to installing it. Because the FMX has survived for 2 years without an issue, I am considering sending the valve body to Broader for reprogramming and continuing to run it. If Bad Shoe would make an FMX rebuild vid I would sell the C6.

 

[c9zx]

Well. Here are a few pics of what I can do with stainless steel and a grinder. I skipped a few steps in the pictures because the difference is not that visible in the pictures.

Amazing work! You need a mandrel bender and go into the header business. Chuck

 

[73vertproject]

Occupation? I thought chief mechanic and head rust remover of the mustang was my occupation. Actually, I'm one of those statistics that was given and involuntary resignation from my real employer and put on the unemployment rolls.

So I've gone from having money and no time to work on the car to having way too much time and not enough money to work on the car. So far, sand paper is cheap and elbow grease is stocked up in my garage.

For those of you that have a real paying job and are paying taxes, thankyou. Looking? you bet. I spend four hours a day looking, however, the market for engineers with master's degree and 25 years of experience seems to have dried up some time ago.

Hang in there, Dearborn. By the time you plow through your stockpile of elbow grease and sandpaper, I'm thinking something will come through for you.

Doc

 

[71stang]

I have done CNC programing for the last 7 years, machinist for the last 17 years, got my 71 this year, wanted one since I was in High school since a girl friend had one.

 

[mach71351c]

I'm a truck driver for a local asphalt company. I did a 14 year sentence as a shop foreman at a ford dealer.

 

[mach1 fever]

i was a truck driver for 28 years , then a tool and die maker for 3 years. now im on disability and out of work because im what is called a brittle diabetic. means my diabeties cant be controlled. cant do as much as i used to to my cars but still love to tinker with them when i can.help son and friends when i can.

 

[BigPinoyHunk]

7 years now in the USAF, i deploy every 8-12 months!!! I'm an aircraft fuel system craftsman.

i gotta love the extra money when i deploy but its hard on the family though.

 

[Tnfastbk]

7 years now in the USAF, i deploy every 8-12 months!!! I'm an aircraft fuel system craftsman.

i gotta love the extra money when i deploy but its hard on the family though.

I know its Christmas but thank you for your service.

 

[73vertproject]

7 years now in the USAF, i deploy every 8-12 months!!! I'm an aircraft fuel system craftsman.

i gotta love the extra money when i deploy but its hard on the family though.

Haven't heard from you in a while, xoliex. Glad to see your post.

Doc

 

[tx-skydiver]

I am VP of Technology for a financial firm. Unfortunately I have many addictions to pay for. Mustangs are only one of them (but my favorite).

Currently have 4 of them. My 2007 GT, G/F's 2004 GT, 72 Mach I Q code (under resto), and 65 coupe (under resto). I almost bought another one today. Whew. Glad that didn't work out.

 

[DarkAzura]

I'm a college student who's becoming a Marine Reservist so I can finish school while I serve.