lightspeed

[Moontanman]

Originally Posted by goku

reality?
maybe i dumded it down a little too much
my reality says one doesn't just start increaseing mass

Neither does mine, unfortunately our reality changes drastically as the speed of light is approached. This can be proved in particle accelerators. Charged particles are much easier to accelerate than people or space ships and when they approach the speed of light all the changes that have been described to you in this thread take place. They become more massive, harder to accelerate and shorter along the direction of acceleration and time slows down for them.

i reckon if the particles of your thrust (exhuast gasses, or what ever) do not travel at or beyond light speed you may not acheive light speed

Actually the acceleration does not depend on the speed of your exhaust, acceleration is cumulative, You can go faster then your exhaust. The effects of trying to go to or faster than the speed of light are indeed real.

has anyone ever actually tried to go light speed?

Our civilization does not have the power out put necessary to approach the speed of light as individuals or space craft but as I pointed out we have and can routinely accelerate charged particles to speeds near the the speed of light and the effects I have described do take place. There are also the effects pointed out by DI5STURBED

Originally Posted by DI5STURBED

A useful tool, I've found:
Perihelion precession of Mercury
Deflection of light by the Sun
Gravitational redshift of light
Post-Newtonian tests of gravity
Gravitational lensing
Light travel time delay testing
Gravitational redshift
Frame dragging tests
Gavity Probe B
(and many more)

[goku]

i've been thinking about those particle accelerators, i know it's been a while but the thought just came to me the other day, they're built in a circle right?

there's your problem

[Pyrotex]

goku,
I'm sure you remember me.
It would seem that you might possibly be engaging in prevarication.
This is a rather rude thing to do with honest folk who only want to teach and explain.

Yes, Mankind is currently accellerating things to within 99.99% of the speed of light. Those "things" are currently nuclear particles such as protons and electrons. And they DO become more massive as they approach the speed of light.

Accellerating the particles in a circle is a great convenience -- otherwise we would have to build linear ("straight line") accellerators too long to fit on a continent. The fact that the particles go in a circle makes no difference to any of the arguments that have been presented so far.

Measuring the mass ("inertial mass") of a particle is rather easy. One way is to allow the particle to impact a target, say a number of thin layers of gel, and count how many layers the particle penetrates.

It should be noted that Einstein's equation that relates the mass of a particle to its velocity, should be interpreted very carefully. (We'll keep this simple) His equation predicts the "observed" mass of a particle (or spaceship) from the viewpoint of a "stationary" observor. The scientist (or grad student) will measure that the particle does indeed increase in mass the faster it goes.

This does NOT say that the particle retains this extra mass after it comes to rest again. In fact, the particle returns to its original mass in this case.

This does NOT say that the particle "experiences" a gain in mass. If we switch to the example of an astronaut in a spaceship, though WE will observe the astronaut to have a mass measuring in many TONS when he is speeding away at 99.9% of the speed of light, HE will experience his own mass as not changing at all. If he looks back at the grad student on the Earth, he will observe the grad student as having a mass of many TONS.

Graduate students all over the world, and in every language, conduct experiments to test Einstein's theory every year. And every time, in every year, they prove that Einstein was correct.

If this doesn't make sense to you, then perhaps there are either limits to your ability to understand, or limits to your willingness to understand.

But the truth stands on its own.

[goku]

Originally Posted by Pyrotex

goku,
I'm sure you remember me.
It would seem that you might possibly be engaging in prevarication.
This is a rather rude thing to do with honest folk who only want to teach and explain.

i don't know what you're talking about there, but yes i remember you

and you missed my point, but does anyone else want to take a jab at post #22 before i elaborate?

[Moontanman]

Originally Posted by goku

i've been thinking about those particle accelerators, i know it's been a while but the thought just came to me the other day, they're built in a circle right?

there's your problem

Goku! Good to have you back, I've missed your moronic ambush posts, it's apparent that you back up to snuff and in your normal fine form, keep it up, suspension can only be a few more posts away

[CraigD]

Originally Posted by goku

i've been thinking about those particle accelerators, i know it's been a while but the thought just came to me the other day, they're built in a circle right?

Some are, some are not. A particle accelerator that’s built in a straight line is called, sensibly enough, a linear particle accelerator. A famous, and the longest one is the 3.2 km (2 mile) one at the SLAC, which can accelerate electrons and positrons to about 0.99 times the speed of light. It found slew of quarks and other theoretically predicted particles from the ‘70s through the ‘90s, leading to a few Nobel prizes for its users.

Impressive as linear accelerators like the SLAC’s are, they’re limited in that the distance over which they can accelerate particles is the same as their length. Scaling a linear accelerator up to the length necessary for the particle speeds needed for today’s experiments quickly results in something longer than will fit on earth, requiring more expensive engineering material and construction than there is on earth. So higher energy accelerators are built in circles, allowing the same stretch of machinery to accelerate each particle many times. The biggest one yet is the 27 km (17 mile) diameter LHC, which can accelerate protons to about 99.9999991 times the speed of light.

Originally Posted by goku

there's your problem

There are some problems with circular particle accelerators not encountered with linear ones, a major one being that they constantly emit synchrotron radiation, making them less energy efficient than linear accelerators, requiring heavily shielded (usually solved by burying them), and must have their detectors situated in a way to not be interfered with by unwanted radiation. However, having been building these things for many decades, these engineering problems have been pretty well solved, so that nowadays the major engineering challenges are simply putting more and more energy into the accelerated particles.

In addition to the links above, a good starting place to read about particle accelerators is the wikipedia article “particle accelerator”.

[goku]

the thought i had was the amount of centrifical force being applied to the particale.
the faster you go, more centrifical force is applied
and i assume a greater amount of energy is needed to keep the particle from running into the gard rail

[goku]

Originally Posted by Moontanman

Goku! Good to have you back, I've missed your moronic ambush posts, it's apparent that you back up to snuff and in your normal fine form, keep it up, suspension can only be a few more posts away

accually i do dip snuff,
ambush? our diffinitions of ambush must somewhat, differ

just wandering if anyone else had the same thought

[Pyrotex]

Originally Posted by goku

i've been thinking about those particle accelerators, i know it's been a while but the thought just came to me the other day, they're built in a circle right? there's your problem

No. It isn't a problem.

The following is a summary from the Wikipedia entry.

Back in the early 1900's, the first linear accellerators were built, most no longer than a few inches. In the 1920's universities in America and Europe began building quite a few linear accellerators, ranging in length from a few feet, to a kilometer or more. The longest in the world is the Stanford Linear Accelerator, SLAC, which is 3 km long.

In the meantime, the earliest circular accelerators, cyclotrons, were invented in 1929. There was one small problem with the cyclotrons: making the particles travel a curved path caused the particles to emit energy (as photons). In other words, the particles lost a little bit of their energy on each circuit. So universities began building larger cyclotrons, up to several km in diameter, because the larger the circle, the smaller the loss of energy.

The bottom line is this: when you subtract the energy loss from cyclotrons and their more modern circular cousins, the particles accellerate -- and are observed to gain mass -- in exactly the same way for both kinds of accellerator.

The particles in linear and circular accellerators behave the same. They both gain mass at exactly the rate predicted by Einstein.

This verification between two different types of machines demonstrates beyond any doubt that the measurements made in circular accellerators is valid. No problem.

Now stop being so snarky. If all you really want to do is tease the physicists here, then it will be a trivial matter to have you excluded. If you want to learn about modern science, you're in the right place.

[CraigD]

Originally Posted by goku

the thought i had was the amount of centrifical force being applied to the particale.
the faster you go, more centrifical force is appied

The right term is centripetal force, but you’re essentially right. If not for this force, the particle wouldn’t follow a circular path.

If the acceleration were due to an electrostatic force, such as gigantic accumulation of opposite charge in its center, no energy would be required. Energy = Work = Force x Distance, so if the radius of a body traveling in a circle is unchanged, Energy = Work = Force x 0 = 0. This is why planets orbiting stars and moons and satellites orbiting planets don’t “run down”, and why, if it has a good bearing, even a heavy, fast-turning wheel turns for a long time.

This is not, however, how circular particle accelerators keep charged particles traveling in a circle. They do it with a magnetic field perpendicular to the particles’ direction of motion. When a charged particle passes thought such a magnetic field, it’s deflected. Surprisingly, rather than making circular particle accelerators more difficult to design and build, it makes them easier. An explanation is more than I think this post should attempt, so for details, check out a textbook or online reference like the wikipedia article “cyclotron”.

Originally Posted by goku

and i assume a greater amount of energy is needed to keep the particle from running into the gard rail

For the somewhat complicated reasons I touch on above, the strength of the magnetic field need to deflect the particles, and thus the power needed to produce the field, doesn’t depend on the speed of the particles. However, the faster the particles travel, the greater their loss of energy and speed, requiring more power to accelerate them in their direction of travel. Thus a giant accelerator like the LHC requires a huge amount of power – around 180 MW (a quarter million horsepower), about the same as the largest aircraft carrier afloat, or 14% of the total power used by all of Geneva. Not all of this power goes into accelerating particles. Roughly half is needed to run the refrigeration system that keeps its electromagnets chilled to superconductive temperatures.

When it comes to the actual collision experiments accelerators that are the main purpose of particle accelerators, it doesn’t matter if the particles were accelerated by a linear or a circular accelerator, because the particles aren’t accelerated in any way in the region of the collision target.