New type of accelerator

GCNRevenger · 2004-11-13 09:33:46

You still aren't even thinking about them properly Errorist.

Photons do not behave by the rules of normal things. You can't use normal physics to describe them or use them. These things just don't behave according to the rules you want them to, trying to harness their momentum to accelerate other things is like a square peg in a round hole.

The photon doesn't "achieve" the speed of light because it never accelerated in the first place, from the first instant that the photon was formed, it was already traveling at the speed of light. It doesn't even exsist at slower speeds (for its medium).

You use Max Plank's constant I believe, if memory serves, and multiply by the frequency of the photon's wave nature, to find how much energy is needed to produce that particular photon.

Again, you should not be thinking about your engine. You really shouldn't, because its all about the thermodynamics. Since there is no trick you can do to generate more propulsive energy then you put into the engine, it doesn't matter how good your engine is at all. Its all about how you intend to power it, where you get the energy from.

ERRORIST · 2004-11-13 19:31:52

I don't look at it as a trick but rather something yet to be discovered. From the instant a photon is produced from an almost still object it accelerates away from the source at C. We can't measure the acceleration rate from the newborn photon as of yet because we have not discovered yet how to do it.Look at the stars out in space Light years away. The photons from them were born many years ago but yet they still arrive at Earth for our viewing pleasure.They have yet to slow down. How much energy does it take to produce a given photon from its source and then have it accelerate @ C?

John Creighton · 2004-11-13 19:54:25

I don't look at it as a trick but rather something yet to be discovered. From the instant a photon is produced from an almost still object it accelerates away from the source at C. We can't measure the acceleration rate from the newborn photon as of yet because we have not discovered yet how to do it.Look at the stars out in space Light years away. The photons from them were born many years ago but yet they still arrive at Earth for our viewing pleasure.They have yet to slow down. How much energy does it take to produce a given photon from its source and then have it accelerate @ C?

Some people believe that matter is a standing wave. What we observe as velocity is group velocity and not phase velocity. In this view acceleration is thus more a change in frequency then velocity.

ERRORIST · 2004-11-13 20:22:15

Frequency that radiates outward at C in one direction. The particle is traveling faster than C. It has to be traveling faster than C because the true distance it has traveled is much greater because of the peaks and vallies in the wave.We measure the distance the particle has traveled but we discount the peaks and vallies of the wave which means it had to travel a farther distance when added up.

John Creighton · 2004-11-13 21:40:06

A spherical wave can actually be expressed as a distribution of plane waves. The wave does not express how fast the photon moves it only express how fast the wave function propagates. The wave function dictates the probability of finding a photon in a given region of space. You cannot exactly measure how fast a photon traveled due to the uncertainty principle. The peaks and values of the wave function have nothing to do with the trajectory of the wave. The only have to do with the intensity of the wave which is related to the probability of finding a photon in a given region of space. Anyway this thread is not about quantum physics and I am no expert. Start thinking about thermal dynamics and then you will know what you can and cannot do with rockets.

GCNRevenger · 2004-11-14 00:07:36

I don't look at it as a trick but rather something yet to be discovered. From the instant a photon is produced from an almost still object it accelerates away from the source at C. We can't measure the acceleration rate from the newborn photon as of yet because we have not discovered yet how to do it.Look at the stars out in space Light years away. The photons from them were born many years ago but yet they still arrive at Earth for our viewing pleasure.They have yet to slow down. How much energy does it take to produce a given photon from its source and then have it accelerate @ C?

Ohhhh I get it now... So, your engines are based on fantesy! Now it makes much more sense

Errorist, until there is evidence to the contrary, all your thinking about things "not yet discoverd" is pure wishful thinking. Utter nonsense. Science fiction. You are bound, bound by the laws of physics which are true until they are proven not to be, and the laws we have now have withstood a century of questioning and inquisition.

High among these laws are Einstein's theory of relativity and the laws of thermodynamics, which when taken together tell us somthing, they tell us that a photon cannot travel slower then the speed of light within its medium.

When and where does this apply? Everywhere and always! That means from the first instant the photon exsists until the last instant it exsists, so you see, it CAN'T accelerate because it was never stationary to begin with! It isn't that we can't measure the acceleration, its that there ISN'T ANY. You are quite simply wrong, completly and irreconcilably wrong. Since the laws of physics demand it, and no experiment has shown evidence to the contrary even with our femtosecond lasers, you have no legs to stand on but to wish real hard and "believe."

What you "think" and baselessly wish for, a photon that behaves according to normal particles, is a fairy tale... And tall tales have no business in science.

John Creighton · 2004-11-14 09:19:50

Dumb thought of the day ??? Maybe errorsist is partly right about the acceleration of photons. Maybe the waves caring the photons travel slower when near a particle kind of like they travel slower in diamond. As the wave propagates away its speed increases. Of course non of this has anything to do with rockets.

GCNRevenger · 2004-11-14 09:35:59

No John, because the waves don't carry the photons. The waves ARE the photons. Plus, when light reaches an interface between two substances, the change in the velocity is instantainous, light just doesn't behave like normal things.

John Creighton · 2004-11-14 09:51:48

No John, because the waves don't carry the photons. The waves ARE the photons. Plus, when light reaches an interface between two substances, the change in the velocity is instantainous, light just doesn't behave like normal things.

Is the boundary really discontinuous or do we approximate it as discontinuous just because it makes our math easier. The wave function PHI is defined so that (PHI)PHI*
(where * denotes complex conjugate) is the probability of finding a photon in a given region of space. When I say the wave carries the photon I mean it caries the probability distribution which dictates our chances of finding the photon. Also waves and photons are not the same thing. The both model different behaviors of light.

chat · 2004-11-14 16:27:27

GCNRevenger,

Still the photon has a duality problem.
It can be measured as a wave and a particle.

My thought is that a photon is neither a wave or a particle, it is a boundary and measure of time.
When we measure a photon we simply measure either the time wave or time dilation as a particle.

This also answers a black hole bending light, in effect altering light speed for light.

The black hole doesn't effect the light, but the time in its gravity wave that the light becomes part of.

The only reason the photon exists to us at all is the fact that we are not traveling at C, at C the universe has no dimensions and no time.

Light always travels at C because faster doesn't exist in this universe, and slower than time is what light cant travel to remain as light.

Even though the life of a photon might be a trillionth of a second, that trillionth of a second lasts forever in a universe with no time and space.

Just my thoughts though

ERRORIST · 2004-11-14 23:45:43

The book Fundamentals of physics second edition by Halliday and Resnick talks about the billiard-ball-like collisions of photons and electrons on page783. It states the follwing:

"We shall now describe the Compton effect, in which the key experiments occur in the X-ray and Gamma-ray regions of the electromagnetic spectrum. This effect, explained in billiard-ball- like collisions between photons and electrons, provides convincing evidence of the particle-like nature of of light. Its explaination requires that not only the energy but also the linear momentum of a light beam be concentrated in photons."

John Creighton · 2004-11-14 23:50:10

Its explaination requires that not only the energy but also the linear momentum of a light beam be concentrated in photons."

If you want to think of it that way fine but light does not always behave as a particle.

For instance see the double slit experiment.

ERRORIST · 2004-11-14 23:58:22

Furthermore, the book explains the following on page 784 bottom and 785 top:

"Figure 42-12 shows a collision between photon and an electron, the electron assumed to be initially at rest and essentially free,that is, not bound to the atoms of the scatterer. Let us apply the law of conservation of energy to this collision. Since the recoil electrons may have a speed v that is comparable with that of light, we must use the relativistic expression for the kinetic energy of the electron. From the conservation of energy principle we may write:

hv=hv'+(m-mo)c2

in which the the second term on the right is the relativistic expression for the kinetic energy of the recoiling electron. m being the relativistic mass and mo the rest mass of that particle.

Oh, and no TRICK is involved here either.

GCNRevenger · 2004-11-15 07:18:32

NO Errorist, the "trick" is your continued and unstoppable search for a trick to defeat the thermodynamics. The thermodyamics is everything, and you have to address that first.

The conservation of energy states and demands that you cannot possibly get more propulsive energy out of an engine then you put into it. In this instance, the "Compton Engine" cannot EVER make more propulsive kenetic energy then you put in energy to feed the laser... which will have a titanic energy consumption just like your relativistic proton engine.

And if you had actually understood what your book was talking about, you would have figured out that the photon DOES NOT slow down following electron "collision," so therefore it is not a "collision" at all. Halliday and Resnick are simply showing you how it is analgous.

ERRORIST · 2004-11-15 08:37:25

That is the beauty of it the photon will continue on to stike another electron.Not only do they call it a collision they refer to it as a billiard-ball-like collision. You refuse to understand. Why?

John Creighton · 2004-11-15 09:13:38

That is the beauty of it the photon will continue on to stike another electron.Not only do they call it a collision they refer to it as a billiard-ball-like collision. You refuse to understand. Why?

However if the photon gives kinetic energy to the electron the photon will loose energy by changing to a lower frequency.

GCNRevenger · 2004-11-15 09:19:52

No Erroist, you continuously refuse to conform your thinking to the very most basic and fundimental concepts of thermodynamics. You can NEVER make a machine, no matter what you do or trick your try, that can extract more energy then you put into it. Never. Such an engine would have no more chance of working then Ant's gravity wheel.

In this case, the physics behaves "like" a billard ball collision because the math works for it. Thats all. Not because a collision is actually occuring in the classic sense. If a photon strikes an electron and the electron gains energy, then the photon WILL lose energy. It will either lose this energy by a reduction in the frequency of its wave behavior or it will simply cease to exsist and be absorbed. Note that the reradiated photon never slows down, it is still traveling at the speed of light, but now has less energy.

In either event, the photon will require energy to create, and then some or all the photon's energy will be converted to kenetic energy of the electron, but then the photon has less or even zero remaining energy.

GCNRevenger · 2004-11-15 09:38:39

In fact, real physists and engineers use the conservation of energy as a litmus test if their idea is stupid or not... if it violates it, then it must be wrong.

Your engine violates it, so it must be wrong too.

You can't make 2+2=5 no matter what you do.

ERRORIST · 2004-11-15 11:28:40

I agree but you can transfer conserved energy in this example of photon electron collisions.

GCNRevenger · 2004-11-15 12:16:57

You can transfer energy from the photons to the electrons in a "Compton Accelerator," but the photons will lose energy or be destroyed in the process. Now we have come again full circle, back to the thermodynamics, that you cannot get more propulsive kenetic energy from the accelerated electrons then what you put in the laser to push them. As previously stated, an electron engine will not be practical reguardless how you accelerate the electrons.

ERRORIST · 2004-11-15 13:02:09

So how is it that a less massive photon moving at C can accelereate the much more massive electron from a near rest state to near the same velocity as the very photon that hit it?

GCNRevenger · 2004-11-15 13:06:37

It doesn't. Like a BB hitting a battleship, the battleship won't reach the same speed that the BB did that struck it. You could hit the electron with a very large number photons and that would get you close, but the amount of energy needed - like usual - would be vast.

ERRORIST · 2004-11-15 13:34:20

This is not what the physics book says. They equate one photon per electron per collision.

John Creighton · 2004-11-15 13:42:33

This is not what the physics book says. They equate one photon per electron per collision.

GCNRevenger was talking about multiple collisions. I think you can have more then two photons hitting an ellectron at the same time but that is a different issue.

GCNRevenger · 2004-11-15 13:50:52

There are two possibilities, either the book is talking only about energy change in which case you aren't understanding it, or you are way way off and going on a tangent again. In either event, what the book says or what you think the book says doesn't apply. If it did, it would violate the conservation of energy and/or relativity, which it cannot.

Since these rules cannot be wrong, then the only possible conclusion is that you are Errorist.

You can strike an electron with multiple photons sequentially and increase its energy to near the speed of light, but you have to get alot of energy to make the photons so this is not a trick to cheat the conservation of energy.

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#101 2004-11-13 09:33:46

Re: New type of accelerator

#102 2004-11-13 19:31:52

Re: New type of accelerator

#103 2004-11-13 19:54:25

Re: New type of accelerator

#104 2004-11-13 20:22:15

Re: New type of accelerator

#105 2004-11-13 21:40:06

Re: New type of accelerator

#106 2004-11-14 00:07:36

Re: New type of accelerator

#107 2004-11-14 09:19:50

Re: New type of accelerator

#108 2004-11-14 09:35:59

Re: New type of accelerator

#109 2004-11-14 09:51:48

Re: New type of accelerator

#110 2004-11-14 16:27:27

Re: New type of accelerator

#111 2004-11-14 23:45:43

Re: New type of accelerator

#112 2004-11-14 23:50:10

Re: New type of accelerator

#113 2004-11-14 23:58:22

Re: New type of accelerator

#114 2004-11-15 07:18:32

Re: New type of accelerator

#115 2004-11-15 08:37:25

Re: New type of accelerator

#116 2004-11-15 09:13:38

Re: New type of accelerator

#117 2004-11-15 09:19:52

Re: New type of accelerator

#118 2004-11-15 09:38:39

Re: New type of accelerator

#119 2004-11-15 11:28:40

Re: New type of accelerator

#120 2004-11-15 12:16:57

Re: New type of accelerator

#121 2004-11-15 13:02:09

Re: New type of accelerator

#122 2004-11-15 13:06:37

Re: New type of accelerator

#123 2004-11-15 13:34:20

Re: New type of accelerator

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