v > c for beta-rays?

*elias2010*

Hello, I repeat my question
As is well known that radioactive decay is a random, automatic phenomenon that nothing can stop it. This is unaffected by any variable such as temperature, pressure, acceleration. Each radioactive element has a specific fixed as half-life, wavelength and period, which is fully stable and unaffected.
Imagine a spaceship made of depleted uranium in the earth is moving at a speed approaching that of light.
B-rays emitted in the direction that moves beyond the speed of light?
No, says the special theory. But then is the paradox. A Geiger counter in the spacecraft detects radiation and another mounted on the outside 'in front of the window' was not detected. Both are stationary observers on the craft. To illustrate this, suppose that the craft is made of non-radioactive materials and moving towards earth with a constant speed. Inside there's a piece of uranium, a Geiger counter in front of A is in relation to the direction of craft speed and a second B behind it. If the speed is low, both counters detect radiation. Recall here that the speed of light is constant independent of the observer and inaccessible. So if the speed is equal to that of light, A did not detect radiation. Which of the two would happen if there was no earth or other reference point to know the speed? That is, whether the rings A or not, depends on the observer. The theory introduces a new conception of reality, where a natural phenomenon does not happen by itself, but depends on the existence of observers.
But you say, nobody can approach the speed of light. But perhaps one core of radioactive isotope in a large accelerator can do. You just have to try it, if there at CERN read our articles. We will see then if the speed prevents the decay of the nucleus, which is, as we said, a random phenomenon. And how the core 'knows' that moving relatively to the observer to 'postpone' its breakdown of?

Ich

The postulates of relativity:

1) principle of relativity means that there is no preferred state of motion, which directly means that the outcome of your rocket experiment is independent of its velocity.
2) speed of ligth the same in every reference frame means that there is no reference frame where the speed of light is zero as in your "So if the speed is equal to that of light, A did not detect radiation.". Which means again that the rocket can't go at the speed of light.

So, even without any math, your conclusions directly contradict the postulates that the theory is built on. You sure you're talking about relativity? Where did you learn it from?

As to your questions,

B-rays emitted in the direction that moves beyond the speed of light?

I don't understand what you're asking.

Which of the two would happen if there was no earth or other reference point to know the speed?

Already answered.

And how the core 'knows' that moving relatively to the observer to 'postpone' its breakdown of?

In the core's system, there is no time dilation. Time dilation is a relation between different frames, like core frame and laboratory frame. It has nothing to do with your notion of "slowing processes".

*elias2010*

I am not talking about time dilation,what I am asking for is that if the moving core decays,b-rays emmited beyond the speed of light?

Ich

You mean, kind of v(beta relative to earth) = v(rocket) + v(beta relative to rocket) > c?

Try this: http://en.wikipedia.org/wiki/Velocity-addition_formula

*elias2010*

Thank you,I'll see it,but what about the isotope core emission relative to lab?

Ich

Thank you,I'll see it,but what about the isotope core emission relative to lab?

Either the nucleus is going v<c, then you're talking about time dilation, which I already answered. Or it is going >=c, then you're talking about something impossible.

HallsofIvy

Quote by elias2010

Hello, I repeat my question
As is well known that radioactive decay is a random, automatic phenomenon that nothing can stop it. This is unaffected by any variable such as temperature, pressure, acceleration. Each radioactive element has a specific fixed as half-life, wavelength and period, which is fully stable and unaffected.
Imagine a spaceship made of depleted uranium in the earth is moving at a speed approaching that of light.
B-rays emitted in the direction that moves beyond the speed of light?
No, says the special theory. But then is the paradox. A Geiger counter in the spacecraft detects radiation and another mounted on the outside 'in front of the window' was not detected. Both are stationary observers on the craft. To illustrate this, suppose that the craft is made of non-radioactive materials and moving towards earth with a constant speed. Inside there's a piece of uranium, a Geiger counter in front of A is in relation to the direction of craft speed and a second B behind it. If the speed is low, both counters detect radiation. Recall here that the speed of light is constant independent of the observer and inaccessible. So if the speed is equal to that of light, A did not detect radiation. Which of the two would happen if there was no earth or other reference point to know the speed? That is, whether the rings A or not, depends on the observer. The theory introduces a new conception of reality, where a natural phenomenon does not happen by itself, but depends on the existence of observers.
But you say, nobody can approach the speed of light. But perhaps one core of radioactive isotope in a large accelerator can do. You just have to try it, if there at CERN read our articles. We will see then if the speed prevents the decay of the nucleus, which is, as we said, a random phenomenon. And how the core 'knows' that moving relatively to the observer to 'postpone' its breakdown of?

No one has said you cannot approach the speed- you just can't ever get there. And, no, the speed does not "prevent" decay of the nucleus. You are just using the wrong formula for combination of speeds. If an atom on a space ship, moving at, say, .9c relative to me, emits a beta ray moving at .9c relative to the atom, directly toward me, I would measure the beta ray as moving at
[tex]\frac{.9c+ .9c}{1+ \frac{(.9c)(.9c)}{c^2}}= \frac{1.8c}{1.81}= .99c[/tex]
still less than the speed of light.

DaleSpam

Quote by elias2010

B-rays emitted in the direction that moves beyond the speed of light?

Beta radiation consists of electrons or positrons. It is always slower than c.

If you believe otherwise then please provide a mainstream scientific reference which states that.

Whovian

Quote by DaleSpam

Beta radiation consists of electrons or positrons. It is always slower than c.

If you believe otherwise then please provide a mainstream scientific reference which states that.

I think what (s)he's saying is the very well known newtonian formula for adding velocities, which is invalid in this case.

*elias2010*

Thank you all
What I ask in my first question is that if A counter rings,is this for an observator on earth means that b-rays beyond the speed of light?

Whovian

Again, no, the formula isn't [itex]\vec{v}_{1,3}=\vec{v}_{1,2}+\vec{v}_{2,3}[/itex].

DaleSpam

Also, a Geiger counter does not measure speed of a radioactive particle, it only detects its presence. To measure speed you will need something else, like a Doppler radar.

Mentz114

Quote by elias2010

Inside there's a piece of uranium, a Geiger counter in front of A is in relation to the direction of craft speed and a second B behind it.

In this setup, the detectors are stationary wrt the source. Therefore they will both count beta rays at all times. Furthermore, every observer will agree on the counts.

Quote by elias2010

If the speed is low, both counters detect radiation.

No, this is wrong. The counters operation does not depend on a relative velocity with some other frame.

*elias2010*

Ok,but what about γ-rays also emitting by the nucleus?

Whovian

Quote by elias2010

Ok,but what about γ-rays also emitting by the nucleus?

Since those are light, they travel at c in all reference frames.

Remember that if we use the relativistic formula for adding speeds, if something's moving at c in one reference frame, it's moving at c in all reference frames (in fact, ignore the relativistic formula for adding speeds, this is what Special Relativity comes from), and if something's moving at <c in one reference frame, you get a speed of <c in all reference frames.

Mentz114

Quote by elias2010

Ok,but what about γ-rays also emitting by the nucleus?

As Whovian has said, γ-rays are light so they always travel at c in all frames.

If you placed your apparatus ( the emitter and the detectors ) in any non-accelerating lab it will give the same results. The laws of physics are the same in all inertial frames. You should be aware that there is no absolute motion. The lab may be moving close to c with respect to some other frame but that is irrelevant. In the lab frame there are no relativistic effects.

If the emitter was in motion with respect to the detectors, there would relativistic effects like time dilation, but the counts of the detectors would be the same in all frames, although the rate of detection might be different.

*elias2010*

Forgive me but I have doubts until this could be experimentally assured.I asked for it:
"But perhaps one core of radioactive isotope in a large accelerator can do. You just have to try it, if there at CERN read our articles."
The core is moving close to c and emitts γ-rays.The frame is the lab.
Supposed that math produce physics you know Zenon's parodox.

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elias2010	I am not talking about time dilation,what I am asking for is that if the moving core decays,b-rays emmited beyond the speed of light?

Ich Recognitions: Science Advisor	v > c for beta-rays? You mean, kind of v(beta relative to earth) = v(rocket) + v(beta relative to rocket) > c? Try this: http://en.wikipedia.org/wiki/Velocity-addition_formula

Whovian	Again, no, the formula isn't [itex]\vec{v}_{1,3}=\vec{v}_{1,2}+\vec{v}_{2,3}[/itex].

DaleSpam Mentor	Also, a Geiger counter does not measure speed of a radioactive particle, it only detects its presence. To measure speed you will need something else, like a Doppler radar.