It is fairly safe to say that everyone has at least heard of radioactivity.
But what exactly IS it?
Well, it is a bit like the commercial for Red Rock Strong Lager - "It is not red, and there are no rocks in it"
"radioactivity" is similar - "It has nothing to do with radios, and it is not about activity, but the lack of it"
Scientists discovered it because it kept making them very ill.
When we studied it, we found there were three basic types. We called them after the first three letters of the Greek alphabet, Alpha, Beta and Gamma (our word "alphabet" came from the joining of the first two)
They were classed according to how dangerous they were.
Alpha - stopped by paper
.
Beta - stopped not by paper but tin foil.
Gamma - stopped only by several centimeters of lead (about 10)
But what were they?
By doing various esoteric experiments it turned out they were:
Alpha - Helium nuclei (to protons, two neutrons)
Beta - electrons (or their antiparticles, positrons)
Gamma - very high energy light rays (electromagnetic radiation)
The danger?
Alpha - forget it
Beta - Don't go swimming in a pool that glows blue (yes, GLOWS) If you do, it will be an atomic reactor and the glow is because the electrons are traveling faster than the speed of light in water.
Gamma - Be at least 12 miles from an atomic bomb
The danger is the damage gamma rays do. It is at the cellular level, which means that gamma rays are so powerful they pass right through you, except if they hit the nucleus of a cell (nothing to do with an atomic nucleus).
The danger of that is that if a cell is damaged, there is a very high probability of contracting cancer.
The fact that many people do not realise is that the effects of radiation poisoning are cumulative, rather like the way an hourglass works. Over time, the sand builds up in the bottom half.
Radiation is the same. There will come a point when the poisoning has "built up" so much that exposure to more will be really dangerous.
We wear badges that tell us how much "sand" has passed though us. In that sense, our work is very dangerous.
In the opposite sense, our work is very safe, simply because it is controlled.
Having said that, the door to the experimental area is a 2-meter by 1-meter by 1-meter tank of water.
Thursday, April 09, 2009
".....Nor any Drop to Drink"
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7 comments:
Could you please explain if Beta rays are electrons, how it is they can travel faster than light-speed in water? Seems I have heard this somewhere before.
Another request, but speculative, I suppose. If the above is true and not a joke, then might there be a means of exploiting this to travel faster than light-speed? Say, a spaceship with a Beta-coating--so to speak--so it reacts like an electron, with the spaceship embedded in water. A longshot prospect, but thought I would ask. Thank you.
Nothing can travel faster than the speed of light in free space, but stuff like water, the spoeed of light is less (it's one of the definitions of refractive index).
There is nothing in relativity forbidding other stuff in water travelling faster than the speed of light IN water.
I repeat, nothing can travel faster than light in vacuo
Thank you for both explanations. Forgot that refractive index thing. I don't think I run into refractive index a lot, although I am seeing it pop up more in scientific literature. Particularly in connection to Stealth research. Oops! That is a negative refractive index, though, isn't it? Sorry, get all these things mixed up sometimes.
You cannot have negative refractive index.
Stealth fighters are stealth because they reflect little radar because of their shape.
Radar "sees" a stealth fighter and it's radar reflection is the same a a pigeon, it is that small.
No disrespect, for no one can keep up with everything, but you need to look up current research on negative refractive index, for they have made advances in this area you are not aware of. Yes, I know, the science I read is not technical literature and I have "NO" books on this subject. Just wish someone in the field would comment rather than me. I have read online stories about such research.
I have read online "stories" about people who have built real time machines.
I do not believe what people write online.
I have just googled both "negative refractive index" and "metamaterials".
What I saw were the words "could", "would" and the phrase "it may be possible".
Forgive my cynicism, but I counter these claims by citing the other definition of refractive index.
"refractive index" = "the speed of light in vacuo divided by the speed of light in the medium".
Since both are always positive (they are speeds), how can the ratio possibly be negative?
The two HAVE to agree.
I really think they have not thought this through, and that the people who claim that have made things "disappear" need to allow other scientists to reproduce their results.
The phrase "cold fusion" comes to mind.
The articles on Wikipedia, which seem official, were probably written by the same "scientists" who made the claims.
It is different in my field, in that many scientists use the same equipment and produce the same results.
To wit, it is too soon to either disprove or prove these people's claims.
Because that is all these people do, "claim".
Our field don't "claim", we do, we publish on how to do it, and others read and prove that what we do is true.
I see no evidence of this negative refractive index in the scientific journals for these so-called "claims".
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