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Can radioactivity be slowed using the effect of time dilation?

If you put cesium, tritium or uranium in a cyclotron at relativisitic speeds, do their half lives become longer in our frame?

Could this be used as a means to store radioactive material?

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If you can find a way to spend less money accelerating a radioactive material to 0.99c than the value of the amount of material you'd have lost then go ahead. Look up the running costs of the LHC, capable of getting a few bosons to 0.99c, this is huge orders of magnitude away from what would be useful not to mention it's a mechanism that only works on charged particles. – Duke of Sam Feb 24 at 16:03
In reality, the biggest problem with storing radioactive waste is the sheer length of time it remains radioactive. Plans have to be made for hundreds if not thousands of years not to disturb the waste. So time dilation would actually be counterproductive – Binary Funt Feb 24 at 17:08
If you have enough energy to get a ton of radioactive material going that fast then you have more than enough energy to simply drop it into the sun; storage problem solved. – Eric Lippert Feb 24 at 17:13
If it didn't, you could find out your "absolute speed," couldn't you? – wchargin Feb 25 at 0:55
@EricLippert: Oh noes! Now the sun is radioactive. Humanity is doooomed! :-( – Henning Makholm Feb 25 at 9:11

Yes. The classic example is that this is the only reason muons produced by cosmic radiation high up in the atmosphere live long enough to reach the ground.

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Literally the answer I was going to give. It's worth pointing out that there is nothing special about radiation. All events separated by a given amount of time are susceptible to time dilation. – Duke of Sam Feb 24 at 16:00
Good answer, that could be made better with a couple of references. – Floris Feb 24 at 17:32
@DukeofSam Although the available answers address the OP's question I feel that the point you mentioned "All events separated by a given amount of time are susceptible to time dilation." should be elaborated as a separate answer. Because, the reason OP asked this question is the lack of the realization that it is not about the nature of the process, it is about the general property of the temporal interval between the end-points of the process. – Dvij Feb 24 at 17:56
Muon decay is the key to remembering so many concepts of special relativity. For instance, the alternative interpretation - that the distance from the top of the atmosphere to the ground is shorter - is how I remember when Lorentz contraction occurs. – dotancohen Feb 25 at 17:23

Could this be used as a means to store radioactive material?

The volume or mass of material which could be stored this way would be extremely small. OTOH, there are radioactive ion beams used in experiments which might benefit from relativistic speeds in the beam line.

A literature search on relativistic radioactive ion beams reveals several experiments like this at relativistic energies, but the time dilation effects don't appear to be the primary motivation behind them, but rather the large energies which give better statistics for low cross-section reactions. See this paper.

They are also used specifically to have high-precision tests of special relativity: See this article.

But storage of large quantities of short-lived nuclides doesn't seem realistic. The energy demands to keep them moving would be overwhelming and not cost effective. It's better to make them as you need them.

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The answer is yes but the amount of energy needed to generate a measurable time dilatation effect would be prohibitive. Let us say you put the material in the fastest centrifuge available today. The time dilatation would be on the order of a billionth of a second or less.

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A billionth of a second from the radioactive material's point of view, or from an external observer's point of view? – jwg Apr 29 at 13:19

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