科技資訊:世界上首次中微子通信服務

Neutrino communications

中微子通信

ET, phone home

外星人，致電家中

The world's first neutrino-messaging service

世界上首次中微子通信服務

PARTICLE physics is all very well for addressing trivial matters like "why are we here?" (see article). But some people question its practical usefulness. To answer such naysayers a group of physicists at Fermilab have just submitted a paper to Modern Physics Letters A in which they describe how they have built themselves a neutrino-powered telephone.

粒子物理學總是能很好地解決我們生活中遇到的像"爲什麼我們在這裏？"這類的瑣事。但是一些人會質疑它的實際可行性。爲了消除類似的質疑，費米實驗室的一羣物理學家剛向物理學界權威雜誌Modern Physics Letters A提交了一篇論文，論文中描述着他們怎樣爲自己成功定製了利用中微子載波的無線電通信電話。

Naturally, their neutrinophone is digital. A pulse of neutrinos (small, elusive subatomic particles with no electric charge) corresponds to the digit "1" while no pulse corresponds to "0". The neutrinos themselves are created by smashing bunches of protons into a target made of graphite. They are detected roughly 1km away by researchers who, in their day jobs, work on a neutrino collaboration called MINERvA. By modulating the pulses of protons the group was able to send a message in binary that, when translated, read "neutrino". Whether this will go down in history alongside Alexander Graham Bell's first message, "Mr Watson, come here, I want to see you," remains to be seen.

顯然，他們的中微子電話通信是數字化的。一箇中微子（一種不帶電荷形態詭異的亞原子粒子）脈衝對應着邏輯電平"1"，沒有脈衝時就對應着邏輯電平"0"。中微子產生於一些質子束轟擊一個石墨目標後產生脈衝介子，介子隨後衰變而成。整天工作於一個「主注入器之中微子V-A交互作用實驗（MINERvA）的研究員們在大概在一公里遠處能檢測到中微子。通過對質子束脈衝的調製編碼後，以二進制碼的形式進行中微子傳輸。是否這將延續亞歷山大?格拉漢姆?貝爾(Alexander Graham Bell)的歷史，以"Watson先生，請過來，我想見到你"進行首次中微子通信，我們拭目以待。

The point, though, apart from sheer wackiness, is that neutrinos are not easily intercepted by collisions with other sorts of matter. If humanity wanted to broadcast its existence to intelligent life forms that might be out in the galaxy listening, a modulated beam of neutrinos would be a good way of doing so. Conversely, some people argue that listening for ET at radio frequencies is the wrong approach. The right one, they think, would be to build a neutrino-receiver. And that would mean plenty of work for neutrino physicists. Perhaps, then, from its makers' point of view, the neutrinophone is not such a nutty idea, after all.

然而，重要的不僅是其古怪性而且中微子在傳輸中當受到其他物質的撞擊時不容易被破壞。如果人類想讓遠在銀河系的地方聽到充滿智慧生命存在性的廣播，那麼經過調製的中微子光束則是使他實現的一種很好的方式。相反，一些人認爲利用無線電廣播頻率收聽外星人是一種錯誤的方式。他們認爲正確的方式應該是搭建一箇中微子載波的接收器。這就意味着中微子的物理學家將需要做大量的工作。那麼，也許中微子電話的製造商會認爲，畢竟中微子電話並非是一個瘋狂的創意。