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Most physical objects in everyday life maintain the same identity whether we’re interacting with them, or not.
在日常生活中，无论我们是否与它们互动，大多数物理对象都保持着相同的身份。
Like, a baseball is a baseball whether you're holding it in your hand or it's flying through the air.
比如，棒球就是棒球，不管你是拿在手里还是在空中飞。
Even electrons are electrons whether they're part of an atom or flying freely through interstellar space; they have the same mass, same charge: they are electrons.
甚至电子也是电子，无论它们是原子的一部分还是在星际空间自由飞翔; 它们质量相同，电荷相同，它们是电子。
But neutrinos, those weird, super light, super fast, electrically neutral, hard-to-interact-with particles - they are identity-agnostic.
但是中微子，那些奇怪的，超轻的，超快的，电中性的，很难与粒子相互作用的，它们是身份不确定的。
Neutrinos have different identities depending on whether they’re interacting with other particles, or traveling freely, and on top of that their identities can change over time!
中微子有不同的身份取决于它们是否与其他粒子相互作用，或自由移动，最重要的是，它们的身份可以随着时间而改变!
Here’s what I mean: when they interact with other particles, like when they're produced in fusion in the sun or in radioactive decay,
我的意思是:当它们与其他粒子相互作用时，比如它们在太阳聚变或放射性衰变中产生时，
there are three different kinds of neutrinos, characterized by the particles involved in their creation or annihilation.
中微子有三种不同的类型，其特征是参与其产生或湮灭的粒子。
And when they're traveling through space, there are three different kinds of neutrinos, characterized by their masses.
当它们在太空中旅行时，有三种不同的中微子，以它们的质量为特征。
But these two sets of identities don't match up in a one-to-one correspondence; instead, each of the "interaction" identities is actually a mix of the three "traveling" identities.
但这两组恒等式并不是一一对应的; 相反，每一个“互动”身份实际上是三个“旅行”身份的混合。
And this weirdness allows neutrinos to change their identities.
这种奇异性使得中微子能够改变它们的身份。
That's because the traveling identities have different masses,
这是因为移动的恒等式质量不同，
so they travel differently from each other – technically what happens is they each pick up a complex-numbered phase depending on their mass and how far they’ve traveled,
所以它们彼此移动的方式是不同的，技术上来说，它们各自获得一个复数相，这取决于它们的质量和移动的距离，
but I’ll just show that using arrows that rotate at different speeds, which is essentially the same thing.
但我将用不同速度旋转的箭头来演示，这本质上是一样的。
Anyway, because the arrows rotate at different speeds, over time a combination that initially looked like an electron-interacting neutrino might become the muon-interacting combination.
无论如何，因为箭头以不同的速度旋转，随着时间的推移，最初看起来像电子相互作用的中微子的组合可能会变成μ介子相互作用的组合。
And then, if you wait longer, the combination will look like an electron-interacting neutrino again, then muon-interacting, and so on, back and forth.
然后，如果你再等一段时间，这个组合又会看起来像一个电子相互作用的中微子，然后是介子相互作用，如此往复。
all happening as the neutrino flies super fast through space.
这一切都发生在中微子在太空中以超快速度飞行的时候。
It’s kind of like if I took my violin and played an A , and somehow by the time the sound waves reached your ear,
这就像如果我拿起我的小提琴，拉了一个A，不知怎么的，当声波到达你的耳朵时，
the relative strengths of the frequencies had shifted so you heard the sound as an E, or a D, or an A, depending on how far away you were.
频率的相对强度发生了变化，所以你听到的声音是E、D或A，这取决于你离得有多远。
In fact, the oscillation of neutrinos back and forth between different identities was discovered in part because we didn’t see as many neutrinos coming from the sun as our understanding of fusion suggested.
事实上，发现中微子在不同身份之间来回振荡，部分原因是因为我们看到的来自太阳的中微子并不像我们对聚变的理解所暗示的那么多。
It turned out that about 2/3 of the electron-interacting neutrinos had turned into muon and tau-interacting neutrinos en route to the earth, in a very real, very long-range example of quantum superposition!
结果是，大约2/3的电子相互作用的中微子在通往地球的路上变成了介子和介子相互作用的中微子，这是一个非常真实的、非常远距离的量子叠加例子!
Oh, and one other little technicality: even though the three “interaction”-neutrinos are named after the specific electron-family particles that are involved in their creation and annihilation,
哦，还有一个小的技术性问题:即使这三种“相互作用”——中微子是以它们的产生和湮灭所涉及的特定电子族粒子命名的，
they can still interact with (that’s physics-speak for “bounce off of”) other members of the electron family as well as quarks.
它们仍然可以与电子家族的其他成员以及夸克相互作用(这是物理学的说法，指的是“反弹”)。
Ok, I’d like to thank the Heising Simons foundation for their support of this video and of neutrino research!
好的，我要感谢海辛·西蒙斯基金会对这个视频和中微子研究的支持!
They put me in touch with some of the neutrino researchers they help fund, who were awesome to talk to and learn from.
他们让我和他们资助的一些中微子研究人员取得了联系，与这些研究人员交流和学习是非常棒的。
And Heising Simons also funds a variety of research in other fields, like exoplanets, microscale gravity, climate change, and so on.
海辛·西蒙斯还资助了其他领域的各种研究，比如系外行星、微尺度重力、气候变化等等。
To learn more about Heising Simons, check out heisingsimons.org.
想了解更多关于海辛·西蒙斯的信息，请访问heisingsimons.org。
