Will we ever be able to teleport? - Sajan Saini

譯者: Szu-Wen Kung 審譯者: Helen Chang

Is teleportation possible?

瞬間移動可能嗎？

Could a baseball transform into something like a radio wave,

棒球有可能轉換成像無線電波

travel through buildings,

穿越建築物

bounce around corners,

彈繞過角落

and change back into a baseball?

然後再度變回棒球？

Oddly enough, thanks to quantum mechanics, the answer might actually be yes.

奇怪的是，多虧量子力學 答案竟有可能是肯定的

Sort of.

或多或少

Here's the trick.

秘竅是

The baseball itself couldn't be sent by radio,

棒球本身不能由無線電波傳送

but all the information about it could.

而所有與棒球相關的資訊能

In quantum physics, atoms and electrons

在量子物理學，原子和電子

are interpreted as a collection of distinct properties,

被解讀為具備獨特屬性的集合體

for example, position,

例如，位置

momentum,

and intrinsic spin.

動量

及本質自旋

The values of these properties configure the particle,

這些屬性的值配置粒子

giving it a quantum state identity.

賦予它量子狀態的標識

If two electrons have the same quantum state,

若兩個電子有一樣的量子態

they're identical.

這兩個電子就相同

In a literal sense, our baseball is defined by a collective quantum state

字面上，棒球可用其眾多原子的

resulting from its many atoms.

量子態集合來解釋

If this quantum state information could be read in Boston

若能在波士頓讀取量子態的資訊

and sent around the world,

傳送至世界各地

atoms for the same chemical elements could have this information

相同化學元素的原子

可以在印度的班加羅爾印上這些資訊

imprinted on them in Bangalore

and be carefully directed to assemble,

透過縝密的原子組合

成為與原來一樣的棒球

becoming the exact same baseball.

There's a wrinkle though.

不過仍舊有困難

Quantum states aren't so easy to measure.

量子態並不易測量

The uncertainty principle in quantum physics

量子物理學的「不確定性原理」

implies the position and momentum of a particle

意味著無法同時測量

can't be measured at the same time.

粒子的位置與動量

The simplest way to measure the exact position of an electron

測量電子準確位置的最簡單方式

requires scattering a particle of light, a photon, from it,

需要將原子光束，即光子 從電子中散射出來

and collecting the light in a microscope.

然後將光束收集到顯微鏡中

But that scattering changes the momentum of the electron in an unpredictable way.

然而散射卻無法預測地 改變電子的動量

也會失去之前一切有關動量的資訊

We lose all previous information about momentum.

In a sense, quantum information is fragile.

也就是說，量子的資訊很脆弱

Measuring the information changes it.

測量這些資訊會將之改變

So how can we transmit something

所以我們該如何傳遞那些

we're not permitted to fully read without destroying it?

不破壞就無法完全解讀的物質呢？

The answer can be found in the strange phenomena of quantum entanglement.

奇妙的「量子纏結」現象能提供解答

Entanglement is an old mystery from the early days of quantum physics

量子纏結老早便是 量子物理學的一個謎團

and it's still not entirely understood.

就算至今，仍無法讓人完全理解

Entangling the spin of two electrons results in an influence

兩個纏結的自旋電子

會產生超越距離的影響

that transcends distance.

Measuring the spin of the first electron

測量第一個電子的自旋

determines what spin will measure for the second,

能決定第二個電子的自旋測量

whether the two particles are a mile or a light year apart.

無論兩個粒子相隔多遠

Somehow, information about the first electron's quantum state,

有關第一個電子的量子態資訊

called a qubit of data,

又名「量子位元資料」

influences its partner without transmission across the intervening space.

不用穿越空間距離就影響其同伴

Einstein and his colleagues called this strange communcation

愛因斯坦與其同事 稱此奇怪的溝通為

spooky action at a distance.

「遠距離的鬼魅作用」

While it does seem that entanglement between two particles

事實的確顯示兩個粒子之間的纏結

helps transfer a qubit instantaneously across the space between them,

能幫忙即刻傳遞彼此之間的量子位元

there's a catch.

但有個前提

This interaction must begin locally.

此互動必須始於近距離

The two electrons must be entangled in close proximity

兩個電子必須在相鄰狀況下纏結

before one of them is transported to a new site.

然後才能將其中一個運送至新地點

By itself, quantum entanglement isn't teleportation.

量子纏結本身並非瞬間移動

To complete the teleport,

想要完成瞬間移動

we need a digital message to help interpret the qubit at the receiving end.

我們需要一組數位資訊 協助解讀接收端的量子位元

Two bits of data created by measuring the first particle.

也就是測量第一個粒子 所產生的兩個數字位元資訊

These digital bits must be transmitted by a classical channel

這些數字位元必須經由 受光速限制的傳統途徑傳送

that's limited by the speed of light, radio, microwaves, or perhaps fiberoptics.

無線電、微波或光纖

When we measure a particle for this digital message,

當我們測量這些數字位元的粒子

we destroy its quantum information,

就損壞其量子資訊

which means the baseball must disappear from Boston

意思是棒球必須從波士頓消失

for it to teleport to Bangalore.

好使其瞬間移動到班加羅爾

Thanks to the uncertainty principle,

這是基於不確定原理

teleportation transfers the information about the baseball

瞬間移動在兩個城市間

between the two cities and never duplicates it.

傳遞而不是複製這些有關棒球的資訊

So in principle, we could teleport objects, even people,

所以基本上我們能 瞬間移動物體甚至人

but at present, it seems unlikely we can measure the quantum states

但是現今我們似乎還無法測量

大型物體中數萬億個原子的量子態

of the trillion trillion or more atoms in large objects

and then recreate them elsewhere.

並在另一處將之重新創造

The complexity of this task and the energy needed is astronomical.

此任務極為複雜 所需的能量也非常龐大

目前我們確實能夠 瞬間移動單個電子和原子

For now, we can reliably teleport single electrons and atoms,

which may lead to super-secured data encryption

這可能為未來的量子電腦

for future quantum computers.

帶來絕對安全的資料加密

The philosophical implications of quantum teleportation are subtle.

量子瞬間移動的哲學寓意也頗微妙

A teleported object doesn't exactly transport across space

瞬間移動物體

並不完全像有形物質穿過空間那樣

like tangible matter,

nor does it exactly transmit across space, like intangible information.

也不完全像在空間中傳遞無形的資訊

It seems to do a little of both.

其實是兼具兩者的些許特性

Quantum physics gives us a strange new vision

量子物理學帶給大家奇妙的新觀點

for all the matter in our universe as collections of fragile information.

即視宇宙萬物為脆弱資訊的集合體

And quantum teleportation reveals new ways to influence this fragility.

而量子瞬間移動揭示了 影響這種脆弱性的新方式

And remember, never say never.

別忘了沒有絕不可能的事

In a little over a century,

還不到一百多年

mankind has advanced from an uncertain new understanding

人類對原子規模的電子運動

of the behavior of electrons at the atomic scale

從原本不確定的新認知

to reliably teleporting them across a room.

進步到確實能將電子 瞬間移動到房間的另一頭

What new technical mastery of such phenomena

類似如此現象的技術突破

might we have in 1,000, or even 10,000 years?

在一千年甚至一萬年內 又會有甚麼新的發展

Only time and space will tell.

只賴時間和空間來揭示了