听力文本

If you've ever been to a rock gig,
假如你曾亲临摇滚现场
you'll probably recognize this screeching noise.
大概不会对这样刺耳的噪音感到陌生
It's feedback. What causes it is simple.
这便是"反馈"，其道理浅显
Sound enters the microphone.
声音进入麦克风

It's transmitted along the wires,
随后通过电缆传播
make louder by the amplifier.
经扩音器放大
and comes out at the speakers.
最终由音箱发出
But if too much of the sound from the speakers go back into the mike,
但倘若有太多声音由音箱返回麦克风
it goes round and round in a loop,
声音便会在此回路中不停折返
getting louder each time.
并被逐次放大
If no one stops it, feedback can destroy the sound system.
如不加阻止，反馈信号将毁坏音响系统
I think the same thing will happen with a wormhole,
我认为这也同样适用于虫洞
only with radiation instead of sound.
只不过传播的是辐射而非声音
As soon as the wormhole expands, natural
虫洞一旦开始张开
radiation will enter it and end up in a loop.
自然辐射便会进入其中并终结于回路
The feedback will become so strong, it destroys the wormhole.
反馈将足够强大以至将虫洞摧毁
So, although tiny wormhoes do exist,
因此尽管微型虫洞的确存在
and it may be possible to inflate one someday,
而且也可能某天被放大
it won't last long enough to be of use as a time machine.
其生命之短暂则无法被用作时间机器
That's the real reason no one came to the party.
这正是无人光顾派对的真正原因
In fact, I believe any kind of time travel to the past through
事实上，我基本不相信可以利用虫洞
wormholes or any other method is probably impossible.
或者其他可能手段重返过去
Otherwise, paradoxes would occur.
否则便会导致悖论
So, sadly,
因此遗憾地说
it looks like time travel to the past is never going to happen,
回到从前似乎永远不会发生
A disappointment for dinosaur hunters
这对于恐龙猎手恐怕是个遗憾
and a relief for historians.
但对于历史学界却是种解脱
But the story's not over yet.
不过故事尚未结束
This doesn't make all time travel impossible.
这并不意味所有时间旅行都无法实现
I do believe in time travel,
我对时间旅行深信不疑
time travel to the future.
相信人们能够跨入未来
Time flows like a river,
时间如河水般流淌
and it seems as if each of us is carried relentlessly along by time's current.
似乎人类也只能任由时间长河无情地摆布

视频及简介

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