浙江龙网

  1. 首页 > 生活百科 > >

密码学中mod是什么意思 密码学中的state是什么意思( 三 )

生活百科


然后这些光子会被执行由Gilles (Gilles Brassard) 和我发展出的特定的操作
即我们把四种不同偏振的光子从Alice发送到Bob
然后我们对普通信息进行一个经典的讨论
这些信息是窃听者可以窃听的
最终的结果是，Alice和Bob之间有一串共享密钥串
如果有太多窃听，他们会把这串密钥丢弃
如果能以很高的置信度知道并没有窃听行为
他们会知道这个密钥只属于他们，其他任何人都不知晓

密码学中mod是什么意思 密码学中的state是什么意思

文章插图

现在我开始讲另一种密码术，这种密码术建立在量子纠缠上
但是我需要解释什么是纠缠
但是这种不确定原理是无法摆脱的
如果你试着测量光子，你无法准确测量它的偏振
如果你不知道最开始的偏振是什么
因此不存在这样一种装置，你放进去一个光子
它会告诉你这个光子的偏振是什么
你无法克隆一个光子，因为如果你可以克隆它
你就可以造出成千上万的光子
然后测量光子，从统计数据中以任意精度确定光子的偏振
存在一种可以放大光子的装置
我手中就拿着一个，这个装置叫激光
但是激光的工作原理是
你知道“laser”这个单词意思是受激辐射光放大
这个意思是，你输入一个光子，会由几个光子输出
它们通常工作在振荡模式下
所以它可能是一个关于受激辐射的光振荡器
但是他们认为“loser”这个缩写并不是很好
因此无论如何，这是一个光放大器
但是有一个关于激光的事
光放大器的意思是如果你输入一个非常弱的信号
例如一个单光子
有时它会被放大，但有时不会被放大
所以你会得到一个与它一起输出的噪声光子
所以，光束会变得更亮
但是在分辨光子偏振上，与原始未放大光子相比
亮光束不会更有用
因此没有办法解决这个不确定原则
——The end——
了解更多量子密码学
旧时代密码术和密码学圣杯 （上）冷战中的“一次一密”| Gilles Brassard
公钥密码术的原理、发展及其在量子时代的困境 （中） | Gilles Brassard
量子密码学的诞生及其战场（下）| Gilles Brassard
量子密码学的实现（上）爱因斯坦的困惑| Artur Ekert
量子密码学的实现（下）像物理学家一样思考| Artur Ekert
英文版
So I'm going to be talking about the relation of physics to mathematics also.
But what I'd like to do is take an area of mathematics or physics,
which is considered to be really hard to understand, worse than rocket science.
And give you some tools for understanding it
if you're not a technically minded person.
Or if you are a technically minded person,
some metaphors are ways of explaining it to the general public.
Because I think the non understanding of quantum physics,
which is now lies at the root of information and communication,
is a terrible thing to not understand.
It's one of the fundamental things about the universe that we live in
that everyone should understand, not just scientists.
And that means that we need to find the right ways of explaining it.
We're in the middle of an information revolution.
This revolution is based on some really brilliant abstractions by many people.
But we associate them with Turing,
who put the theory of computing into an abstract basis,that is
that you can think about computing is independent of the notion of thehardware.
There is a universal notion of computing.
There is a universal computer that can simulate any other computer.
And Shannon,
who did something even more revolutionary,
that is to think about communication in an entirely mathematical way.
That is that there is a theory of communication.
that is independent of the meaning of the message.
Now,even today, if you try to say to a person on the street,
"I want to tell you about communication without telling you about meaning."
they would think you were a little crazy.
And yet that's what leads to the information revolution we had today.
But the information carriers, Turing and Shannon thought about, were viewed
as what a physicist would call a classical system.
And that is that their statesare in principle reliably distinguishable,
and are not disturbed by measuring them.
Youcan make a copy of information.
In fact, you can do it very easily.
And the only kind of trouble you can get into is a typically legal trouble.
Tospecify the joint state of two things,
it's necessary and sufficient to say the state of each one.

推荐阅读


上一篇：除以符号怎么写，除以和除的区别在哪儿

下一篇：孕妇梦见自己生孩子了是什么意思