如果告诉你，这些人脸都是机器生成的，现实生活中根本没有这些人，你信吗？这是一个叫ThisPersonDoesNotExist.com的网站，每次打开都会有一个新的人脸出现，这些都是AI自动生成的。

ThisPersonDoesNotExist.com uses AI to generate endless fake faces

The ability of AI to generate fake visuals is not yet mainstream knowledge, but a new website — ThisPersonDoesNotExist.com — offers a quick and persuasive education.

The site is the creation of Philip Wang, a software engineer at Uber, and uses research released last year by chip designer Nvidia to create an endless stream of fake portraits. The algorithm behind it is trained on a huge dataset of real images, then uses a type of neural network known as a generative adversarial network (or GAN) to fabricate new examples.

neural

表示“神经的；神经系统的”，英文解释为“Neural means relating to a nerve or to the nervous system.”如：neural pathways in the brain 大脑中的神经通路。

此处的neural network 神经网络，为人工智能领域的专业术语，包括后面出现的generative adversarial network, GAN 生成对抗网络也是当前人工智能领域，深度学习的先进技术之一。

生成对抗网络（GAN），维基百科给出的定义如下：

Generative adversarial networks (GANs) are a class of machine learning algorithms used in unsupervised learning, implemented by a system of two neural networks contesting with each other in a zero-sum game framework.

GAN到底是什么？这就涉及到LR的专业领域啦。

举个通俗的🌰，如造假币。GAN中有两个部分，一个叫生成器（generator），一个叫判别器（discriminator），造假团伙就是生成器，他们需要制造大量的假币，而银行就是判别器，银行需要判断钱币是真是假。造假团伙肯定希望自己的假币越真越好，而银行也需要想尽办法识别真假币的能力越强越好，因此二者之间就有一个对抗的过程，最终实现动态平衡：造的假币逼近于真币，银行区分不了真币和假币。

而这里利用GAN来生成人脸图像的道理也就类似生成钱币，最后生成出来的图像我们区分不出来这是真人还是虚构的人。这就是AI的厉害之处，后文也会提到，生成人脸图像只是其中的一种应用，按理说还可以生成各种各样的“东西”，当然图像是目前应用效果比较好的。

BTW，听说今年上外的基础英语出了一篇关于神经元的文章，难倒了大片考生...这也说明我们平时的眼界不能局限于某一个领域，应该尽可能多地涉猎自己专业之外的知识。

fabricate

1) 表示“编造，捏造”，英文解释为“to invent a story, piece of information etc in order to deceive someone”举个🌰：

The police were accused of fabricating evidence.

警方被控捏造证据。

2) 表示“制造，生产”，英文解释为“to make or produce goods or equipment technical”举个🌰：

The discs are expensive to fabricate.

这些磁盘的生产成本很高。

补充：

Register 语体

Fabricate is used mainly in writing, for example in journalism and legal contexts. In everyday English, people usually say make something up.

fabricate主要用于书面语，如新闻和法律文本。在日常英语中，人们一般说make something up，举个🌰：

They accused him of making the whole thing up.

他们指责他编造了整件事情。

“Each time you refresh the site, the network will generate a new facial image from scratch,” wrote Wang in a Facebook post. He added in a statement to Motherboard: “Most people do not understand how good AIs will be at synthesizing images in the future.”

from scratch

表示“从零开始”，英文解释为“If you do something from scratch, you do it without making use of anything that has been done before.”举个🌰：

Building a home from scratch can be both exciting and challenging. 

白手起家既激动人心又具有挑战性。

补充短语：

scratch one's head表示“绞尽脑汁思考”，英文解释为“If you say that someone is scratching their head, you mean that they are thinking hard and trying to solve a problem or puzzle.”举个🌰：

The Institute spends a lot of time scratching its head about how to boost American productivity. 

这家研究所花大量时间绞尽脑汁思考怎样推进美国的生产力。

synthesize

1) 表示“合成”，英文解释为“To synthesize a substance means to produce it by means of chemical or biological reactions.”举个🌰：

After extensive research, Albert Hoffman first succeeded in synthesizing the acid in 1938. 

经过大量研究之后，艾伯特·霍夫曼于1938年首次成功合成了迷幻剂

2) 表示“综合”，英文解释为“If you synthesize different ideas, facts, or experiences, you combine them to form a single idea or impression.”举个🌰：

The movement synthesized elements of modern art that hadn't been brought together before, such as Cubism and Surrealism. 

这次运动综合了立体派和超现实主义等以前未曾同时出现的现代艺术元素。

The underlying AI framework powering the site was originally invented by a researcher named Ian Goodfellow. Nvidia’s take on the algorithm, named StyleGAN, was made open source recently and has proven to be incredibly flexible. Although this version of the model is trained to generate human faces, it can, in theory, mimic any source. Researchers are already experimenting with other targets, including anime characters, fonts, and graffiti.

underlying

1) 表示“根本的；潜在的；隐含的”，英文解释为“important in a situation but not always easily noticed or stated clearly”举个🌰：

The underlying assumption is that the amount of money available is limited.

隐含的假定是，可用的资金有限。

2) 表示“表面下的；下层的”，英文解释为“existing under the surface of sth else”，如：the underlying rock formation 地表下的岩石结构。

mimic

表示“模仿（某人的言行，尤指为了逗乐），学…的样子”，英文解释为“to copy the way someone speaks or behaves, especially in order to make people laugh”举个🌰：

He could mimic all the teachers' accents.

他能模仿所有老师的口音。

As we’ve discussed before at The Verge, the power of algorithms like StyleGAN raise a lot of questions. On the one hand there are obvious creative applications for this technology. Programs like this could create endless virtual worlds, as well as help designers and illustrators. They're already leading to new types of artwork.

Then there are the downsides. As we've seen in discussions about deepfakes (which use GANs to paste people’s faces onto target videos, often in order to create non-consensual pornography), the ability to manipulate and generate realistic imagery at scale is going to have a huge effect on how modern societies think about evidence and trust. Such software could also be extremely useful for creating political propaganda and influence campaigns.

downside

表示“不利的一面”，英文解释为“The downside of a situation is the aspect of it which is less positive, pleasant, or useful than its other aspects.”举个🌰：

The downside of this approach is a lack of clear leadership. 

这种方式的不足之处是缺乏明确的指挥。

consensual

1) 表示“全体赞同的，一致同意的”，英文解释为“involving the agreement of all or most people in a group”，如：a consensual style of management 一致同意的管理风格。

2) 表示“双方同意的，两厢情愿的”，英文解释为“consensual sexual activity is wanted and agreed to by the people involved”。

imagery

1) 不可数，表示“形象化描述”，英文解释为“You can refer to the descriptions in something such as a poem or song, and the pictures they create in your mind, as its imagery.”如：the nature imagery of the ballad 民谣中的自然意象。

2) 不可数，表示“（尤指具象征意义的）图像”，英文解释为“You can refer to pictures and representations of things as imagery, especially when they act as symbols.”举个🌰：

This is an ambitious and intriguing film, full of striking imagery. 

这是一部气势恢宏、引人入胜的电影，充满了惹眼的镜头。

In other words, ThisPersonDoesNotExist.com is just the polite introduction to this new technology. The rude awakening comes later.

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