Stephen Hawking gave a speech via hologram. Again.

Cosmologist Stephen Hawking spoke in Hong Kong on Friday — only he wasn't actually present for the speech. 

The world-renowned physicist actually gave his speech live via hologram for the 90-minute lecture about his life and work. He was beamed in for his lecture from the UK. 

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"Hawking spoke about the human mind, societal trends and issues such as education and science and technology research and funding, as well as what the future holds in light of current affairs," according to a press release about the event.

If you can believe it, this isn't the first time the famous scientist has given a speech via hologram. 

Hawking in front of a greenscreen.
Hawking in front of a greenscreen.

Image: ARHT MEDIA/PAUL DUFFY

A hologram of Hawking was also used for a speech before a crowd at the Sydney Opera House in 2015. 

The hologram-creating technology — developed by ARHT Media — makes use of a greenscreen and internet connection. You don't need 3D glasses to see the hologram, making the experience that much more immersive. 

Hawking was diagnosed with ALS when he was 21 years old. He is now wheelchair bound and uses a voice assistant. He is known in the scientific community for his breakthroughs in black hole science. 

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