Virtual Reality Gets Real 當虛擬成為現實

李友之

七歲的小女孩愛麗絲在夢里跌入了兔子洞見到了稀奇古怪的人物和光怪陸離的場景。虛擬現實就是要創造出這樣的夢，用計算機及傳感器技術，以假亂真，讓人身臨其境。VR眼鏡的流行，宣告著這項技術的進一步發展。然而，這場人類企圖戰勝時空的夢，究竟是美夢還是噩夢呢？

In 1965， Ivan Sutherland， a computer-graphics pioneer， addressed an international meeting of techies on the subject of virtual reality. The ultimate virtual-reality display， he told the audience， would be “a room within which the computer can control the existence of matter. A chair displayed in such a room would be good enough to sit in. Handcuffs displayed in such a room would be confining， and a bullet displayed in such a room would be fatal. With appropriate programming， such a display could literally be the Wonderland into which Alice walked.”

Virtual reality has advanced rapidly in the past couple of years—the much-anticipated Oculus Rift headset arrived in stores in early 2016， followed closely by several other devices. Yet the technology is still very new， and Sutherlands vision seems little closer to， well， actual reality. “Right now， its like when you first had cellphones，” Richard Marks， one of the lead engineers working on Project Morpheus1， Sonys virtual-reality headset， told me. “A lot of focus is still on the most basic things.”

I recently spoke with scientists， psychologists， engineers， and developers about the possibilities for this emerging field. Where might it eventually take us—and will that be somewhere we want to go？

Being Virtually Anywhere

During a recent demonstration of Google Cardboard—a DIY headset thats made of cardboard and uses a smartphone for the display—I found myself by turns atop a rocky peak， in a barn next to a snorting horse， and on a gondola making my way up a mountain.2 The gondola ride gave me vertigo3.

We react like that， experts say， because our brains are easily fooled when what we see on a display tracks our head movements. “We have a reptilian4 instinct that responds as if its real： Dont step off that cliff； this battle is scary，” Jeremy Bailenson， the founding director of Stanfords Virtual Human Interaction Lab， told me. “The brain hasnt evolved to tell you its not real.”

Much of the excitement about virtual reality has come from the gaming community. Who wouldnt want to experience a game so completely？ But gaming is just the start. At Sony， Marks has worked with NASA to conjure5 the experience of standing on Mars—a view that could help scientists better understand the planet. David Laidlaw， the head of the Visualization Research Lab at Brown University， told me that his team has re-created a temple site in Petra， Jordan， enabling researchers to see previously unclear relationships between objects found there.

Google is testing Expeditions， a way of sending students to places like the Great Barrier Reef， where they can virtually scuba dive as part of a lesson on marine biology and ocean acidification.6 Similar approaches may enhance professional training. By donning a pair of goggles， a neurosurgeon could navigate brain structures before surgery； a chemist could step inside a drug to understand it on the cellular level；7 an architect could walk through a building shes designing.

Another possibility： Imagine that youre unable to attend a family gathering. With a pair of glasses， youre in the middle of the action. And everyone there wears glasses that make it appear as though youre present. The whole thing is recorded， so you can replay the experience whenever youd like. Ten years from now， such a scenario8 might be common.

And consider the potential for telecommuting9. Henry Fuchs， a professor at the University of North Carolina at Chapel Hill and a leader in the field， envisions virtual offices. You could use the physical space of your house—a real desk， a real computer—but interact with your colleagues as if they were in the same room as you.

Engaging All Your Senses

Google recently acquired Thrive Audio， a company that specializes in spatial audio—sounds that your ear registers as emanating from a particular place.10 A virtual waterfall grows louder as you move toward it. Something catches your ear from behind. You turn， and see a deer approaching. The audio becomes three-dimensional， truly surrounding you.

Smell could become part of the virtual experience as well. A company called Feelreal has developed a mask that releases scents， such as the smell of fire or the ocean， to enhance what you see in a headset. （The project is hampered by the need to preload the scents youre likely to encounter， among other problems.） Closely related is the ability to taste what you see. Researchers in Singapore are developing electrodes that， when placed on your tongue， mimic basic tastes，11 such as sweet， salty， bitter， and sour.

What about touch？ Could we one day find that when we dip our fingers in virtual water， it actually feels wet？ David Laidlaw considers resolving this challenge， known as the haptics problem， to be the holy grail of virtual reality.12 But that doesnt mean its insurmountable13. “Im confident well do it within our lifetimes，” Palmer Luckey， the founder of Oculus， told me. “There are no fundamental physical laws that prevent us from building something thats almost perfect.” Laidlaw is less optimistic—he thinks that creating lifelike haptics will take 100 years—but he agrees that a virtual world may one day be a nearly perfect simulacrum14 of the real one.

Of course， there could be unintended consequences. Already people are developing vision problems and vitamin D deficiencies—not to mention obesity and diabetes15—because they spend too much time in front of screens. What might a flawlessly rendered virtual world mean for our health？

A Neuromancer Future？

Jeremy Bailenson was inspired to work in virtual reality in part by Neuromancer， a 1984 novel that depicts a future in which people can “jack in” their brains directly to a virtual world. Perhaps， Bailenson speculates16， thats where virtual reality is headed. He imagines that in 50 or 100 years we might develop a brain-machine interface17 that taps directly into the nervous system.

Perhaps then well find that rather than jacking in for a while and calling it quits， we can， like Alice， move wholly into a Wonderland where the laws of the prosaic18 world （gravity， aging） no longer apply. Virtual reality could then become akin to the Singularity， a concept described by Ray Kurzweil，19 a futurist and Google engineer， among others： a way for our minds to separate from our bodies and， uploaded into a digital realm， live on even as our physical selves grow old and die. Just like Wonderland， its a vision equal parts entrancing and frightening.

1965年，計算機圖形學先驅伊凡·蘇澤蘭在一個全球性的科技會議上發表了一場關于虛擬現實的演講。他告訴聽眾，“最終的虛擬現實，將會呈現出一個這樣的房間，里面所有的物品都由電腦控制。房里的凳子真的可以坐，手銬真的可以銬住人，子彈也真的會置人于死地。只要合理設定程序，這樣的房間完全可以變成愛麗絲踏入的那個奇境。”

過去的幾年里，虛擬現實技術發展迅速。備受期待的Oculus Rift頭戴式顯示器2016年初就已經面世，其他設備也相繼推出。但這項技術還是太新，蘇澤蘭的設想也太遙遠。“現在這個階段，就跟我們剛有手機那會兒一樣，注意力還是集中在一些基礎的問題上。”索尼公司代號為“摩爾甫斯”的虛擬現實頭顯設備項目的工程師理查德·馬克斯告訴我說。

這個逐漸壯大的領域能走多遠，我最近跟科學家、心理學家、工程師、開發人員都談到過。它最終會把我們帶向哪里，是我們想要到達的終點嗎？

虛擬無處不在

在最近一次的“谷歌紙盒”（一個由紙盒做成的手工頭顯設備，可用智能手機操控）展覽上，我接連體驗到了身處險峻的山巔、站在牲口棚里呼呼噴氣的馬匹旁邊，以及坐在纜車中盤山而上之感。乘坐纜車著實令我頭暈目眩。

專家說，我們之所以會有這樣的感覺，是因為當我們看到的東西跟隨頭部的運動而變化時，大腦很容易上當。“我們有著像爬行動物一樣的直覺，會誤以為是真實情況并作出反應：那個懸崖別踩空了；這場戰役很殘酷。”斯坦福虛擬人機交互實驗室的創辦主任杰里米·拜倫森告訴我說，“大腦還沒有進化到可以告訴你那不是真的。”

對虛擬世界的熱衷大多來自源于游戲社區。誰不想全方位地體驗游戲場景呢？但游戲只是一個開始。在索尼公司，馬克斯和美國國家航空航天局一道，創造出了站在火星上的視覺感受，以幫助科學家更好地理解火星。布朗大學可視化研究實驗室的負責人戴維·萊德勞告訴我，他的團隊重現了約旦古城佩特拉的廟宇遺址，幫助研究者弄清此前在遺址里發現的各個文物之間的聯系。

正在測試的谷歌探險項目，可以把學生送到大堡礁等地，讓他們進行虛擬水肺潛水，以此作為海洋生物學和海洋酸化課程的一部分。同樣的方法也可以用來強化專業培訓。戴上護目鏡，神經外科醫生可以在手術前就探測好大腦的結構；藥劑師則可以進入到藥物內部，從細胞層面去了解它的效用；設計師可以走進她正在設計的建筑。

還有一種情況，比如有一次家庭聚會你沒法參加。戴上一副眼鏡，你就可以置身其中了。現場的每個人也都戴著眼鏡，也會感覺你在現場。全程都有錄像，這樣你隨時都可以重溫這個場景。10年后，這種情況可能會很普遍。

虛擬現實還有可能應用在家庭辦公方面。亨利·福克斯是北卡羅來納大學教堂山分校的教授，也是相關領域的領頭人，他提出了虛擬辦公室的設想。你可以用家里的真實場景——真實的書桌，真實的電腦——跟同事互動，就像他們和你在同一間屋子里一樣。

調動所有感官

谷歌最近收購了Thrive Audio，這家公司專注于空間音頻——能讓耳朵分辨出來自特定方位的聲音。你靠得越近，虛擬瀑布的聲音越響。你聽到身后的響動，轉過身，發現是一只鹿正在走近。聲音變成了三維的，實實在在環繞著你。

氣味也可以成為虛擬體驗的一種。一家名叫Feelreal的公司研發出了一種可以釋放氣味的面具，通過釋放出燃燒物或者海洋這類的氣味，強化你在頭顯中看到的場景。（這個項目還有一些問題沒有解決，比如必須事先就存入可能需要的氣味。）與此密切相關的還有，在你看到一個東西的同時，也能夠嘗到它的味道。新加坡的研究人員正在開發一種電極，它可以在被放到舌頭上時，模擬出甜、咸、苦、酸等一些基礎味道。

那么觸覺呢？會不會有一天，我們把手伸到虛擬的水中時，會真的感覺到水的濕潤？戴維·萊德勞把觸覺技術看作虛擬現實領域一個難以逾越的高峰，但也不是完全不能攻克。Oculus的創始人帕爾默·勒基對我說：“我相信我們會在有生之年攻克這個難關。創造出近乎完美的技術，并不會違反基本的物理定律。”萊德勞則沒有那么樂觀，他認為創造栩栩如生的觸覺體驗需要一百年時間，但他也認同總有一天虛擬世界會模擬出一個近乎完美的真實世界。

當然，結果可能會出人意料甚至適得其反。因為在電子屏幕前待得太長，人們已經開始出現視力障礙和維生素D缺乏癥，更別提肥胖和糖尿病了。一個完美的虛擬世界對我們的健康又意味著什么呢？

《神經漫游者》式的未來？

杰里米·拜倫森致力于虛擬現實領域，部分是因為受到了《神經漫游者》的啟發。在這部1984年出版的小說里，未來的人們可以直接將大腦“接入”到虛擬世界。或許，拜倫森推測，這就是虛擬現實發展的方向。他預測在50至100年后，我們可能會研制出一種人機接口，可以直接將機器連入大腦神經系統。

恐怕到那時，我們甚至都不用接入一會兒，再退出來，而是像愛麗絲一樣，完完全全地進入一個奇境，不再受重力、衰老等各種規則的束縛。那時虛擬世界會類似于“奇點”，這是未來學家、谷歌工程師雷·庫茲韋爾描述的概念：我們的靈魂從軀體中脫離出去，進入到數碼國度，即便軀體衰老死亡，靈魂都能永生。跟愛麗絲的奇境一樣，這樣的未來既讓人向往，也有些可怖。

1. Morpheus： 摩爾甫斯，希臘神話中的夢神。

2. barn： 牲口棚，谷倉；gondola：（索道）纜車。

3. vertigo： 眩暈。

4. reptilian： 爬行動物的，爬行動物似的。名詞形式為reptile，爬行動物。

5. conjure： 用魔法變出，使某事發生。

6. scuba dive： 水肺潛水，scuba是self-contained underwater breathing apparatus的縮寫，指潛水員自行攜帶水下呼吸系統所進行的潛水活動；acidification： 酸化。海洋酸化（ocean acidification）是指海洋攝入大氣中的二氧化碳后，海水堿度減弱，酸度上升的趨勢。海洋酸化會破壞海洋生態系統的功能，對海洋物種產生影響。

7. don： 戴上；goggles： [復]護目鏡； neurosurgeon： 神經外科醫生；cellular： 細胞的，由細胞組成的。

8. scenario： 可能發生的事，可能出現的情況。

9. telecommute： 家庭辦公，遠距離工作。

10. register： 注意到；emanate： 散發出，傳出。

11. electrode： 電極；mimic： 模擬。

12. haptics： 觸覺學；holy grail： 原指耶穌死前用過的圣杯。傳說如果能找到圣杯，喝下其盛過的水，就能返老還童、死而復生。此處用來比喻夢寐以求的目標，盡力實現的夢想。

13. insurmountable： 不可逾越的，難以克服的。

14. simulacrum： 擬像，模擬物。

15. deficiency： 缺乏，不足；diabetes： 糖尿病。

16. speculate： 推測，猜測。

17. interface： 接口。

18. prosaic： 乏味的，缺乏想象力的。

19. Singularity： 奇點，是時空無限彎曲的那一個點，一般認為存在于黑洞中央，可以看成空間時間的邊緣；Ray Kurzweil： 雷·庫茲韋爾（1948— ），現任谷歌工程總監，發明家、企業家，在人工智能、機器人等領域被視為奇才。