* 【essie 湯】
“I believe things can't make themselves impossible. If they could then there'd be nothing to stop the whole universe from descending into chaos.”
－Stephen W. Hawking
這些亙古未解的謎團，讓英國物理學家史蒂芬．霍金（Stephen W. Hawking）用一生心力不斷思索探尋。他對宇宙和萬物的研究，往往深具突破性，把許多乍聽像是不可能且難以想像的事物，賦予合理而深入的解釋，霍金也被世人譽為繼愛因斯坦之後最傑出的理論物理學家。
霍金最著名的一本著作，是於1988年出版的《時間簡史》（A Brief History of Time）。此書解釋宇宙（the Universe）、黑洞（Black Holes）和大爆炸（Big Bang）等天文物理學理論，刷新人類的視野，該書堪稱是當今全球最暢銷的科普著作之一，但也因為書中內容艱澀難懂，被西方媒體戲稱為「讀不了的暢銷書」（a unreadable best-seller）。
●以下節錄英國《時代雜誌》（The Times UK）針對霍金的外星人存在論點所做的報導：
Stephen Hawking thinks alien civilizations may well exist and warns that if we Earthlings know what's good for us, we'll stop trying to contact them.
Hawking's Discovery Channel documentary hypothesizes some very strange looking reptilian and aquatic creatures. Such scenes are speculative, but Hawking uses them to lead on to a serious point that a few life forms could be intelligent and pose a threat. Hawking believes that contact with such a species could be devastating for humanity.
He suggests that aliens might simply raid Earth for its resources and then move on, “We only have to look at ourselves to see how intelligent life might develop into something we wouldn't want to meet. I imagine they might exist in massive ships, having used up all the resources from their home planet. Such advanced aliens would perhaps become nomads, looking to conquer and colonize whatever planets they can reach.”
He concludes that trying to make contact with alien races is “a little too risky”. He said, “If aliens ever visit us, I think the outcome would be much as when Christopher Columbus first landed in America, which didn't turn out very well for the Native Americans.”
“Time flows like a river and it seems as if each of us is carried relentlessly along by time's current. But time is like a river in another way. It flows at different speeds in different places and that is the key to travelling into the future…The satellites make satellite navigation possible. But they also reveal that time runs faster in space than it does down on Earth…And this startling reality is what opens the door to the possibility of time travel to the future.”
“There's a cosmic speed limit, 186,000 miles per second, also known as the speed of light…Imagine a track that goes right around Earth, a track for a superfast train…When the power is turned on, they (staff on the train) accelerate from zero to 60,000mph in a fraction of a second. Increase the power and the particles go faster and faster, until they're whizzing around the tunnel 11,000 times a second, which is almost the speed of light. But just like the train, they never quite reach that ultimate speed. They can only get to 99.99 percent of the limit. When that happens, they too start to travel in time.”
“It really is that simple. If we want to travel into the future, we just need to go fast. Really fast. And I think the only way we're ever likely to do that is by going into space. The fastest manned vehicle in history was Apollo 10. It reached 25,000mph. But to travel in time we'll have to go more than 2,000 times faster. And to do that we'd need a much bigger ship, a truly enormous machine. The ship would have to be big enough to carry a huge amount of fuel, enough to accelerate it to nearly the speed of light. Getting to just beneath the cosmic speed limit would require six whole years at full power.”
霍金的學術成就和專業領域廣受矚目，但更為人動容的是，他克服先天的運動神經元疾病，更證明了「凡事皆有可能」（Nothing is impossible）的「霍金精神」。他在求學期間發現得到「肌萎縮側索硬化症」（amyotrophic lateral sclerosis, ALS）、俗稱「漸凍人」的疾病。ALS會侵襲腦部和脊髓的神經細胞，導致肌肉無力，說話、吞嚥及呼吸困難，最終全身癱瘓。當時醫生宣布他只剩3年的生命，但他打破了死亡預言存活下來，而且即使全身癱瘓，不能發音，他還是用一台特製的電腦聲音合成器，和幾個稍能活動的手指，緩慢地用簡單拼音來操縱合成器，藉以表達思想，完成一系列關於大爆炸和黑洞的驚人理論，對量子物理作出了巨大的貢獻。霍金的成就，不僅代表了人類思想的奇蹟，也是人文精神的勝利。
“Although there was a cloud hanging over my future, I found, to my surprise, that I was enjoying life in the present more than before…I have been lucky that my condition has progressed more slowly than is often the case. But it shows that one need not lose hope.”
「肌萎縮側索硬化症」（ALS）Amyotrophic Lateral Sclerosis (ALS), often referred to as “Lou Gehrig's Disease,“ is a progressive neurodegenerative disease that affects nerve cells in the brain and the spinal cord. Motor neurons reach from the brain to the spinal cord and from the spinal cord to the muscles throughout the body. The progressive degeneration of the motor neurons in ALS eventually leads to their death. When the motor neurons die, the ability of the brain to initiate and control muscle movement is lost. With voluntary muscle action progressively affected, patients in the later stages of the disease may become totally paralyzed.