美国科学家称宇宙将在未来37亿年内毁灭

　　A new study suggests the universe and everything in it could endwithin the Earth's lifespan - less than 3.7 billion years from now - andwe won't know it when it happens. But one expert says the result isn'tvalid。

　　The universe began in a Big Bang about 13.7 billion years ago andhas been expanding at an ever accelerating rate ever since. According tostandard cosmology models the most likely outcome for the universe isthat it will expand forever. But a team of physicists led by RaphaelBousso from the University of California, Berkeley, claim theircalculations show the universe will end。

　　Bousso and colleagues say there's a "measure problem" in thecosmological theory of eternal inflation. Eternal inflation is a quantumcosmological model where inflationary bubbles can appear out ofnothing. Some expand and go on forever, others collapse and disappearagain. These bubbles, each being a universe, pop in and out of existencelike bubbles in boiling water。

　　They argue, in an eternally inflating universe, every event that ispossible will eventually occur - not just once, but an infinite numberof times. This makes predicting when each event will occur impossible,such as the probability that a universe like ours exists。

　　Bousso's team have being trying to determine the number of bubblesthat exist at any given time and the number of "observers" in eachbubble to come up with the relative frequency of observers that can livein one universe compared to the relative frequency of observers who canlive in another universe. But the "measure problem" makes calculatingthis value impossible。

　　According to Bousso and colleagues, the only way to avoid thisconundrum is to introduce a cut-off point, which then helps make senseagain. By introducing this cut-off, they say there is "a 50-50 chance ofthe universe ending in the next 3.7 billion years."

　　However, Charles Lineweaver from the Australian NationalUniversity's Mount Stromlo Observatory says Bousso's team are simplyimposing a catastrophe for statistical reasons. He says the need for abetter statistical solution has led the researchers to a falseconclusion about the end of the universe. "Bousso's average life of auniverse is a set time, only because that's what happens when youintroduce a cut off point to get a reasonable probability," he said。

　　“发现新闻”网8日报道称，最新一项研究结果表明，宇宙及宇宙万物寿命将短于地球寿命——在未来37亿年内毁灭——而且我们不知道这将在什么时候发生。不过，有专家称该结论并不可靠。

　　宇宙形成于大约137亿年前的大爆炸，从此开始加速膨胀。根据标准的宇宙学模型，宇宙最有可能的结局是永远膨胀下去。然而，美国加州大学伯克利分校物理学家拉斐尔-布索领导的一个研究小组却宣称，根据他们的计算结果，宇宙终将走向灭亡。

　　布索和同事称在宇宙永远膨胀理论中存在一个“计量问题”。永久膨胀是由量子宇宙学模型得出的结论，在这个模型中，膨胀的气泡可以随意出现和消失。有些气泡会膨胀并永远膨胀下去，而其他的则会破裂消失。每一个气泡好比一个宇宙，这些气泡像沸水中的水泡一样，都是在爆裂声后突然出现或突然消失。

　　他们称，在一个无限膨胀的宇宙里，但凡有可能发生的事情终将发生——不是一次，而是无穷多次。预测事件便毫无必要，比如与我们这个宇宙的另外一个世界存在便不成为问题。

　　布索的团队已经尝试着努力测试在给定时间内的气泡数目以及在每一个气泡中“观测者”的数目，这样做的目的是对比生活在某一宇宙中观察者的相对频率和生活在另一个宇宙中的观察者的相对频率。但是，“测量问题”使得得到计算结果变得不可能。

　　据布索和同事所述，唯一能够避免这个难题的途径是引入一个的截点，这样有助于解决问题。通过引入截点，他们说“宇宙将会在接下来的37亿年内有50%的可能性走向毁灭”。

　　然而澳大利亚国立大学斯壮罗山天文台的天体生物学家查尔斯-林尼韦弗博士说，仅因为统计方面的原因，布索的研究小组可能正在带来一场灾难。他宣称，寻求找到一个更好的统计学解决方案的必要性使得布索及其同事对宇宙结局做出了错误的结论。“布索对宇宙平均寿命的估计是一个固定的时间，因为只有引入截点来得到一个合理的可能性时，这一切才会发生，”他说。