我們對(duì)暗能量的所有了解可能都是錯(cuò)誤的

我們對(duì)暗能量的所有了解可能都是錯(cuò)誤的

Dark energy is a theoretical form of energy that physicists use to explain how our universe appears to be expanding at an accelerated rate. It's a hypothesis that has gone from seeming like a suspicious physics "cheat," to now becoming widespread accepted cosmology.

暗能量是一種理論形式的能量，物理學(xué)家用它來(lái)解釋我們的宇宙是如何以加速的速度膨脹的。這一假說(shuō)從表面上看起來(lái)像是一個(gè)可疑的物理學(xué)“騙子”，到現(xiàn)在已經(jīng)成為廣泛接受的宇宙學(xué)。

This shows how luminosity evolution merely mimics dark energy in supernova (SN) cosmology. (Photo: Yonsei University)

But a theory-shattering new paper now threatens to throw dark energy right back into the realm of speculation. It turns out, the most direct and strongest evidence we have for dark energy to date looks to be based on a faulty assumption, reports Phys.org.

但是一篇打破理論的新論文現(xiàn)在威脅要把暗能量重新扔回猜測(cè)的領(lǐng)域。據(jù)Phys.org網(wǎng)站報(bào)道，到目前為止，我們所掌握的關(guān)于暗能量最直接、最有力的證據(jù)似乎是建立在一個(gè)錯(cuò)誤的假設(shè)上。

Dark energy catapulted into mainstream thought in 1998 after landmark distance measurements using type Ia supernovae for galaxies at high redshift showed that the more distant a galaxy is, the faster it appears to be moving away from us. This formed the core evidence for the idea that our universe must be expanding at an accelerated rate. It was such a landmark discovery that this research led to the 2011 Nobel Prize in Physics.

1998年，在利用Ia型超新星對(duì)處于高紅移的星系進(jìn)行里程碑式的距離測(cè)量后，暗能量一躍成為主流思想。測(cè)量結(jié)果表明，星系距離我們?cè)竭h(yuǎn)，它離我們?cè)竭h(yuǎn)的速度越快。這為我們的宇宙一定在加速膨脹的觀點(diǎn)提供了核心證據(jù)。這是一個(gè)里程碑式的發(fā)現(xiàn)，這項(xiàng)研究也因此獲得了2011年諾貝爾物理學(xué)獎(jiǎng)。

But it might be all wrong. A team of astronomers at Yonsei University in South Korea have shown that those distance measurements using type Ia supernovae are probably in error.

但這可能是完全錯(cuò)誤的。韓國(guó)延世大學(xué)的一組天文學(xué)家已經(jīng)證明，使用Ia型超新星測(cè)量距離可能是錯(cuò)誤的。

A new paper threatens to push our theory on dark energy back into the realm of speculation. (Photo: Buslik/Shutterstock)

"Quoting Carl Sagan, 'extraordinary claims require extraordinary evidence,' but I am not sure we have such extraordinary evidence for dark energy. Our result illustrates that dark energy from SN cosmology, which led to the 2011 Nobel Prize in Physics, might be an artifact of a fragile and false assumption," said project leader Prof. Young-Wook Lee.

“引用卡爾·薩根的話，‘非凡的主張需要非凡的證據(jù)’，但我不確定我們是否有關(guān)于暗能量的非凡證據(jù)。我們的研究結(jié)果表明，2011年諾貝爾物理學(xué)獎(jiǎng)得主——SN宇宙學(xué)的暗能量，可能是一個(gè)脆弱和錯(cuò)誤假設(shè)的產(chǎn)物。

By "SN cosmology," Lee is referring directly to the types of conjecture that emerged from that Nobel-winning research. The key assumption made back then was that the corrected luminosity of type Ia supernovae would remain relatively constant even across the redshift (objects moving away from us appear to shift toward the red as the light gets stretched out with the increasing distance). That's what appears to be incorrect, however.、

通過(guò)“SN宇宙學(xué)”，李直接提到了從那項(xiàng)獲得諾貝爾獎(jiǎng)的研究中產(chǎn)生的猜想類型。當(dāng)時(shí)做出的關(guān)鍵假設(shè)是，Ia型超新星的修正光度即使在紅移過(guò)程中也會(huì)相對(duì)保持不變(當(dāng)光線隨著距離的增加而拉長(zhǎng)時(shí)，遠(yuǎn)離我們的物體似乎會(huì)向紅色移動(dòng))。然而，這似乎是不正確的。

The Yonsei team performed high-quality spectroscopic observations of nearby host galaxies of type Ia supernovae. They found a significant correlation between the luminosity of these supernovae and stellar population age, at a 99.5 percent confidence level. What this means is that previous research did not account properly for the fact that the supernovae in host galaxies are getting younger with redshift (which is also a look back in time).

延世大學(xué)的研究小組對(duì)附近Ia型超新星的主星系進(jìn)行了高質(zhì)量的光譜觀測(cè)。他們發(fā)現(xiàn)，這些超新星的光度與恒星的年齡之間存在顯著的相關(guān)性，其置信度為99.5%。這意味著以前的研究沒有很好地解釋這樣一個(gè)事實(shí)，即隨著紅移(這也是對(duì)時(shí)間的回顧)，主星系中的超新星變得越來(lái)越年輕。

When properly taken into account, the luminosity evolution of these supernovae essentially cancels out the need to postulate dark energy. In other words, maybe our universe isn't expanding at an accelerated rate after all.

如果適當(dāng)?shù)丶右钥紤]，這些超新星的光度演化基本上就抵消了對(duì)暗能量假設(shè)的需要。換句話說(shuō)，也許我們的宇宙并不是在加速膨脹。

It's a humbling reminder of how our grand cosmological theories are often held together by a very delicate house of flimsy cards. There's only so much we can observe from our little blue home in a corner of the vast cosmos; we have to extrapolate a lot with only a thin slice of data to go on. While our theories are always advancing, it's foolhardy to believe that the information we have today is sufficient for achieving final answers to the big questions.

它謙卑地提醒我們，我們偉大的宇宙學(xué)理論往往是由脆弱的卡片組成的精致的房子連接在一起的。在浩瀚宇宙的一角，我們小小的藍(lán)色家園所能看到的只有這么多;我們只能用很少的數(shù)據(jù)來(lái)進(jìn)行大量的推斷。雖然我們的理論一直在進(jìn)步，但認(rèn)為我們今天掌握的信息足以最終解決大問(wèn)題，這是很愚蠢的。

While that might mean we have to go back to the drawing board, it also means we've got much more left to discover. That's what makes doing science so enthralling: the further along we get, the longer we have yet to go.

雖然這可能意味著我們必須從頭開始，但這也意味著我們還有更多的東西需要去發(fā)現(xiàn)。這就是科學(xué)之所以如此迷人的原因:我們走得越遠(yuǎn)，那么還要走的就越長(zhǎng)。