※ 本文為 MindOcean 轉寄自 ptt.cc 更新時間: 2016-06-23 19:28:48
看板 Gossiping
作者 標題 [爆卦] 宇宙大小被估測出來了
時間 Thu Jun 23 12:31:19 2016
原文連結：
http://goo.gl/N891CD
BBC - Earth - It took centuries, but we now know the size of the Universe
![[圖]]()
The sheer scale of the cosmos is hard to imagine, and even harder to put an accurate figure on. But thanks to some ingenious physics we now have a goo ...
![[圖]](http://ichef.bbci.co.uk/wwfeatures/wm/live/624_351/images/live/p0/3x/sw/p03xsw49.jpg)
"Let us go rambling about the Universe." This is the invitation that American astronomer Harlow Shapley gave to an audience in Washington DC in 1920. He was taking part in the so-called Great Debate with fellow scientist Heber Curtis on the scale of the Universe.
Shapley believed that our Milky Way galaxy was 300,000 light years across. That is actually three times too big according to the latest thinking, but his measurements were pretty good for the time. In particular, he calculated broadly correct proportional distances within the Milky Way – the position of our Sun relative to the centre of the galaxy, for instance.
In the early 20th Century, though, 300,000 light years seemed to many of Shapley's contemporaries an almost absurdly large figure. And the idea that other Milky Way-like spiral galaxies – which could be seen with telescopes – were equally large was outlandish.
Indeed, Shapley himself believed the Milky Way must be exceptional. "Even if the spirals are stellar, they are not comparable in size with our stellar system," he told his listeners.Curtis disagreed. He thought, correctly, that there were many other galaxies as big as our own spread throughout the Universe. But, interestingly, his starting point was a belief that the Milky Way was far smaller than Shapley had calculated. According to the calculations that Curtis used, the Milky Way was just 30,000 light years in diameter – or, about three times too small going on modern measurements.
Three times too big; three times too small – when we are talking about such enormous distances it is understandable that astronomers debating almost a century ago could get their figures a little bit wrong.
Today we are fairly confident that the Milky Way is probably between 100,000 and 150,000 light years across. The observable Universe is, of course, much larger. According to current thinking it is about 93 billion light years in diameter. How can we be so sure? And how did we ever come up with such measurements from right here on Earth?
Ever since Copernicus argued that the Earth was not the centre of the Solar System, it seems we have always found it difficult to rewrite our preconceptions of what the Universe is – and especially, how big it may be. Even today, as we will see, we are gathering new evidence to suggest the whole Universe may be much bigger than some have recently thought.
Caitlin Casey, an astronomer at the University of Texas at Austin, studies the Universe as we know it. As she points out, astronomers have developed an ingenious array of tools and measuring systems to calculate not just the distance from Earth to other bodies in our Solar System, but the spans between galaxies and the journey to the edge of the observable Universe itself.
The steps to measuring all these things are known as the "cosmic distance ladder". The first rung of the ladder is easy enough for us to get onto and these days it relies on modern technology.
"We can just bounce radio waves off of neighbouring planets in the Solar System, like Venus and Mars, and measure the time it takes for those waves to come back to Earth," says Casey. "That gives us a very precise measurement."
Big radio telescopes like Arecibo in Puerto Rico can do this sort of work – but they can also do even more than that. Arecibo, for instance, can detect asteroids flying around the Solar System and even produce images of them based on how radio waves reflect off the asteroid's surface.
But using radio waves to measure distances beyond our Solar System is not practical. The next rung on the cosmic distance ladder is something known as parallax measurement.This is also something we do all the time without realising. Humans, like many animals, intuitively recognise the distance between themselves and objects, thanks to the fact that we have two eyes.
If you hold an object in front of you – say your hand – and look at it with one eye open, then switch to using only the other eye, you will see your hand appears to shift sideways slightly. This is called parallax. The difference between those two observations can be used to work out the distance to the object in question.
Our brains do it naturally with the information from both our eyes, and astronomers do exactly the same thing with nearby stars, except they use different sensors: telescopes.Imagine having two eyes floating in space, either side of our Sun. Thanks to the Earth's orbit, that is exactly what we do have, and we can view stars' shift relative to objects in the background by this method.
"We take a measurement of where stars are in the sky, say, in January and we wait six months and measure those same stars in July, when we're on the opposite side of the Sun," says Casey.
However, there is a point at which objects are so far away – about 100 light years – that the observed shift is too small to provide a useful calculation. At this distance, we are still nowhere near the edge of our own galaxy.
The next step up is a technique called "main sequence fitting". It relies on our knowledge of how stars of a certain size – known as main sequence stars – evolve over time.For one thing, they change colour, gradually becoming redder with age. By measuring their colour and brightness accurately, and then comparing this to what is known about the distance of closer main sequence stars measurable by parallax, we can estimate the positions of these more distant stars.
The principle that backs these calculations is that which states that stars of the same mass and age would appear equally bright were they the same distance from us. Since they are often not, we can use the difference in those measurements to work out how far away they actually are.
Main sequence stars, when used for this analysis, are considered one type of "standard candle" – meaning a body whose magnitude (or brightness) we can calculate mathematically. These candles are dotted around space, lighting the Universe in predictable ways. But main sequence stars are not the only examples.
This understanding of how brightness relates to distance is pretty fundamental to working out the distance to even farther objects – like stars in other galaxies. Main sequence fitting will not work there, though, because the light from those stars – which are millions of light years away if not more – is hard to analyse with accuracy.
But way back in 1908, a scientist called Henrietta Swan Leavitt at Harvard came up with a fantastic discovery that has helped us measure such colossal distances. Swan Leavitt realised that there was a special class of stars called Cepheid variables.
"She made this observation that a certain type of star varies its brightness over time, and the variation in the brightness, the pulsations of these stars, relates directly to how bright they are intrinsically," says Casey.
In other words, a brighter Cepheid will "pulsate" more slowly (over the course of many days, in fact) than a dimmer Cepheid. Because astronomers can measure the pulse of a Cepheid relatively easily, they can predict how bright the star is. Then, by observing how bright it actually appears to us, they can calculate its distance.
This is similar in principle to the main-sequence fitting approach, in that brightness is again the key. But the key point is that distance can be measured in different ways. And the more ways of measuring distances we have, the better we can understand the true scale of our cosmic backyard.
It was the detection of such stars in our own galaxy that convinced Harlow Shapley of its great size.
In the early 1920s, Edwin Hubble detected Cepheid variables in the nearby Andromeda galaxy and discerned that it was just under a million light years away.
Today, our best estimate is that the galaxy is actually 2.54 million light years away. But that does not shame Hubble's measurement. In fact, we are still trying to work out a best estimate for the distance to Andromeda. The 2.54 million light years figure is actually an average of several recent calculations.
This is the point at which the sheer scale of the Universe, even now, continues to boggle our minds. We can make very good estimates, but in truth it is extremely difficult to measure distances between galaxies with fine accuracy. The Universe really is that big. And it does not stop there.
Hubble also measured the brightness of exploding white dwarf stars – Type 1A supernovas. These can be seen in quite distant galaxies, billions of light years away.Because the brightness of these explosions is calculable, we can determine how far away they are, just like we can with Cepheid variables. The Type 1A supernovas and Cepheid variables, then, are both additional examples of what astronomers call standard candles.
But there is one more feature of the Universe that can help us to measure really extreme distances. It is called redshift.If an ambulance or police car blaring a siren has ever passed you in the street, you will be familiar with the Doppler Effect. As the ambulance approaches you the siren seems high in pitch and then, as it passes you and moves away, it falls again.
The same thing happens with light waves, on a much finer scale. We can detect the change by analysing the spectrum of light from distant bodies. This spectrum will have dark lines in it because some specific colours are absorbed by elements in and around the light source – the surface of stars, for example.
The further away objects are from us, the further towards the red end of the spectrum those lines will be shifted. That is not just because the objects are far away, but because they are actually moving further away from us over time, thanks to the Universe's expansion. And seeing redshift in the light from distant galaxies is one way of proving that the Universe is, indeed, expanding.
It is like putting dots on the surface of a balloon – each representing a galaxy – and then blowing up the balloon, says Kartik Sheth, a programme scientist at NASA. As the balloon expands the distance between the dots on its surface grows. "As the Universe is expanding, each galaxy is moving away from the others."
"Basically, a wave would normally just be whatever frequency it was emitted at, but now you're stretching space-time itself so therefore the wave looks longer."The faster that galaxy is moving from us, the further away it must be – and the more redshifted its light will be when we analyse it back here on Earth. Again, it was Edwin Hubble who discovered that there was a proportional relationship between his Cepheids in distant galaxies and how much the light from those galaxies was redshifted.
Now comes the big key to our puzzle. The most redshifted light we can detect in the observable Universe suggests that light has reached us from galaxies that are 13.8 billion years old.Because this is the oldest light we have detected, that also gives us a measurement for the age of the Universe itself.
But over the last 13.8 billion years, the Universe has been continually expanding – and at first it did so very rapidly. Taking that into account, astronomers have worked out that the galaxies right on the edge of the observable Universe, whose light has taken 13.8 billion years to reach us, must now be 46.5 billion light years away.
That is our best measurement for the radius of the observable Universe. Doubling it, of course, gives the diameter: 93 billion light years.This figure rests on many other measurements and bits of science, and it is the culmination of centuries of work. But, as Casey notes, it is still a little rough.
For one thing, given the complexity of some of the oldest galaxies we can detect, it is not clear how they were able to form so quickly after the Big Bang. One possibility is that, somewhere, a few of our calculations are not quite right.
"If one of the rungs of the cosmic distance ladder is off by 10%, then everything's off by 10%, because they rely on each other," says Casey.And where things get really complex is when we try to think about the Universe beyond that which is observable. The "whole" Universe, as it were. Depending on which theory of the shape of the Universe you prefer, the whole Universe could actually be finite or infinite.
Recently, Mihran Vardanyan and colleagues at the University of Oxford in the UK analysed known data about objects in the observable Universe, to see if they could work out anything about the shape of the whole Universe.
The result, after using computer algorithms to look for meaningful patterns in the data, was a new estimate. The whole Universe is at least 250 times as large as the observable Universe.We can never see these more distant regions. Still, the observable Universe alone should be big enough for most people. Indeed, for scientists like Casey and Sheth, it remains a constant source of fascination.
"Everything that we've learned about the Universe – how big it is, all the amazing objects that are in it – we do that simply by collecting these photons of light that have travelled millions and millions of light years only to come and die on our detectors, our cameras or radio telescopes," says Sheth.
"It's rather humbling," says Casey. "Astronomy has taught us that we're not the centre of the Universe, we're not even at the centre of our Solar System or at the centre of our galaxy."
One day, we might travel physically much further into the Universe around us than we have so far dreamed. For now, we can only look. But just looking can let us ramble pretty far.Join over five million BBC Earth fans by liking us on Facebook, or follow us on Twitter and Instagram.
If you liked this story, sign up for the weekly bbc.com features newsletter called "If You Only Read 6 Things This Week". A handpicked selection of stories from BBC Future, Earth, Culture, Capital, Travel and Autos, delivered to your inbox every Friday.
目前的觀測數據平均值
宇宙的直徑大概有930億光年
你可以說祂無限大
也可以說祂有限大
就看你要用什麼理論看待/檢驗這宇宙
^.<
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推 : 跟我算出來的差不多1F 06/23 12:31
→ : (づ′・ω・）づ 原來= =2F 06/23 12:31
→ : 跟我想的一樣3F 06/23 12:31
→ : 喔4F 06/23 12:31
→ : 喔 是喔5F 06/23 12:31
→ : 比大覺者還大6F 06/23 12:31
推 : 大宇宙7F 06/23 12:31
推 : 先推 免得別人說我看不懂8F 06/23 12:32
→ : 觀測大小哪裡等於實際大小?9F 06/23 12:32
→ : 好長喔10F 06/23 12:32
推 : 嗯嗯 昨天睡前也是這麼想11F 06/23 12:32
→ : 納超過930億光年後會是什麼?12F 06/23 12:32
推 : 我前幾年就推出來了13F 06/23 12:32
推 : 好無聊 幾億輩子都沒辦法探索的空間14F 06/23 12:32
→ brella …
噓 : 早就知道了16F 06/23 12:32
推 : 這麼短，五樓尻一槍的時間就到惹17F 06/23 12:32
推 : 跟我一樣長18F 06/23 12:32
推 : 先推 免得人說我看不懂19F 06/23 12:32
推 : 跟我差不多20F 06/23 12:32
推 : 這不是可觀測尺度而已嗎？21F 06/23 12:32
推 : 跟我想的差不多22F 06/23 12:33
推 : 是虛空之遺 薩爾納迦23F 06/23 12:33
推 : 外星人母艦比太平洋大，真的不誇張24F 06/23 12:33
→ : 觀測的宇宙數量不夠，不符合統計概念，扣分25F 06/23 12:33
噓 : 不信 宇宙壽命才150億年 大小930億光年? 超過150億光年26F 06/23 12:33
推 : 嗯嗯 原來是這樣27F 06/23 12:33
推 : 剛剛在苦讀四則運算的時候有算出來28F 06/23 12:33
噓 : 跟我起床尿尿算的差不多29F 06/23 12:33
推 : 和我上次想的一樣30F 06/23 12:33
→ : 外宇宙： 你的小宇宙 也敢拿出來跟大家比哦31F 06/23 12:34
→ : 那外星人從土星飛到地球要多久...32F 06/23 12:34
→ : 的資訊到到不了 是怎麼推的?33F 06/23 12:34
推 : 不合理34F 06/23 12:34
噓 : 宇宙的旁邊是蛇某?旁邊的旁邊又是什抹?35F 06/23 12:34
推 : 現在才算出來有什麼好嘴的36F 06/23 12:34
→ : 這我上輩子就知道了，結果現在還公停留在這階段37F 06/23 12:34
噓 : 沒看過七龍珠喔 有12個宇宙好嗎38F 06/23 12:34
→ : 原來如此39F 06/23 12:35
→ : 先證明沒有平行宇宙再說40F 06/23 12:35
推 : 這我早就知道了只是忘了說而已41F 06/23 12:35
推 : 這種事情，還是請示一下上人比較好42F 06/23 12:35
→ : 我們宇宙的大小,只是遠古外星人世界裡微生物大小的等級?43F 06/23 12:35
→ : 反正又證實不了~~44F 06/23 12:35
推 : 比我懶叫小一點 還算OK45F 06/23 12:36
噓 : 宇宙的外面是一間肥宅的房間46F 06/23 12:36
→ : 這算錯了我的理論是宇宙之外還有宇宙的，只是懒得發表文章47F 06/23 12:36
→ : seefood早就開示過惹48F 06/23 12:36
→ : 哦哦 這跟我之前想的差不多49F 06/23 12:36
推 : 怎麼有人有宇宙一億年膨脹一億光年的錯覺XD50F 06/23 12:36
推 : 有待商榷，我也是覺得不太合理...應該無邊際才對。不然51F 06/23 12:37
→ : 照這樣說，邊際的隔壁會是什麼？另一個宇宙？？
→ : 照這樣說，邊際的隔壁會是什麼？另一個宇宙？？
推 : 宇宙會不會是圓的53F 06/23 12:37
推 : 930*3*10^8*60*60*24*356 的距離54F 06/23 12:37
→ : 小宇宙外面是宇宙，宇宙外?是宇宙。釋迦摩尼佛說過：一粒55F 06/23 12:37
推 : 嗯嗯 跟我想的一樣56F 06/23 12:37
→ : 沙有三千大千世界(非原話)，依照生命層次決定你能瞭解的宇57F 06/23 12:37
推 : 台灣老闆認為這無法增加GDP沒有意義58F 06/23 12:38
推 : 宇宙是圓的 那宇宙外面又是什麼59F 06/23 12:38
推 : 跟我想的一樣大60F 06/23 12:38
→ : 宇宙應該只是外星肥宅房間裡面的一顆灰塵吧61F 06/23 12:38
→ : 宙範圍，簡單說佛外還有佛，更高的佛，大概如此62F 06/23 12:38
推 : 嗯嗯 跟我想的一樣63F 06/23 12:38
→ : 所以宇宙大小不會膨脹變大嗎？64F 06/23 12:38
→ : 所以有宇宙邊緣人嗎65F 06/23 12:38
→ : 嗯 跟我估算的有0.00001%誤差 可是不錯了66F 06/23 12:38
推 : 應該是此宇宙吧 不同次元還有其他宇宙67F 06/23 12:38
推 : 為什麼要有邊際 你在地球表面找邊際試試看68F 06/23 12:38
→ : 能夠量化的一定是有限大69F 06/23 12:39
→ : 這不是常識嗎70F 06/23 12:39
推 : 為什麼宇宙的直徑會比宇宙的年齡x2大這麼多？ 這不是意71F 06/23 12:39
推 : 好險我都看的懂72F 06/23 12:39
→ : 謂著宇宙擴張速度大於光速嗎？73F 06/23 12:39
推 : 趕快推以免別人覺得我看不懂74F 06/23 12:39
推 : 常識+175F 06/23 12:39
推 : 宇宙外面還有什麼啊76F 06/23 12:39
噓 : 不懂哪裡有掛...77F 06/23 12:39
推 : 最後發現 我們只是被外星人養在實驗室培養皿裡的實驗生物78F 06/23 12:39
推 : 跟我的大覺者一樣長79F 06/23 12:40
噓 : 跟我想的一樣 抄我的吧80F 06/23 12:40
推 : 也許這個宇宙只是台灣大小呢，其他宇宙存在的可能性?81F 06/23 12:40
→ : 佛說的就唬爛而已 西方在宇宙中是哪一方82F 06/23 12:40
→ : 哪裡有賣宇宙模型？83F 06/23 12:40
推 : 這只是可觀測宇宙而已啊84F 06/23 12:40
噓 : 補充一下 九百多億的說法好幾年前就有了85F 06/23 12:41
→ ubike5566 …
推 : 還用你說?87F 06/23 12:41
推 : 沒什麼 跟5樓的寶劍差不多長88F 06/23 12:41
推 : 還在繼續膨脹中 宇宙紅移89F 06/23 12:42
→ : 可觀測應該只有一百多億 九百多億是用其他方法估算的90F 06/23 12:43
→ : 而且應該是至少九百多億 可能會更大
→ : 而且應該是至少九百多億 可能會更大
→ : 並可能有多重宇宙92F 06/23 12:43
推 : wsx大說的是某黨的黨產吧93F 06/23 12:43
推 : 還不發射什麼鬼波讓外星人來泥巴球玩玩94F 06/23 12:43
→ : 恩恩，跟我想得差不多95F 06/23 12:43
→ : 直徑....宇宙是球體嗎?96F 06/23 12:43
推 : 趕快推，要不然人家以為我看不懂97F 06/23 12:44
推 : 宇宙大 房價怎麼還是那麼貴98F 06/23 12:44
→ : 他說的直徑應該是可觀測的範圍 並不是指宇宙99F 06/23 12:45
→ : D碟被刪的那一瞬間不就都知道了？100F 06/23 12:45
推 : 這不是我十年前的論文嗎？101F 06/23 12:45
→ : 所以這篇的原PO總結問題很大102F 06/23 12:46
→ : 還是說宇宙只是外星小屁孩參加科展的實驗模型?103F 06/23 12:46
→ : 我查資料是說 九百多億的說法是用宇宙背景輻射算的104F 06/23 12:46
→ : 西方是用人能理解方式說明，佛在西道在東。地球在旋轉，銀105F 06/23 12:46
→ : 河系也在旋轉，哪有東南西北之分。用人的想法很難理解高層
→ : 河系也在旋轉，哪有東南西北之分。用人的想法很難理解高層
→ : 可見光的話應該只有一百四十億左右107F 06/23 12:47
→ : 生命的思想108F 06/23 12:47
推 : 嗯？ 宇宙之外有109F 06/23 12:48
→ : 跟我想得差不多110F 06/23 12:48
推 : 930億外面那一公分是什麼東西?111F 06/23 12:48
→ : 嗯 跟我想的差不多112F 06/23 12:48
推 : 反正還會繼續大113F 06/23 12:49
推 : 930億光年算什麼，用yoyo航空器，一下就能繞到宇宙盡頭114F 06/23 12:49
推 : 嗯嗯，果然是這樣啊！（心虛）115F 06/23 12:49
→ : 附佛外道就是等人家科學研究出來才在拿自己講的穿鑿附會116F 06/23 12:49
噓 : 硬要扯宗教 邪門歪道的東西滾開117F 06/23 12:50
推 : 9.3× 10^10118F 06/23 12:50
推 : 差不多119F 06/23 12:50
→ : 為什麼算這麼久 計算機壞了嗎120F 06/23 12:51
推 : 大爆炸後的時空相對也會膨脹 所以會>138yee121F 06/23 12:51
推 : 外面就暗黑大陸啊 沒看獵人嗎122F 06/23 12:52
推 : 但你媽的大小還在觀測中123F 06/23 12:53
→ : 比我媽還瘦124F 06/23 12:53
推 : 幹這不是很久以前就知道了= =“125F 06/23 12:54
推 : 所以盡頭是甚麼126F 06/23 12:55
→ : 但我的小宇宙是無限的啊啊啊啊127F 06/23 12:55
→ :
→ :
推 : 他隨便說個數字一般人也不知道真假129F 06/23 12:55
推 : 930億光年裡，只有地球有生命存在的機率是多少？130F 06/23 12:57
推 : 哼 這我早就知道了131F 06/23 12:57
→ : 那最終點是道牆? 牆的後面是啥?132F 06/23 12:57
推 : 適合生命生存好像只有0.0000................0012%133F 06/23 12:58
噓 : = = 宇宙不是平的好嗎 盡頭不一定是一道障礙134F 06/23 12:59
→ : 連畢卡艦長都飛不了那麼遠，人類繼續反核下去，再過個50135F 06/23 12:59
→ : 要用(女神的驚嘆)打破才會知道136F 06/23 12:59
→ : 年連木星都沒辦法去137F 06/23 12:59
推 : 我就知道是這樣138F 06/23 12:59
→ : 反核團體就是外星人派來地球當間碟要把地球人關在地球圈139F 06/23 13:00
→ : 的幫兇!!!!!!!!
→ : 的幫兇!!!!!!!!
噓 : 所以盡頭的外面是甚麼141F 06/23 13:00
推 : 庫伯都告訴你有愛就能用重力蒿洨 是在核能發撒小電喇142F 06/23 13:00
噓 : 嗯嗯 郭p4143F 06/23 13:01
推 : 沒人反對，所以一定是真的144F 06/23 13:02
噓 : 算錯了 我當初造的時候有１萬光年這麼大145F 06/23 13:02
推 : 宇宙是(至少)4D的球體吧，這直徑怎麼算？146F 06/23 13:02
噓 : 還是說宇宙只是外星電腦模擬器跑出來的model?Y147F 06/23 13:06
推 : 有沒有很多人不知道光年是距離的八卦148F 06/23 13:08
推 : 佛經裡的"三千大千世界"就已說明宇宙多大了~149F 06/23 13:09
推 : 靠北 我算的差兩億光年150F 06/23 13:09
→ : END151F 06/23 13:09
推 : 跟我用電腦小算盤算的差不多152F 06/23 13:12
→ : 看看就好 反正觀測這早就超過地球人的能力範圍惹153F 06/23 13:13
推 : 像弦論一樣無法觀測吧！154F 06/23 13:13
→ : 930憶喔 你慢慢跑 就算是有限也永遠沒人知道外面是155F 06/23 13:14
→ : 啥 基本上無限已經沒區別了
→ : 啥 基本上無限已經沒區別了
→ : 跟我想的差不多157F 06/23 13:15
噓 : 噓某樓 壽命跟大小 哪有關係158F 06/23 13:16
推 : 我小學就知道了159F 06/23 13:20
推 : 摁摁 跟我想的差不多160F 06/23 13:28
→ : 嗯嗯161F 06/23 13:29
→ : 跟我的屁眼差不多大162F 06/23 13:33
→ : 嗯嗯 原來是醬163F 06/23 13:34
→ : 話說這要怎麼驗證阿? 觀測光又沒走完900多億得時間164F 06/23 13:37
推 : 亂講我也不知道165F 06/23 13:37
→ : 唬一下就好了 反正沒人知道166F 06/23 13:38
推 : 我說正確的是932億光年 誰能反駁我167F 06/23 13:40
→ : 跟我算出來的差不多168F 06/23 13:40
推 : end169F 06/23 13:40
推 : 我也這樣想170F 06/23 13:41
推 : 是球體？171F 06/23 13:48
推 : 趕快推，免得被說看不懂172F 06/23 13:50
推 : 所以碰到底會怎樣 有牆壁嗎173F 06/23 13:51
→ rex9999 …
推 : 從大霹靂用光速走150億年也才150光年而已欸175F 06/23 13:55
→ : 150億
→ : 150億
推 : 先推 免得人說我看不懂177F 06/23 13:57
推 : 跟我算的差不多178F 06/23 13:58
推 : 我的想法被抄襲了179F 06/23 14:01
推 : 壽命跟大小一樣嗎zzz壽命150億光年就不能膨脹成930億光180F 06/23 14:08
→ : 年了?_?
→ : 年了?_?
推 : 問題是他在量測的過程中宇宙也在擴張182F 06/23 14:10
Chiphell-nApoleon… | 自由微博
Chiphell-nApoleon：某爱国人士真实地情感流露~[生病] ...
Chiphell-nApoleon：某爱国人士真实地情感流露~[生病] ...
→ : 文章早就提出了XD 比中華四維拓墣帝國還小一點184F 06/23 14:14
推 : 未看先猜有跟我想的一樣185F 06/23 14:20
推 : 我只關心眼前正妹的罩杯多大186F 06/23 14:20
→ : 先推免得我看不懂187F 06/23 14:26
推 : 這很難算？188F 06/23 14:29
推 : 宇宙邊緣人表示寂寞189F 06/23 14:31
推 : 朕知道了190F 06/23 14:31
推 : 宇宙的開展 比光速快191F 06/23 14:32
推 : 估測…我估測比這個大6億倍說192F 06/23 14:32
推 : 在我的誤差範圍內193F 06/23 14:37
推 : 太神啦194F 06/23 14:45
※ alen84204:轉錄至看板 Physics 06/23 14:52
噓 : 通篇廢話 跟宇宙年齡說有87趴像195F 06/23 14:52
推 : 我幼稚園就做過計算了196F 06/23 15:04
→ : 這只是一個宇宙而已 你又知道有幾個宇宙了?197F 06/23 15:27
推 : 和我8.7歲時算出來的一樣,正確是932.571億光年198F 06/23 15:29
推 : 宇宙都量出來了 你老媽的體重還在計算中199F 06/23 15:29
→ : 跟我算的差不多~200F 06/23 15:31
推 : 還好啊 再讓我算一次宇宙會更大0.87光年201F 06/23 15:39
推 : 你媽超胖202F 06/23 15:54
→ : 快推免得別人以為我看不懂203F 06/23 16:07
→ : 這叫可觀測的邊界範圍，我們沒有能力確認那是不是確實大小204F 06/23 16:41
推 : 嗯，跟我想的一樣205F 06/23 16:43
推 : 宇宙外面呢206F 06/23 16:53
推 : 樓下絕對看不懂207F 06/23 17:13
→ : 才930億，黨產都不只9000億了208F 06/23 17:32
噓 : 說無限大的是智障?209F 06/23 17:41
→ foolfighter …
推 : 你不會去問全王喔211F 06/23 17:43
→ : 那是幾公里 開車要開多少天喇 說一下
→ : 那是幾公里 開車要開多少天喇 說一下
→ : 觀測距離跟實際大小沒啥關系吧213F 06/23 18:19
推 : 250倍可觀測宇宙大......真的假的214F 06/23 18:28
→ : 我才算931億光年 感覺他們算錯了215F 06/23 19:17
--
3樓 時間: 2016-06-23 13:42:17 (台灣)
→
(編輯過) TW
宇宙還在膨脹阿~接下來那一秒大概就是光繼續移動一秒的距離.....相對於930億光年一秒的距離根本忽略
4樓 時間: 2016-06-23 13:43:14 (台灣)
→
06-23 13:43 TW
懷疑！大爆炸距今１４０億年，而光速是速度極限，那麼怎麼可能是９３０億光年？！！除非有東西跑得比光快，或者空間在大爆炸前就已經存在。
15樓 時間: 2016-06-23 15:35:50 (台灣)
→
06-23 15:35 TW
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