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Before the big bang: something or nothing
03 December 2012 by Marcus Chown
Magazine issue 2893.
AS BIG questions go, it's hard to beat. Has the universe existed forever? Over the years, some of the greatest minds in physics have argued that no matter how far back in time you go, the universe has always been here. Others have argued that the opposite must be true - something must have happened to bring the cosmos into existence. With both sides claiming that observations support their view, until recently an answer seemed as distant as ever.
However, earlier this year, cosmologists Alex Vilenkin and Audrey Mithani claimed to have settled the debate. They have uncovered reasons why the universe cannot have existed forever. Yet what nature grudgingly gives with one hand, it takes back with the other - even though the universe has a beginning, its origins may be lost in the mists of time.
Modern cosmology began in 1916 when Einstein applied his newly formulated theory of gravity, general relativity, to the biggest gravitating mass he could think of: the entire universe. Like Newton, Einstein favoured an unchanging universe - a universe that had existed forever and therefore had no beginning. To achieve this, Einstein realised that the gravity pulling together all the matter in the universe had to be countered by a weird cosmic repulsion of empty space.
Einstein's static universe was unfortunately unstable. As the English physicist Arthur Eddington pointed out, such a universe was balanced on a knife-edge between runaway expansion and runaway contraction. A further blow came in 1929 when American astronomer Edwin Hubble observed that galaxies were flying apart from each other like pieces of cosmic shrapnel. The conclusion was that the universe was expanding.
Yet if the universe was expanding, an unavoidable consequence must be that it had been smaller in the past. Imagine rewinding that expansion back to a time when everything was compressed into the tiniest of volumes. This was the big bang.
The big bang theory that has subsequently developed describes the evolution of the universe from a hot, dense state, but it does not say anything about what brought the universe into existence. That still l eaves crucial questions unanswered - what happened before the big bang and was there really a beginning?
Little wonder, then, that the appeal of the eternal universe became popular, not least because such awkward questions need never be asked. In 1948, Fred Hoyle, Hermann Bondi and Tommy Gold proposed that, as the universe expanded, new matter fountained into existence in the gaps between galaxies and coalesced into new galaxies. According to this steady state picture, the universe looks the same today as it has always done and always will. It has no beginning, it has simply existed forever.
However the steady state theory was scuppered by two observations. The first was the discovery in the 1960s that the distant, and therefore, early universe does not look the same as today's universe. The second was the discovery in 1964 of the cosmic microwave background, the hot afterglow of the big bang fireball. More recently, NASA's WMAP satellite has made detailed measurements of this cosmic background and shown that the big bang happened 13.7 billion years ago.
Flaws in forever
A further blow to the eternal universe came from theory. In the 1960s, Roger Penrose and Stephen Hawking were two young theorists at the University of Cambridge. Their work showed that if you reversed the expansion of the universe, it is impossible to avoid reaching a point known as a singularity, where physical parameters such as density and temperature skyrocket to infinity. Crucially, physics breaks down at a singularity making it impossible to predict what lies on the other side. According to Penrose and Hawking, the big bang must truly be the beginning.
So, story over? Well, no. It turns out that there is a loophole in the singularity theorems of Penrose and Hawking. According to Newton's laws, the gravitational pull of an object depends only on its mass. Einstein's insight showed that the strength of gravity also depends on an object's energy density and, crucially, its pressure. In deriving their powerful theorems, Penrose and Hawking had assumed that the pressure of space is always small and positive. But what if they were wrong? "It is just this possibility that has opened the way to modern cosmological theories in which the big bang is not a beginning at all," says Vilenkin. "Chief among them is inflation."
Inflation, a theory that Vilenkin helped to create, starts with a vacuum in an unusually high energy state and with a negative pressure. Together these give the vacuum repulsive gravity that pushes things apart rather than draws them together. This inflates the vacuum, making it more repulsive, which causes it to inflate even faster.
But the inflationary vacuum is quantum in nature, which makes it unstable. All over it, and at random, bits decay into a normal, everyday vacuum. Imagine the vacuum as a vast ocean of boiling water, with bubbles forming and expanding across its length and breadth. The energy of the inflationary vacuum has to go somewhere and it goes into creating matter and heating it to a ferocious temperature inside each bubble. It goes into creating big bangs. Our universe is inside one such bubble that appeared in a big bang 13.7 billion years ago.
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From issue 2893 of New Scientist magazine, page 32-35.
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read all 43 comments Comments 1 | 2 The Universe Does Have A Unique Beginning
Thu Nov 29 18:01:22 GMT 2012 by Julian Mann
This article does seem to demonstrate the unique nature of Big Bang and that it occurred at a specific point in time. Well in Classical time that is. However it seems likely that there are two forms of time, Forward Time and Backward TIme(See Villata) Therefore BB was the point of origin not only for FIT but also for BIT. This gives us a further clue as to the nature of BB, namely the moment when FIT split from BIT. Thus there does not need to have been a "Prior" moment in either form of time, merely a conjoined form of time. Also FIT/BIT is incredibly useful to explain a number of outstanding issues in physics, inter alia to reconcile Quantum Mechanics to Relattivity.
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Mon Dec 03 17:08:21 GMT 2012 by Julyin!
Mann: "This article does seem to demonstrate the unique nature of Big Bang"
Which article? Not the one above. Read it!
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Mon Dec 03 21:43:23 GMT 2012 by Julian Mann
Julyin, i have read article, but have you? 95% of the article explores all the different scenarios, including fringe ideas such as the Cyclic Universe and the Emergent Universe, in every case it concludes that the universe must have had a finite origin. Only in the last few lines of quite a long article, does it consider Susskind's objections to a finite origin, with the admission that we cannot absolutely prove he is wrong at this stage. However bear in mind that this is only one viewpoint in contrast to Hawking, Penrose,Vilenkin and a host of others who do not agree with him. In other words the article virtually rules out any other scenario but the unique Big Bang, but leaves the door slightly open, just in case
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Tue Dec 04 13:06:40 GMT 2012 by Siegfried Proslmeyr
Actually it leaves the door wide open as all of the beginnings of the universe disgussed are speculations and theories, based on some observations. Just because we can observe the universe expanding does not mean that it must have had an absolute beginning
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The Universe Does Have A Unique Beginning
Tue Dec 04 19:14:07 GMT 2012 by Eric Kvaalen
Well Siegfried, that's what the article is saying.
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The Universe Does Have A Unique Beginning
Wed Dec 05 03:28:37 GMT 2012 by mike b
just a question about bubble universes:
If our universe was formed by inflation inside a sea of quark soup why do we assume it will expand forever? We observe the edge of our bubble as it saw some 13E9 years ago. Perhaps the bubble has started to collapse, racing towards us at the velocity of light or at superluminal speed of a cosmic deflation.
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Wed Dec 05 06:12:16 GMT 2012 by Eric Kvaalen
Mike, the density of the universe has been measured and it's not enough to cause a collapse. In fact, it was discovered 14 years ago that the expansion is accelerating.
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The Universe Does Have A Unique Beginning
Mon Dec 03 21:27:07 GMT 2012 by MarkJB
In the first paragraph Marcus Chown fails to distinguish a difference between the meaning of the words 'universe' and 'cosmos'.
Considering what the aricle is about, it's important to have a word for what came into being with the big bang, or our big bang, and whatever may have existed (and still exists) before and beyond.
I choose to call the big bang a cosmos (an ordered whole) rather than the universe, because universe is supposed to mean everything - and the everything may include infinite other cosmoses in a greater infinite eternal universe (that provides the necessary physical conditions for cosmoses to come into being).
All the evidence points to the big bang/our cosmos having a beginning and reason says it could not have come out of absolutely nothing.
My theory (of a greater infinite universe) provides the initial/eternal background physical conditions and also explains the reasons for the accelerating expansion of the cosmos, dark matter, clumping etc.
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Tue Dec 04 11:38:37 GMT 2012 by Jon
cosmoi has got to be better than cosmoses
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The Universe Does Have A Unique Beginning
Tue Dec 04 01:44:58 GMT 2012 by Jason
***facepalm*** Are you lost, Abu? Please leave the grown-ups to conduct their work in peace. Your single book obviously contains enough information to absolutely explain existence... how big did you say it was?
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Tue Dec 04 01:49:43 GMT 2012 by Michel Couture
Roger Penrose has changed entirely his point of view since then with his new cyclic big bangs.
I totally agree with Susskind.
There is no beginning of movement... or time...
Our universe is a small patch of a larger universe. The big bang began in a black hole (black ring), a particle made of multiple Planck wavelentghs, that reached a breaking point due to a too low curvature as it inflated. There is no black hole evaporation. Hawking-Unruh radiation is the elementary particles themselves. Vacuum is made from energy but it is not!!!
see my theory here: http://www.thenakedscientists.com/forum … ic=34413.0
Remember that the latest conclusions supersede earliest ones. So be patient...
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The Universe Does Have A Unique Beginning
Fri Dec 07 08:54:55 GMT 2012 by Zephir
http://hhttp://aetherwavetheory.blogspot.cz/2009/08/awt-and-cosmological-time-arrow.html
The water surface analogy of space time in AWT explains both the existence of symmetrical time arrow, both the red shift as a product of scattering of light with density fluctuations of vacuum
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In The Beginning [ Time And Space Are Inscrutable ]
Sat Dec 01 23:27:20 GMT 2012 by Russ Otter
http://www.noahi.com
"Time and Space", and possibly some force such as gravity are "Infinite", without a Beginning or End, save our own paltry CMB and the theoretical BB and Inflation that we live within.
In other words "Infinity" has no Alpha nor Omega, never did, never will. In this sense we are clearly all contiguous or analog, whether we are digitized or not, as we are part of the theoretical Big Bang coupled with Inflation, as witnessed by the CMB.
However beyond our own BB, is still "Time and Space", which we conveniently often set aside and ignore, but within that Time and Space that we are expanding into we may have infinite numbers of other CMB's or some related companion of sorts, as within our own CMB we are really but a mere muon, in our BB's scheme of Infinite reality.
In other words: "Everything is Nothing and Nothing is Everything": See Essay @ http://www.otterthink.wordpress.com, with other Essay's that relate to Infinity and Time and Space, along with other heretical tales...! There simply is not an Alpha nor Omega relative to Infinity, only relative to the Finite. That is a reality we will forever pursue to unravel...
This article "In the Beginning" is well done, but again, it may mislead unintentionally that the Universe, is restriceted to our own CMB, but implicityly Infinity is un-circumscribed, forever and a day... It defies explanation, as it must. That is want infinity is - By Simple Definition. As to define "Infinity" with a beginning or an end, would be to make it "Finite." And it is inscrutably not...
Thanks again for the very well done article about our own CMB. Russ
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Sun Dec 02 20:56:22 GMT 2012 by Julian Mann
Russ, to my way of thinking anyone who has to invoke the Infinte universe,multiple Big Bangs etc etc, has no real understanding of what is going on. As far as we know, BB occurred at a finite point of time in the past, and there is no evidence that anything is older than that.
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Mon Dec 03 13:52:12 GMT 2012 by JamesinKS
"As far as we know, BB occurred at a finite point of time in the past, and there is no evidence that anything is older than that." - Julian
Julian, isn't that the point of the article?
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Mon Dec 03 16:19:22 GMT 2012 by Eric Kvaalen
Actually, no. It only says that there must have been a beginning to the universe, but not that it was necessarily our Big Bang.
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Mon Dec 03 17:36:16 GMT 2012 by Markjb
"However, earlier this year, cosmologists Alex Vilenkin and Audrey Mithani claimed to have settled the debate. They have uncovered reasons why the universe cannot have existed forever. Yet what nature grudgingly gives with one hand, it takes back with the other - even though the universe has a beginning, its origins may be lost in the mists of time."
The article doesn't expand on their reasons for thinking there must have been a beginning to the universe, but whatever, there is no reasoning that will ever be capable of changing the fact that, in terms of physics, you cannot get something out of nothing.
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Mon Dec 03 17:03:34 GMT 2012 by MadScientist72
"As far as we know, BB occurred at a finite point of time in the past, and there is no evidence that anything is older than that."
A simple explanation for that would be that anything older in the vicinity of "our universe" was displaced by the inflationary bubble of our BB and is currently surfing the outer surface of that bubble, where we can't see it.
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Mon Dec 03 17:19:31 GMT 2012 by MissChief
Since there is no explanation for dark matter in the standard model, how do we know that dark matter is not the matter from other (older) cosmoses? There is no reason to suppose that 'inflation' would dispalce that matter if it were there.
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Mon Dec 03 22:37:53 GMT 2012 by rotorhead1871
its not in our domain to know any universe other than that created by the effect we call the BB. it is intuitive and provable...that the universe is much more than what the BB created...in universe terms the BB was a local expansion, 13-14B years ago...we will be able to see beyond that..and there will be something there.
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In The Beginning [ Time And Space Are Inscrutable ]
Mon Dec 03 20:21:18 GMT 2012 by citicrab
A word combination "nothing existed" is logically incorrect. It may have some well-defined mathematical meaning that our everyday language is unable to relay.
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Mon Dec 03 22:23:35 GMT 2012 by Russ Otter
http://www.noahi.com
Dear Everyone that commented about my rhetoric regarding [Time and Space Being Inscrutable],
Actually I do respectfully really thank you all for responding to a normal sore spot for our finite grey-matter...: "That Infinity is beyond our grasp."
It has been clear and obvious to me for a life time, that we are confined within the un-confinable. That to distinguish our own BB as all that ever was or ever will be, is myopic and respectfuly naive. I say respectfully because the grey-matter we have cannot and will not compute Infinity. So we conveniently ignore its truth, so that our thought process will not implode in our brains! And believe me to really try to understand infinity would possibly cause one to go insane. Yet we will forever try as we must pursue knowledge. This I believe.
But Infinity beyond our scope of knowledge is a reality - that is sacrosanct. Believe as you wil, but please read some of my essay's about this subject if you continue to doubt. @ http://www.otterthink.wordpress.com. You may forever doubt, and believe that our BB is all that ever was or will be, and so be it. But I have a couple of questions for you: What is the space surrounding our CMB? Where did it come from and when did it begin?
The truth is omnipotent (INFINITE), and not subject to finite mind-thinking... Always will be - and always has been. Infinity is the absolute conundrum that gives us our finite world and life.
I am an agnostic, but there is an old wise verse from Exodus in the Judeo-Christian Bible: "You cannot see God and Live." In secular translation: You are Finite and you will not see what is Omnipotent or Infinite, and still be alive or Finite. That twain shall not meet. Hence there is more to us than our own CMB.
Science is an infinite journey and a quest that will improve communication with time, and therefore improve our world! You all are on that journey. I hope you the best.
Thank you all again for responding so thoughfully or poignantly...
Russ
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Tue Dec 04 10:53:09 GMT 2012 by MarkJB
Russ, Eric and all
I agree with the view that the universe (beyond the big bang) is infinte and thus ultimately mysterious and unfathomable.
However I think every idea of the nature of the universe should have some physical effect and thus evidence to go with it. Then in 1994 I reasoned that, in terms of gravity and conservation of momentum, if there were an infinite universe (of infinite other cosmoses) beyond/outside of our big bang then the physical effect /evidence would be that the cosmos was accelerating apart. This theory also gives an explanation for the dark matter phenomenon, advanced clumping, homogeneity and other observations (see my comment below the "variable dark energy" article in NS last year)
Four years later my theory was affirmed by observations.
There is a certain mathematical approach, used by Newton, that says an infinite surrounding universe would not cause, directly or indirectly, our cosmos to accelerate apart - and that may be the main sticking point for some. However, that mathematical approach may be mistaken , as I explain now ....
If you think of a particle inside a hollow spherical shell, then the overall vector of force from the shell to the particle is zero, wherever the particle is....(a particle on one side of the cavity in the shell may be nearer to the mass of the shell on that side but then have more of the mass of the shell on it's other side, such that the sum of all the vectors cancel each other out) Likewise the overall vector of force from the particle to the shell would not pull the shell in any direction (but that doesn't mean it is not pulling on the shell to contract (and thus, by conservation of momentum, itself to expand).
Then in Newton's reasoning you add further outer shells, ad infinitum (radiating concentrically from the centre of the first shell) which have the same effect, ad infinitum, to say the same applies to an infinite universe.
The error in this reasoning is that when you are using the idea of a shell and more shells, you are not modelling an infinite universe but always a finite universe (that is infinitely big). Crucially your concentric circles/shells share a particular centre...and that does not apply to an infinite universe.
Forget the shells and consider the object as being somewhere inside a spherical cavity/ bubble in an infinite universe. Now consider that the singular object only has a finite pulling power (on the surrounding infinity - unlike the infinite pulling power of the collective objects of the surrounding infinity on the object - which cancels itself out as a vector on the object).
With a finite pulling power the object has in effect a finite range, or diminishing range of effective pull, on the objects that surround it (especially where action is quantized as in post-Newtonian quantum physics). If you give that range a finite radius (from the object of course) then you have a different scenario. Now when the object is to one side of the cavity, say the left side, there is more mass within its radius of range to it's left than to it's right. where there is a bigger empty volume of mass. In this description then, you do have a stronger vector of pull from the object to collective objects on the side of the cavity that it is nearest to, meaning that overall, objects within the cavity will have a tendency to separate and be 'pulling themselves apart'.
What may stop them separating is the gravitational force between the objects, but if that is countered/ neutralised by rotations then the system has a background tendency to expand / pull itself apart.
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Tue Dec 04 19:20:33 GMT 2012 by Eric Kvaalen
Mark, it doesn't work that way. You can't ignore the mass outside a certain distance from the object on the basis that its gravitational pull is too weak.
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In The Beginning [ Time And Space Are Inscrutable ]
Wed Dec 05 09:29:11 GMT 2012 by Markjb
Eric, I don't ignore the mass of the surrounding infinity on the basis that it's pull is too weak. Quite the opposite if you follow my theory!
Maybe I should add that there are two ways of simply calculating the acceleration due to gravity between two objects. One is to work out a singular acceleration based on the sum of their two masses (and the distance apart). The other is to work each acceleration pull separately and then add them together. I think the second way is more appropriate given that they are separate objects and it gives each one an acceleration that agrees with the conservation of momentum between them.
Mathematically the resultant acceleration is the same.,,,
except if one object is an infinite surrounding universe and the other object is just a singular object within it, then the defined single acceleration vector between them is infinite and omni directional and cancels itself out - so there is no effect. But if the acceleration is defined as two then only the pull from the surrounding infinity on the object is annihilated, whilst the pull of the object on the surrounding infinity of things is finite and effective. And to what extent that object/cosmos pulls things in it must be moving out/expanding to agree with the conservation of momentum.
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Universe And Its Apparent Beginning
Mon Dec 03 18:22:52 GMT 2012 by Acorn Ayton
Going with the observed expansion of the universe, and the apparent conclusion of the singularity as a beginning 'point' of expansion starting, one surely must wonder how the conditions were manifest such that the above singularity could exist. Are we to throw out cause and effect partnership? If not, what caused/permitted a singularity to exist?
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Mon Dec 03 22:30:03 GMT 2012 by Julian Mann
Jolly good questions, Acorn. Let me plant the seeds of a few ideas in your mind. Let us suppose for a moment that Time has not one direction, but two, but the both forms of time started out at Big Bang. (There are now quite a number of arXiv papers on Backward Causality, a concept initiated by Aharanov, and a similar idea, Forward in Time and Backward in Time proposed by Villata) In my view Dark Matter is probably antimatter which is subject to Backward Time(Hence we cannot see it) i.e. Antimatter was not destroyed at Big Bang.
Now we can re-run the universe(both the Matter part and the Dark Matter part) back/forward to Big Bang, At this juncture we now have a singularity with what must have been a conjoined form of time. The splitting of Time, into two was what gave rise to Big Bang and Inflation. Thus your question on cause and effect has been answered. Cause and Effect as we understand it was only created from the time that Classical Time?Backward Time came into existence. Also Relativity and QM only come into play from the Singularity onwards. It is also my view that QM runs according to Backward Time and not the Classical Time of Relativity.
Therefore I could turn your question around into what caused Time to split into two, and give rise to causality in the first place?
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Tue Dec 04 05:54:14 GMT 2012 by jaffray geddes
Why all this speculation on time? This urgency to find a'beginning'! Time does not exist and never has. Time is a man-made manufacture, the whole gigantic question is reduced to a word game of man casing his tail and people called scientists coming up with speculations resulting
in people like you and me coming up with more
futile speculations, it is a meaningless pursuit.
Accept the day as it presents do no follow the stars or the moon shine by night, and when light breaks celebrate by throwing flowers....
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Tue Dec 04 10:26:15 GMT 2012 by Alfred Maddenstein
Those people need to learn the basics. Time is a human abstraction of motion. That is all which this relative measurement ultimately resolves to. It resolves with no residue. Attributing to the relative motion of objects a single fixed universal direction is a gross fallacy which is the only foundation all these endless speculations are based upon.
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Universe And Its Apparent Beginning
Mon Dec 03 22:37:42 GMT 2012 by Julian Mann
By the way Susskind started life as a plumber. In my view he should have stuck with that career!
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Universe And Its Apparent Beginning
Tue Dec 04 11:12:04 GMT 2012 by Markjb
In my view that makes him more credible. Some manual engagement with practical reality /real physical things is probabaly the best preparation for someone who wants to understand and have sound ideas the universe.
As for the so called experts and specialists in a field, there is a view (in this week's issue) that their ideas are not only useless but unhelpful.
See (long URL - click here)
I'm happy to say that I'm not an expert in the field of cosmology (since no such person exists) , though I do have the theory that best explains the accelerating expansion of the cosmos etc.
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Tue Dec 04 19:28:39 GMT 2012 by Eric Kvaalen
Someone (I don't remember his name) wrote a short humorous reply about how he once had a big bang in his bathroom and needed a plumber.
In what way did that breach the terms of use?
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Tue Dec 04 21:49:38 GMT 2012 by Julian Mann
I agree with you Eric, and it is very funny too. That is not the only problem with the current style of NS, it has become quite a drab,boring read since the previous Editor left. Can we have him back please? Come on, please inject some excitement into NS, some contoversy, as in Creationists take on the Evolutionists. Also some humour would not be out of place either.
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