A Fundamental Understanding

WMAP image of the CBM

WMAP image of the CMB

by GENE HOWINGTON

“I am large, I contain multitudes.” – Walt Whitman

Our understanding of the universe changed in a fundamental and exciting way this week when the results of the BICEP2 experiment were revealed. It all revolves around something known as B-mode polarization, a signal in the cosmic microwave background radiation.  The CMB is the thermal radiation assumed to be left over from the “Big Bang” of cosmology. These signals are important because they reveal information about the state of the universe before it was directly visually observable. One must keep in mind that astronomy is a kind of time machine and that when we observe the universe we are looking back in time. In “Watchmen”, the character Doctor Manhattan notes that “All we ever see of stars is their old photographs.” The truly staggering physical scale of the universe combined with the speed of light is what makes this so. The universe is so large, it actually takes about eight minutes for the light from the sun to reach Earth. But if optical observations of the oldest stars and galaxies is analogous to “baby pictures” of the universe, then observing the cosmic background radiation is like looking at an ultrasound. However, the results of BICEP2 pull information out of that background radiation that is probably more analogous to a pregnancy test, revealing information about the very first infinitesimally tiny moments of creation when the universe was far less than one-trillionth of a second old.

Alan Guth

Alan Guth

It tells us, if confirmed, that the inflation model of cosmology proposed in 1980 by physicists Alan Guth and Andrei Linde is right. BICEP2 detected patterns, a gravitational wave, of polarization in the CMB that are a direct result of quantum gravitational fluctuations that occur even in vacuum. This not only illustrates quantum fluctuation and confirms predictions made by the inflation model of the early universe, it also has other implications. Implications that I find truly wondrous and awesome – in the original meaning of that word – and far more substantial than the (at least one) Nobel Prize this fundamental discovery will lead to.

Implications philosophical, sublime and profound.

Why is this important? Aside from the fact that the news of the discovery seems to make Professor Linde and his wife Renata very happy?

For one thing, it explains how we ended up with a universe that is isotropic (it looks the same in every direction, whomever you are, wherever you are) and the relative uniformity of the CMB.  The WMAP image of the CMB at the head of the column is colorful, but those colors are falsely highlighted to show what are actually miniscule variations in the temperature of the CMB. The difference between “red” and “blue” is so small, cosmologists consider the WMAP data as showing a “smooth” or homogeneous universe. Although having an isotropic and homogenous universe is the modern terminology embedded in the Cosmological Principle, it is an idea that can be traced all the way back to Newton’s seminal 1687 work the Principia Mathematica. To put it another way, everyone knows that every explosion they’ve ever seen is messy and disordered so that raises the question why isn’t the universe?  It is ordered at a sufficiently large scale and physics works the same everywhere. These wave patterns detected in the BICEP2 experiment were not only predicted by the inflation model, but represent evidence of the quantum mechanisms responsible for both isotropy and homogeneity we see in the modern observable universe.

In itself, that is a pretty damn exciting discovery. We know why the Big Bang resulted in order instead of chaos; an oscillation in the quantum fluctuations present at the very start of the Big Bang expansion.  But this raises the question of where did the huge amount of energy required to generate this wave pattern come from?  Why is that important?  We’ll get to that via a brief detour to my 13th summer on this planet.

Like most 13-year old boys, I was curious about girls to be sure.  And literally everything else too. I was born curious and inquisitive. It is simply my nature and why I maintain such a broad area of interests to this very day. Some things I’ll even say I’ve figured out.  Girls aren’t one of them.  But I digress from my digression. When I was 13, I was really interested in quantum mechanics. I had previously found classical physics very interesting and structured.  Orderly.  F=ma. N=mg. Things I saw could be measured, tested, understood. That led to learning about particle physics. The allure of order at sliding scales was very appealing.  E = mc2.  Energy and mass the same thing?  Wow!  Space and time all really part of a connect whole in spacetime but each still a bit of a mystery?  Joy! Consequently, that led to the learning about the strange and often counter-intuitive world of quantum mechanics.  Why were particles there and not there? Why all the empty space at the atomic level? Why all the randomness? How did such weirdness underpin all of such an orderly reality? So many questions.

It was the intellectual equivalent of sudden onset cocaine addiction, love at first sight, the best meal possible, a Mozart concerto, driving a Ferrari and falling off a cliff all rolled up into one.

I read everything I could lay my hands on and while some of the more esoteric maths were beyond my grasp at that age (some still are), the pictures they painted via the authors explaining them didn’t escape me. At the time, there was one major school of thought on how to interpret the strangeness of quantum mechanics: the Copenhagen interpretation favored by physicist Niels Bohr, Werner Heisenberg and many other physics greats since the 1930’s. It is still widely accepted today.

It has problems though. The Copenhagen interpretation didn’t sit well with me. I soon found out that it didn’t sit well with others including many physics professionals. Even Einstein thought is was wonky and it was his work that led directly to the formulation of quantum mechanics. What kind of problems? These problems are best understood by the famous Schrödinger’s Cat thought experiment and thinking about in the context of a critical feature of the Copenhagen interpretation: the collapse of the wavefunction. The doubts of others about the Copenhagen explanation of this phenomena between observer and observed quantified what didn’t set well with me and we’ll get to that, but first, let’s look at that famous cat, the collapse of the wavefunction and another way to deal with the collapse of the wavefunction that is wildly different than the Copenhagen version.

Schrödinger’s Cat is a thought experiment created by Erwin Schrödinger as a way to think about quantum entanglement. Using an example in reductio ad absurdum, Schrödinger concocted an experiment to illustrate how the Copenhagen interpretation deals with paradoxes created by the probabilities inherent when pairs or groups of particles are generated or interact in ways such that the quantum state of each particle cannot be described independently.  Instead a quantum state may be given for the system as a whole.  He did this by describing a cat in a box whose life or death was dependent upon the decay of a radioactive isotope. As described by the man himself:

One can even set up quite ridiculous cases. A cat is penned up in a steel chamber, along with the following device (which must be secured against direct interference by the cat): in a Geiger counter, there is a tiny bit of radioactive substance, so small, that perhaps in the course of the hour one of the atoms decays, but also, with equal probability, perhaps none; if it happens, the counter tube discharges and through a relay releases a hammer that shatters a small flask of hydrocyanic acid. If one has left this entire system to itself for an hour, one would say that the cat still lives if meanwhile no atom has decayed. The psi-function of the entire system would express this by having in it the living and dead cat (pardon the expression) mixed or smeared out in equal parts.

It is typical of these cases that an indeterminacy originally restricted to the atomic domain becomes transformed into macroscopic indeterminacy, which can then be resolved by direct observation. That prevents us from so naively accepting as valid a “blurred model” for representing reality. In itself, it would not embody anything unclear or contradictory. There is a difference between a shaky or out-of-focus photograph and a snapshot of clouds and fog banks.” — Erwin Schrödinger, Die gegenwärtige Situation in der Quantenmechanik

So the indeterminacy of the system (all its possible outcomes) are resolved when the event is observed and the wavefunction collapses to a single “point of reality”. The cat is both alive and dead – a paradox – until it is observed. It is a way to deal with the uncertainty in the system, but it nagged at me when I read about it.  So I read some more.  I found out that physicists had some issues with that result as well.  When I read their chief criticism, I had one of those moments where one has been pummeled by the obvious missed.  I believe at the time I may have even said words to the effect of “Well . . . duh.” The problem with this is that this explanation isn’t treating the observer as part of the greater set of quantum probabilities that is the entire universe.  They are rooted in the classical world. But still the question remains: how to reconcile the paradox of the probable and the observed?

Hugh Everett

Hugh Everett

That is when I found out about Hugh Everett. He had a totally different idea on how to explain the collapse of the wavefunction. He called it the Theory of Universal Wavefunction. It later came to be known as the Many-worlds interpretation of quantum mechanics. As described by Everett’s introduction to his 1956 thesis paper The Theory of the Universal Wave Function, “Since the universal validity of the state function description is asserted, one can regard the state functions themselves as the fundamental entities, and one can even consider the state function of the entire universe. In this sense this theory can be called the theory of the ‘universal wave function,’ since all of physics is presumed to follow from this function alone.” In other words, all of objective reality is a single wavefunction and all other observable wavefunctions and their subsequent outcomes are a subset of this universal wavefunction. This not only addressed the flaw in the Copenhagen interpretation as illustrated by Schrödinger’s Cat, it has a really interesting consequence for understanding the apparent collapse of wavefunctions. The observation is a subjective event. In Many-worlds, this subjective appearance of collapse of the wavefunction is explained by quantum decoherence. I was thinking of a tidy way to summarize quantum decoherence, but the summary at Wikipedia is really quite good:

Decoherence does not generate actual wave function collapse. It only provides an explanation for the observance of wave function collapse, as the quantum nature of the system ‘leaks’ into the environment. That is, components of the wavefunction are decoupled from a coherent system, and acquire phases from their immediate surroundings. A total superposition of the global or universal wavefunction still exists (and remains coherent at the global level), but its ultimate fate remains an interpretational issue. Specifically, decoherence does not attempt to explain the measurement problem. Rather, decoherence provides an explanation for the transition of the system to a mixture of states that seem to correspond to those states observers perceive. Moreover, our observation tells us that this mixture looks like a proper quantum ensemble in a measurement situation, as we observe that measurements lead to the ‘realization’ of precisely one state in the ‘ensemble’.”

Paradox resolved, wavefunctions don’t really collapse and observation becomes a moot point. Everything that can happen, does happen. Just not in the same universe.

What an intriguing idea. At a philosophical level, I also find that proposition strangely comforting. It is no secret I am not a religious person, but when I first read about Everett’s work, I was still exploring the idea of God quite actively. To me, the notion of an all powerful being was limited by a single universe with one set of outcomes.  Wouldn’t an omnipotent and omnipresent being unfettered by the rules of any physics be interested in everything possible? I know if I were a god, I’d want a multiverse instead of a universe to play with.

That is what I find so interesting about the BICEP2 discovery.  It is not only the first evidence of Hawking radiation (the gravitational wave proper are a result of the same kind of quantum fluctuation Hawking previously described happening around the event horizons of black holes), the first experimental evidence of quantum gravity, and confirmation of the inflation theory, but almost all versions of inflation theory require the Many-worlds interpretation.  As Andrei Linde himself notes “In most of the models of inflation, if inflation is there, then the multiverse is there. It’s possible to invent models of inflation that do not allow [a] multiverse, but it’s difficult. Every experiment that brings better credence to inflationary theory brings us much closer to hints that the multiverse is real.”  This is also good for another physics theory for which I am a proponent: M-theory. Where did the huge amount of energy required to generate this wave pattern come from? The high energies required to generate this gravitational wave at the start of the Big Bang are best explained by the M-theory version of the Big Bang where a universe is “kicked off” by the collision of “dimensional membranes” that not only result in multiverses, but cyclical multiverses.

Not only does everything that can happen, happen, everything has happened before and will happen again.

If I were a god and I wanted a cosmic playset?  A cyclical infinite multiverse would make me think of the title of a great short story by Brian Aldiss: “Supertoys Last All Summer Long”.

Somewhere, you are everything you ever and never wanted to be.

How exciting is that?

And last, but certainly not least, congratulations Professors Guth and Linde. This not only goes a long way to confirming your theory, but I am confident that it will be remembered by the history of science (at least in this universe) as one of the greatest discoveries in the history of humanity.  Good show, gents.

Creation just got a little more wondrous.

What do you think?

Source(s): bicepkeck.org, Huffington Post (1, 2, 3), Wikipedia (various references)

About Gene Howington

I write and do other stuff.
This entry was posted in Astronomy/Astrophysics, Cosmology, Physics, Quantum Mechanics, Science. Bookmark the permalink.

20 Responses to A Fundamental Understanding

  1. po says:

    Pretty interesting write up, Gene. I am smiling at your excitement, as it is so palpable! Listening to scientists talk about science reminds me of my spiritual guide’s saying that at the greatest range of his science, the scientist becomes a mystic, and at the highest range of his mysticism, the mystic becomes a scientist, for they both operates at the highest ranges of knowledge and intuition, both fraternal twins.
    Not to want to revisit a previous discussion, and not to want to keep hammering this dead horse (to mix my metaphors), but speaking from a religious perspective (since I am not qualified to speak from the scientific one),reading your piece felt no different than reading my Sufi forefathers.
    When you say “To me, the notion of an all powerful being was limited by a single universe with one set of outcomes. Wouldn’t an omnipotent and omnipresent being unfettered by the rules of any physics be interested in everything possible? I know if I were a god, I’d want a multiverse instead of a universe to play with.”, I think of the quranic quote that says “…Lord of ALL the worlds”, which joins the Hindu and old traditions ‘belief in other realms/universes, and in reincarnation.
    There is also a quote from Prophet Muhamad in which he mentions other Adams before this Adam, as if creation has happened previously or concurrently with ours. According to the Companion Abu Saeed Al-Khudri, Allah has created forty thousand worlds, and the earth and all the creatures on it are only one of those worlds. (Tafsir Ibn Kathheer, quoted by Dr. Hosny Hemdan Hamama in Are There Other Universes?)
    Yes indeed, creation just got a little more wondrous.

  2. I am still trying to digest this new information. Thanks for this. As soon as I can come up for air on this end, I will read it more carefully. I love this stuff. As Po says above, “Yes indeed, creation just got a little more wondrous.”

    Not only more wondrous, a little more weird as well.
    Is fhearr na ‘nt-or sgeul innse air choir. (That is Scots Gaelic, meaning, better than gold is a tale rightly told.)

  3. rb137 says:

    The deep paradox in the Copenhagen Interpretation happens when it crashes into Special Relativity (SR). From SR, we have issues of simultaneity: If two observers in two different intertial reference frames observe a series of events they will disagree on the order with which the events occurred. It’s a consequence of having space and time tangled together. This causes issues with quantum entanglement.

    In quantum entanglement, two objects are entangled by a law of physics — for example, a conservation law. If one particle decays into two daughter particles, the spins for the two daughter particles have to add up to the total spin for the mother particle. Also, because the two daughter particles share a wavefunction, this effect is non-local. One daughter could travel to Jupiter, and another could travel to Neptune, but they still are bound by conservation of spin — that is until someone measures one of them.

    If the mother particle’s spin is 0, and you measure daughter 1’s particle as spin -1/2, the other daughter particle’s spin must be +1/2. Suppose you (and one daughter) is near Neptune, and I (and the other daughter) are near Jupiter — and we have some agreement that we’re going to try and measure them at the same time. By Special Relativity, we can’t resolve who measured the particle first.

    If we can’t resolve who measured the particle first, we can’t resolve who collapsed the wavefunction. You think you collapsed the wavefunction, and I think I did. This breaks the Copenhagen Interpretation completely. However…

    According to the scientific method, we construct a theory, and if it disagrees with experiment we discard it. The problem is that we can’t construct an experiment that disagrees with the Copenhagen Interpretation. (See Bell’s Theorem, and related experiments.) It is the most successful scientific theory we’ve ever constructed (and that’s not really hyperbole.)

    The Many Worlds Interpretation of Quantum Mechanics works out this paradox (as well as gives us wiggle room about the fact that we really don’t understand Dark Enegy very well, and makes certain dire issues in the mathematics less problematic.) Problem is, we can’t measure anything in any of those other universes — so what we’ve done here isn’t entirely scientific.

    So — the real question is: Does our discontent matter? Must the universe reveal itself in a way that’s free of paradoxes, or is this expectation just an artifact of the way we think and the tools we’ve made? Or, if our discontent does matter, is it okay to return to having a partially philosophical cosmology?

    In any case, we won’t solve those questions today. But this discovery of gravity wave signatures in the cosmic microwave background is an enormous boost to the brilliant people who spend their days thinking about inflation and its consequences. My very best to Linde and Guth, among a zillion others that made this understanding possible.

  4. rb137 says:

    I should also say — if you think very long, you’ll convince yourself that you are the only person in the universe who can collapse a wavefunction, or nobody can.

  5. Tony C. says:

    I think the problem with the many worlds theory is it leads to a paradox of infinite infinities and infinite energies. I’ve now got two Schrodinger cats; but wait: In that one hour, at how many time points could the isotope have decayed? Isn’t that an infinite number of points? Doesn’t that mean I have an infinite number of futures, and an infinite mass of live cats and dead cats?

    Or does it still rely on the observer, just indirectly — That only when I open the box does the universe split in two? So now we have two cats, but instead of the wavefunction collapse depending on the action of an observer, the split of the universe depends on the action of an observer, and the observer remains central to reality.

    The same thing happens to photons; they are absorbed or reflected. But actually, both! How does the universe split in two every time a photon encounters some field? I understand we can represent some such things as wavefunctions, I don’t understand what it means for all of reality to really BE a wavefunction with every possible outcome, or for the splits to still be observer centric.

    I subscribe to the Penrose interpretation. It is a testable hypothesis. He suggests that there is possibly some limit to the amount of mass, perhaps on the order of a Planck mass, (which is hefty) that can be involved in a quantum superposition, and when the mass of the entangled particles reaches that limit the wavefunction collapses spontaneously. He has proposed detailed experiments to test that hypothesis.

    But it would make more sense. We think “observers” are necessary but they are not; we (and our equipment) are just massive enough to always force a wavefunction collapse. Distance would not matter; just as it does not matter now to quantum entanglement. But total involvement would have a limit.

  6. Tony,

    The universal wavefunction is objective. Observers aren’t necessary under MWI either. They are convenient in compiling what we consider our body of knowledge but they are not required. A tree that falls in the forest still makes a sound whether or not anyone is around to hear it.

  7. rb137 says:

    “The Many Worlds Interpretation of Quantum Mechanics works out this paradox (as well as gives us wiggle room about the fact that we really don’t understand Dark Enegy very well, and makes certain dire issues in the mathematics less problematic.) Problem is, we can’t measure anything in any of those other universes — so what we’ve done here isn’t entirely scientific.”

    To which I reply, “The Incompleteness Theorem(s) and a maximally large set.”

    “So — the real question is: Does our discontent matter?”

    No.

    “Must the universe reveal itself in a way that’s free of paradoxes, or is this expectation just an artifact of the way we think and the tools we’ve made?”

    No. And I think that you’ve missed that infinities are a form of paradox (along with self-reference, vicious circularity and contradiction). The suggested solution here leads to an answer that is not testable for consistency within the system itself (Gödel) and yields a specific type of paradox (infinities) at sufficient scale (the multiverse and what Tony rebels against). A dialetheia. Since I accept the mathematics underlying the Incompleteness Theorem(s) as valid (and have an extensive background in Western as well as Eastern philosophy where such paradoxes are better tolerated/accepted than in the West), this presents little problem for me. I accept our individual and species understanding of the universe/multiverse are always going to be 1) imperfect and 2) less than whole.

    “Or, if our discontent does matter, is it okay to return to having a partially philosophical cosmology?”

    There is nothing here to suggest that a philosophical and scientific view of cosmology are mutually exclusive. In fact, I have both and have had both for some time. I would think most people seriously minded about science do, especially those interested in cosmology. Even atheist scientists as atheism is a lack of religion, not a lack of philosophy, operational or otherwise.

  8. rb137 says, “I should also say — if you think very long, you’ll convince yourself that you are the only person in the universe who can collapse a wavefunction, or nobody can.”

    Not really. Under MWI, wavefunction collapse doesn’t really happen at the universal level as all possible outcomes occur. Observation is subjective and what happens (or appears to have happened) is not dependent upon observation, ergo the observer is more irrelevant than not. In that way, reality is a state of mind (a phrase coincidentally enough I got sent to the office for writing repeatedly on the 3rd grade reading room walls). That, however, is a topic for a different kind of column altogether.

  9. rb137 says:

    Whatever you say…

  10. What I say is why don’t you contact Profs Linde and Guth and the BICEP2 team and tell them what they’ve done “isn’t entirely scientific”. Better yet, find some evidence to contradict their findings. If the implications of the science on a philosophical level don’t make you happy? Good news. Your happiness is not required and just as subjective as observation under a decoherence/universal wavefunction framework. Just so, as your happiness is not required, neither is your agreement.

  11. Tony C. says:

    Gene: FYI, some more info, the following is a comment by Prof. Robert H. Brandenberger, a theoretical cosmologist and a professor of physics at McGill University in Montreal, Quebec. The link goes to his comment on a story in Quanta about BICEP. It reads:

    “If confirmed, the BICEP results provide a brilliant discovery of primordial gravitational waves. On the other hand, this is NOT a confirmation of inflationary cosmology. There are other sources of primordial gravitational waves. In fact, some alternatives to inflationary cosmology also produce primordial gravitational waves. The slope of the spectrum of waves reported by BICEP appears, in fact, to be in disagreement with the predictions of inflationary cosmology, and rather confirms the prediction of a “blue tilt” which was first made by “String Gas Cosmology”, an alternative to inflation which is based on superstring theory.”

  12. Tony C. says:

    Gene: Neil Turok is also skeptical; certain aspects of the BICEP data may actually speak against inflation.

  13. Tony,

    Time will tell, but I did qualify this column by an “if confirmed”. I think that allows not only for future proof to confirm inflation but to reach other conclusions as well. I will stipulate though that I’m rooting for Team Inflation.

  14. Tony C. says:

    Oh I know you qualified. I’m rooting for a cyclical version; myself, and BICEP is being presented as a setback for that route. So I was reading for critical comments from actual cosmological physicists. (Since I don’t know enough to argue the case on my own!)

  15. Tony,

    The cyclic version isn’t dead I don’t think. Reading between the lines of Max Tegmark’s reactions and directly from Michio Kaku’s reaction, the M-theory based cyclic version seems to be still in contention. But there is still a lot more reading for me to do than I actually have time for at the moment. Which is pretty much always the case with me. 😀 So many books, so little time.

  16. Tony C. says:

    Gene: ??? Max Tegmark says: Today is also disappointing for the ekpyrotic/cyclic models that had emerged as the most popular alternative to inflation: they are ruled out by BICEP2’s gravitational wave detection.

    What did Kaku have to say?

  17. Hmmm. I did read that, but apparently it didn’t register (I’ve still got a plate full o’ hot mess I’m dealing with here so I’m not on my A game). It is my understanding of the ekpryotic model that the brane collision is still a super small intersection at atomic scales and inflation would be an after-effect of said collision (I may be wrong, I’m a bit behind in reading physics in general). The real difference being the precursor of expansion as a singularity versus a brane intersection. However, it is my understanding that the ekpyrotic models are not the only cyclical models and that both cyclical and inflation models can work under the Big Bang Lambda-CDM model and are not inherently mutually exclusive. Kaku said, “”If it banged once, why can’t it bang again? It opens up a can of worms. Inflation theory is like a Trojan horse. It opens the door to many bangs and many universes. That’s the nature of quantum theory.” I’d kinda like to hear why Tegmark thinks the ekpryotic model is out in greater detail.

  18. Tony C. says:

    Gene: I’m not sure. As I understood Hawkings bounce model, there is one universe that expands and then collapses. Because of quantum uncertainty, neither black holes nor the universe can collapse to an infinitely small point (especially if gravity is quantized too). So what happens instead is all matter packs into an atomic scale volume; that (for some reason) causes gravity to invert and rebound in inflation.

    I guess that model should still be alive, the BICEP data show the energy of inflation at the same energy it takes to merge the Strong force, electromagnetic, and Weak force (under super-symmetry, which we know the LHC is killing).

    So there will be investigations of how that phase change might be related to inflation; which could provide the missing muscle for Hawking’s bouncing universe idea.

  19. Tony C. says:

    BTW, and off-topic, another interesting article at Quanta, on the physics behind the origin of life.

  20. Blouse says:

    When I first read the news I knew someone would tackle it on the blog. Damn! I’m on vacation so don’t have the time right now but this so interesting that at least have to take the time to read

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