Of Particular Significance

How Evidence for Cosmic Inflation Was Reduced to Dust

POSTED BY Matt Strassler

POSTED BY Matt Strassler

ON 02/06/2015

Many of you will have read in the last week that unfortunately (though to no one’s surprise after seeing the data from the Planck satellite in the last few months) the BICEP2 experiment’s claim of a discovery of gravitational waves from cosmic inflation has blown away in the interstellar wind. [For my previous posts on BICEP2, including a great deal of background information, click here.] The BICEP2 scientists and the Planck satellite scientists have worked together to come to this conclusion, and written a joint paper on the subject.  Their conclusion is that the potentially exciting effect that BICEP2 observed (“B-mode polarization of the cosmic microwave background on large scales”; these terms are explained here) was due, completely or in large part, to polarized dust in our galaxy (the Milky Way). The story of how they came to this conclusion is interesting, and my goal today is to explain it to non-experts.  Click here to read more.

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71 Responses

  1. Matt,

    One question I have is if this new information has indeed undermined all of the theories of eternal inflation, which seemed to be implied by a post over at the Starts with a Bang blog (https://medium.com/starts-with-a-bang/ask-ethan-74-gravitational-waves-c21e701f9bde).

    If that were true I would think it would be pretty big news considering the prominent cosmologists who have been proposing it over the years. Your thoughts would be greatly appreciated.

  2. The above analysis of avian reception presents a pic-
    ture of an array of quantum meters located in the retina
    of the bird, each of which measures the magnitude and
    orientation of the magnetic field relative to its own ori-
    entation and produces a classical signal in the form of a
    chemical population derived from the integrated time de-
    pendence of the protonated radical pair population. One
    of the underlying assumptions in radical-pair-based mag-
    netoreception is that the bird’s brain undertakes process-
    ing and integration of all such classical signals deriving
    from an array of quantum meters]: it thus generates
    visual modulation patterns via chemical signaling of the
    intrinsically quantum protonated state yield. It is these
    variations in the modulation patterns that yield the de-
    sired magnetic field information ]. An interesting as-
    pect of this biological quantum measurement is that it
    is continuous in time, with the cumulative protonated-
    state population providing the calibration for the classi-
    cal field.

    1. The above analysis of avian reception presents a pic-
      ture of an array of quantum meters located in the retina
      of the bird, each of which measures the magnitude and
      orientation of the magnetic field relative to its own ori-
      entation and produces a classical signal in the form of a
      chemical population derived from the integrated time de-
      pendence of the protonated radical pair population.
      SO IT HAS A SUB-ATOMIC QUANTUM COMPASS?
      One of the underlying assumptions in radical-pair-based mag-
      neto reception is that the bird’s brain undertakes process-
      ing and integration of all such classical signals deriving
      from an array of quantum meters]: it thus generates
      visual modulation patterns via chemical signaling of the
      intrinsically quantum protonated state yield.It is these variations in the modulation patterns that yield the de-sired magnetic field information ].
      THE BRAIN OF THE BIRD PROCESSES THE SIGNALS AND THANKS
      TO A NUMBER OF QUANTUM EVENTS IT GETS A VISUAL MAP?
      An interesting aspect of this biological quantum measurement is that it
      is continuous in time, with the cumulative protonated-
      state population providing the calibration for the classi-
      cal field.
      THE PROCESS IS SPONTANEOUS?

      Is that what you are saying Margot?

  3. A large class of chemical reactions or biological processes may be described as a quan- tum measurement where the biological complex of interest assumes the role of a quantum meter
    *************************************************************************************
    Even though a quantum measurement is normally per-
    ceived as interfacing a system with a classical apparatus,
    it is convenient to describe the underlying physical pro-
    cess as a quantum mechanical interaction between the
    system to be measured and a quantum meter; as a con-
    sequence of the interaction the system and the meter become correlated in a way that the post-measurement state of the meter carries
    information about the system state. The irreversibility of
    the measurement process emerges as a consequence of the
    coupling of the quantum meter to other physical systems
    with large number of degrees of freedom { the environ-
    ment of the quantum meter}. This formulation was first
    introduced by von Neumann in 1930s.

    Based on this premise, a large class of chemical reac-
    tions or biological processes can be described as a quan-
    tum measurement where the biological complex of inter-
    est assumes the role of a quantum meter. The simplest
    scenario with which one can describe a quantum mea-
    surement is the one in which the wave-function describ-
    ing the quantum meter is in a pure state – which is nor-
    mally the lowest energy eigenstate of the meter Hamil-
    tonian Hmeter. This assumption does not require that
    the overall system wave-function is in a pure state – nor
    does it assume zero temperature; it is motivated by the
    fact that to ensure maximal information extraction from
    the system that is being measured, it is desirable to have
    complete information about the initial state of the meter.
    That said, the assumption of an initial pure-state is well
    justified in a pigment-protein complex where the initial
    in particular, measurement of an incident radiation field
    and of the earth’s magnetic field.
    We assume that the broadband optical excitation projects the quantum
    meter into a superposition of eigenstates with eigenenergies that
    are substantially higher than that of the initial ground
    state of the meter.

    Measurement of an external field by a biological quantum meter described
    above. We shall illustrate this with specific reference to
    the cryptochrome protein, a photoreceptor which is the
    leading candidate for hosting the radical pair in the retina
    of birds. This protein contains a co-factor, FAD, which
    absorbs incident light centered around 450 nm to form an
    excited singlet state FAD . The unstable FAD triggers
    a rapid charge transfer across a chain of three trypto-
    phan amino acids, leading to the formation of a radical
    pair state [FAD 􀀀 + TrpH +] in which the electron spins
    are located on spatially separated and distinct molecules.
    The total electron spin is conserved during this fast elec-
    tron transfer, which takes place on a ps time-scale 0.

    On the other hand, we note that optically induced radical
    pairs are also sensitive to weak electric elds; this sensi-
    tivity is due to the different electric dipole moments of
    the singlet and triplet states, which in turn results in an
    external electric field dependent relative phase between
    the two spin states. As a consequence, the singlet-triplet
    oscillations in the excited state can be altered by external
    electric fields. In fact, it is well known that fluctuating
    electric fields can lead to dephasing of singlet-triplet co-
    herence. Taken alone, such dephasing is equivalent
    to a non-referred quantum measurement of the electric
    field. However, in the context of an optically induced
    radical pair in a biological setting with chemical reaction
    products dependent on the singlet-triplet dynamics, the
    underlying electric field sensitivity of the singlet-triplet
    energy difference may facilitate measurement of a local
    electric field.

  4. If I read some of Matt’s articles correctly these are some particles LHC might discover during its new run (cut out and condensed from Matt’s texts):

    A new particle that can produce a W or Z particle in its decays, or even just produce an appropriate disturbance in the W or Z field (called a “virtual particle”, but not really a particle at all.) If the new particles can be produced in pairs (i.e., the particle along with its antiparticle, typically), then it is common for the event in question to include both a W and a Z particle, or virtual particles from both W and Z fields. This can lead to three leptons (electron, muon or tau).

    In some theories, the presence of lepton-like partner particles (such as lepton superpartners in supersymmetry, also called “sleptons”) can participate, replacing the W and Z. Since they decay to leptons or neutrinos all of the time, they can often enhance the number of multi-lepton events compared to events with a W and Z, only a few percent of which produce three leptons.

    Another possibility is a new particle that can produce a top quark and top anti-quark in its decay. Then if that particle is produced in pairs, two top quarks and two top anti-quarks will result, leading to four W particles (one from each top quark or anti-quark.) While four leptons are possible, three leptons are much more likely (and even in four-lepton events it is common that one goes undetected.)

    [If a new particle can decay to a W or Z particle (along with other known particles), a particle/anti-particle pair could produce a W and a Z together. If a particle can decay to a top quark and a top anti-quark, then production of a new particle/anti-particle pair leads to the presence of four W particles. Four W particles also emerge if a new particle can decay to two Higgs particles (h). ]

    A new particle that can directly decay to a W and a Z. Another possibility, if the Higgs were heavy enough to often decay to a W+ and W- particle, would be a new particle that could decay to two Higgs particles; if the new particle were produced, the chain of decays could give four W’s and therefore up to four leptons in an event (though this particular possibility is now rather constrained by Higgs-particle searches.)

    A pair of particles that carry strong nuclear forces (such as a gluino, the gluon’s superpartner) which decay to quarks and/or antiquarks plus a chargino (a mixture of superpartners of the W particles and the charged Higgs particle that arises in supersymmetry) or a neutralino (a mixture of superpartners of the photon, Z, and the neutral Higgs particles.) The chargino and neutralino can then in turn decay to a lighter neutralino [the lightest superpartner, or “LSP”] plus a W and Z particle, or plus W and Z virtual particles, in the process producing three (and very rarely four) leptons/anti-leptons. If (see Figure 2) a chargino and neutralino are produced together, and these decay to an a charged lepton or neutrino and a superpartner of a charged lepton or neutrino, following which the superpartner decays itself to a charged lepton or neutrino plus an LSP neutralino, then every time a chargino and neutralino are produced one obtains four particles that are charged leptons or neutrinos (or their antiparticles.) In R-parity violating variants of supersymmetry, the lightest superpartner (LSP), often a neutralino, can decay to known particles, including (for a neutralino) one or two charged leptons. This can cause a large fraction of events in which superpartners, such as squarks, are produced in pairs to include three or four leptons.

    Is this pretty correct?

  5. So I just saw Matt’s article here. Is the minimalistic realistic version of the Supersymmetric Standard Model still what physicists hope to discover? And in which 10^- x meter realm would one expect the squarks, gluinos, sleptons and sneutrinos and the heavier higgs versions?

    1. wouldn’t say ‘physicists’ hope discover any specific thing; there are a number of groups and factions each of which support different theories and approaches. Simple supersymmetry has been hit hard by the LHC’s inability to find any sparticles in its previous energy range, but supersymmetry as a whole is not out. However recently focus has shifted to more marginalized theories and their proponents will be hoping for a surprising result.

  6. So regarding the new run of LHC – the LHC experiments will be able to measure particles down to 10^-19 meters. At what (attometer ?) scales would we expect which particles? The different quarks, high energy neutrino, and which supersymmetric particles?

    1. The LHC is already in supersymmetry territory and has been knocking back theories for a while. At its new energy it will probe further into possibly supersymmetric particles (Such as selectrons.) as well as look for dark matter particles and things like axions. At this point the LHC will basically look for everything. (Though neutrinos of any kind are always very tricky to pin down.)

    1. The paper in the article is an attempt to quantify how reliant on quantum effects various things are. It’s little more than an attempt way to organize things on a scale of ‘quantum’ In the case of the Robin its detection of magnetic fields is theorized to be completely reliant on quantum effects.

      The paper is… interesting but doesn’t really add anything new. It could even hinder research by labeling various approaches as unimportant.

  7. Hi Matt,

    Are you familiar with physicist Thomas Campbell and his “My Big TOE” theory? I think you will really dig it!

    1. An issue would be the use of Bohmian mechanics which basically says that the universe is deterministic, clockwork if you like. This is the latest in a series of attempts to remove the random from QM and previous theories have not fared well.

      This is certainly serious physics, Hawking himself has a similar theory, but at present there isn’t much in the way of evidence for it. Even the traditional big bang doesn’t necessarily require a singularity and universal start.

      1. The correct explanation is not Bohmian mechanics. It’s de Broglie’s double solution theory. In de Broglie’s double solution theory there is the physical wave which guides the particle and the wave-function wave which is statistical, non-physical and is used to determine the probabilistic results of experiments.

        Particles of matter move through and displace the dark matter.

        In a double slit experiment it is the dark matter that waves.

        1. Field is fundemental OK,
          then how inverse compton scattering occurs (blue shift) – increase in wavelength of photons instead of speed of light ?

          Particles move thru dark matter is like you move through a crowed interacting with people – less interact less mass, more interact more mass (higgs) ?. Then photon also must get mass ?

          1. The faster a particle of matter moves with respect to the state of the dark matter in which it exists the greater the displacement of the dark matter by the particle the greater the relativistic mass of the object.

    2. “Iam” is not sedimentary “sediments of informations”. Therefore nondeterministic.
      The quantum electrodynamic vacuum or QED vacuum is the field-theoretic vacuum of quantum electrodynamics. It is the lowest energy state (the ground state) of the electromagnetic field when the fields are quantized. When Planck’s constant is hypothetically allowed to approach zero, QED vacuum is converted to classical vacuum, which is to say, the vacuum of classical electromagnetism.
      So the unitarity of gauge symmetey is broken into negative squared one.
      It is the action of the inaction.
      For example, we breath nitrogen (inert or no action) and again breath out – but not without action.

    3. I was actually thinking of George EC Sudarshan’s, Sinha’s et al. theory of a superfluid vacuum state….. is this relevant in this context?

  8. Matt,

    One question I have is whether this new information has indeed undermined all of the theories of eternal inflation, which seemed to be implied by a post over at the Starts with a Bang blog (https://medium.com/starts-with-a-bang/ask-ethan-74-gravitational-waves-c21e701f9bde).

    If that were true I would think it would be pretty big news considering the prominent cosmologists who have been proposing it over the years. Your thoughts would be greatly appreciated.

  9. Energy is conserved in this Universe, so it has to go somewhere. And where did all of that energy inherent to spacetime go?
    Universe governed by quantum laws, and that means quantum fluctuations happened even before so called big bang.
    We don’t understand all the caveats of inflation, or of dark energy, for that matter, including whether or not they’re related. But just a generation ago, we didn’t know anything at all about the energy inherent to spacetime, and now we know it to be an integral part of our Universe’s history!
    So when we say the Universe “Started With A Bang,” that’s just our observable Universe, and all the matter and energy in it.
    In physics, that’s also known as nothing, and it’s where everything came from, and where everything will return to in the future.

    So there is no Spacetime Geometry and its associated General relativity – unless we have solid proofs ?

    1. “Rest mass and Time dilation cannot coexist”.
      Special relativity, time dilation – or Spontaneous Symmetry Breaking is OK – because through non conservation of mass, they explain the CP violation – within observable universe.
      Only the general relativity’s topological geometry is confusing ,

      1. “Rest mass and Time dilation cannot coexist” – is my original statement.
        Equivalence principle is only for the Clock, not for the Mass ?

        Increase in mass makes the clock more slow. More shorter the distance more energy, more accleration – also slows down the clock. At one point “Equals them” ?
        But there will be no singularity, the light will take very, very long time to travel (very very slow).
        Because the speed of light is Constant, there should be enormous space !
        So there is no Rest mass.

        Mass is like Penrose triangle. But if we accept, the rest mass, it become like Penrose stairs – an impossible mathematical connection (may be from extra dimension) – making undisputable chicken-egg arguments ?

    2. Actually on the universal scale it seems that energy is not conserved. (This is because to have ‘energy’ make sense you need a single reference frame. This is similar to how there is no one ‘time’ in the universe but it changes depending on what reference you use.) And on top of that you ahve dark energy which seems to literally spring from nothing.

      1. Our Universe is a larger version of a galactic polar jet.

        It’s not the Big Bang; it’s the Big Ongoing.

        Dark energy is dark matter continually emitted into the Universal jet.

        Yes, I realize this is not the ‘standard’ explanation. However, it is more correct than the Big Bang.

      2. Agreed completely Mr. Kudzu.
        Nearly it is like George Frederick Chapline’s Dark-Energy star.

        For Gravitational waves, there is a need for that reference frame. It is like bringing infinity into mathematics. But it is there – there is energy.
        If the spacetime is a random and dynamical process, the inflation may be associated with time rather than energy – while energy non conservation between “space and energy” ?

        You and Chapline are physicst – Iam not.

        1. “Where there is change, there is TIME”
          The “PHASE” change in space-energy give this time. When enormous space appears, we feel the inflation.
          In order to reconcile quantum mechanics with black holes, Chapline theorized that a phase transition in the phase of space occurs at the event horizon.

          In WU experiment, in weak interaction, the MIRROR IMAGE is violated in P – conservation, due to the creation of mass.

          This experiment resulted from the W and Z gauge bosons of the weak interaction only interacting with left-handed matter particles and right-handed antimatter particles. So the left handed NEUTRINOS weakly interacting and RIGHT handed neutrinos with dark energy. The “phase change” makes both the Right and Left handed neutrinos massive.

          In below impodsible triangle video, in reality there is no complete triangle. There is a big gap between the ends (PHASE change).
          But at Weinberg angle Qw = 28,74°, the SYMMETRY IS BROKEN, and the triangle appears complete (Massive).
          If this processes is random and dynamic, it appears “everywhere (quantum reality) – like in String Theory’s multiverse kalaidascope.

          Impossible Escher-style triangle found in real life!: http://youtu.be/rRSeHeHAZmw

          1. Particle physicists are using astronomical data to calculate the mass of small particles. These calculations do rely on some of the ASSUMPTIONS in the Standard Model of Cosmology as being correct. Specifically, that the universe has a flat geometry and that dark energy can be described by the cosmological constant These assumptions are not guaranteed.

            In 2012 we know MASS got from Higgs mechanism – Mass loss (Beta decay) became Higgs field. But the Stanfard Model says Neutrinos are massless – so to create “TIME or phase change” we must include Right-Handed neutrino.

            The right-handed neutrinos would not feel the weak interaction, their mass would not depend upon the Higgs Field. Instead, their mass would probably emerge from a completely different very high energy mechanism most likely making the right-handed neutrino extremely heavy – may be out of the flat universe.?

            For a supernova, almost all of the energy produced is in the form of neutrinos. So neutrinos are an integral part of the explosion mechanism for supernovas and in the production of heavy elements created during the explosion.

            But bring metastable mass (they annihilate one another, or AGAINST the CP VIOLATION) to our flat geometrical universe ? ?

          2. Now have I got this right, Veeramohan. in the particle zoo some of the little fellas interact with some of the others that they have a compatibility with, some in the now dimension and some in the other dimension. Together, and at a particular moment in time, they make a whole and a structure which is the basic building block of reality?

          3. Yes Mr. Jonblackall I think also,
            the Higgs mechanism was originally for strong force, to get mass for masless gluons. By this processes, Photons also must be massive. But something Prevents it – and the radioactive decay is more strange one ?

        2. The masses of W, Z bosons and masslessness of photons was decided by degrees of freedom.
          Three degrees of freedom, too little for the W and Z bosons. For higgs, one degree of freedom is too much. So mathematical trick connection between two Phase changes of an impossible triangle – or a physical reality at the middle of the cone, of Mexican hat ?

  10. Thanks Matt, you are a breath of fresh air! I know am out of my depth but thanks for being kind to me. Last question on this. Does it mean that even at the speed of light radiation, photons etc travel as a wave? I ask the question because if there is a limit to speed a wave suggests the potential for more speed.

    1. There re two types of particle-wave things (Wavicles?) in the universe, those with rest mass that must travel slower than light and those with no mass that must always travel at the speed of light. But all waves have their speed limits. For example sound waves can only travel about 300 meters per second in air, no faster. Adding more energy to a wave usually makes it larger, not faster.

    1. The amplitude of a wave is just its power. This is determined by whatever created the wave. The bigger the speaker, the louder the sound.

      For most waves wavelength is speed x frequency, all three variables being related. In the case of microwaves and other EM radiation the speed is set at c (the speed of light.) so only wavelength and frequency will change. double the frequency, halve the wavelength.

      For more trying googling the ‘wave equation’ and looking at some of the more simple links. (The hardcore physics links can be very overwhelming.)

    1. Which actually disproves the theory.

      Our Universe is a larger version of a galactic polar jet.

      Dark energy is dark matter continuously emitted into the Universal jet.

          1. The rotation about a preferred axis and the directionality of the galaxy clusters both refute an asymmetric BB/inflationary cosmology universe and are both evidence that our Universe is a larger version of a galactic polar jet.

            Which is germane to this article as it has to do with cosmic inflation.

            Forget the BICEP2 data no longer supporting cosmic inflation. Our universe rotating about a preferred axis and the directionality of the galaxy clusters refutes it.

          2. Should have said:

            The rotation about a preferred axis and the directionality of the galaxy clusters both refute an [isotropic] BB/inflationary cosmology universe and are both evidence that our Universe is a larger version of a galactic polar jet.

          3. The three most incorrect notions in the history of physics:

            1. Whatever nonsense is being made up in order to not understand the particle always travels through a single slit in a double slit experiment and it is the wave in the mass which fills ’empty’ space which passes through both.

            2. The Big Bang.

            3. The Earth is stationary and the center of the Universe.

  11. Cosmic inflation does have many sources of indirect evidence that have helped some of the versions of the theory to make it all the way from 1980 until today with still relevance as a relevant theory that is worth to invest in some very expensive experiments to be put to the test.

    Kind regards, GEN

    1. There is zero evidence of a “Big Bang”. All of the evidence associated with cosmic inflation are more correctly attributed to our Universe being a larger version of a galactic polar jet.

      1. On the contrary, there are many pieces of indirect evidence in favor of something like cosmic inflation happening at the very beginning of our universe.

        Besides this, the “Bang” in “Big Bang” is cosmic inflation itself, a brief period of such a rapid expansion of our Universe that it was initially understood as an explosion as the very beginning of our universe.

        The fact that in the CMB signal the differences in temperature are so incredibly small is an indirect evidence of inflation, and the fact that those tiny differences of temperature exist and how small and random they are are also a different kind of indirect evidence of cosmic inflation.

        The fact that our universe now is “flat” is also an indirect evidence of cosmic inflation.

        But then again, scientists are looking for more solid evidence of cosmic inflation beyond these “morsels of truth”.

        Kind regards, GEN

        1. Even the founders of the Inflationary Cosmology/Big Bang/Cosmological Constant (BB) model are starting to understand it is absurd nonsense.

          ‘The Inflation Debate’
          scientificamerican.com/article/the-inflation-summer/

          “In Brief
          Cosmic inflation is so widely accepted that it is often taken as established fact. The idea is that the geometry and uniformity of the cosmos were established during an intense early growth spurt.
          But some of the theory’s creators, including the author, are having second thoughts. As the original theory has developed, cracks have appeared in its logical foundations.
          Highly improbable conditions are required to start inflation. Worse, inflation goes on eternally, producing infinitely many outcomes, so the theory makes no firm observational predictions.
          Scientists debate among (and within) themselves whether these troubles are teething pains or signs of a deeper rot. Various proposals are circulating for ways to fix inflation or replace it.”

          Anything which has “infinitely many outcomes” is not disprovable which means it is not a theory.

          Our Universe is a larger version of a galactic polar jet.

          Dark energy is dark matter continuously emitted into the Universal jet.

  12. Our Universe is a larger version of a galactic polar jet.

    Was the universe born spinning?’
    physicsworld.com/cws/article/news/46688

    “The universe was born spinning and continues to do so around a preferred axis”

    Our Universe spins around a preferred axis because it is a larger version of a galactic polar jet.

    ‘Mysterious Cosmic ‘Dark Flow’ Tracked Deeper into Universe’
    nasa.gov/centers/goddard/news/releases/2010/10-023.html

    “The clusters appear to be moving along a line extending from our solar system toward Centaurus/Hydra, but the direction of this motion is less certain. Evidence indicates that the clusters are headed outward along this path, away from Earth, but the team cannot yet rule out the opposite flow. “We detect motion along this axis, but right now our data cannot state as strongly as we’d like whether the clusters are coming or going,” Kashlinsky said.”

    The clusters are headed along this path because our Universe is a larger version of a polar jet.

    It’s not the Big Bang; it’s the Big Ongoing.

    Dark energy is dark matter continuously emitted into the Universal jet.

    1. This is not an advertising site for commenters’ personal ideas; it is a website for discussing mainstream science. There are other websites that will welcome these sorts of speculative notions, but it is not appropriate to make these types of comments here, especially since they are irrelevant to this article. Please desist.

      1. By mainstream science are you referring to the group of individuals who are incapable of understanding the particle always detected traveling through a single slit in a double slit experiment is evidence the particle always travels through a single slit?

        Is this group of individuals capable of understanding in a boat double slit experiment the boat travels through a single slit even when you close your eyes?

        Q. Why is the particle always detected traveling through a single slit in a double slit experiment?
        A. The particle always travels through a single slit. It is the associated wave in the dark matter which passes through both.

        If “mainstream physics” is ever interested in understanding what occurs physically in nature then it should understand particles of matter move through and displace the dark matter; including ‘particles’ as large as galaxies and galaxy clusters.

        What ripples when galaxy clusters collide is what waves in a double slit experiment; the dark matter.

        Einstein’s gravitational wave is de Broglie’s wave of wave-particle duality; both are waves in the dark matter.

        Dark matter displaced by matter relates general relativity and quantum mechanics.

        I desist.

          1. I don’t know what you are doing, but if you can’t understand the particle is always detected traveling through a single slit in a double slit experiment because it always travels through a single slit then one thing is for sure, you aren’t doing science.

  13. Nice pun in the title, but it makes it sound like it was the only piece of evidence for cosmic inflation…

  14. In a piece on the BICEP-2 issue in Physics World, Neil Turok is quoted as saying: “For the past 35 years, theoretical physics has been an extravaganza of model-building” [adding that theories have] “sort of run amok”.

    Theoretical physics needs to put more effort into finding new theories of principle.

    1. Just because no one has actually succeeded in finding one doesn’t mean there isn’t plenty of effort. New ideas only show up once every few decades. And often they don’t show up because you are looking for them. For example, string theory was not invented by people trying to find a theory of quantum gravity. They were trying to make sense of experimental data involving the scattering of hadrons. So it’s all fine to make generalized statements such as your final sentence… but such statements ignore the intricacies and surprises that pervade intellectual history.

      1. If string theory was truly a theory of principle, it would have been able to make definitive predictions by which it could tested. It was not and could not.

        I know the history of physics just as well as you do. The community must be open to new ideas that come from the fringes of academia, usually from relative unknowns. We should be thankful that Planck championed Einstein when he was a nobody. Would that happen today? I don’t think so.

        1. I saw Tom Banks champion Lubos Motl when he was a nobody. He was a prodigy and wrote a paper at the age of 20 that Tom Banks noticed immediately. In this age of blogs and open communication, I think it is potentially much easier.

          You’re obviously very confident in your opinions, but that doesn’t make them right.

          1. And by the way, string theory definitely made predictions. It made lots of them… for hadron physics. They were wrong and the theory was falsified. Later it was repurposed for quantum gravity. It is only in that context that it hasn’t made definite predictions (but note it is often quite predictive in any given universe — but it just doesn’t tell us which one we are in.)

          2. I think Lee Smolin and Garrett Lisi would have been a better example.

            If you are betting on string theory and Motl, good luck with those bets.

            And you seem even more confident and insistent in your opinions, but that does not make you right either.

            1. Who said I was betting? I haven’t worked on string theory very much in my career, and only when it was technically useful for solving quantum field theory problems. I also haven’t worked with Motl. Personally I don’t see any point in this conversation, because you’re not interested in actually addressing my comments.

          3. Sorry, but I think Turok’s comment should be seriously and widely addressed. Do people realize how dominant ad hoc model-building has been over recent decades? Do people know the difference between ad hoc model-building and theories of principle? Do people appreciate the dangers of limiting theoretical physics to model-building? Are new theories of principle too much to hope for? If they are still possible, where are they?
            Would the theoretical physics community be welcoming or reactionary towards a radical new set of physical principles.

            That’s all I wanted to say, and again, sorry if it was not relevant to your concerns.

          4. ummmm…. but Motl still *is* a nobody. Young people have never heard of him. Perhaps you could think of a better example?

        2. Robert,

          There is knowledge by experience, and knowledge by deduction. If things are working right and together, inductively and deductively, we are taken to some deep insights regarding knowledge that allows us to move forward toward the experimental. Any opinion, from my point of view that is spoken from knowledge of experience only, does not help the theoretic development so once has to acquiesce toward doing and working deductive powers for the next step for testing. You could not have an opinion otherwise?

          Best,

          1. Robert,
            …….as an example…..you may have ideas about self similarity and show cosmological relations to the designs of orbitals. Empirically true?

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A decay of a Higgs boson, as reconstructed by the CMS experiment at the LHC

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