...as well as anti-quantum, anti-string...
For more than 30 years, Roger Penrose would be offering many irrational and wrong criticisms of the cosmic inflation. He didn't stop after the publication of the discovery of primordial gravitational waves by BICEP2. On Friday, instead of hiding somewhere in a closet, he went to Ira Flatow's show, Science Friday, and displayed more self confidence than ever:
Instead of a single counter-argument, we hear lots of things "it must be wrong because I say so". The discovery by BICEP2 is probably OK, he says, but the interpretation is completely wrong. It cannot be because of gravitational waves because there should be no gravitational waves in the early Universe.
He has "alternative theories" to explain the B-modes (no, when it comes to B-modes, he wouldn't even say that they have something to do with the polarization of the cosmic microwave background). What are his "alternative theories"? We hear lots of promotion of cyclic cosmologies. But they are the #1 loser that are really disproved by the discovery of the B-modes. They just predict that there should be no B-modes.
Penrose's vague comments about pre-Big-Bang cosmologies don't help his case, either. The B-modes are clearly an after-Big-Bang phenomenon.
It takes some time to isolate what he could possibly consider "his alternative explanation of the B-modes". But if you listen for a while, he says that the B-modes were due to the ancient magnetic fields, not gravitational fields. But this claim doesn't pass the first test of a smart high school student who knows something electrodynamics. She knows that in the vacuum, Maxwell's equations are linear and they obey the superposition principle. It means that the presence of the background electromagnetic fields doesn't change the propagation of the electromagnetic waves in the foreground.
Can the magnetic fields influence the atoms the emitted the microwave radiation so that the temperature depends on the polarization? Perhaps but I don't think so. Thermal equilibrium is thermal equilibrium. Whether there are some background electromagnetic fields or not, photons in all modes will be led to have the same temperature. A more detailed analysis would be needed but I don't think that there exists a single paper that would even mention such an alternative explanation. There exists a huge problem with the "wavelength" of the magnetic fields in Penrose's "alternative" models. Note that the dominant wavelengths are measured in hundreds of millions of light years today and they had been really long even during recombination. Magnetic fields constant over these long distances are really electromagnetic waves with very tiny frequencies and those had no reason to be significantly produced without inflation.
Let me explain the need for the gravitational waves as follows: Before the cosmic microwave photons are emitted, the atoms and everything there is moving at low, non-relativistic speeds. When it's so, the variations of the temperatures and densities are derived from variations of scalar fields – there are no tensor fields in non-relativistic approximation of gravity – and the only vector-like variation is the gradient that has a vanishing curl. But curl-less variations of the CMB are by definition the E-modes. The vectors (electric, magnetic fields) are nothing else than what we want to calculate – the spectrum and polarization of the CMB radiation – so we simply need tensors.
The only way how some "tensorial" background may imprint itself into the CMB is that the background contains some patterns in the spatial components \(g_{ij}\) of the metric tensor, i.e. if there are gravitational waves moving at the speed of light for which the non-relativistic (Newtonian) approximation of gravity breaks down. The gravitational waves stretch one direction and shrink the perpendicular one, inducing a temperature difference for the two polarizations, too.
Penrose's monologues on Flatow's show combine almost all the key errors that Penrose has ever promoted about fundamental physics. Gravitational waves shouldn't be there because he and his crackpot physician collaborator Stuart Hameroff want to link gravity to consciousness, or something like that, and there were no conscious humans during recombination. So gravitational waves are not allowed. But the principle of the gravitational field and the gravitational waves is completely analogous to their electromagnetic counterparts. The spins differ; the interaction constants and typical energy scales differ. But if one may exist, so can the other. These fields and waves don't differ in their interpretation and they also enter the interpretation of quantum mechanics "equally". To attempt to "ban" gravitational waves (and their composition from gravitons, something that isn't needed for the B-modes at this point) is as indefensible as to "ban" the light.
When Flatow correctly asks how Penrose's alternative theory explains things, Penrose answers that there is a puzzle, but "the puzzle is there anyway". There are voids, blah blah blah, and there's a puzzle where the primordial [magnetic] waves [that have nothing to do with the B-modes here] come from. Except that in inflationary cosmology, there is no puzzle about these matters whatsoever. Cosmic inflation predicts what the later various are unequivocally. For Penrose, magnetic fields in voids "prove" a history before the Big Bang. He immediately gets drifted away to weird speculations about "eons" from his CCC. He doesn't seem to grasp the concept that a cosmological theory claiming to say something about these early epochs should be able to say something about the B-modes. Or he's just plain denying the inconvenient evidence, trying to escape elsewhere.
At 7:50, Flatow says that Penrose also has a problem with quantum mechanics. It doesn't make sense. It's equivalent to the statement "Hey, Roger, you are a crackpot when it comes to all of modern physics, anyway", and you would expect Penrose to defend himself. Instead, he says, "Well, it [QM] doesn't [make sense]." Holy cow. Flatow reminds Penrose that it's the most successful theory that there ever was. So Penrose says it is fantastic but the trouble is that it is based on two mathematical schemes, Schrödinger's equations and observations. Except that there is no trouble whatever. The observations are directly (probabilistically) predicted from the objects that appear in the Heisenberg (or for eternal beginners like Penrose, Schrödinger) equations of motion. There is no schism in quantum mechanics. That theory applies to everything in our world including the bodies of observers. Penrose repeats lots of the basic wrong things about inapplicability of QM to observers, about Schrödinger's cats, about everything. I won't discuss this junk again.
"It's not just I who is saying that; Schrödinger was saying it, too." That's great but Schrödinger was wrong about these things, too, a simple example why such cherry-picked ad hominem "arguments" don't have any weight in science. A difference is that Penrose is wrong about these elementary questions even 80 years later than Schrödinger. He has had 80 extra years to learn the basics of modern science – and to see 80 extra years of experiments confirming quantum mechanics to every detail – than Schrödinger but he has still failed. So sociologically, Penrose's stubbornness or stupidity is much greater than Schrödinger's.
Flatow has understood what various people say about these matters so he's trying to offer Albert Einstein as an ally to Penrose. Quantum mechanics is incomplete, like Einstein has said, right? But Penrose answers that it's worse than that. Penrose claims that quantum mechanics is internally inconsistent. Holy crap, how obsessed with a delusion you have to be to make such claims. "If you apply Schrödinger's equations to the measurement, you don't get the results you should get." Except that you do get exactly what is predicted unless you deliberately distort what quantum mechanics actually predicts and how it links its mathematical objects to the observations and perceptions.
Penrose says that quantum mechanics fails when there is too much mass around; then the rules change. But they don't change an iota. Quantum mechanics is perfectly valid for any concentration of mass, including black holes.
At 10:40, Flatow asks about the "fashion", namely string theory. So string theory is "fashion" even though there were/are other reasons to study string theory. But what he really objects to are not strings (which may be a good idea) but extra dimensions. But holy cow, Dr Penrose, the extra dimensions are not arbitrarily added extra decorations. They are predictions of string theory. They are absolutely needed to have an internally consistent theory. It's really painful that after the decades in which you unsuccessfully tried to talk about string theory, you are still failing to learn these basic things from the first or second chapter of every string theory textbook.
He believes that there "must" only be three dimensions; there are problems with extra dimensions. Except that there are no problems whatsoever. The consistency of the theory not only allows but requires the extra dimensions. I remember Andy Strominger's report on a talk by Penrose in which he tried to use words like "conifold" and he would claim that there were singular points in these manifolds and/or their moduli spaces which implied an inconsistency. Except that it's exactly the main conifold-related result of the Second Superstring Revolution in the mid 1990s that the dynamics on these conifolds is completely smooth and well-defined. In fact, by mirror symmetry, it is exactly equivalent to the dynamics on a smooth Calabi-Yau manifold, and so on. When Penrose is talking about extra dimensions and you want to know when he is just saying pure rubbish, there is a simple criterion to tell: His lips are moving.
The very general suggestion that "strings are OK but the other structures are not" is outdated, too. The revolution of the mid 1990s has shown that strings are not truly fundamental in the ultimate design of the theory. They're just light degrees of freedom that become importantly in the (weakly coupled stringy) limits of the whole theory. There are more important properties of the theory that maintain theories importance even away from these weakly coupled limits and non-perturbatively.
Another flabbergasting "argument" in favor of 3+1 dimensions that Penrose offers on the show is that he has only developed a formalism for spinors etc. in 3+1 dimensions. That's great but there are lots of other formalisms for spaces and superspaces and their cousins in a wide variety of different dimensionalities. When it comes to formalisms for geometry, Dr Penrose, yours is just a tiny seed of sand on a rather large beach (I say it despite the fact that I was exposed to Penrose's and Rindler's book as a high school kid, so it has probably had a significant impact on my thinking and sentiments). It's an example of self-centrism run amok if you think that some ideas – or, indeed, dimensionalities – must be wrong just because you haven't developed a formalism for them. There are other special formalisms and even if "no special formalism" is possible in a theory or a dimensionality, it doesn't imply that the theory or dimensionality is wrong!
Some promotion of twistor theory that doesn't go beyond mid 1960s. He is largely unaware of any technicality in the twistor minirevolution of the last decade although he does mention the developments. At least he correctly says that those things reformulate the known laws of physics, so they are not alternative theories giving different predictions for experiments. Penrose mentions Arkani-Hamed; Witten isn't working on twistors these days. What made me laugh was Penrose's statement that "[Arkani-Hamed and pals] are only looking at limited areas of the twistor theory; they haven't used the main body of the subject yet". LOL. The contemporary work using twistor theory is about 100 times deeper than what Penrose has ever said about those matters. Everything meaningful that Penrose has ever said about twistors is summarized in the introductions to almost every review of the recent work on twistors because it's the "schookid's prerequisite" needed for a much more complex and structured body of work.
At 17:30, listeners' questions begin. Chris offers an incoherent monologue about the Big Bang singularity, mixing it with black holes, inflation. For Penrose, the Big Bang singularity is very special because it disappears when you stretch it to infinity. He uses this meme to say that it's conformally equivalent to the infinite future along the conformal cyclic cosmology. Completely wrong.
At 20:00, Flatow asks about the multiverse. It's a different thing – the universes are separated by space in the multiverse but time in cyclic cosmology. Well, a multiverse cosmology really deals with lots of universes that are separated both in space and also in time but he wanted to show he is special again. He is also asked about the anthropic reasoning. It's not quite his, either. Penrose is presenting everything as if he had "the right theory for everything". Except that his theories explain virtually nothing from the set of issues that is addressed by the theories he wants to question or replace which means that by switching to "his" viewpoint, he is not addressing any of the issues. He is just attacking the theories that do.
New physics is made necessary by puzzling observations.
Penrose is trying to make the Hawking radiation look like a no big deal because the temperature is low. It's quite painful. The importance of the Hawking radiation is not that the temperature is high for the known astrophysical black holes (it would be high for very small black holes!). The importance is that it is a theoretical development showing the inevitable consequence of quantum mechanics for the behavior of objects in general relativity. After a googol of years, the black holes will evaporate, but a googol (the number linked to Hawking) is nothing compared to the eternity (linked to Penrose himself), we hear. How modest. The eternity is long when expressed in seconds but nothing qualitative (except for the Poincaré recurrence after a googolplex of years) will be taking place in the nearly empty de Sitter space so the eternity is less interesting scientifically than the finite (and sometimes very short) epochs studied in cosmology (and black hole physics). Moreover, Penrose hasn't discovered any Hawking-radiation-scale insight about the "eternity" so it's silly for him to suggest that he "owns" the eternity more than anyone else does.
A few correct comments on the dark energy (a term Penrose dislikes). It is the 1917 cosmological constant invented by Einstein for wrong reasons. Just a number, nothing else to be discovered about the C.C., except that the value is confusing. I sympathize with these comments although the depth of wisdom and deeper mechanisms behind this simple "number" may be substantial (or may be limited; we cannot be sure today). Penrose correctly argues that there's no particle linked to the C.C. because the C.C. is a constant, and it therefore isn't varied like the Higgs field.
I would normally love such interviews but he's so wrong about such a huge majority of the things he says (certainly about the basics of things that he calls "fashion, faith, and fantasy") – and his wrongness seems to be due to some narcissism run amok – that the ultimate feelings are unfortunately much less positive.
For more than 30 years, Roger Penrose would be offering many irrational and wrong criticisms of the cosmic inflation. He didn't stop after the publication of the discovery of primordial gravitational waves by BICEP2. On Friday, instead of hiding somewhere in a closet, he went to Ira Flatow's show, Science Friday, and displayed more self confidence than ever:
Sir Roger Penrose: Cosmic Inflation Is ‘Fantasy’ (click this and click the "LISTEN" button)In the 27-minute interview, he reminds us about the book "Fashion, Faith, and Fantasy" about "string theory, quantum mechanics, and inflation," respectively, that he has been writing for a decade. Whenever he is asked a technical question, he laughs and closes it with the suggestion that it is surely silly to talk about such questions on a science show.
Instead of a single counter-argument, we hear lots of things "it must be wrong because I say so". The discovery by BICEP2 is probably OK, he says, but the interpretation is completely wrong. It cannot be because of gravitational waves because there should be no gravitational waves in the early Universe.
He has "alternative theories" to explain the B-modes (no, when it comes to B-modes, he wouldn't even say that they have something to do with the polarization of the cosmic microwave background). What are his "alternative theories"? We hear lots of promotion of cyclic cosmologies. But they are the #1 loser that are really disproved by the discovery of the B-modes. They just predict that there should be no B-modes.
Penrose's vague comments about pre-Big-Bang cosmologies don't help his case, either. The B-modes are clearly an after-Big-Bang phenomenon.
It takes some time to isolate what he could possibly consider "his alternative explanation of the B-modes". But if you listen for a while, he says that the B-modes were due to the ancient magnetic fields, not gravitational fields. But this claim doesn't pass the first test of a smart high school student who knows something electrodynamics. She knows that in the vacuum, Maxwell's equations are linear and they obey the superposition principle. It means that the presence of the background electromagnetic fields doesn't change the propagation of the electromagnetic waves in the foreground.
Can the magnetic fields influence the atoms the emitted the microwave radiation so that the temperature depends on the polarization? Perhaps but I don't think so. Thermal equilibrium is thermal equilibrium. Whether there are some background electromagnetic fields or not, photons in all modes will be led to have the same temperature. A more detailed analysis would be needed but I don't think that there exists a single paper that would even mention such an alternative explanation. There exists a huge problem with the "wavelength" of the magnetic fields in Penrose's "alternative" models. Note that the dominant wavelengths are measured in hundreds of millions of light years today and they had been really long even during recombination. Magnetic fields constant over these long distances are really electromagnetic waves with very tiny frequencies and those had no reason to be significantly produced without inflation.
Let me explain the need for the gravitational waves as follows: Before the cosmic microwave photons are emitted, the atoms and everything there is moving at low, non-relativistic speeds. When it's so, the variations of the temperatures and densities are derived from variations of scalar fields – there are no tensor fields in non-relativistic approximation of gravity – and the only vector-like variation is the gradient that has a vanishing curl. But curl-less variations of the CMB are by definition the E-modes. The vectors (electric, magnetic fields) are nothing else than what we want to calculate – the spectrum and polarization of the CMB radiation – so we simply need tensors.
The only way how some "tensorial" background may imprint itself into the CMB is that the background contains some patterns in the spatial components \(g_{ij}\) of the metric tensor, i.e. if there are gravitational waves moving at the speed of light for which the non-relativistic (Newtonian) approximation of gravity breaks down. The gravitational waves stretch one direction and shrink the perpendicular one, inducing a temperature difference for the two polarizations, too.
Penrose's monologues on Flatow's show combine almost all the key errors that Penrose has ever promoted about fundamental physics. Gravitational waves shouldn't be there because he and his crackpot physician collaborator Stuart Hameroff want to link gravity to consciousness, or something like that, and there were no conscious humans during recombination. So gravitational waves are not allowed. But the principle of the gravitational field and the gravitational waves is completely analogous to their electromagnetic counterparts. The spins differ; the interaction constants and typical energy scales differ. But if one may exist, so can the other. These fields and waves don't differ in their interpretation and they also enter the interpretation of quantum mechanics "equally". To attempt to "ban" gravitational waves (and their composition from gravitons, something that isn't needed for the B-modes at this point) is as indefensible as to "ban" the light.
When Flatow correctly asks how Penrose's alternative theory explains things, Penrose answers that there is a puzzle, but "the puzzle is there anyway". There are voids, blah blah blah, and there's a puzzle where the primordial [magnetic] waves [that have nothing to do with the B-modes here] come from. Except that in inflationary cosmology, there is no puzzle about these matters whatsoever. Cosmic inflation predicts what the later various are unequivocally. For Penrose, magnetic fields in voids "prove" a history before the Big Bang. He immediately gets drifted away to weird speculations about "eons" from his CCC. He doesn't seem to grasp the concept that a cosmological theory claiming to say something about these early epochs should be able to say something about the B-modes. Or he's just plain denying the inconvenient evidence, trying to escape elsewhere.
At 7:50, Flatow says that Penrose also has a problem with quantum mechanics. It doesn't make sense. It's equivalent to the statement "Hey, Roger, you are a crackpot when it comes to all of modern physics, anyway", and you would expect Penrose to defend himself. Instead, he says, "Well, it [QM] doesn't [make sense]." Holy cow. Flatow reminds Penrose that it's the most successful theory that there ever was. So Penrose says it is fantastic but the trouble is that it is based on two mathematical schemes, Schrödinger's equations and observations. Except that there is no trouble whatever. The observations are directly (probabilistically) predicted from the objects that appear in the Heisenberg (or for eternal beginners like Penrose, Schrödinger) equations of motion. There is no schism in quantum mechanics. That theory applies to everything in our world including the bodies of observers. Penrose repeats lots of the basic wrong things about inapplicability of QM to observers, about Schrödinger's cats, about everything. I won't discuss this junk again.
"It's not just I who is saying that; Schrödinger was saying it, too." That's great but Schrödinger was wrong about these things, too, a simple example why such cherry-picked ad hominem "arguments" don't have any weight in science. A difference is that Penrose is wrong about these elementary questions even 80 years later than Schrödinger. He has had 80 extra years to learn the basics of modern science – and to see 80 extra years of experiments confirming quantum mechanics to every detail – than Schrödinger but he has still failed. So sociologically, Penrose's stubbornness or stupidity is much greater than Schrödinger's.
Flatow has understood what various people say about these matters so he's trying to offer Albert Einstein as an ally to Penrose. Quantum mechanics is incomplete, like Einstein has said, right? But Penrose answers that it's worse than that. Penrose claims that quantum mechanics is internally inconsistent. Holy crap, how obsessed with a delusion you have to be to make such claims. "If you apply Schrödinger's equations to the measurement, you don't get the results you should get." Except that you do get exactly what is predicted unless you deliberately distort what quantum mechanics actually predicts and how it links its mathematical objects to the observations and perceptions.
Penrose says that quantum mechanics fails when there is too much mass around; then the rules change. But they don't change an iota. Quantum mechanics is perfectly valid for any concentration of mass, including black holes.
At 10:40, Flatow asks about the "fashion", namely string theory. So string theory is "fashion" even though there were/are other reasons to study string theory. But what he really objects to are not strings (which may be a good idea) but extra dimensions. But holy cow, Dr Penrose, the extra dimensions are not arbitrarily added extra decorations. They are predictions of string theory. They are absolutely needed to have an internally consistent theory. It's really painful that after the decades in which you unsuccessfully tried to talk about string theory, you are still failing to learn these basic things from the first or second chapter of every string theory textbook.
He believes that there "must" only be three dimensions; there are problems with extra dimensions. Except that there are no problems whatsoever. The consistency of the theory not only allows but requires the extra dimensions. I remember Andy Strominger's report on a talk by Penrose in which he tried to use words like "conifold" and he would claim that there were singular points in these manifolds and/or their moduli spaces which implied an inconsistency. Except that it's exactly the main conifold-related result of the Second Superstring Revolution in the mid 1990s that the dynamics on these conifolds is completely smooth and well-defined. In fact, by mirror symmetry, it is exactly equivalent to the dynamics on a smooth Calabi-Yau manifold, and so on. When Penrose is talking about extra dimensions and you want to know when he is just saying pure rubbish, there is a simple criterion to tell: His lips are moving.
The very general suggestion that "strings are OK but the other structures are not" is outdated, too. The revolution of the mid 1990s has shown that strings are not truly fundamental in the ultimate design of the theory. They're just light degrees of freedom that become importantly in the (weakly coupled stringy) limits of the whole theory. There are more important properties of the theory that maintain theories importance even away from these weakly coupled limits and non-perturbatively.
Another flabbergasting "argument" in favor of 3+1 dimensions that Penrose offers on the show is that he has only developed a formalism for spinors etc. in 3+1 dimensions. That's great but there are lots of other formalisms for spaces and superspaces and their cousins in a wide variety of different dimensionalities. When it comes to formalisms for geometry, Dr Penrose, yours is just a tiny seed of sand on a rather large beach (I say it despite the fact that I was exposed to Penrose's and Rindler's book as a high school kid, so it has probably had a significant impact on my thinking and sentiments). It's an example of self-centrism run amok if you think that some ideas – or, indeed, dimensionalities – must be wrong just because you haven't developed a formalism for them. There are other special formalisms and even if "no special formalism" is possible in a theory or a dimensionality, it doesn't imply that the theory or dimensionality is wrong!
Some promotion of twistor theory that doesn't go beyond mid 1960s. He is largely unaware of any technicality in the twistor minirevolution of the last decade although he does mention the developments. At least he correctly says that those things reformulate the known laws of physics, so they are not alternative theories giving different predictions for experiments. Penrose mentions Arkani-Hamed; Witten isn't working on twistors these days. What made me laugh was Penrose's statement that "[Arkani-Hamed and pals] are only looking at limited areas of the twistor theory; they haven't used the main body of the subject yet". LOL. The contemporary work using twistor theory is about 100 times deeper than what Penrose has ever said about those matters. Everything meaningful that Penrose has ever said about twistors is summarized in the introductions to almost every review of the recent work on twistors because it's the "schookid's prerequisite" needed for a much more complex and structured body of work.
At 17:30, listeners' questions begin. Chris offers an incoherent monologue about the Big Bang singularity, mixing it with black holes, inflation. For Penrose, the Big Bang singularity is very special because it disappears when you stretch it to infinity. He uses this meme to say that it's conformally equivalent to the infinite future along the conformal cyclic cosmology. Completely wrong.
At 20:00, Flatow asks about the multiverse. It's a different thing – the universes are separated by space in the multiverse but time in cyclic cosmology. Well, a multiverse cosmology really deals with lots of universes that are separated both in space and also in time but he wanted to show he is special again. He is also asked about the anthropic reasoning. It's not quite his, either. Penrose is presenting everything as if he had "the right theory for everything". Except that his theories explain virtually nothing from the set of issues that is addressed by the theories he wants to question or replace which means that by switching to "his" viewpoint, he is not addressing any of the issues. He is just attacking the theories that do.
New physics is made necessary by puzzling observations.
Penrose is trying to make the Hawking radiation look like a no big deal because the temperature is low. It's quite painful. The importance of the Hawking radiation is not that the temperature is high for the known astrophysical black holes (it would be high for very small black holes!). The importance is that it is a theoretical development showing the inevitable consequence of quantum mechanics for the behavior of objects in general relativity. After a googol of years, the black holes will evaporate, but a googol (the number linked to Hawking) is nothing compared to the eternity (linked to Penrose himself), we hear. How modest. The eternity is long when expressed in seconds but nothing qualitative (except for the Poincaré recurrence after a googolplex of years) will be taking place in the nearly empty de Sitter space so the eternity is less interesting scientifically than the finite (and sometimes very short) epochs studied in cosmology (and black hole physics). Moreover, Penrose hasn't discovered any Hawking-radiation-scale insight about the "eternity" so it's silly for him to suggest that he "owns" the eternity more than anyone else does.
A few correct comments on the dark energy (a term Penrose dislikes). It is the 1917 cosmological constant invented by Einstein for wrong reasons. Just a number, nothing else to be discovered about the C.C., except that the value is confusing. I sympathize with these comments although the depth of wisdom and deeper mechanisms behind this simple "number" may be substantial (or may be limited; we cannot be sure today). Penrose correctly argues that there's no particle linked to the C.C. because the C.C. is a constant, and it therefore isn't varied like the Higgs field.
I would normally love such interviews but he's so wrong about such a huge majority of the things he says (certainly about the basics of things that he calls "fashion, faith, and fantasy") – and his wrongness seems to be due to some narcissism run amok – that the ultimate feelings are unfortunately much less positive.
Roger Penrose continues his weird anti-ïnflation jihad
Reviewed by MCH
on
April 05, 2014
Rating:
Reviewed by MCH
on
April 05, 2014
Rating:
No comments: