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Various thoughts and advertisements! Posts before 29 August 2026 are an archived copy of public Facebook posts. Comments? Email me.

Excess Mortality During India's COVID-19 Pandemic

Updated 1 July 2022

Recorded video of an important discussion hosted by the Indian Scientists Response to COVID-19. The panel had Rukmini S, Shankar and Prabhat Jha and discussed estimates of excess mortality during the pandemic. I learned a lot while moderating the discussion and I would recommend the entire video.

https://youtu.be/XiByxEeM1X4

The discussion is strictly scientific but this question has broader implications.

The context for the discussion is WHO’s estimate, released a couple of months ago, that there had been about 4.7 million excess deaths in India in 2020-21 due to the COVID-19 pandemic — about ten times the official figure. India is a large country but even in per-capita terms this is an extremely high toll. It puts India in the sorry company of countries like the United States that are well known to have mismanaged the pandemic.

This number is important, not just because we owe it to those whom we lost to at least count them, but also for those who are living. The pandemic served as a test of the public health system and of governance. Therefore an analysis of how these systems performed is revealing and must be used for reform and course-correction.

On the one hand, this high toll reveals systemic weaknesses in our healthcare system. Moreover, the lack of basic social security meant that people were unable to take the steps necessary to protect themselves.

But there is a second question. Given these systemic weaknesses, could India have done better if its government had simply taken better policy decisions during the pandemic?" It is clear that the answer is “yes”.

What is more, the government of India clearly agrees with this. The true death toll shows the failure of its pandemic-management policies. And so it has made the data as inaccessible as possible, and has tried its best to obfuscate issues. It is supported in this endeavour by a bunch of “modellers”, “scientists”, bureaucrats and an enormous propaganda system.

But even if this works for a while, this cannot work forever. There must be accountability. And hopefully the disastrous implications of “administration by masterstroke” — which we have had for a while now — will become clear to more people sooner rather than later.

Recent popular media coverage of black-hole information

Updated 4 April 2022

This is a post about the recent popular media coverage of the black hole information paradox. It is a post that I would have preferred not to make. However, I care about public outreach of science and I think that when scientists engage in outreach, they have some responsibilities. These include not misleading people, not making overblown claims, and not claiming credit for the work of others.

I understand that outreach is difficult, and it is sometimes difficult to avoid oversimplifying issues. But, in the recent stories, I see absolutely no effort to uphold these principles. Given this, I think it is important for other scientists to call this out.

Second, I think this incident provides some interesting insights into how the media operates. Some of the media organizations involved in promoting this story — the BBC, the Guardian, Newsweek and others — claim to be the source of “trusted news”. The story I am about to relate below might help to evaluate this claim.

๐’๐œ๐ข๐ž๐ง๐ญ๐ข๐Ÿ๐ข๐œ ๐›๐š๐œ๐ค๐ ๐ซ๐จ๐ฎ๐ง๐

In October last year, Calmet et al. published a paper arguing for the failure of the no-hair theorem due to quantum effects. The result is not new: it has been known to those who think about quantum aspects of black holes for several years. For instance, see this review I wrote in 2020: https://arxiv.org/pdf/2012.05770.pdf where I stated “if one attempts to use the classical [no-hair] theorem, unchanged, in quantum mechanics, then the theorem is clearly wrong.”

Calmet et al. used different techniques to study the field of two spherically symetric balls of matter and showed that this depends on more than the mass. The results of Calmet et al. do not directly address the information paradox. As Daniel Harlow emphasized in a recent discussion, just knowing the energy cannot even be used to distinguish between pure and mixed states (eg. a|E_1> + b |E_2> cannot be distinguished from |a|^2 |E_1><|E_1| + |b|^2 |E_2><E_2|).

To be clear: it has been my position for a few years (which not everyone agrees with) that the information paradox can be resolved by replacing the no-hair theorem by a principle of holography of information. This is the result, which we have developed with several collaborators that, in an appropriate UV-completion of gravity, all the information inside the black hole is available outside, which is very different from the no-hair theorem.

But the results of Calmet et al. do not establish such a principle and should not be conflated with our results. They only establish a more-limited result: that some information is available outside.

To summarize: this paper is a reasonable incremental advance that provides a supporting calculation for an existing perspective. The result is not unexpected, and was known earlier, although the authors developed new techniques that are of interest.

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A couple of weeks ago, the University of Sussex, which is the home institution for two of the authors of the paper above, decided to go on a publicity blitz. The blitz was timed with the journal-publication of this paper and a companion paper (in PLB and PRL). Journal publication means very little in hep-th, but journalists don’t know this and think of “peer-review” as some mystical magical process.

I first learned of the U. Sussex publicity stunt when I was contacted by the BBC asking for comments on a study “which claims to resolve the Hawking paradox.” I was quite puzzled about what the BBC was talking about, but after some back and forth, I was given a copy of the actual press-release from U. Sussex and the paper from October 21.

The press release skipped over the state of the scientific field and claimed a dramatic result well in excess of what was claimed in the paper itself.

I tried to be positive about the paper. But I kept pointing out to the BBC that this work didn’t represent a fundamentally new perspective. However, the BBC kept pressing me for a quote that would fit their story. The final quote they used came from this exchange:

====== BBC: Does this resolve the information paradox?

Reply:

I think this insight — the failure of the no hair theorem — does resolve the information paradox as it was formulated by Hawking.

However, it would be demonstrably incorrect to attribute this insight to the recent work of Calmet et al.

I think the correct and verifiable statement is that “in the past few years, it has been recognized that the no hair theorem fails due to quantum effects and this resolves Hawking’s paradox.”

The recent paper provides additional evidence for the failure of the no-hair theorem when quantum mechanical effects are included.

=====

Some word of this got back to the authors. So, a day later, I received a nice email from one of the (non-Sussex) authors who explained that I shouldn’t take the U. Sussex PR department too seriously since they were just “doing their job” and getting the science right was “only secondary” in this job. I largely forgot about the matter, and assumed that now that the BBC had been pointed in the right direction, they would ignore the U. Sussex PR machine, do their own research and write some kind of a balanced popular science article on a better understanding of quantum information in quantum gravity.

How naive! A few days later, the following BBC story appeared. You can read it for yourself here and form an opinion. Note also the truncaton of my quote. (more on this below). https://www.bbc.com/news/science-environment-60708711

The U. Sussex pitch to BBC offered it an “exclusive”. But similar stories soon appeared in the Guardian, the Independent, the Daily Mail and several other British media outlets. From there, it was picked up by media outlets across the world. Even our own News 18 in Hindi. A Google news search will reveal hundreds of similar stories.

As far as I can see, the authors have made no attempt to correct this overblown coverage.

๐€ ๐Ÿ๐ž๐ฐ ๐ช๐ฎ๐ž๐ฌ๐ญ๐ข๐จ๐ง๐ฌ ๐Ÿ๐จ๐ซ ๐ฌ๐œ๐ข๐ž๐ง๐œ๐ž ๐ฃ๐จ๐ฎ๐ซ๐ง๐š๐ฅ๐ข๐ฌ๐ญ๐ฌ:

  1. A uniform characteristic of all these stories is that they almost entirely conform to the University press release and at most have a single external quote for form. How do science journalists make an assessment of the quality or importance of the work? For instance, the BBC decided the Calmet et al. paper was “revolutionary”. But I am the only external scientist quoted in the story. My opinion was the one given above. So how did the BBC reach this conclusion? Do they have in-house experts on quantum aspects of black holes who assessed the paper for them?

Same question for the Guardian — the supposedly sober representative of establishment British journalism. It decided that this might possibly represent a “momentous advance.” (See: https://www.theguardian.com/science/2022/mar/17/quantum-hair-could-resolve-stephen-hawking-black-hole-paradox-say-scientists) ) But the sole external scientist quoted is Toby Wiseman who correctly expressed skepticism about the paper. So how did the Guardian arrive at this assessment?

Some news organizations, like the Daily Mail decided to dispense with the external expert entirely! So do they usually believe whatever a PR agency tells them, without even bothering to ask even one neutral knowledgeable person?

I think this is important for reasons that go beyond this story. Why should these news organizations be trusted to perform “fact checks” and weed out “fake news” that they keep complaining about, if this is how they do their job in relatively objective areas like physics.

As far as I can see, they decided to simply blindly trust the University press release because the University was British. (I bet they wouldn’t have published anything if more established researchers on the information paradox geographically based outside Western Europe or the United States had sent this story to them.)

Given this touching faith of the British mainstream media in British institutions, is it surprising that they swallowed — hook, line and sinker — stories about WMDs when the British government told them about it?

Another problem is that these news outlets have more credibility than they deserve. So once they publish something, news outlets in other parts of the world follow their lead. Obviously, this is a serious and broader problem.

  1. Are the science journalists at these organizations trained in doing basic literature searches? As of 25 March, Inspire-HEP shows that this paper has zero published citations, once self-citations are excluded.

To be clear: citations are a very flawed measure and I believe they are influenced by all sorts of non-scientific factors. They largely reflect networks of scientists citing each other and so it may well happen that papers with few citations are important.

But, even then, didn’t “zero citations in five months” send up some red flags for journalists? It means that the paper hasn’t created any immediate splash in the community that works on the subject. Shouldn’t this have encouraged some due diligence?

  1. Are science journalists at these organizations trained to check if scientists are claiming novelty where it doesn’t exist? A simple Google scholar search would have revealed that failure of the no-hair theorem and its implications for the information paradox has been investigated in print well before this paper. For instance a Google scholar search with keywords “no hair theorem, quantum mechanics, information paradox” will throw up the review above. So even a small amount of research should have been sufficient, even for non-specialists to recognize that the perspective of Calmet et al. is not fundamentally new.

  2. Do science journalists who write such stories even bother to read the paper they are reporting on and see if it conforms to the news release? In this case, the scientific paper itself doesn’t make the claims that the press-release does. Are the journalists aware of the following two-step possibility: (a) scientists write a paper and get it published (b) they issue a press-release that notionally refers to the paper, but actually has little to do with the contents of the paper.

๐€ ๐ช๐ฎ๐ž๐ฌ๐ญ๐ข๐จ๐ง ๐Ÿ๐จ๐ซ ๐จ๐ญ๐ก๐ž๐ซ ๐ฌ๐œ๐ข๐ž๐ง๐ญ๐ข๐ฌ๐ญ๐ฌ

Obviously, experts in the subject are uniformly amused at these articles. Within this small community, these news articles don’t do the authors any good. But we are fooling ourselves if we think that these stories don’t matter. They are read by our colleagues in adjacent offices who work in related areas. They are read by undergraduate and graduate students who make career-decisions based on them. So what should be done to counter this?

Many of us are wary of aggressive publicity of this kind since it is hard to do good outreach without misleading people. But this just leaves the door open to disigenuous media-blitzes of the kind above that do a significant amount of harm.

The Sci-Hub Case and the Future of Scientific Publishing

As many of you know, some time back Elsevier, Wiley and the American Chemical Society filed a suit against Sci-Hub in the Delhi High Court. A group of scientists, of which I am a part, filed an intervention petition in the case. We requested the court to examine the public interest involved in the issue. (See here for more details: https://indianexpress.com/article/cities/delhi/delhi-hc-to-hear-academicians-in-case-against-open-access-sites-7136229/)

This article provides some perspective and an update on the case. I tried to mention the Scipost model and briefly point out how — even though the commercial publication model makes no sense and journals add little to no value to a paper — the model persists because a subset of the academic community benefits from the current system.

https://restofworld.org/2022/sci-hub-trial-india/

PI Colloquium: Split Property and the Information Paradox

A colloquium I gave at the Perimeter Institute a few days ago. The idea was to target a broad theoretical physics audience and so much of it is relatively non-technical. The abstract below is hopefully self explanatory.

https://pirsa.org/21110026

In an ordinary quantum field theory, the “split property” implies that the state of the system can be specified independently on a bounded subregion of a Cauchy slice and its complement. This property does not hold for theories of gravity, where observables near the boundary of the Cauchy slice uniquely fix the state on the entire slice. The original formulation of the information paradox explicitly assumed the split property and we follow this assumption to isolate the precise error in Hawking’s argument. A similar assumption also underpins the monogamy paradox of Mathur and AMPS. Finally the same assumption is used to support the common idea that the entanglement entropy of the region outside a black hole should follow a Page curve. It is for this reason that computations of the Page curve have been performed only in nonstandard theories of gravity, which include a non-gravitational bath and massive gravitons. The fine-grained entropy at future null infinity does not obey a Page curve for an evaporating black hole in standard theories of gravity but we discuss possibilities for coarse graining that might lead to a Page curve in such cases.

Failure of the Split Property in Gravity

The CQG journal is bringing out a special issue on the recent developments on the Page curve and the editors invited me to contribute something. So I took the excuse to write a “perspective essay” on the topic that appears on the arXiv today: https://arxiv.org/abs/2110.05470

The essay focuses on an incorrect assumption that plagues many discussions of black-hole information. The assumption, loosely speaking, is that the Hilbert space in gravity should factorize the way it does in QFT and so one can specify the state of a system independently inside and outside a bounded region.

Of course, it is not hard to see why this is appealing. The assumption holds in nongravitational field theories. It even has a nice formal name: “the split property”. And, in general relativity, one can find solutions that differ inside a bounded region and coincide outside. But this assumption fails when both quantum mechanical and gravitational effects are important. Instead theories of quantum gravity obey a “principle of holography of information” … once all observables outside a bounded region have been specified, the state inside the bounded region is completely fixed.

One immediate objection is: “we live in a world where gravity is presumably quantized, but we make local operations all the time.” Of course, even in gravity one can construct approximately local operators if one neglects effects suppressed by (typical-energy scale/Planck scale). This ratio is negligible in everyday life, and so our experience is well described by such approximately local operators. But if one starts asking fine-grained questions about the entanglement entropy in a gravitational theory then the fact that these operators are only approximately local and not exactly local becomes important.

This issue is definitely important for questions of black-hole information since the typical energy scale is the Hawking temperature and (Hawking temperature/planck scale) is just the inverse of the black-hole entropy. Therefore, if one tries to take the Planck scale to infinity to get rid of these unusual gravitational effects this throws out the baby with the bath water: the entropy diverges and there is no meaningful question left to ask about black hole information.

For this reason, it is impossible to ignore the unusual localization of quantum information in quantum gravity for questions of black-hole information. If one insists on taking intuition from local QFT/classical GR seriously, this often leads to a paradox.

People sometimes ask: “where is the mistake in Hawking’s argument for information loss?” The mistake is that Hawking assumed factorization of the Hilbert space up to the constraints of the no-hair theorem. The assumption is quite explicit in Hawking’s paper, and I even included a quote from the specific paragraph in the original paper to point out precisely where the error was made.

The same incorrect assumption of factorization/locality led to the monogamy paradox of Mathur, which was later revived by AMPS.

And the same incorrect assumption underlies the idea that the entropy of black-hole radiation should follow a Page curve.

In fact, it is because this assumption fails in standard gravity that, in the recent literature, the Page curve has only been computed in theories with a nongravitational bath and massive gravitons that do not obey the Gauss law. These computations are nice, but these models are very different from standard theories of gravity and it is not clear what these computations teach us about realistic black holes.

So the bottom line of the essay is: “the reason for studying the black-hole information paradox is that it teaches us about new physical effects in gravity. As such, one of the lessons that the paradox teaches us is that gravity localizes information unusually. This is a striking effect that persists in the low-energy theory.

A computation of the Page curve is not necessary to resolve the information paradox and, historically, this idea was based on a flawed physical analysis. Although it is possible to modify the system of an evaporating black hole in a standard theory of gravity so as to force a Page curve upon it, this tends to obscure the interesting physics that we learn from the paradox.”