this was 2016

The diphoton excess at 750 GeV turned out to be a statistical fluke after all. The first hint hat it was not a real signal was the lack of excess dijet events at that energy.

The good news of 2016 was that advanced LIGO announced the detection of gravitational waves and the era of gravitational wave astronomy finally began.

In business news, the oil price finally bottomed at 26.66 - too low and too late for several US oil companies. A wave of bankruptcies triggered major losses in corporate bond markets and many market observers blamed the Fed and previous quantitative easing programs for the misallocation of capital. But the Keynesian view prevailed and the Fed abandoned its rate hiking program and instead initiated QE4 and QE5.

However, the new QE programs came too late to rescue the stock market and political observers considered the market turmoil a major reason Hillary Clinton lost the election to Donald Trump, who convinced voters that he will make the stock market great again. Hillary's surprise announcement that she finally filed for divorce from Bill was not enough to turn her campaign around.

In other news, season 2 of Better Call Saul was a great success as expected, but most Hollywood movies in 2016 were disappointing - also as expected.

Merry Christmas

In case the holidays are becoming too boring at some point, I have a simple game for you and a 2nd player:
You need a round (i.e circle) or rectangular table and lots of coins, all of the same size. Now you take turns placing one coin after another on the table. The coins cannot be moved once they are placed and they cannot touch each other. The first player who does not find enough space to place another coin shall lose this game.
Now make sure that you are the first to place a coin, because then there is a simple winning strategy.
But what is this strategy?

via Der Spiegel

... in other news ...

... the LHC may have generated particles at 750 GeV of a new kind, beyond the standard model. Assuming that this is real, the obvious question is how to explain it; Jester examined a simple toy model borrowed from the standard model, while Lubos reported on more interesting explanations, e.g. a sgoldstino or a radion.

Meanwhile, Peter Woit emphasized that the latest LHC run has further pushed up limits on superpartner masses and the probability that susy will be discovered with the LHC is significantly lower now.

Away from the LHC it might be possible to test (some ideas about) quantum gravity with heavy quantum objects, as reported by Sabine Hossenfelder.

Last, but not least, it turned out (already a year ago) that the spectral gap problem, studied by solid state physicists, is undecidable if the Hamiltonian is complicated enough; Scott has more about it .

the universe and me

I have argued many times before that the many worlds interpretation does not really work. It seems that Stephen Hsu came to the same conclusion. In the comments to his blog post Lubos explains (once again) why Copenhagen is the only valid way to use quantum theory - just like string theory is the only valid way to think about everything.

I agree to a large extent with Lubos, because the split between observer and quantum world seems rather natural to me. I am always absolutely certain of my state, but apparently have to use quantum theory to describe everything else.
The natural endpoint of Lubos' argument, that there just is no (classical) reality except the observer's observations, is solipsism.

And this really "works well" as a consistent understanding of quantum theory in most cases, except for one issue: The solipsist cannot explain where I came from, just as the Copenhageners are puzzled where those observers actually come from.
The usual story of sex and babies does not work for the solipsist, because mama and papa are only images of my imagination. If I die the world ends, so where did it come from? (*)
If the Copenhagener agrees that there were no observers present at the big bang, then where do they and the universe come from?

Historically, cosmology and quantum gravity were the main reason deWitt, Hawking et al. became interested in the many worlds interpretation, but the rest of us perhaps just needs to get used to the fact that I just don't know everything.

(*) I should add that it is certainly possible that other worlds exist, some similar to mine and some very different. Obviously, I cannot use the experience of my world to assign probabilities to that; there is no valid measure for such a many worlds hypothesis.


I was not a fan of ABBA as a kid and considered their songs disco kitch. My pop music heroes at the time, from David Bowie to Frank Zappa, had a different approach.
But in recent years I began to appreciate how well-crafted some of the ABBA songs are and the musicians in the background had a lot to do with that; some consider e.g. bassist Rutger Gunnarsson as Europe's answer to James Jamerson. There is only this one video clip of Rutger on YouTube and some covers of his bass lines.
He passed away in April.

ps: One reason to re-activate this blog was to post a comment to my entry about asymptotic safety which OmarZ has sent by email.

But the timing is not completely random; I needed to remind myself that there is so much in this world, from Rutger's bass lines to the quest for quantum gravity, that is infinitely more important than the violence of some stupid assholes.

They found water ...

... but are there crabs on Mars?

You know I'm out of stuff to blog if I link to RT, but they point to the original NASA image and the crab seems to be there.

Mona Lisa's real secret ...

... is not her smile, but the alien in between her and her mirror image.

via an unknown conspiracy theorist


"We story ourselves and we are our stories. There’s a remarkably robust consensus about this claim, not only in the humanities but also in psychotherapy.
I think it’s false – false that everyone stories themselves, and false that it’s always a good thing. These are not universal human truths – even when we confine our attention to human beings who count as psychologically normal, as I will here.
There’s an experimentally well-attested distinction between human beings who have what he calls the ‘emotion of authorship’ with respect to their thoughts, and those who, like myself, have no such emotion, and feel that their thoughts are things that just happen."

After debating the "hard problem" of consciousness for many years with different people in different places, I came to the conclusion that the conscious experience of us human beings is probably much more different than commonly assumed (after all we have no way of directly comparing them). There are many hints, e.g. the fact that "tastes differ" in music and art. But if I enjoy Gesualdo and you don't, it must mean that our conscious experience is very different while we listen to moro lasso.
If it is obvious to me that the reality of qualia cannot be doubted and you think there is nothing even there to discuss, it is another strong hint that our conscious experience is actually quite different. Perhaps we experience colors with different intensity (but what exactly would that mean?).
And the way I read the article linked above, even our perception of time may not be the same.
It seems to me that brains in general are much more flexible than one would think (with one of them); but of course, I am not my brain - something that is perfectly obvious to me.

for the world is full of trickery

How do you know that this text, found on walls and on the interwebs, ...

... was not written in 1692 - without consulting Google or your knowledge of Old English grammar?

twenty years ago

If you ever watched this video, you found it very likely in the same place I did ...

new horizons


Pluto may not be a planet, but it does have a big heart ...

added later: Pluto and Charon. And Hydra.

Descartes and I

I made a similar argument as a comment on Scott's blog. Surprisingly, not everybody believed it 8-).
But I think my responses were not that bad [1, 2, 3].
The following is a summary, in case you do not want to click through those comments:

I cannot doubt that I am, however I can doubt that my brain (or any other computational device) exists.
It follows that I cannot be my brain.

Descartes’ argument is really just two statements:
1) There is a function D(x) equal to my doubt about x. Let’s say D=0 means I cannot doubt x and D>0 means I can have doubts or actually have doubts.
2) from D(I) =/= D(B) it follows that I =/= B.

There is an important issue with 1), because my doubts D(x), in general, change over time. However, Descartes’ argument is that such a change in doubt is not possible for I and B: I cannot doubt that I am, but there will always be some doubt about B.

But let us assume you can convince me that I = B, in other words I am my brain. Now let me imagine a hypothetical supercomputer S in the future, which is capable of simulating human brains and in particular exactly emulates my brain B.
Will you also try to convince me that I = S , although it is clear that B is not S?

Notice that this hypothetical supercomputer S is constructed so that every argument b1, b2, … in favor of I = B has an equivalent argument s1, s2, … in favor of I = S.
The only way to avoid a contradiction (I=B and I=S but B is not S) is to argue that S does not really exist, it is only imagined.
But this is exactly Descartes' argument: We reject I = S because we have doubts that S may exist.

added later: After some more back and forth I summarized my argument in this final comment.

asymptotic safety not so safe?

A bit more than a week ago, Ethan wrote a pop. sci. piece about quantum gravity and explained why he thinks the asymptotic safety scenario is more convincing to him than string theory.
Obviously, Lubos had to respond in his trademark style, but he also linked to an old blog post of Jacques, who argued in 2008 that "the first nontrivial test of the asymptotic safety proposal" has yet to be calculated.

I used this opportunity to post a comment there to ask if somebody had performed this non-trivial calculation by now, seven years later (*). Jacques actually responded that "the situation looks considerably worse to me than it did at the time"; the reason being that all of those calculations break BRST invariance. (I recommend to push the 'view chronologically' button if you want to read the latest comments.)

I wonder what is going on in theoretical physics nowadays - is this just another breakdown of the peer review system or something worse?
I assume Reuter et al. have their arguments to pursue a line of research which Jacques et al. thinks is "completely unreliable". But it seems the field is falling apart into different tribes, strings, a.s., lqg, cdt, etc., who no longer discuss and argue with each other and gave up on the basic notion of right vs wrong some time ago.

I think if this continues for another seven years it can only get worse and to me this is all very sad.

(*) As far as I am aware the answer is no.

added later: Jacques wrote a new blog post about his problems with asymptotic safety for quantum gravity.

added much later: I wrote another short entry about this a while later.

the emerald ash borer's mom

I really enjoyed this review of Steven Weinberg's book.
Philip Ball's was a little less positive.

The 1st link comes via Lee's comment on another blog. Full disclosure: I did not read the book.

the effectiveness of unreasonable math

Scott asked if there is something mysterious about math and, naturally, in the comments "the unreasonable effectiveness of math" came up; i.e. "why the structures that mathematicians found to be important for their own internal reasons, so often turn out to be the same structures that are important for physics". I wrote the following in response.

One should keep in mind that “the unreasonable effectiveness of math” is possible because the weirdness (e.g. the Banach-Tarski paradox) can be contained and e.g. Goedel’s result does not show up (but it could have, e.g. sums over all possible manifolds in 4d quantum gravity).
But one should also keep in mind that large parts of e.g. the standard model are not even based on well-defined (axiomatic) math, rather a patchwork of “physicist’s math” and the real mystery is why this works.

In other words, the real mystery is "the effectiveness of unreasonable math", an idea which goes back to Vaihinger and his philosophy of "as if".

identity crisis

Obviously, equations are an important feature of mathematics, but there is a problem:
"identity, an objector may urge, cannot be anything at all: two terms plainly are not identical, and one term cannot be, for what is it identical with?" as Bertrand Russell wrote.

This quote is from a blog post of John Baez, which I found fascinating because it exactly reflects my own worries about this question when I was a kid. Of course, then nobody was willing to seriously discuss this with me and it was the first time that I had to conclude that adults are less smart than I initially thought.
A similar problem was caused by my observation that one cannot make valid statements about non-existent things, e.g. the sentence "pink unicorns do not exist" has no meaning, because by definition there is nothing it could be about.
I was convinced for a while that the two problems are related but I am not so sure about this anymore. (*)

I really do regret that the internet did not exist yet when I was a kid, because it would have helped me to refine my worries tremendously (x) and e.g. think about the 'other worlds strategy' earlier (btw I discussed one problem with the idea of other worlds here). On the other hand, I am glad, for obvious reasons, that it did not exist then.
Of course, writing about a non-existent internet is problematic, so instead let me end this blog post with a link to a rather short proof of the famous equation 1+1=2, a proposition which is occasionally useful.

(*) We leave the question whether I really am (or was) the same person as I was (or am?) as a child for another time(!).
However, then I was convinced that if n is a non-existent thing, e.g. the integer n which solves the equation n*n=7, it is not necessarily true that n=n and therefore the concept of mathematical identities is problematic because of non-existent things. But I cannot be sure that I remember this argument from my childhood correctly.

(x) E.g. with a link to Black's symmetric universe.
added later: If you followed this link, then perhaps you already saw also Rene Descartes' argument about human identity: I cannot doubt that I am, however I can doubt that my body (including my brain) exists; it follows that I am not (just) my body.
This conclusion, approximately 350 years before The Matrix, about the mind-body problem was also the first important contribution to the Copenhagen interpretation imho.

the sound of silence

Now that we all have solved the puzzle from Singapore (or at least read the solution), it is time to think about another one; fortunately it is much easier.

Your boss wants to fire two of three employees, unfortunately you are one of them, and only keep the smartest. This is her challenge: There are 2 black hats and 3 white ones. You three are blindfolded and one hat placed on each of your heads (the two unused hats discarded). After the blindfolds are removed you cannot see your own hat, only the other two. The first employee to figure out the color of his own hat keeps the job.
After the blindfolds are removed you see that the other two guys have white hats. There is an awkward moment of silence and that silence in fact tells you the color of your hat.
What is it?


This parking lot seems to use a weird numbering scheme.
..., 16, 06, 68, 88, ?, 98, ...
What do you think is the number under the car?

via: Spiegel Online


1969: Astrounauts walking on the Moon.
1976: Supersonic commercial flights.
1980: Hawker Harrier jump jet.

None of the above technologies is available today.
The Space Shuttle is in a museum and NASA is slowly developing a new launch vehicle to transport humans into space - to regain the capabilities of the 1960s several years from now.
Supersonic commercial flights are not even available to very wealthy people.
The F-35 fighter jet was supposed to implement some capabilities of the jump jet, but is becoming a billion dollar debacle instead.
What happened? Why did progress in aerospace not only stall but actually reverse?
A few months ago an Antares rocket exploded, probably due to malfunctioning engines. Those engines were built in Russia in the 1960s. Not developed. Built.
Yes, there is SpaceX, but as far as I can see, the capabilities of a Falcon launch vehicle are not that advanced compared to a 1960s rocket.
Perhaps leaders a la von Braun and JFK are what is missing today or maybe technology simply does not progress along a straight path, but I would really like to understand what went wrong in aerospace over the years.

no comment

I just noticed that TBFKACIP laments "the loss of smart guys like Wolfgang and Arun" as commentators on his blog.
Thanks for the flowers, but actually it is not very smart to wrestle with pigs (x) and it is also not very smart to repeat myself; but unfortunately I feel that I have to set the record straight one more time.

The link in his post points to the "wrong" comments. Yes, I did argue with TBFKACIP several times about his idiotic stance on the Israel/Palestine issue, but his tasteless remarks about Austria, Hitler and Herzel were not the reason I decided to stop commenting at his place.
This came a bit later, after one of his regular commenters wrote that "Jews are even more heavily represented in the upper echelons of Wall Street, banking, and the media.
The media circus over the murder of three Jewish teenagers in Israel perfectly reflects their distorted priorities."
This type of comment is indistinguishable from Goebbels propaganda and I pointed that out, but TBFKACIP felt the need to support the commenter and her remarks (*).

And at this point I decided that this was finally far beyond wasting my time and that I don't want any part of this.

added later: (x) Not very witty, but it is the name he chose for his blog; his choice, not mine.

(*) Just for the record of what was written (because some seem to have problems remembering the details): His response was " Insults are pretty cheap. You might want to do the actual work of seeing whether what [..] claims is actually true - and whether that's relevant even if it is true.
Those who have looked carefully at the Israel lobby in the US have concluded that it is really an alliance between what is really a pretty small minority - American Jews and the much larger group of Christian conservatives ..."

Actually I don't want "to do the actual work" of checking the truth of antisemitic nonsense and discuss the "alliance" of American Jews and Christian conservatives to better understand "the media circus over the murder of three Jewish teenagers".
And I don't want to have a discussion with people who do.


In my list of interesting events in 2015 I forgot to mention that Dawn will meet Ceres on March 6th.
It seems that xkcd has already figured out what the white spot is about.


It is not too surprising that our brains are smart enough to understand the world around us; evolution provides a reasonable explanation.
But it is surprising that we are also able to a large extent to understand the world far away from our everyday experience; from atoms down to particle physics and on the other hand astrophysics and cosmology.
There is no good explanation why we have this capability, or in other words, why the laws of physics are simple enough for us to understand them (mostly). Of course, we have to admit that some mysteries remain, we struggle somewhat with the interpretation of quantum physics, we cannot really imagine the size of the multiverse and we even struggle to understand our own consciousness.
But we do know enough math to describe the world to an extent that has no immediate (evolutionary) benefit to us humans. Why is that?
And why is it that what we find far away from our day to day experience is actually beautiful? I am not only talking about e.g. the colorful images of galaxies, but the symmetries we find in particle physics, the elegance of general relativity etc.
There is no explanation for that and there was no reason Galileo's project went as far as it did and worked so well beyond our Earth and the solar system he tried to understand (*).
Cardinal Barberini actually made the argument at the time that the physics of Galileo cannot be trusted, because why would God have created the world so that we can understand its mysteries? Yes, why indeed - I think this is a very good question.

(*) Btw I think that people who fantasize about the promises or dangers of artificial intelligence underestimate our own natural intelligence - which made the miracle of science possible.

Lucy in the Sky ...

We are already back in Nassau, but a few days ago we saw something rare during a whale watching tour in Tromsø: stratospheric clouds (supposedly of type 2, i.e. water/ice clouds).
They are quite easy to recognize due to their rainbow colors, which brings me to this question: Why are clouds in the stratosphere so colorful but the usual clouds in the troposphere just black and white?
I think I have an answer, but I would prefer to hear an opinion from readers first ...

global group therapy

You are probably already aware that Scott Aaronson wrote a comment to his blog post about Walter Lewin which got a lot of attention on twitter and the internet in general.
Now we know why his blog is called shtetl-optimized and I think we understand better some of his earlier blog posts about biting vaginas and rape (meanwhile he deleted this blog post #260).

I find his story (which included his wish to be chemically castrated) quite disturbing and the environment he grew up in must have been very unhealthy.
His confessional triggered not only criticism from professional feminists but all kinds of comments, including similar confessionals from other young men and also women; overall the whole debate is among the weirdest ones I have ever seen in our global shtetl.
Wow. Just wow.

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