Best Christmas baroque performance

No, I’m not religious at all. However, my favorite composer is Johann Sebastian Bach, specially his sacred works. In my opinion, if I had to choose a music to represent mankind, it would be his St. Matthew Passion.

There is no other musician that can be compared with Bach. (No, don’t try to convince me otherwise!).

For Christmas, my favorite performance is this: Christmas Oratorio (Weihnachtsoratorium), conducted by Nikolaus Harnoncourt, with soloists Peter Schreier (tenor, perfect), Robert Holl (bass), Concentus Musicus (tenor and bass choral) and the wonderful boy’s choral Tolzer Knabenchor.

In that performance, recorded around 1981, I call your attention for the 3 excellent boy sopranos soloists. One of them I have identified as being Allan Bergius, the one with the most “angel-like” voice, who sings the difficult and beautiful terzett “Ach, wenn wird die Zeit erscheinen?”, along with Peter Schreier and the boy alto soloist Stefan Rampf, who also has a splendid perfomance overall (being the only alto soloist in whole oratorio), given the difficulty of the cantatas and the need for a maturity that is impossible to ask for such young boys. Another boy soprano soloist (a curly-haired boy) has an incredible soprano-dramatic voice, very rich in the middle, low range, with potent high notes and great musicality, but I could not identify his name. To him, is given the lovely “echo-aria”, “Flößt, mein Heiland”, as well as the dramatic and demanding aria “Nur ein Wink von seinen Händen”. The third boy soloist is the blond, long-haired one, who I also could not identify his name– he has a very soft and small voice, but exceptional musicality, who is given the sweet duett “Herr, dein Mitleid, dein Erbarmen”, along with the bass soloist Robert Holl.

The expressiveness of Nikolaus Harnoncourt also makes this DVD a very special one.

I think I have watched this performance more than a hundred times, and I can sing all soprano parts (even other parts) from my heart. I recommend it to anyone, anywhere, anytime. But, specially, this time.

Overview of the choral.

The boy soprano with an angel voice, identified as the very young Allan Bergius. Wonderful perfomance of difficult parts.

Excellent boy soprano, dramatic and versatile voice.

Soft voiced soprano with great expressiveness and musicality.

Beautiful alto voice; complete control of all alto pieces. Identified as Stefan Rampf.

A wonderful Oratorio passage: tenor Peter Schreier with his very young (but very professional) singer colleagues in a demanding part.

For trekkies…

My favorite…

Competitive Cycle

Over at the Cosmic Variance discussion on Lisi’s TOE, the question of competition versus collaboration in science, and the existence of arrogance in many scientists in doing their professional activities has been raised.

Sure, one can be very successful making a science career being very competitive and aggressive. In fact, the system favors these characteristics. Why? Because science is made by people, and those who are more competitive and aggressive naturally tend to be more successful in climbing into key positions in the system. So the present situation in science is a somewhat closed cycle in this respect.

So yes, it is possible to do science under that scheme and be very successful. However, is it an optimum system in the long term?

I don’t think so.

Competitive and aggressive scientists probe nature under very specific motivations — that is, “how to be successful” in their careers. This may lead him/her to important discoveries and there are certainly many examples of them. But there are many fundamental and deep questions in nature that I really doubt that can be adequately advanced if you do not have a truthfully inquisitive, contemplative, genuine curious mind about nature’s deepest secrets. People with such an approach to science have learned the meaning of the words “humbleness” and “collaboration”, can also be successful, and there are certainly some examples of them, but I really think they are a minority, at least in our current epoch. The system definitely does not favor such people in science.

On purely philosophical grounds, I consider it very strange that we, supposedly intelligent people, let the situation develop into that closed cycle. The cycle can be easily explained, as I did above, but it is really a shame that we let ourselves into this. Is it not obvious that we need a healthy collaborative environment, with plenty of genuine modesty and humbleness, towards the understanding of the vastness of nature?

Aggressiveness and competitiveness can be the means to accomplish that goal, and you can follow them if they are attractive to you and to your aims in life, and indeed the achievements that may result from such a path can certainly make many satisfied. Yet, a vast sea of unknown is doomed to be hidden by construction to them, because the understanding of nature and our place in the universe are not things to be conquered (like territory and hunt were things to be conquered by our ancestors in order to survive), but things of the human intellect, that must be nurtured, grown and shared to all, with pain, persistence, reason, humility, curiosity. With our minds filled with wonder.

Update: Some technical discussions between Distler and Smolin finally appeared in the comment’s section over at CV after I wrote this post. If I find time, I’ll try to make a compilation of them in my blog.

Update: I have added my compilation in the post about Lisi’s paper.

Concurrent Events

You will find a review on Max Jammer’s new book, Concepts of Simultaneity: From Antiquity to Einstein and Beyond, in this well-written American Scientist article.

I have three other well-known books by Jammer — “Concepts of” Space, … Force, and … Mass –, but could only find time to finish the latter. It is a very erudite work, written with great care and detail. According to the reviewer, his new book misses some recent developments, but given the material covered and also considering that Jammer is such an excellent writer, I believe it will be also worth reading.

Introducing… my Brazilian ‘Tigre d’Água’ Turtles

Here they are. They are one year old now and were legally purchased from this breeder. In English they are called “D’Orbigny’s slider turtles”. This species is from southern Brazil. I’ll take better pictures when I have the opportunity.

I don’t know whether they are male/female. One can tell only when they grow older.

Here is their present aquaterrarium, in the process of being cleaned up. It is a simple process, but must be repeated often. I don’t have filters for the moment.

They enjoy to lay under the sun. They can see and hear extremely well. And I can tell you that they have different personalities.

Garrett and Smolin, to boldly go…

I should warn the reader that all that follows is a personal interpretation from a curious person that is attempting to learn new subjects. Your corrections are welcome.

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As I have previously mentioned, Garrett Lisi’s work sounds extremely interesting, and any reasonable person expects that it finds its way to a serious critical analysis before far reaching conclusions and speculations take over. There are many issues that need further work. This is what Garrett explicitly have said several times.

Lisi’s paper got attention: a relatively heavy media hype (considering perhaps the title of the paper and the fact that Lisi is not in the academia, and enjoys a different lifestyle) and inumerous discussions all over the blogosphere. Now that things appear to have calmed down (although we can still hear some fresh echoes of “Lisi’s wave”), a new paper by Smolin, citing Lisi’s work, appeared in the scene.

From a first reading of Smolin’s paper, the most interesting aspect of it (as I see it) appears to be the introduction of an extension of the Plebanski action that accepts any large group structure (containing the local Lorentz group), showing that, with a symmetry breaking mechanism, the resulting dynamics is that of a unified Einstein-Yang-Mills, plus corrections. Smolin suggests his framework could be used for building up the dynamical sector of Lisi’s proposal (by applying the group E8 in the proposed extended action), a part of Lisi’s work that has not been worked out satisfactorily. According to Smolin, it would give “a fully gauge invariant action, which has solutions which spontaneously break the symmetry and give, when expanded around, the bosonic part of Lisi’s action, plus corrections”.

Smolin also suggests techniques from LQG, more specifically, the notion of “disordered locality”, as an alternative for the description of fermions and scalars to that used by Lisi (BRST extension of the connection). That part of the paper is not sufficiently clear to me, but while I try to figure it out, I would gladly accept a clarification.

Although Smolin recognises that there are open issues in Lisi’s work, specially whether the three generations of quarks and leptons are realized in the proposed structure of the E8 group, he boldly advances Lisi’s idea into aspects that as far as I was able to follow have not emerged from the whole body of discussions elsewhere. But I guess these ideas have been exchanged privately for some time (as inferred from the acknowledgement section of both Smolin and Lisi’s paper, as well as the mentioning by Lisi in his paper that the “quantum E8 theory follows the methods of quantum field theory and loop quantum gravity — though the details await future work”).

In any case, the main idea of Smolin’s paper seems to be independent of Lisi’s proposal. That is, suppose the E8 group ends up to be the wrong route. And instead one finds another group that realises the unification. Would not Smolin’s framework be consistent enough in order to allow the study of the resulting dynamics of the “correct” group, whatever it is?

So I think we have two separate issues here. One is the validity of Lisi’s proposal first of all. The other is how far Smolin’s work is dependent on it. As I mentioned, it does not appear to be completely dependent on it. He uses Lisi’s proposal as an example of application. But I may be wrong.

In any case, it is of fundamental importance to go through all the necessary details and assumptions systematically before reaching any conclusions.

On that regard, Jacques Distler has posted twice about Lisi’s work on his blog (here and here) where he argues the impossibility of getting all three fundamental particle generations through Lisi’s embedding into the E8 group. What calls the attention is Distler’s purely mathematical argumentation involving group theory representation only.

So it seems that we have reached a very first bottleneck on Lisi’s idea, in which there appears to be concrete technical (mathematical) issues that are absolutely necessary to be cleared up before continuing. Since it is a purely mathematical issue, it is indeed a point of tension that should be released before anything else. Otherwise the whole edifice of unification through E8 symmetry seems to face an early collapse.

This is unambiguous — as far as mathematics is: is Distler right or wrong?

Is Smolin’s results dependent on Lisi’s work?

If you would like to discuss specifics of the first question, please do it here. To the second question, you are invited to go here. These posts are for technical comments only. For general or more qualitative comments, you may use the present post.

As a final remark, I wonder whether those papers are being considered for refereed publication. I think that well moderated blogs can be a remarkable arena where scientific works can be widely discussed. But at the same time they do have a limited scope. Also, the peer review system has its problems; this is well known and acknowledged. It is not clear whether the authors will submit their papers to a journal. So what are we left with?

Not every member of the scientific community, whatever the field, is connected to the blogosphere. And even if they were connected, would it be acknowledged that blogs are the place where a consensus on the validity of a scientific work is to be met? Where should they be met anyway? We live the revolution of information and communication that the internet has brought, so there is a visible change in the scientific arena of discussions. Things are not as before.

In any case, Nature is the final judge. If you have a theory that can be cleary tested, then that is what is needed at the end of the day.

Except, of course, if you have got wrong mathematics to begin with.

Update: Garrett Lisi invites a technical discussion on his paper in this thread over at PF.

Quantum Gravity Partition Functions in Three Dimensions

(Via Woit’s Blog). This is also an interesting paper by Alexander Maloney and Edward Witten: http://arxiv.org/abs/0712.0155

We consider pure three-dimensional quantum gravity with a negative cosmological constant. The sum of known contributions to the partition function from classical geometries can be computed exactly, including quantum corrections. However, the result is not physically sensible, and if the model does exist, there are some additional contributions. One possibility is that the theory may have long strings and a continuous spectrum. Another possibility is that complex geometries need to be included, possibly leading to a holomorphically factorized partition function. We analyze the subleading corrections to the Bekenstein-Hawking entropy and show that these can be correctly reproduced in such a holomorphically factorized theory. We also consider the Hawking-Page phase transition between a thermal gas and a black hole and show that it is a phase transition of Lee-Yang type, associated with a condensation of zeros in the complex temperature plane. Finally, we analyze pure three-dimensional supergravity, with similar results

Witten has written some months ago a paper in 3D quantum gravity and the monster group (see previous post here). Apparently, such ‘unphysical’ models may be (are supposed to be?) useful to learn about full quantum gravity.

The Plebanski action extended to a unification of gravity and Yang-Mills theory

(Via Physics Forums). This is the new paper by Lee Smolin: http://arxiv.org/abs/0712.0977.

We study a unification of gravity with Yang-Mills fields based on a simple extension of the Plebanski action to a Lie group G which contains the local lorentz group. The Coleman-Mandula theorem is avoided because the theory necessarily has a non-zero cosmological constant and the dynamics has no global spacetime symmetry. This may be applied to Lisi’s proposal of an E8 unified theory, giving a fully E8 invariant action. The extended form of the Plebanski action suggests a new class of spin foam models.

Notice the citation to Lisi’s recent paper.

I read Lisi’s paper and I’ll read this one. Sounds very interesting indeed, and a quite “fast link” to Lisi’s idea, that is, a connection of that idea with the LQG framework.

If you would like to discuss that paper in technical terms, I’ll be glad to host your comments here. Recall that this is a highly moderated, very high signal to noise ratio blog. Be educated.

Update: A personal view can be found here.

[English][Português] The Universe and the Solar System for Kids

[English]

Today, I had a really great experience. I was invited to give an astronomy talk to the 8 years-old kids in my son’s class.

For that I prepared a short film using iMovie. The film could be paused as I needed to explain things and the kids were able to make questions (and they did ask a lot of interesting questions!).

Also, I prepared a mini-solar system in (more or less) scale using simple material that kids can prepare themselves. Here is a picture:

This site is very useful to make a model of the solar system in scale, including the orbits. I have made a second set of the solar system including the Sun in a scale of 4cm in diameter, and we were able to lay the nano-planets (indeed, Mercury is almost nothing at that scale!) over the floor with the help of a metric tape. At about 22 meters from the Sun, Jupiter was the last one that fit into the recreational area.

Notice that I have started with the Sun, setting it to 4 cm in diameter in order to get at least Jupiter’s orbit inside the recreational area of the school. Mercury gets incredibly tiny in that scale. If you have a larger area you can try a larger value for the Sun’s diameter.

I do not recall the modeling clay type that I used. Also, I am in Brazil, so I don’t think I can help you indicating specific brands, in case you came here from elsewhere… In any case, I hope that site above helps you in setting an adequate solar system scale.

I can send you the video if you are interested, but all titles are in portuguese. Contact me by email: christinedantas*AT*yahoo.com. What follows are directions in portuguese.

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[Português]

MATERIAL EDUCATIVO SOBRE O UNIVERSO E O SISTEMA SOLAR

Criei um filme e um texto para alunos do ensino fundamental. O filme e o texto de narração estão disponíveis gratuitamente. Para adquirir o filme em alta resolução, é necessário o envio de um DVD virgem para cópia e o valor em dinheiro para postagem simples. Se houver interesse, entre em contato pelo email: christinedantas*AT*yahoo.com. Uma versão do filme em baixa resolução (para avaliação inicial) pode ser adquirido através do serviço YouSentIt (entre em contato pelo email acima). Futuramente, penso em colocar o filme no YouTube.

Você pode baixar o texto abaixo gratuitamente, sob licença Creative Commons:

O Universo e o Sistema Solar: em formato pdf para download. Este texto pode ser usado livremente, porém os direitos são reservados para Christine Córdula Dantas.

O sistema solar da figura acima foi feito em massinha de modelar simples.

Beware! A chimpanzee can beat you.

Yes, that is true. Look at this Nature article.

Chimpanzees seem to be “better at memorizing a snapshot view of their surroundings” than us. Apparently, “humans may have lost this capacity in exchange for gaining the brainpower to understand language and complex symbols”.

Well. In any case, I’d not be surprised if chimpanzees would beat some humans in some respects. Even dogs can beat humans in some respects. My own dog can beat many people I know when it comes to having a pure and kind temperament.

2 + 2 = ?

The other day my 8 year old son came with this one:

- If 2 values 1, how much is 2 + 2 ?

Of course I was busy in the kitchen and replied simply:

- 2.

- No – he said triumphantly -, it’s 1.

Of course, he was right.