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Clat Farris Naff: Mais um adepto do Demiurgo

universo inteligenteA Secular Case for Intentional Creation

By Clay Farris Naff | November 18, 2011 |  Comments21

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“Does aught befall you? It is good. It is part of the destiny of the Universe ordained for you from the beginning.”

– Marcus Aurelius, Stoic Philosopher and Emperor of Rome, in Meditations, circa 170 CE

“’He said that, did he? … Well, you can tell him from me, he’s an ass!”

– Bertie Wooster, fictional P.G. Wodehouse character, in The Mating Season, 1949

People have been arguing about the fundamental nature of existence since, well, since people existed. Having lost exclusive claim to tools, culture, and self, one of the few remaining distinctions of our species is that we can argue about the fundamental nature of existence.

There are, however, two sets of people who want to shut the argument down. One is the drearily familiar set of religious fundamentalists. The other is the shiny new set of atheists who claim that science demonstrates beyond reasonable doubt that our existence is accidental, purposeless, and doomed. My intent is to show that both are wrong.

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Explosões cósmicas, vida no Universo e a constante cosmológica

Cosmic Explosions, Life in the Universe, and the Cosmological Constant

Tsvi Piran, Raul Jimenez, Antonio J. Cuesta, Fergus Simpson, and Licia Verde
Phys. Rev. Lett. 116, 081301 – Published 23 February 2016
ABSTRACT

Gamma-ray bursts (GRBs) are copious sources of gamma rays whose interaction with a planetary atmosphere can pose a threat to complex life. Using recent determinations of their rate and probability of causing massive extinction, we explore what types of universes are most likely to harbor advanced forms of life. We use cosmological N-body simulations to determine at what time and for what value of the cosmological constant (Λ) the chances of life being unaffected by cosmic explosions are maximized. Life survival to GRBs favors Lambda-dominated universes. Within a cold dark matter model with a cosmological constant, the likelihood of life survival to GRBs is governed by the value of Λ and the age of the Universe. We find that we seem to live in a favorable point in this parameter space that minimizes the exposure to cosmic explosions, yet maximizes the number of main sequence (hydrogen-burning) stars around which advanced life forms can exist.

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A TEORIA QUE NÃO MORRERIA

LIVRO A TEORIA QUE NAO MORRERIA

SINOPSE

Esta é a história de como uma lei da matemática teve seu destino entrelaçado com os sigilos da Segunda Guerra Mundial e da Guerra Fria. De um teorema em busca de um computador e de um software. De um método que – atualizado por outsiders da física, da ciência da computação e da inteligência artificial – foi adotado quase do dia para a noite porque, de repente, funcionou. O teorema que um dia foi considerado “a pedra de crack da estatística… sedutora, viciante e basicamente destrutiva”, hoje, em um novo tipo de paradigma deslocado para um mundo pragmático, propicia o recrutamento de bayesianos para as mais inovadoras companhias.

DADOS DO PRODUTO

título: A TEORIA QUE NAO MORRERIA
isbn: 9788527310345
idioma: Português
encadernação: Brochura
formato: 14 x 21
páginas: 480
ano de edição: 2015
edição:

 

Um paper importante sobre evidências do Multiverso

Spectral Variations of the Sky: Constraints on Alternate Universes

We analyze the spectral properties of masked, foreground-cleaned Planck maps between 100 and 545 GHz. We find convincing evidence for residual excess emission in the 143 GHz band in the direction of CMB cold spots which is well correlated with corresponding emission at 100 GHz. The median residual 100 to 143 GHz intensity ratio is consistent with Galactic synchrotron emission with a Iνν0.69 spectrum. In addition, we find a small set of ~2-4 degree regions which show anomalously strong 143 GHz emission but no correspondingly strong emission at either 100 or 217 GHz. The signal to noise of this 143 GHz residual emission is at the 6σ level. We assess different mechanisms for this residual emission and conclude that although there is a 30\% probability that noise fluctuations may cause foregrounds to fall within 3σ of the excess, it could also possibly be due to the collision of our Universe with an alternate Universe whose baryon to photon ratio is a factor of 65 larger than ours. The dominant systematic source of uncertainty in the conclusion remains residual foreground emission from the Galaxy which can be mitigated through narrow band spectral mapping in the millimeter bands by future missions and through deeper observations at 100 and 217 GHz.

Comments: 25 pages, 8 figures (6 color, 2 B&W), Submitted to ApJ, comments welcome
Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
Cite as: arXiv:1510.00126 [astro-ph.CO]
(or arXiv:1510.00126v1 [astro-ph.CO] for this version)

New Scientist THIS WEEK 28 October 2015

Mystery bright spots could be first glimpse of another universe
Light given off by hydrogen shortly after the big bang has left some unexplained bright patches in space. Are they evidence of bumping into another universe?

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Livro Projeto Mulah de Tróia levou 25 anos para ser publicado

Sim, se a qualidade literária se mede pelos anos que o autor levou para burilar o texto, então este é um candidato ao Prêmio Argos…  Para comprar, clique aqui.

PMT2

  • Jenitez nos brinda com uma pérola da Ficção Científica de humor, uma bem dosada mistura de Umberto Eco e Planeta Diário: uma estória recheada de referências internas, coerentes do início ao fim e com um estilo impecável. Com descrições claras e pouca adjetivação, além de uma ironia finíssima, o autor brinca com a física, a cultura pop e a literatura, com um texto de uma clareza e um bom gosto tão grandes que mesmo um leigo em FC pode entender e gostar. Um trabalho bem escrito não pode ser analisado a fundo, basta que apenas seja lido. E esta estória precisa ser lida. Fábio Fernandes

The exoplanets analogy to the Multiverse

kepler-planet-candidatesPrecisa dar uma melhorada. Pretendo enviar para o International Journal of Astrobiology.

The exoplanets analogy to the Multiverse

The idea of a Mutiverse is controversial, although it is a natural possible solution to particle physics and cosmological fine-tuning problems (FTPs). Here I explore the analogy between the Multiverse proposal and the proposal that there exist an infinite number of stellar systems with planets in a flat Universe, the Multiplanetverse. Although the measure problem is present in this scenario, the idea of a Multiplanetverse has predictive power, even in the absence of direct evidence for exoplanets that appeared since the 90s. We argue that the fine-tuning of Earth to life (and not only the fine-tuning of life to Earth) could predict with certainty the existence of exoplanets decades or even centuries before that direct evidence. Several other predictions can be made by studying only the Earth and the Sun, without any information about stars. The analogy also shows that theories that defend that the Earth is the unique existing planet and that, at the same time, is fine-tuned to life by pure chance (or pure physical necessity from a parameter free Theory of Everything) are misguided, and alike opinions about our Universe are similarly delusional.

Comments: 9 pages, 1 figure
Subjects: General Physics (physics.gen-ph); History and Philosophy of Physics (physics.hist-ph)
Cite as: arXiv:1506.08060 [physics.gen-ph]
(or arXiv:1506.08060v1 [physics.gen-ph] for this version)

Submission history

From: Osame Kinouchi [view email]
[v1] Tue, 16 Jun 2015 22:42:12 GMT (566kb)

 

Artigo aceito pelo PRE

Aceito pelo Physical Review E.

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Nonsynchronous updating in the multiverse of cellular automata

In this paper we study updating effects on cellular automata rule space. We consider a subset of 6144 order-3 automata from the space of 262144 bi-dimensional outer-totalistic rules. We compare synchronous to asynchronous and sequential updatings. Focusing on two automata, we discuss how update changes destroy typical structures of these rules. Besides, we show that the first-order phase-transition in the multiverse of synchronous cellular automata, revealed with the use of a recently introduced control parameter, seems to be robust not only to changes in update schema but also to different initial densities.

Subjects: Cellular Automata and Lattice Gases (nlin.CG); Statistical Mechanics (cond-mat.stat-mech)
Cite as: arXiv:1503.01350 [nlin.CG]
(or arXiv:1503.01350v1 [nlin.CG] for this version)

 

Multiverso com ferramenta matemática preditiva

mUltiverseMe parece que a ideia de Multiverso está ficando cada vez mais relevante e preditiva. Já a ideia de explicar fine tuning no universo usando ideias físicas convencionais (simetrias etc) parece estar num beco sem saída, nenhum avanço foi obtido há décadas.

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High Energy Physics – Phenomenology

Radiative PQ Breaking and the Higgs Boson Mass

The small and negative value of the Standard Model Higgs quartic coupling at high scales can be understood in terms of anthropic selection on a landscape where large and negative values are favored: most universes have a very short-lived electroweak vacuum and typical observers are in universes close to the corresponding metastability boundary. We provide a simple example of such a landscape with a Peccei-Quinn symmetry breaking scale generated through dimensional transmutation and supersymmetry softly broken at an intermediate scale. Large and negative contributions to the Higgs quartic are typically generated on integrating out the saxion field. Cancellations among these contributions are forced by the anthropic requirement of a sufficiently long-lived electroweak vacuum, determining the multiverse distribution for the Higgs quartic in a similar way to that of the cosmological constant. This leads to a statistical prediction of the Higgs boson mass that, for a wide range of parameters, yields the observed value within the 1σ statistical uncertainty of 5 GeV originating from the multiverse distribution. The strong CP problem is solved and single-component axion dark matter is predicted, with an abundance that can be understood from environmental selection. A more general setting for the Higgs mass prediction is discussed.

Comments: 30 pages, 10 figures
Subjects: High Energy Physics – Phenomenology (hep-ph)
Cite as: arXiv:1502.06963 [hep-ph]
(or arXiv:1502.06963v1 [hep-ph] for this version)

Multiverso e Ajuste Fino: o que ler?

mUltiverseCut and paste do ótimo post de Luke Barnes: 

What to Read: The Fine-Tuning of the Universe for Intelligent life

I’ve spent a lot of time critiquing articles on the fine-tuning of the universe for intelligent life. I should really give the other side of the story. Below are some of the good ones, ranging from popular level books to technical articles. I’ve given my recommendations for popular cosmology books here.

Books – Popular-level

  • Just Six Numbers, Martin Rees – Highly recommended, with a strong focus on cosmology and astrophysics, as you’d expect from the Astronomer Royal. Rees gives a clear exposition of modern cosmology, including inflation, and ends up giving a cogent defence of the multiverse.
  • The Goldilocks Enigma, Paul Davies – Davies is an excellent writer and has long been an important contributor to this field. His discussion of the physics is very good, and includes a description of the Higgs mechanism. When he strays into metaphysics, he is thorough and thoughtful, even when he is defending conclusions that I don’t agree with.
  • The Cosmic Landscape: String Theory and the Illusion of Intelligent Design, Leonard Susskind – I’ve reviewed this book in detail in a previous blog posts. Highly recommended. I can also recommend his many lectures on YouTube.
  • Constants of Nature, John Barrow – A discussion of the physics behind the constants of nature. An excellent presentation of modern physics, cosmology and their relationship to mathematics, which includes a chapter on the anthropic principle and a discussion of the multiverse.
  • Cosmology: The Science of the Universe, Edward Harrison – My favouritecosmology introduction. The entire book is worth reading, not least the sections on life in the universe and the multiverse.
  • At Home in the Universe, John Wheeler – A thoughtful and wonderfully written collection of essays, some of which touch on matters anthropic.

I haven’t read Brian Greene’s book on the multiverse but I’ve read his other books and they’re excellent. Stephen Hawking discusses fine-tuning in A Brief History of Time and the Grand Design. As usual, read anything by Sean Carroll, Frank Wilczek, and Alex Vilenkin.

Books – Advanced

  • The Cosmological Anthropic Principle, Barrow and Tipler – still the standard in the field. Even if you can’t follow the equations in the middle chapters, it’s still worth a read as the discussion is quite clear. Gets a bit speculative in the final chapters, but its fairly obvious where to apply your grain of salt.
  • Universe or Multiverse (Edited by Bernard Carr) – the new standard. A great collection of papers by most of the experts in the field. Special mention goes to the papers by Weinberg, Wilczek, Aguirre, and Hogan.

Scientific Review Articles

The field of fine-tuning grew out of the so-called “Large numbers hypothesis” of Paul Dirac, which is owes a lot to Weyl and is further discussed by Eddington, Gamow and others. These discussions evolve into fine-tuning when Dicke explains them using the anthropic principle. Dicke’s method is examined and expanded in these classic papers of the field:

A number of papers, while not discussing fine-tuning, are very relevant as they discuss how the macroscopic universe depends on the values of fundamental constants. Here are a few good examples.

Here are a few good review papers, arranged in order of increasing technical level.

Technical scientific articles

Here are some of the papers that have performed detailed calculations of specific fine-tuning cases, in chronological order.

Particle Physics Parameters

Cosmology Parameters

Philosophical articles and books

  • Issues in the Philosophy of Cosmology, Ellis (2006). An excellent review of some of the philosophical issues raised by modern cosmology, including fine-tuning. See also “Philosophy of Cosmology” by Chris Smeenk.
  • Universes, John Leslie – A tremendously clear exposition of what conclusions we can and should draw from fine tuning. Leslie loves a good analogy, and his choice of illustration is almost always excellent. Another must read.

Part of the reason why the fine-tuning of the universe for life is of such interest to philosophers is that it is often used as a premise in an argument for the existence of God.  A lot of the literature on the fine-tuning argument, pro and con, misses the mark by a large margin, in my opinion. Here are three of the best expositions of this argument.

Unsurprisingly, such claims have not gone unchallenged. Here are some of the best responses.

  • Does the Universe Need God?, Sean Carroll (2012) – A good, if brief, response to the arguments above. I recently presented fine-tuning with Carroll in the audience and he gave some good comments. I wouldn’t mind seeing him give an extended response.
  • See also the books by Leonard Susskind and Alex Vilenkin (and, though I haven’t read them, Brian Greene and Stephen Hawking) for a defence of the multiverse as the correct explanation for fine-tuning.
  • Probabilities and the Fine‐Tuning Argument: a Sceptical View, McGrew, McGrew and Vestrup – A critique of the fine-tuning argument for the existence of God based on skepticism as to the applicability of probabilities to hypothetical universes. At least two of the authors are theists. See also this paper by Bradley Monton (though I don’t think that the “old evidence” problem exists for Bayesian theories of probability.)

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