Port security, worldwide, has been compromised by a forseeable, and avoidable, mistake.

That humans make mistakes is obvious. Sometimes those mistakes carry little, if any consequences. Sometimes errors can be overwhelming. If there is one current theme in our efforts to achieve nuclear security, it is that we are ”mistake prone.” What comes of these blunders…only time will tell.

Take the example of nuclear material and bomb detectors intended for use at world-wide cargo ports.

Clearly it is wise to develop technology for detecting nuclear devices which can be secreted into the country in shipping containers. It is a colossal mistake, however, to run out of a key ingredient, a raw material essential to the development of such technology, because someone forgot to make sure there was enough helium-3 to make functional the 1,300 to 1,400 machines planned to spot uranium or plutonium.

According to the New York Times on November 23, helium-3 is derived from decayed tritium, which comes from hydrogen bombs. The last time we made tritium was in 1989, when the Berlin Wall fell.  Since then, the available supply of helium-3, which detects neutrons which are given off by plutonium bombs, has diminished. While there are substitutes for the scarce ingredient, none are reported to be as effective or as discriminatory when discerning between nuclear weapons and ordinary things cargo like kitty litter and bananas.

According to the Times report, “The helium-3 problem is another symptom of the decline of nuclear technology.” Why the Department of Homeland Security did not seem to know it could not deploy all of the detection machines because of a limited amount of helium-3 is a mystery. It signals a serious mistake in planning.  According to Representative Brad Miller (D-North Carolina), “I have not heard any explanation of why this was not entirely foreseeable.”

The problem of bombs and nuclear components being ushered in with cargo containers is not new or limited to the U.S. It is a real and present danger across the globe. (See video).

The helium problem is particularly troubling. The miscalculation about how much was available could be catastrophic if a smuggled weapon or nuclear material is actually used because of the lack of detection equipment at American and foreign shipping ports. While there are other technologies to try to prevent a shipping container disaster, this was to be one of the most promising.

Such nuclear negligence takes other forms.

Back in 1998 and again in 2000, the United States and Russia agreed to open up a joint early warning center on formerly Soviet soil to detect and analyze missile launches in an effort to avoid accidental warfare. Delayed by 11 years, the center has still not opened.  However, since the agreement was made, nuclear brinksmanship has morphed into a state of complexity, and continues to do so. There are still old warheads for which there is no accounting, and more terrorist organizations and rouge governments seek nuclear capability.  The Times reported on November 14 that legal issues (like who is responsible for the construction of the center) have held up opening the facility.

Amazing. We are living in the time of North Korean nuclear weapons, Iranian development of nuclear technology and an unstable Pakistani warhead arsenal. Even Myanmar is suspected of wanting “the bomb.”  Al Qaeda seeks the bomb. It is ironic that Russians and Americans can cooperate with the complex International Space Station, but jointly we can’t open a building which might help prevent World War III.

The importance of such an early warning center is crystalized by recalling recent history. According to the International Relations Center in October, 2001, ”U.S. nuclear attack warning systems generated more than 1,150 serious false alarms between 1977 and 1984.” On January 25, 1995, the Russians thought an American missile was headed their way. In the minutes before a retaliation launch was being contemplated, the path of the missile was determined to be non-hostile. Even though told of the launch (designed to probe the Northern Lights), someone forgot to tell Russian rocket commanders. We came close…very close, to the end…because of nuclear negligence.

Yes. We are being too lax…too trusting that things will not go wrong.  What’s most troubling is the fact that both of these examples of malfeasance fit into the “completely avoidable” category. They are examples of  how accidents and incidents are allowed happen, and by then, of course, it is too late. We cannot rely on good luck to avoid nuclear devastation.  Quality control in our efforts to avoid nuclear winter needs to be job one.

The legal definition of  negligence is clear. It is ”the failure to use reasonable care.”  U.S. Courts explain ”Reasonable care is that degree of care which a reasonably careful person would use under like circumstances.  Negligence may consist either in doing something that a reasonably careful person would not do under like circumstances or in failing to do something that a reasonably careful person would do under like circumstances.” Applying these definitions, the helium-3 and early warning center examples shout NEGLIGENCE.

No reasonably careful individual would plan for and develop vital equipment to safeguard our ports that cannot ultimately be widely deployed because of a scarce ingredient. No reasonably prudent person would agree that early warning center is crucial and should be opened, and then just argue about legalities while our enemies seek access to technology, which if used or even threatened, make our other disputes trivial. We don’t just need one joint early warning center. The world could benefit several, jointly hosted by rivals.

Too many Americans think that since the fall of the Soviet Union in 1989, that we are safer, in terms of nuclear security, than during the days of the Cold War.  In fact, we are in a much more perilous situation thanks to the likes of proliferation profiteers and power hungry extremist regimes.

It is telling that the “Doomsday Clock” devised by the Board of Directors of the Bulletin of Atomic Scientists has been just 5 minutes from midnight since 2007, closer than it was during the cold war.  (In 1990 the clock was 10 minutes to midnight). We add to our peril and risk a closer proximity to the fateful midnight hour by the excercise of a culture of nuclear negligence in an era of enhanced risk. Since ICBM’s are no longer the only delivery vehicle, cooperation and planning cannot get caught up in details and tunnel vision.

We cannot afford to get sloppy when it comes to averting present-day nuclear threats, and yet, with the examples of helium-3 and the joint warning center, ”mistake prone“ is our reality.  To err is human, but to commit too much error in these hyper nuclear times may ultimately be inhumane. We must do better.

All countries are at risk with cargo container trucks. Above, China inspects a North Korean freight carrier.

One of the key postulates of Einstein’s theory of special relativity is that the speed of light in a vacuum is constant. This principle is called Lorentz invariance, and means that whatever the energy of the photons making up the ray of light, its speed is always the same – and it’s been on trial once again, courtesy of the Fermi Large Area Telescope (LAT) Collaboration.

Abdo et al. analysed the light coming from a distant and fleeting gamma ray burst to try and pick up any variation in the speed of its photons.

Gamma ray bursts (GRBs) are believed to be released during supernovae  and are the brightest events occurring in the universe – despite the fact that most of them are billions of light years away from Earth. The radiation emitted during a GRB is extremely intense, typically releasing as much energy in a few seconds as the Sun will release in its entire lifetime. They are good candidates for measuring a variation in light speed due to the cosmological distances the light has to travel to reach Earth – even tiny variations in photon speed are amplified enough to be revealed in the sharp features of the light curve emitted during the burst.

Researchers at the Fermi LAT Collaboration were alerted to the gamma ray burst they went on to investigate after it was picked up by both the Large Area Telescope and the Gamma-ray Burst Monitor . A photon, with an energy of 31GeV, emitted less than a second after the start of the burst was singled out  and used to find a limit for the variation of the speed of light.

In special relativity there is no length at which the Lorentz invariance should be broken. However, some theoretical physicists have other ideas. In order to formulate a “theory of everything”, they are  attempting to reconcile gravitational effects with quantum mechanics – creating quantum gravity. This implies that at the Planck scale (lengths of approximately 1.62 x 10^-33 cm) quantum mechanics should interact with gravity, influencing  the nature of space-time and so changing the speed of light.

In this study, Lorentz invariance was found to hold true down to 0.8 times the Planck length, providing a blow to quantum gravity but good news for Einstein – after over 100 years, his theory of special relativity still stands.

Reference: Nature doi:10.1038/nature08574

Image Credit: NASA/Swift/Mary Pat Hrybyk-Keith and John Jones

Gravedad cero. Imagina, como Newton, que la Tierra fuera hueca y te encontraras en su interior. Estarías flotando, completamente ingrávido, como los astronautas en el espacio, pero por una razón diferente. En el interior hueco de una distribución esférica de masa el campo gravitatorio es nulo. Newton lo demostró geométricamente como muestra este extracto de los Principia. Considera un punto P en el interior y dos conos con el mismo ángulo que atraviesan el cascarón. Como la ley de la gravead decae con la inversa de la distancia al cuadrado y la cantidad de masa en el cascarón contenida en cada cono depende de la distancia al cuadrado, la fuerza ejercida en P por ambos cascarones es idéntica pero de sentido opuesto. Sea cual sea P, la fuerza gravitatoria en P debida al cascarón es exactamente cero. Obviamente cualquier objeto exterior al cascarón que rompa la simetría esférica, como la Luna o el Sol en nuestro ejemplo, introducirá una fuerza gravitatoria muy débil pero matemáticamente no nula.

La demostración de Newton es geométrica e intuitiva. La clave es que la fuerza de la gravedad se proporcional al inverso del cuadrado de la distancia. La masa en el punto P puede ser cualquiera, siempre que sea puntual (su volumen es muy pequeño comparado con el de la esfera hueca). En los primeros cursos de física es habitual presentar una demostración más técnica de este teorema de Newton basada en el teorema de la divergencia de Gauss. Por ende, aplicable a la fuerza de Coulomb dentro de una distribución esférica de carga eléctrica.

En la teoría de la gravedad de Einstein, la relatividad general, el teorema de Newton o el teorema de Gauss también son aplicables aunque con una ligera salvedad. En el punto P la masa ha de ser nula, ya que por muy pequeña que sea deforma el espaciotiempo a su alrededor y la distribución esférica de masa deja de serlo, la simetría esférica se rompe (salvo que P se encuentre justo en el centro). Este resultado de la gravitación de Einstein se llama teorema de Birkhoff y es aplicable incluso al universo entero en su conjunto. Sus aplicaciones son múltiples. Por ejemplo, permite demostrar que la gravedad de la materia puede frenar la expansión del espaciotiempo debida a la Gran Explosión.

El teorema de Newton-Gauss-Birkhoff no se cumple en todas las variantes de la gravedad que han sido propuestas en las últimas décadas. Una de las más famosas es la teoría MOND, una modificación empírica de la gravedad newtoniana propuesta en origen para explicar la curvas de rotación de las galaxias sin necesidad de recurrir a la materia oscura. Para campos gravitatorios muy débiles, la teoría MOND corrige la ley inversa del cuadrado de Newton con un pequeño término de aceleración. La teoría MOND no cumple el teorema de Newton-Gauss-Birkhoff. Todo punto P dentro de una distribución esférica de masa hueca sufre una pequeñísima fuerza en dirección hacia el centro de la distribución de masas. La gravedad cero deja de serlo si la teoría MOND es correcta. Los interesados en los detalles matemáticos de la demostración pueden recurrir a Reijiro Matsuo, su PPT “Does Birkhoff’s law hold in MOND?,” 2008, o su artículo técnico De-Chang Dai, Reijiro Matsuo, Glenn Starkman, “Birkhoff’s theorem fails to save MOND from non-local physics,” ArXiv, 10 Nov 2008, last revised 16 Jun 2009.

Seguramente pensarás que los efectos del incumplimiento del teorema de Birkhoff por parte de la teoría MOND son despreciables a escala galáctica y a escalas mayores, pero no es así, como nos han contado recientemente Reijiro Matsuo, Glenn Starkman, “Screening and Antiscreening of the MOND field in Perturbed Spherical Systems,” ArXiv, 18 Nov 2009. Las dificultades de la teoría MOND a la hora de poder describir el comportamiento de los cúmulos de galaxias y de los supercúmulos de galaxias (donde se requiere la presencia de materia oscura) están relacionados con este problema técnico, como nos cuentan Pedro G. Ferreira, Glenn Starkmann, “Einstein’s Theory of Gravity and the Problem of Missing Mass,” ArXiv, 6 Nov 2009.

Resulta curioso que el problema de una nueva propuesta como teoría de la gravedad sea la Gravedad Cero.

Esta la contribución de la Mula Francis a “El Carnaval de la Física en Gravedad Cero. Hoy 30 de noviembre con motivo de la primera observación por parte de Galileo de un objeto celeste con su telescopio.” He de confesar que me enteré de esta iniciativa gracias a MiGUi, que a su vez se enteró en un tweet de Ciencia Kanija. Menéame y otros foros se han hecho eco de la misma. Enhorabuena, Carlo (Ferri) y Roi (Oliva).

Supposed that you’re having a amiable picnic on a hilltop with your fellow friends and family and gazing through the vast land of sceneries, you look up to the sky and you started to wonder why is it blue and not black? Well, the answer is simple, when we look towards the sun at sunset, we see red and orange colours because the blue light has been scattered out and away from the line of sight.

Image by GettyImages

To further our understanding of “The Sky”, we need to look into the past in the time of late 16th century where geniuses like Isaac Newton arose and shows us that white light doesn’t turns out to be white at all with a light prism but an array of colors of a rainbow which it had violet, indigo, blue, green, yellow, orange and red and those colors form a spectrum. The colours of light are distinguished by their different wavelengths. The visible part of the spectrum ranges from red light with a wavelength of about 720 nm, to violet with a wavelength of about 380 nm, with orange, yellow, green, blue and indigo between.  The three different types of colour receptors in the retina of the human eye respond most strongly to red, green and blue wavelengths, giving us our colour vision.

As you can observe the image above, you’ll notice that the visible light wavelength is between 400 nm and 700nm. De facto that the shorter the wavelength, the more blue you’ll see, why? Because it was caused by Rayleigh Scattering or electromagnetic radiation by particles much smaller than the wavelength of the light, which may be individual atoms or molecules. In other words, the light ray from the sun make contact with the molecules or any other microscopic debris in the atmosphere. In 1911, Einstein and his fellow colleague would put an end to this mystery of the molecules of oxygen and nitrogen in the air are sufficient to account for the scattering. They were even able to use the calculation as a further verification of Avogadro’s number when compared with observation.  The molecules are able to scatter light because the electromagnetic field of the light waves induces electric dipole moments in the molecules.

That was the title of a ground-breaking article published in 1935 in the Physical Review by Einstein, Podolsky andRosen (EPR). In this article they brought to the attention of physicists the strange correlations predicted by quantum mechanics for observations involving what are now called entangled systems. They used those predictions to argue that quantum mechanics, which had already been very successful in explaining many phenomena at the atomic level, gives an incomplete description of reality.

I’ve been asked a few times to write a blog entry about EPR to the layman reader, and so here it is. The details may take some attention to follow, but it is a nice story, which culminates with what has been called “the most profound discovery of Science” [H. Stapp]. Of Science, not just Physics. And he didn’t specify just the 20th century. So bear with me.

Before the EPR paper, Bohr, Heinsenberg and others had already set up the standard interpretation of the then-young quantum theory; the development of the basic postulates was completed around 1927, after a couple of decades of work by those physicists and others such as Schrödinger, Planck and Einstein himself. This interpretation, commonly referred to as the “Copenhagen interpretation”—in reference to the city where Bohr’s institute was located—painted a very unsettling picture of reality for the physical intuition of Einstein and his co-authors.

In the picture of Bohr and Heinsenberg, quantum systems cannot be said to have physical properties independently of a process of measurement that can determine them empirically. Since there are multiple ways in which one can observe a quantum system, and since some of those are incompatible observations (for example, one can measure the position or the momentum of a particle, but not both at the same time, with arbitrary accuracy), then it follows that not all physical properties can be said to have simultaneous existence, in the Copenhagen view.

[The term "physical properties" has in fact fallen in disuse when talking about quantum mechanics, being replaced by the less metaphysically committed observables; similarly, the term object has been replaced by system.]

According to the Copenhagen interpretation, if one decides to measure the position of a system, then “position” will have an empirical meaning, and it will be meaningless to ask what the “momentum” of the particle would have been if it had been measured instead. This was reflected mathematically by Heinsenberg’s Uncertainty Principle, which states that one cannot reproducibly measure incompatible observables of a physical system with arbitrary precision.

Not being able to determine something with arbitrary precision does not necessarily imply that it doesn’t exist, of course. Einstein, Podolsky and Rosen noticed that the correlations that quantum mechanics predicted between what was later termed (by Schrödinger) entangled systems could be used to challenge the Copenhagen interpretation. With an entangled pair of particles, sent to two distant observers—usually called Alice and Bob these days—it would be possible for one observer (Alice, say) to determine with arbitrary precision either of two incompatible properties such as the position or the momentum of Bob’s system, at a distance, without touching Bob’s system or allowing time for any communication to occur (with a signal not exceeding the speed of light) between the two sub-systems.

It would be absurd, in the light of Einstein’s theory of relativity, which postulated a limit to the velocities of physical systems—the speed of light—to imagine that any kind of instantaneous “action at a distance” could connect the two subsystems, and EPR concluded that because Alice could determine either of them at a distance at her will, the properties associated with both position and momentum must have existed before they were measured.

Although it challenged the orthodoxy, this was nothing more than a careful defence of the common sense idea behind most of modern science, that correlations can always be explained by a sequence of local events. If there is an outburst of a disease at around the same time in different locations, say, one would look for a common cause for that coincidence—presumably some previous interaction between the patients allowed the transmission of a pathogen; they must have either come in close contact or some microorganism must have been transmitted through the air between the two patients. All that EPR were defending was that there must be unknown “microorganisms” (later termed in that context “hidden variables”) responsible for generating the correlations.

For some strange reason, perhaps because of the eloquence of Bohr’s metaphysical positions, or perhaps because it was more practically useful to think of the theory in Bohr’s way, EPR’s view was largely ignored for at least three decades. This was aided by some mistaken “no-go” theorems, such as that due to Von Neumann, which (erroneously, it was much later realised) purported to show that no theory of hidden variables could reproduce the quantum mechanical predictions.

The first to show (indirectly) the error in Von Neumann’s “theorem” was Bohm, who in 1952 developed precisely what Von Neumann claimed to have demonstrated to be impossible: a hidden-variable theory of quantum phenomena which agreed with all empirical predictions of the “bare theory” formulated in the Copenhagen fashion. It was however, an explicitly nonlocal theory. Particles had definite positions at all times, but they could affect each other instantaneously, at a distance, in precisely the way that EPR rejected out of hand as absurd. Later, in 1964, Bell showed, after pointing out the error in Von Neumann’s alleged proof, that nonlocality was indeed not an accident of Bohm’s formulation, but a necessary feature of any theory which attempts to explain quantum phenomena (and ultimately, the world) in terms of underlying physical properties existing independently of the processes that reveal them.

Bell showed—through what is now called Bell’s theorem—was that the correlations between entangled quantum systems were much stronger than EPR realised. The correlations considered by EPR were no more mysterious than the correlations between the socks of one physicist called Bertlmann, as humourously illustrated by Bell himself:

…The philosopher in the street, who has not suffered a course in quantum mechanics, is quite unimpressed by Einstein–Podolsky–Rosen correlations. He can point to many examples of similar correlations in everyday life. The case of Bertlmann’s socks is often cited. Dr. Bertlmann likes to wear two socks of different colours. Which colour he will have on a given foot on a given day is quite unpredictable. But when you see that the first sock is pink you can be already sure that the second sock will not be pink. Observation of the first, and experience of Bertlmann, gives immediate information about the second. There is no accounting for tastes, but apart from that there is no mystery here. And is not the EPR business just the same?…

[J. S. Bell, in “Bertlmann’s socks and the nature of reality”,
Speakable and Unspeakable in Quantum Mechanics,
Cambridge University Press]

The EPR business, Bell showed, was not the same. Bell was able to show that the correlations between the multiple incompatible observations which are available to be performed by Alice and Bob cannot be given any local explanation whatsoever, even if you allow the most general imaginable model (called a Local Hidden Variable (LHV) model) by which the outcomes of those observations could be correlated. With the type of state EPR were considering, the correlations between the same measurements (position at Alice/position at Bob, momentum at Alice/momentum at Bob) was amenable to a LHV explanation, as pointed by EPR; but when some other equally possible observations are considered, a LHV model is no longer possible. This would be demonstrated by the violation, by a carefully set-up experiment, of what are now called Bell inequalities—mathematical inequalities that follow logically from the assumption of a LHV model.

Up to some open technical problems (due to logical loopholes exploiting experimental imperfections) those correlations have been observed, and Bell inequalities violated, in multiple labs around the world, since the work of Aspect and other in the 1980’s. There really are correlations in the world that cannot be given any possible local explanation. In this (negative) sense, the world really is nonlocal, independently of whether or not hidden variables exist underlying quantum phenomena.

[People often confuse the commonly used term "local realism" to be a conjunction of two independent terms --- "locality" and "realism" --- and choose to maintain "locality", thus claiming that Bell's theorem suggests the failure of "realism". It is not always clear what is meant by "realism" in these contexts, and it is my considered opinion that locality (or more precisely, what Bell termed "local causality") is proven to be false by Bell's theorem. Which is a distinct assertion from saying that something like the "active" nonlocality of Bohmian mechanics is true. The failure of local causality is merely the assertion that a local description of the phenomena is impossible. Even if there are no hidden variables, at the very least one must treat the entangled system as one indivisible system, not composed of separable parts amenable to independent (but correlated) descriptions.]

Which takes us back to the original question: “Can quantum mechanical description of physical reality be considered complete?” The answer is still debatable, if what the question is asking is whether or not hidden variables underlying quantum phenomena really exist. But in search of an answer, EPR, Bohm and Bell have unearthed the astounding fact that our classically intuitive descriptions of a reality in which things exist independently of each other, interacting only locally to create the multiplicity of phenomena we experience, is demonstrably untenable. Anybody with a scientifically or philosophically inclined mind who is not bothered by this discovery—as pointed out by an anonymous Princeton physicist to the physicist David Mermin—”must have rocks in [their] head”.

Yet another interview with Richard Dawkins on the sesquicentennial of the publication of On the Origin of Species. In the following he addresses the evolutionary future of humanity (to the extent that he can), the idea of thought and reason, what there was before the big bang (evolution vs. cosmology; addressing the fallacy between the two), Ray Comfort, and evolutionary proof for the dis-existence of a God.

My favorite quote:

Daniel Dennett, the American philosopher, described it as the best idea any one ever had. It’s such a powerful idea, it’s an extremely simple idea, but the amount that it explains is simply colossal, it explains the whole of life, the diversity of life, the beauty of life, and above all the illusion of design. Living things look as though they have been designed at a fantastically complicated level, what, and before Darwin came along everybody thought that they were designed. What Darwin showed was that you can get the illusion of design, with virtually nothing, I mean with a very, very simple idea using the ordinary, benign laws of physics.

Beautify put.

And, of course, the blatant dismissal of Ray Comfort:

There is no refutation of Darwinian evolution in existence. If a refutation ever were to come about, it would come from a scientist, and not an idiot.

Evidence!

From YouTube:

November 24, 2009 on CNN

Speaking to CNN on the 150th anniversary of the publication of Darwin’s seminal work “On the Origin of Species,” Dawkins said the evidence to support the theory that life on earth came about through natural selection, and not design by God, was “now massively buttressed by molecular evidence.”

And referring to U.S.-based evangelist Ray Comfort, who argues that the universe and life is the result of an intelligent creator, Dawkins said: “There is no refutation of Darwinian evolution in existence. If a refutation ever were to come about, it would come from a scientist, and not an idiot.

Hoy, 26 de noviembre, el profesor Gregorio Millán Barbany cumpliría 90 años de edad. Falleció hace un lustro uno de las personalidades que más contribuyó, por sus cualidades polifacéticas, al desarrollo científico y tecnológico español. Gregorio Millán inició su actividad investigadora en combustión (aerotermoquímica) gracias a su colaboración con Theodore von Kármán, padre de las ciencias aeronáuticas americanas y creador del Jet Propulsión Laboratory (JPL) del Caltech (Instituto Tecnológico de California), creando el Grupo de Combustión del INTA (Instituto Nacional de Técnica Aeronáutica). Gregorio Millán mostró con su ejemplo cómo se podía contribuir desde España al desarrollo de las ciencias aeroespaciales y facilitó el acceso a los foros internacionales y a la investigación en temas de gran importancia práctica a muchos ingenieros jóvenes españoles, entre ellos, a Amable Liñán, autor de su obituario en El País.

La figura de Theodore von Kármán, “el hombre capaz de entrar el último en una puerta giratoria y salir el primero,” es fundamental para el desarrollo científico y tecnológico español durante la segunda mitad del s. XX. Fue invitado por el profesor Esteban Terradas, director del INTA, en el verano de 1947, durante una breve visita de pocas horas a España, a impartir un ciclo de cuatro conferencias en otoño de 1948. Desde entonces el INTA y von Kármán iniciaron una relación de “amor” que permitió que muchos ingenieros aeronáuticos españoles se especializaran en prestigiosos centros de investigación de los Estados Unidos, como el CalTech, permitiendo la incorporación del INTA a la corriente aeronáutica mundial, incluyendo la celebración de dos importantes congresos científicos en España en 1955 y 1958. La financiación del grupo de investigación en combustión (aerotermoquímica) del INTA, a cargo del profesor Gregorio Millán (breve biografía), corrió en gran parte a cargo de la Oficina de Investigación Científica de las Fuerzas Aéreas de los Estados Unidos. Más detalles en Gregorio Millán, “Von Kármán y la investigación aeronáutica española,” y en los Paneles de Ingeniería Aeronáutica y Astronáutica. Los interesados en la historia del INTA pueden recurrir a Gregorio Millán, “Los orígenes del INTA.”

El Grupo de Combustión dirigido por Gregoria Millán ha dado lugar a figuras en este campo tan relevantes como Amable Liñán Martínez, autoridad mundial en el campo donde las haya. Becario de dicho grupo en 1958, Ingenierio Aeronáutico en 1960 por la Universidad Politécnica de Madrid, Aeronautical Engineer en 1963 por el CalTech, doctor en 1966, y catedrático de Mecánica de Fluidos desde 1965. Otras figuras en los Paneles de Combustión. La presentación del profesor Francisco Payri de la Univ. Politécnica de Valencia para la concesión de un Doctorado Honoris Causa a Liñán por dicha universidad, así como su discurso merecen una lectura. Amable parte de Prandtl (1904), von Kármán (1914), Millikan (1928), pasa por su padre científico Gregorio Millán (1948) y acaba glosando al espectacular Airbus A380.

Sirva esta entrada como homenaje de un servidor al padre de la aerotermoquímica (junto a von Kármán, por cierto, uno de los padres de la Matemática Aplicada en los EEUU).

Now there’s an interesting take on the whole time-space conundrum. If you attach different states to the concept of time (think of the varying states of water depending on energy input: solid/ liquid/vapor) Petr Hořava, a physicist at the University of California, Berkeley figures you can clean up some of the messy, intractable problems physics has been having since Einstein decided to marry space and time together.

This article from Scientific American discusses the implications

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The Condensed Matter Physics program supports experimental, as well as combined experiment and theory projects investigating the fundamental physics behind phenomena exhibited by condensed matter systems. Representative research areas in such systems include: 1) phenomena at the nano- to macro-scale including: transport, magnetic, and optical phenomena; classical and quantum phase transitions; localization; electronic, magnetic, and lattice structure or excitations; superconductivity; and nonlinear dynamics. 2) low-temperature physics: quantum fluids and solids; 1D & 2D electron systems. 3) soft condensed matter: partially ordered fluids, granular and colloid physics, and 4) understanding the fundamental physics of new states of matter as well as the physical behavior of condensed matter under extreme conditions e.g., low temperatures, high pressures, and high magnetic fields. Questions of current interest that span these research areas are: How and why do complex macroscopic phenomena emerge from simple interacting microscopic constituents? What new physics occurs far from equilibrium and why? What is the physics behind the behavior of matter confined to the nanoscale in one or more dimensions? What is the physics of spin systems and quantum states of matter that could lead to their coherent manipulation and control?

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Description:
This program supports theoretical and computational materials research and education in the topical areas represented in DMR programs, including condensed matter physics, polymers, solid-state and materials chemistry, metals and nanostructures, electronic and photonic materials, ceramics, and biomaterials. The program supports fundamental research that advances conceptual, analytical, and computational techniques for materials research. A broad spectrum of research is supported using electronic structure methods, many-body theory, statistical mechanics, and Monte Carlo and molecular dynamics simulations, along with other techniques, many involving advanced scientific computing. Emphasis is on approaches that begin at the smallest appropriate length scale, such as electronic, atomic, molecular, nano-, micro-, and mesoscale, required to yield fundamental insight into material properties, processes, and behavior and to reveal new materials phenomena. Areas of recent interest include, but are not limited to: strongly correlated electron systems; low-dimensional systems; nonequilibrium phenomena, including pattern formation, microstructural evolution, and fracture; high-temperature superconductivity; nanostructured materials and mesoscale phenomena; quantum coherence and its control; and soft condensed matter, including systems of biological interest.

For two hours I struggling with the physics test. When I finally was finished it felt pretty good. I actually think I might pass it!

Ugh, now I have to wait for the results. I don’t know how long eather. I want to know as soon as possible! Hate waiting

Well nature is at it again.  Goldbogen and friends recently published an article on whale feeding that really captures the importance of scaling in biology, or more accurately zoology.  This blog post on fin whale feeding mechanics seems to me to be a fresh and physical approach to an interesting question.  Lunge feeding whales need to be big to pull in a lot of water and hence food.  But the bigger the whale the more food it needs to pull in.

You can see where this is going.  Nature has obviously settled on a finite size for the whale species.  This begs the questions, does the current whale size represent the most efficient configuration given the food density the whale normally experiences (not really straightforward given the difference in scaling laws based on size according to Goldbogen et al)?  If yes, can the whale’s size be controlled by controlling the food density?  If not, why is the whale and inefficient size to begin with?  Given current over fishing problems and our continued assault on marine life in general, I think a shrinking food density will begin to take a toll on these whales soon.  So that experiment may just perform itself.

This is one of the most beautiful, amazing projects I’ve seen in a long, long time, and the man who is making these is a genius. If you haven’t already seen this go watch all of them now!!!!  These videos and mp3s have gotten me through a tough couple of weeks.  Donate!

http://symphonyofscience.com/

Here are my two favorites:

NO PLANE flew into Building 7 at the World Trade Centre. But seven hours after the Twin Towers collapsed in flames on September 11, 2001, this third skyscraper fell too.

Like its larger neighbours, it fell rapidly, vertically, almost symmetrically, like an implosion. It took 5.4 seconds for its 47 storeys to complete their fiery descent.

Building 7 has preoccupied conspiracy theorists ever since. Many believe it was brought down by controlled explosions. And if it was, so were the Twin Towers. And if they’re willing to believe that, it is not such a big leap to conclude that the whole atrocity was a US Government plot. They have not been silenced by an official report that concludes their theories are bunkum. It didn’t help that it was released almost seven years later, in August last year.

The National Institute of Standards and Technology spent three years investigating Building 7. It names fire as the culprit. Fire – fuelled by office furnishings, aided and abetted by the thermal expansion of structural elements.

“Heating of floor beams and girders caused a critical support column to fail, initiating a fire-induced progressive collapse that brought the building down,” said the lead investigator, Shyam Sunder. The conclusion that this was an ”extraordinary event” – the world’s first known total collapse of a tower caused by fire – only emboldened the doubters.

Explosives? The institute concludes that the smallest blast capable of crippling the third tower’s critical column would have produced a “sound level of 130 to 140 decibels at a distance of half a mile”. No witness reported it.

The 9/11 Truth Movement points to the discovery of thermite, a potential explosive. The institute replies that the same metal compounds would have been present in the construction.

The institute’s finding is less sensational, but perhaps more alarming for people who frequent towers. Debris from the collapse of the first tower ignited fires on at least 10 floors of Building 7. These uncontrolled fires caused thermal expansion of steel beams on lower floors, damaging floor framing on multiple floors.

”Eventually, a girder on floor 13 lost its connection to a critical interior column that provided support for the long floor spans … Floor 13 [collapsed], beginning a cascade of floor failures …”

The really scary part? This happened at hundreds of degrees below what had been anticipated in fire-resistance ratings. The institute recommended urgent evaluation of towers, improved thermal insulation and resistance for building materials, and structural systems to prevent ”pan-caking” or progressive collapse.

- smh

Splitting Time from Space—New Quantum Theory Topples Einstein’s Spacetime: Scientific American

Hořava’s theory has been generating excitement since he proposed it in January, and physicists met to discuss it at a meeting in November at the Perimeter Institute for Theoretical Physics in Waterloo, Ontario. In particular, physicists have been checking if the model correctly describes the universe we see today. General relativity scored a knockout blow when Einstein predicted the motion of Mercury with greater accuracy than Newton’s theory of gravity could.

Can Hořřava gravity claim the same success? The first tentative answers coming in say “yes.” Francisco Lobo, now at the University of Lisbon, and his colleagues have found a good match with the movement of planets.

Others have made even bolder claims for Hořava gravity, especially when it comes to explaining cosmic conundrums such as the singularity of the big bang, where the laws of physics break down. If Hořava gravity is true, argues cosmologist Robert Brandenberger of McGill University in a paper published in the August Physical Review D, then the universe didn’t bang—it bounced. “A universe filled with matter will contract down to a small—but finite—size and then bounce out again, giving us the expanding cosmos we see today,” he says. Brandenberger’s calculations show that ripples produced by the bounce match those already detected by satellites measuring the cosmic microwave background, and he is now looking for signatures that could distinguish the bounce from the big bang scenario.

Hořava gravity may also create the “illusion of dark matter,” says cosmologist Shinji Mukohyama of Tokyo University. In the September Physical Review D, he explains that in certain circumstances Hořava’s graviton fluctuates as it interacts with normal matter, making gravity pull a bit more strongly than expected in general relativity. The effect could make galaxies appear to contain more matter than can be seen. If that’s not enough, cosmologist Mu-In Park of Chonbuk National University in South Korea believes that Hořava gravity may also be behind the accelerated expansion of the universe, currently attributed to a mysterious dark energy. One of the leading explanations for its origin is that empty space contains some intrinsic energy that pushes the universe outward. This intrinsic energy cannot be accounted for by general relativity but pops naturally out of the equations of Hořava gravity, according to Park.

Instead of visiting today’s Physics lecture, I went to ALDI. (Which is a supermarket.) While waiting in the queue, I had the opportunity to watch two cashiers practicing.

As most supermarkets ALDI provides triangular bars to be used as stop signs at the checkout’s conveyor belt. (Almost like “Toblerone” except you can’t eat ‘em.) This bars are supported at a runner parallel to the conveyor. The problem is that people always take them from the back end of the runner while the cashier puts them on at the opposite end. If there are only a few bars left, the cashier might wish to push them back in order to make things easier for his customers. It was quite exciting for me to watch two ways of doing this.

Cashier A knocked his bar firmly against the ones already lying at the runner. The bars are made from aluminum sheets. Neglecting the (rather thin) terminal plastic capes, they show almost ideal elastic behavior. Hence the bar hitting the first obstacle of equal mass preforms a complete transfer of its momentum. (As illustrated in this animation.) This is repeated with every bar. In the end only one (namely the last) bar is pushed to the end of the conveyor while all others stay in place.

Next time he knocked the bar harder — making things even worse. Now the last bar collided with the stopper at the end of the runner, was reflected and the reaction occurred a second time the other way round, leading to an unchanged arrangement of bars except he got back the one he just propelled forward.

Cashier B, however, was more concerned about the physics behind his working place. He took the bar and accelerated the other bars gently by pushing it against them while still holding it in his hand. When he could no longer stretch his arm, he let the bar go and was satisfied by the intended movement of all the bars to the runner’s end.

So you see, it’s quite crucial to pay attention to your physics lectures. What was the first sentence again?

Wikipedia has another nice illustration of this phenomena:

568.  theoretical physicsspeaks on theoretical physics; (Nov. 18, 2009)

569.  I am mostly the other I; (Nov. 19, 2009)

570.  Einstein speaks on General Relativity; (Nov. 20, 2009)

571.  Einstein speaks of his mind processes on the origin of General Relativity; (Nov. 21, 2009)

572.  Everyone has his rhetoric style; (Nov. 22, 2009)

Today, I found myself in an internet debate over the topic of Religion. A certain blogger who shall remain anonymous has made it their duty to call out religion and any beliefs that one may have as ‘weak’ and an excuse for the ‘misguided actions’ they apparently have ‘no control over’ (because we’re all morally weak, right?). They explained that religion is like a ’safety net’ in which those who believe ‘find comfort in’ when they fall victim to peer pressure.

I’d like to say this right now – and I don’t want to sound like a freaky religious person nor do I want to force my beliefs upon anyone – you have just as much proof that God does not exist as I have proof that he does exist. This universal debate has been ongoing for centuries and I fear it will go on for many more. As much as I’d like for the world to be a simple and peaceful place, it never will be while debates like this still exist.

[Science vs God]

Anyone who raises a point on one side can always be rebutted by another point on the opposing side. Scientists have spent lifetimes trying to find breakthroughs and explanations for why things are the way they are. There would be no need for these findings if everyone believed that it was created by someone greater than we are – someone above all of humanity – someone like God. Unfortunately, there will always be people who do not believe – the ’seeing is believing’ people. To such a point; one could argue that the earth is evidence, the sun, the air we breathe, humans, animals, nature…which is what I believe. But to those who don’t it won’t do anything but spark up the debate all over again.

Likewise, man has studied the bible through and through trying to match up the pieces of info and history of our universe. Christianity is preached all over the world – in most countries – and it has the biggest population of followers. Clearly, it is most logical explanation for why things are the way they are, and most people can see that. Though, again, to the non-believers, it’s all a myth; so really there’s no way of convincing them nor is there a ‘logical argument’, they would say.

While I have read the various theories of evolution and of the big bang, and the scientific evidence that supports it; I still can’t believe that life can be controlled/occur as a result of two random atoms colliding. Something as perfect, complex and intricate as the human body surely could not have been created by accident; by anything other than someone like God. How about babies? How do they survive in the womb? How are they automatically born with the reflex action of suckling when stroked on the cheek? How can something as simple as the anatomy of spider create such versatile and complicated webs?

Lol; I’m preaching aren’t I? I don’t mean to. But anyways, back to my point. The earth we live on is but a tiny spec of dust in a vast universe which stretches out further than any horizons and expands across any of our imaginations. You cannot begin to comprehend how large it or what else exists out there. It really is amazing. I can’t seem to believe that this is all a result of an accident though – that once upon a time there was nothing, and now there is a whole galaxy and solar system.

To the non-believers who base their opinions upon real, hard evidence in front of them – the ones who let science take over their life – I would just like to say this: have. some. respect. We may not all be smart geeks like you, we may not understand the laws of physics, or the basics of chemistry and biology – but that is no reason to undermine our beliefs and faith. I am sick to death of people shunning the bible as a mythological fairytale that was created by middle-aged men with no lives; and religion as the ‘weak’ alternative to living life.

Putting your faith into something/someone greater than who we are is not at all weak. I do not believe in God because I am scared of being eternally damned or suffering during my second life. I am not forced to believe in God by my parents, nor to attend Church on Sunday mornings. This my choice.

Religion is choice. You can’t say you’re a Christian just because you’ve been to Church every Sunday of your life since the day you born and then go out and do everything the bible tells you not to do. Sure, you may have gone to Church your whole life, but by not following God’s law, you are making a choice – to not be a good follower/faithful.

I’m not saying that doing what you want and not following the bible is weak, either. Like I said, it’s a choice. I choose to follow God’s law and put my faith in Him – and because of that I feel strength, not weakness. Just like people choose not to follow Him because they don’t believe there is enough evidence. I do no fear of being eternally damned if I sin once because I know that God will forgive me if I am truly sorry. Likewise, I don’t say I’m a believer purely because I don’t want to be eternally damned – I’m a believer because I have gone to Church practically every Sunday of my life and I have listened. I read the bible and I see the evidence in my life. Believing in God does not make me fearful; but rather strong and proud. I know that wherever I go and whatever I do, I will always be safe because God will always be right by my side.

So, to conclude – this really was in retaliation to the blog I read earlier today and also an opportunity for me to vent my anger and feelings. To the non-believers – I have respect for what you believe, please have some respect for what I believe. To those who may wonder – why do good people suffer? Why is there so much evil in the world? Well I’ll tell you; these are God’s trials – tests, if you will, to measure your faithfulness and loyalty to God. Without bad, there’d be no good to separate it from. Without suffering, there would be no compassion or forgiveness.

Arguing about whether God exists or not/any religion for that matter – is always going to be a moot debate. No one will ever win. Stop doing it. Respect each other.

That’s all I have to say for now.

-Ania

[edit]

P.S I realise that in my last post I mentioned my love for the show ‘The Big Bang Theory’. Granted, my love stems only from the fact that it is an extremely hilarious show – I am not a psycho, hypocritical religious person.

By Columnist Harry Trunckles

The other day, I was talking to my wife Anna about that no good asshole she left me for and she said “He’s light years beyond you Harry, don’t even compare yourself to him!”

I just slapped her face right there. First of all, anyone who thinks that light years are a unit of measurement for how poor of a husband I am clearly doesn’t understand the basics of physics. Light years describe how time is relative to light. This is similar to using “dog years” to describe your beloved pet’s rapid decrepidation. And a light year is roughly the length of time it takes for the universe to begin and then end. Kind of a useless measurement for us humans in my opinion.

Particle Physicists (More like particle suckacists! Zing!) have debated about the nature of light for the last few years. Is it a particle or is it a wave? Since this question isn’t being hotly debated by wave physicists, I am going to assume that the particle physicists are a bunch of biased bastards. There has actually been a number of rigorous studies done to determine this. Some indicated it was a wave. Some indicated it was a particle. The lazy conclusion they came to was that light was both a particle AND a wave. Ok, before you call them all idiots for arriving at such a counterintuitive notion, let me tell you about how they found this out. You’ll laugh even harder.

Anyway, let me go into the detail of this horrible Freudian-projected nightmare. The scientist would tell you that if you have a photon entering two slits, then it could theoretically interfere with itself if you do not observe it. If you do observe it, then the photon will not interfere with itself. This is all just some bullshit fantasy that if your wife doesn’t observe you having sex with two other women, it’s okay, since there’s some kind of penile (represented by photons) interference. Jeez scientists, grow up!

Its so patently obvious that this is the Freudian expression of the scientist’s desire for an adulterous threesome. One in which his penis interferes with itself. Guess what science guys, I tried that excuse, but my wife still won’t return my calls. Kind of punches a hole in your logic, don’t you think?

Back in the day, scientists wanted to know if there was this luminiferous ether that light travelled through. They never found the luminiferous ether! No shit, you particle dumbassicists! Didn’t you read Genesis chapter 1? God spoke and He bespoke light. Clearly light is supernatural in origin. You dipshiticists. However, to be fair, science was right about there needing to be a medium for light to travel through. You see, sound can’t travel in a vacuum. And since light is composed of God Voice Particles (GVP), any over-arching theory of cosmology has to include something like deity air (not some stupid ether!) for the sound particles to travel through.

My colleagues, occasionally secular godless science can be right. One thing physicists got right was when they said that at the speed of light (you know, 9,999 miles per hour), time does not pass, so light experiences no aging just like God. So clearly light could have only originated from God. My goodness, what do these jerks at MIT do all day not to realize that ageless particles prove their own origin – their own origin being that of God!

Speaking of time coming to a stop, there’s this stupid theory called Relativation Theory (you’d think it would be about relatives or something) that says that time slows down as you approach the speed of light. Let me tell you, I tried driving really fast in my car, and not only did time not slow down, but it actually seemed to pass faster as it didn’t take as long to get to my work. I was 20 minutes early! Wow, who came up with such a terrible theory?

Another claim by physicists is that light can’t escape a black hole. How absurd! Being the natural skeptic that I am, I went into my backyard where there are plenty of holes. I tossed a mirror down one and shone my flashlight into the hole. The beam of photons bounced right back out. Maybe the scientist that came up with this theory fell down a crevasse as a kid or was just really scared of the dark. Seems like astronomy might be a bad field to work in for you guys.

Light is actually not as complex as people think it is. The mainstream opinion is that humans only percieve a limited spectrum of light known as the “visible” and that there is also “Infrared”, “Ultraviolet,” “Radio,” “X-Rays,” and a bunch of other satanic beams of light rays. The truth is that scientists saw their funding drying up after they discovered Red through Purple and went ahead and made up some new kinds of light.

Let me conclude on this note. A particle physicist once asked me if a cat in some box was dead or alive due to some quantum mechanical mumbo jumbo aptly named Schumaker’s Cat. What a stupid question. I kill my neighbor’s cats routinely by boxing them up and tossing them into a river. So I’m fairly certain that most of the time when a cat is in a box, it is dead. Especially after I run it over with my Ford truck! In the interest of testing this ridiculous claim, I took the litter of kittens my neighbor was trying to find a home for and put them all in a box. Well, big disappointment. They took a whole day and a half to die, and no matter how many times I observed them they never came back to life.

Do you really want to believe a bunch of eggheads who are afraid of the dark, like to cheat on their wives, think cats can come back to life literally, and ask you stupid riddles about dead cats?