Hoy martes 19 a las 19:00 horas, hora española de Madrid, en el CERN de Ginebra se emitirá en directo la conferencia “The Science Behind Angels and Demons: No Laughing Antimatter,” en la que intervendrán físicos de gran renombre como Rolf-Dieter Heuer, Leon Lederman y Boris Kayser. Discutirán la verdadera ciencia detrás de la película, la ciencia del CERN, el LHC, la antimateria y la física de partículas en general.

Una oportunidad única que no debes desaprovechar. DIRECCIÓN WEB.

Isaac Newton’s theory of gravitation, a milestone of physics theory and science overall for centuries, is increasingly undergoing heretical attacks. Two new studies, by the physicists Pavel Kroupa and Manuel Metz from the University of Bonn in collaboration with Gerhard Hensler and Christian Theis from the Institute of Astronomy of the University of Vienna together with Helmut Jerjen from the Australian National University, Canberra, show results about so-called “satellite galaxies” at the periphery of the Milky Way which could rock the theoretical foundations of standard physics theory.

As modern cosmologists rely more and more on the ominous “dark matter” to explain otherwise inexplicable observations, much effort has gone into the detection of this mysterious substance in the last two decades. Yet, “no direct proof could be found that it actually exists”, Gerhard Hensler explains. Even if it does exist, dark matter would be unable to reconcile all the current discrepancies between actual measurements and predictions based on theoretical models. Their only problem is that they conflict with Newton’s theory of gravitation.

In these two new studies, scientists have examined the so-called “satellite galaxies”, a term used for dwarf galaxy companions of the Milky Way, some of which contain only a few thousand stars. Best cosmological models describe they exist presumably in hundreds around most of the major galaxies. Up to now, however, only 30 such satellites have been observed around the Milky Way, a discrepancy in numbers which is commonly attributed to the fact that the light emitted from the majority of satellite galaxies is so faint they remain invisible.

A detailed study of these stellar agglomerates has revealed some astonishing phenomena: “First of all”, Kroupa explains, “there is something unusual about their distribution. Satellites should be uniformly arranged around their mother galaxy, but this is not what we found”.

Physicists do believe this phenomenon can only be explained if the satellites originated a long time ago through collisions between younger galaxies. Or one must assume that some basic fundamental principles of physics theory have hitherto been incorrectly understood. “The only solution would be to reject Newton’s classical theory of gravitation”, says Pavel Kroupa. “We probably live in a non-Newton universe. If this is true, then our observations could be explained without dark matter”. Such approaches are finding support amongst other research teams in Europe, too.

It would not be the first time that Newton’s theory of gravitation had to be modified over the past hundred years. This became necessary in three special cases: when high velocities are involved (through the Special Theory of Relativity), in the proximity of large masses (through the theory of General Relativity), and on sub-atomic scales (through quantum mechanics).

Famous astrophysicist Bob Sanders from the University of Groningen declares: “The authors of this paper make a strong argument. Their result is entirely consistent with the expectations of modified Newtonian dynamics (MOND), but completely opposite to the predictions of the dark matter hypothesis. Rarely is an observational test so definite.”

This problem of the origin and nature of satellite galaxies and their implications for fundmental physics theory will be discussed by experts at a one-week long international conference to be held end of May in the physics theory Centre of Bad Honnef near Bonn. Moreover, Gerhard Hensler who studies with his research group at the University of Vienna in a FWF-funded project the evolution of satellite galaxies by means of computer simulations must extend the parameter space of models according to these observational facts.

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I am always fascinated in the way that physics theory shows how the world functions in various paradoxes. With string theories rounding up the fluctuation in the motion of particles in the universe and the theory of relativity shedding a new dimension on the wrinkle in time, I believe that science gradually moves up to another vicious cycle recurring what have been missed out by former minds and developing a more definite explanation of the universe. Physical science is always an interesting subject as it scopes everything within the reach of our knowledge. Yet what really impresses me is what I came across about Newton’s discussion on human affair and how it functions along with universal laws. It is true that human emotion is very puzzling that it constantly escapes human knowledge, but with regards to how someone behaves in time, it could easily be predicted as easy as an apple is expected to fall  to the ground. Negative is usually followed by positive or the other way around. When you are crying right now, you will eventually laugh in the coming days; when you are alone, you will definitely find company. Why? In life we are following a path and whether we try to diverge from it, universal laws will always keep us back to the track… just like what Newton said, that for every action there is an equal but opposite reaction.

So why despair when you know you will be happy?

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P.S. In every law there is an exemption and this young lady is one. Mikaela Irene Fudolig started to be very brilliant and will always be brilliant all throughout. I wonder if studying physics theory makes us trancend its laws. Correct me if I’m wrong.

What the hell is it about Einstein’s theories of relativity?  For some reason, physics theory cranks seem to have a fetish for trying to undo or modify relativity in an effort to push their own “theories” of physics theory.  In the process, these folks often display a glaring lack of understanding of the very physics theory they are proposing to overthrow, and sometimes they even venture into the realm of conspiracy mongering. I like to refer to this particular species of woo as the “Einstein cranks.”

In particular, I have had an interesting series of discussions recently with one such physics theory crank on the JREF Forum. Allow me to illustrate some examples of how various physics theory woo-meisters often get physics theory dead wrong and display logical fallacies of all stripes when making their arguments.

Read the rest of this entry »

It turns out those jammy little double-walled coffee cups I bought work well for keeping coffee warm; however I am unwilling to subject them to the compressive stress necessary to cycle my Aeropress.  I have a number of inexpensive porcelain mugs which are both known to me to be strong enough, and pointedly expendable.

In spite of that, I took the opportunity this morning afternoon to experiment with the amount of force I used.  It turns out that a very light push – i.e. with the fingers of one hand – will complete a press cycle just as quickly as leaning on it with both hands.  I don’t mean to stress-test my nice cups, of course, but I did learn something useful.

Also, I spent three hours cleaning my house, and it doesn’t look any different.  Boo?

Finally, hey, Taiwan, how about a USB-powered heated spoon-like device for direct immersion heating of a coffee?  Nudge nudge, guys.

Neutron stars are dead relics that have collapsed into very small, dense spheres with tough crusts. Forces welling from within can crack the crusts during events called star quakes, similar to earthquakes.

The awesome power of those quakes can blast gamma rays into space, leading scientists to suspect that the stars’ crusts must be very hard to break.

A new study suggests how strong they are: The crust of neutron stars could be 10 billion times stronger than steel, based on an innovative model of elements compressed as tightly as they would be on the surface of a neutron star.

In 2004, astronomers spotted a spectacular gamma-ray explosion bursting off a neutron star in the Sagittarius constellation, 50,000 light years from Earth. The star, SGR 1806-20, is a magnetar, a type of neutron star that has a powerful magnetic field. NASA and European satellites and astronomers around the world detected the flare, which for a tenth of a second was brighter than anything ever seen beyond our solar system. It was the biggest such flare ever spotted and one of only four that have been seen so far.

“We think that these giant flares are coming from really, really big star quakes,” said Indiana University physicist Charles Horowitz. Only a super-strong crust could have exploded so forcefully, he explained.

To find out how strong the crusts of neutron stars really are, Horowitz and a colleague created a computer simulation of a star’s surface. Though the interior of the star is a kind of fluid mass of mostly neutrons, the crust is composed of broken-up atoms, the nuclei of unknown elements. To simulate this, Horowitz used the computer program to squeeze together virtual selenium atoms, pressing them into tiny cubes. He determined that the crust is billions of times stronger than even the hardiest metal alloys here on Earth.

“You can’t produce anything like these conditions on Earth, which is why we did not know the strength before,” he said. His results were published May 8 in the journal Physical Review Letters.

…

This next part was my favorite part of the article:

Neutron stars are so dense that if you could dip a teaspoon into one of them and scoop out some of its neutrons the spoon would weigh 100 million tons. If you were to hold that empty teaspoon just one yard above the star’s surface and drop it, it would strike the surface at 4.3 million mph.

via Neutron Star Crust Is Stronger than Steel.

Neutron Star Crust. Great band name.

I have been recently rediscovering my interest in physics theory, in particular quantum physics theory. Now the internet is a treasure trove of interesting bits and bods, for example this blog is fascinating, and I am yet to start exploring off the links. There just isn’t enough time to read everything I want to read…  

¿Qué tienen que ver la fotosíntesis de las plantas y la computación cuántica? Hace ya un par de años que se descubrió que la fotosíntesis logra una eficacia de más del 95% gracias a utilizar un algoritmo de búsqueda cuántico para canalizar la energía. Mientras los físicos se afanan en lograr fabricar el primer ordenador cuántico práctico luchando contra la decoherencia, la Naturaleza, como siempre, muy por delante. ¿Podremos algún día desarrollar una tecnología energética renovable que imite la fontosíntesis de las plantas? Sorprendentemente, para ello necesitamos dominar la computación cuántica. El trabajo de investigación fue desarrollado por el químico teórico Graham Fleming de la University of California at Berkeley y sus colaboradores y nos lo contó, como no, Philip Ball, “Photosynthesis works ‘by quantum computing’,” Chemistry World, May, 2007 . La figura está extraída de “Quantum Secrets Of Photosynthesis Revealed,” Science News, ScienceDaily, Apr. 12, 2007 . También son buenas lecturas Roseanne J. Sension, “Biophysics theory: Quantum path to photosynthesis,” News and Views, Nature 446: 740-741, 12 April 2007 , y el artículo técnico original Gregory S. Engel et al. “Evidence for wave mechanicslike energy transfer through quantum coherence in photosynthetic systems,” Nature 446: 782-786, 12 April 2007 . La idea de que la fotosíntesis opera utilizando la computación cuántica es mucho más antigua (Scott M. Hitchcock, “‘Photosynthetic’ Quantum Computers?,” ArXiv, Submitted on 20 Aug 2001 ).

Los investigadores estudiaron la fotosíntesis en la bacteria fototrópica verde del azufre (Chlorobium tepidum). La fotosíntesis se inicia cuando la luz incidente excita los electrones de los cromóforos (moléculas de pigmentos fotosensibles como la clorofila). Este nivel de energía alto desciende generando una onda encadenada (excitón) que lleva esta energía a través del cromóforo hasta alcanzar un centro químico activo donde queda atrapada y más tarde será utilizada para la fabricación de carbohidratos. El cromóforo actúa como una especie de “antena” para la luz. Los investigadores han utilizado espectroscopia bidimensional basada en la transformada de Fourier y han demostrado que la transferencia de energía dentro del cromóforo es coherente y dura muchísimo (cientos de femtosegundos). Es como sí la energía “visitara” simultáneamente varios caminos posibles y eligiera el óptimo para llegar al centro activo. El proceso es análogo al algoritmo cuántico de Grover, capaz de buscar un elemento en un vector de componentes desordenadas en sólo de pasos. La limitación más importante del estudio es que se han estudiado los cromóforos a baja temperatura (77 ºKelvin). Los autores suponen que el mismo mecanismo ocurre a temperatura ambiente (aunque demostrarlo experimentalmente es mucho más difícil).

Otros artículos sobre computación cuántica en este blog:

Lenguajes de alto nivel para la computación cuántica (o computación cuántica para informáticos) (Publicado por emulenews en Mayo 6, 2008)

Fabricado el primer circuito integrado cuántico aunque sólo de 2 cubits (Publicado el Marzo 12, 2009)

I have so many posts to write, and I keep not writing them.  In the meantime, you can see the videos I made at Hershey Park at our annual physics theory field trip.  I put them on YouTube, where I now have my own “channel” at

http://www.youtube.com/user/WCEastFZX

Here is one of my videos: