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Superprincipia's Blog | Physics of the Future Today! Cuentos Cuánticos | Un sitio donde los cuentos de ciencia están contados y no contados al mismo tiempo. Enlaces de Cosmología. Wilkinson Microwave Anisotropy Probe (WMAP) Antares - Observatorio Virtual - P01 : Guía de aprendizaje. El observatorio Virtual pretende simular la observación astronómica desde los distintos telescopios que constituyen el llamado Observatorio de La Silla en Chile, perteneciente al European Southern Observatory. En la imagen aérea del observatorio tenemos una visión panorámica de los telescopios disponibles. Si movemos el ratón sobre las diferentes cúpulas, un texto emergente nos indicará a qué telescopio corresponde cada una de ellas. Por necesitar un instrumento determinado, cada práctica concreta sólo puede realizarse con un telescopio determinado. Aunque el guión de la práctica nos indica claramente cual es ese telescopio e instrumento, la imagen general sólo nos permitirá seleccionar el telescopio adecuado.

Si seleccionamos otro cualquiera, recibiremos un mensaje como el de la figura Fig. 2 Fig. 2 Existe un telescopio en nuestro observatorio que no es utilizado en ninguna práctica. Fig. 3. THE EINSTEIN EQUATIONS. Expo/Science & Industry/Spacetime Wrinkles | Forward | Back | Up | Map | Glossary | Information | Larry Smarr, NCSA/Univ. of Illinois, on-camera QuickTime Movie (2.3 MB); Sound File (1.6 MB); Text Introduction The Symbolic Form Spherical Symmetry Axisymmetry Full Generality Beyond the Math Introduction When expressed mathematically, Einstein's gravitation theory yields a set of formulas known collectively as the Einstein Field Equations.

However, applying the equations is no easy task. After he published his famous paper in 1916, Einstein later conceded that the mathematical difficulties of his General Theory of Relativity were a "very serious" impediment to its further development. Ed Seidel, NCSA/Univ. of Illinois, on-camera QuickTime Movie (1.2 MB); Sound File (788K); Text The Symbolic Form QuickTime Movie (1.8 MB); Sound File (961K); Text Spherical Symmetry The first person to apply Einstein's general theory was the German astrophysicist Karl Schwarzschild. Axisymmetry Einstein Equations in 2D. John Baez's Stuff. This Week's Finds - Latest Edition Fun Stuff Serious Stuff Talks Seminar Diary Twitter Google+ Azimuth Blog Azimuth Project Visual Insight n-Category Café Physics FAQ I'm a mathematical physicist. I work at the math department at U. C.

Riverside in California, and also at the Centre for Quantum Technologies in Singapore. I'm working on network theory, information theory, and the Azimuth Project, which is a way for scientists, engineers and mathematicians to do something about the global ecological crisis. If you want to help save the planet, please send me an email or say hi on my blog. What's New? I'm helping run a new journal on applied category theory. Check out my free online course on applied category theory! Together with three students at Applied Category Theory 2018, I wrote a paper on biochemical coupling through emergent conservation laws.

Learn about quantum mechanics and the dodecahedron: These posts lead up to a grand conclusion: the Kepler problem and the 600-cell! La constante cosmológica. Pero, ¡¿cómo puede el vacío pesar algo?!. Si tenemos un pistón "lleno de vacío" y tiramos del émbolo, crearemos más vacío que por tanto contendrá una mayor "energía de vacío" que sólo habrá podido ser suplida por la fuerza que movió el pistón. En el proceso, la densidad de energía de vacío debe ser por supuesto una constante, puesto que no puede depender de ningún parámetro, ya que en el vacío ¡no hay nada de lo que pueda depender!. Cuando hacemos el experimento más habitual con un gas en el interior del pistón, baja la presión del gas. En este proceso "bajar la presión" implica enfriamiento y por tanto "disminución de la energía interna del gas". La presión relativista en este caso se puede calcular como (demostración) P = - rvacíoc2 Donde r vacíoes la densidad de masa del vacío calculada a partir de la relación relativista E = m c2 Pero en Relatividad General, la energía tiene "peso" y por tanto la presión.

G = 4/3 p G (rmateria+rvacío+ 3 P/c2) R -2 r vacío = 0.5 r materia Sistema Solar 1. SHTOOLS - Tools for working with spherical harmonics. The current version of SHTOOLS is 2.1 (released October 20, 2006) What is SHTOOLS? SHTOOLS is an archive of fortran 95 based software that can be used to perform (among others) spherical harmonic transforms and reconstructions, rotations of spherical harmonic coefficients, and multitaper spectral analyses on the sphere. What makes SHTOOLS different? While several collections of code currently exist for working with data expressed in spherical harmonics, this one is unique for several reasons: It can accommodate any standard normalization of the spherical harmonic functions, including the "Geodesy" 4π normalized, orthonormalized, Schmidt semi-normalized, and unnormalized harmonics.

Spherical harmonic transforms can be calculated by exact quadrature rules using either (1) the sampling theorem of Driscoll and Heally (1994) where data are equally sampled (or spaced) in latitude and longitude, or (2) Gauss-Legendre quadrature. How do I use SHTOOLS? How much does it cost? Spherical Harmonic Models of Planetary Topography. Cosmology. PHYS591: Theories of Gravitation. PHYSICS, RELATIVITY, GRAVITATION, COSMOLOGY AND MATHEMATICS - NEW THEORIES AND FORMULATIONS. Kepler's laws of planetary motion. In astronomy, Kepler's laws of planetary motion are three scientific laws describing the motion of planets around the Sun. Kepler's laws are now traditionally enumerated in this way: Figure 1: Illustration of Kepler's three laws with two planetary orbits. (1) The orbits are ellipses, with focal points ƒ1 and ƒ2 for the first planet and ƒ1 and ƒ3 for the second planet.

The Sun is placed in focal point ƒ1. (2) The two shaded sectors A1 and A2 have the same surface area and the time for planet 1 to cover segment A1 is equal to the time to cover segment A2. (3) The total orbit times for planet 1 and planet 2 have a ratio a13/2 : a23/2. Most planetary orbits are almost circles, so it is not apparent that they are actually ellipses. Isaac Newton showed in 1687 that relationships like Kepler's would apply in the solar system to a good approximation, as consequences of his own laws of motion and law of universal gravitation. Nomenclature[edit] History[edit] First law[edit] Second law[edit] and height. NGDC Geomagnetic Calculators. Relativity. Lunar Sinuous Rilles Atlas. The Atlas of Lunar Sinuous Rilles is a comprehensive collection of images of 195 lunar sinuous rilles that are globally distributed around the Moon. The interface for the atlas, seen below, contains red circles that represent the source locations of each sinuous rille.

Sinuous rilles are identified with numbers that correlate with a matching set of numbers in a database accessible at a link below. The atlas allows the user to zoom into the sinuous rille of interest by centering the region of interest on the screen and scrolling the mouse wheel or clicking shift on the keyboard (click control to zoom out). Alternatively, the user can select the sinuous rille of interest by number from the drop-down menu at the top right of the Lunar Reconnaissance Orbiter Camera’s (LROC) Wide Angle Camera (WAC) image mosaic. Reference: Hurwitz, D. M., J. W. Apollo Image Atlas, 70mm Hasselblad Image Catalog. The Exploration of the Earth's Magnetosphere" Relativity. An Atlas of The Universe. De Astronomos a Astronaves. SIMBAD Astronomical Database. What is SIMBAD, and what is it not ? % The purpose of Simbad is to provide information on astronomical objects of interest which have been studied in scientific articles.

Simbad is a dynamic database, updated every working day. It provides the bibliography, as well as available basic information such as the nature of the object, its coordinates, magnitudes, proper motions and parallax, velocity/redshift, size, spectral or morphological type, and the multitude of names (identifiers) given in the literature. The CDS team also performs cross-identifications based on the compatibility of several parameters, in the limit of a reasonably good astrometry. Simbad is a meta-compilation built from what is published in the literature, and from our expertise on cross-identifications. Simbad is not a catalogue, and should not be used as a catalogue.

Michael Nauenberg Homepage. Links - Navigational Algorithms. Topographical Engineers -- Jupiter's Moons. SJAA | San Jose Astronomical Association. Determine Your Longitude With Jupiter's Moons. It was MIT physicist Philip Morrison on a television documentary who taught me how to use Jupiter's moons as a system for synchronizing clocks, the first step in calculating longitude with astronomical observations. With an ephemeris for Jupiter satellite transits and occultations that is accurate for the time at the Royal Greenwich Observatory, you can synchronize your clock to the observatory's by watching the scheduled event.

The difference between your local time and Greenwich local time reveals your longitude. On a clear night in late February, I decided to try this experiment. I set up my 4-inch refractor on my back deck outside my house in San Rafael, California. My favorite Jupiter ephemeris (www.projectpluto.com/jevent.htm) predicted an occultation of Europa for 0510 Greenwich Mean Time (GMT) the following day, or 9:10 p.m. Pacific Standard Time, my local "standard" clock. These days it's easy to set your watch to GMT. Finally it was clear that nothing was left. UNL Astronomy Education. Celestial Sphere. Previous Programmes. Ephemerids. Home. Astronomy Pages.