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Arch2008

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Everything posted by Arch2008

  1. If I understand you correctly, then you have a starting mass1 which undergoes some unspecified process to radiate energy in the electromagnetic spectrum and becomes mass2. To better elaborate this relationship, I might use terms like mass1 and something like mass1’ (mass1 prime). Other than that, it looks okay to me.
  2. Objects in the universe, like stars, convert matter into energy that gets radiated into space. Matter with mass X is converted into energy with mass X. If you took an arbitrary mass for a star and calculated the average mass of a galaxy then you could approximate the mass of one hundred billion galaxies to get the mass of the observable universe. (This might be approximately something like 10^11 solar masses squared or 10^22 solar masses) However, the total universe (the observable plus whatever else there is) is a closed system. The energy in the total universe is not radiated into something else, i.e., the universe is everything. So the mass of the total universe stays the same and does not decrease.
  3. Here's a link to Wolf-Rayet stars which are the culprit in hypernovae, with further links. http://en.wikipedia.org/wiki/Wolf%E2%80%93Rayet_star These stars are really rare (only a few hundred in the galaxy). I recall that I did a post about the pair instability mechanism about a year ago.
  4. When a star fuses iron, it takes more energy than is released from the fusion. So the star essentially reaches a dead end by making iron. When the core loses energy to make iron it cools. Then gravity is no longer balanced by thermal energy being radiated from the core, so the outer layers of the star collapse at something like a quarter of the speed of light. These outer layers then crash into the core. The core is compressed and the outer layers reverberate, causing the star to rip itself apart. Sometimes, supermassive stars undergo matter-antimatter chain reactions in its core that totally destroy the star in what has been called a hypernova.
  5. Well a GRB does have opposing jets like a pulsar, so it would do the most damage if “aimed at us”. Usually, it must be within 1000 light years to cause extinction type damage, too, but I suppose that would be dependent on how energetic it is. http://www.nasa.gov/mission_pages/GLAST/news/high_grb.html
  6. The anti-matter clouds in the article are actually opposing jets produced by overflow from the accretion disk pouring in to the black hole. More matter is trying to cross the event horizon than is physically possible, so the “run off” particles get accelerated to near light speed by the magnetic field of the BH and this creates anti-matter particles. Anti-matter is like matter, except that its charge is totally opposite. Since certain BH’s have a magnetic charge, anti-matter may be attracted to BH’s more so than matter. However, the current theory is that a tiny number of anti-matter particles eventually decay into matter particles in what I believe is called charge-parity violation. However, we really just don’t know for sure.
  7. Last week I was watching the LHC at this screen: http://lhc.web.cern.ch/lhc/ when something happened and there was a shutdown. In the “Comments” section at lower screen right, someone had entered “UFINO?” as a possible explanation for the shutdown. Is this shorthand for unidentified SUSY particle (of course ending in INO)? I googled UFINO without any explanation.
  8. http://history.nasa.gov/spaceweek.html http://www.worldspaceweek.org/ http://www.worldspaceweek.org/calendar_2010.php?NOF_StartRow_EventLocationsAndNames2010_Iterator=271 Perhaps something is happening near you.
  9. Here are some 1st reports from the Herschel space observatory: http://herschel.cf.ac.uk/news/herschel-reveals-stellar-surprises-and-galaxies-galore Merged post follows: Consecutive posts mergedAt another forum, a member of the ESA told me that they were terribly disappointed with this press release. It contains a lot of erroneous info and should probably just be ignored.
  10. Do you mean this? http://news.nationalgeographic.com/news/2009/11/091106-new-supernova-type.html If by “would it be possible that some of these supernovas that're weaker that regular ones have happened further than 13.7B light years away” you mean could stars have existed more than 13.7 bya, then the answer is no. We don’t have to subject the age of the universe to belief or assumption. We know it. Check out the timeline of the universe from WMAP. http://map.gsfc.nasa.gov/news/5yr_release.html
  11. You might have more luck here than at the Huffington-Post: http://lhc.web.cern.ch/lhc/ Now that the media event is over, the day-to-day work continues.
  12. Matter and energy are the same thing. Both have the property of mass. If the Sun collapsed to a singularity, the singularity would have the mass of the Sun. So mass is not converted to energy. If you mean that the Sun emits gravitational waves, then the singularity would emit the same waves. There would be no perturbation in the Earth’s orbit. As to gravity waves between something like merging black holes, there is no evidence of this, so no “inescapable conclusion” there.
  13. You might want to start here: http://en.wikipedia.org/wiki/Black_hole The typical 3-D cube plus time is frame dragged so that all vectors, to include time, point to the singularity.
  14. Well one conventional view is that the spinning star collapses first into a sort of torus and then the torus further pancakes down to a spinning Kerr ring singularity (KRS). So the “z” or height axis ”is reduced” as anything perpendicular to the plane of the KRS is crushed flat by gravity. Also, I believe that time becomes a spatial dimension inside the Event Horizon and isn’t “reduced”.
  15. After core fusion reaches iron, it’s the mass of the outer layers of the star imploding at about a quarter of the speed of light that causes the “spatial contraction” and the singularity may be a point.
  16. "derive your red shit" Hmmm...Freudian slip?
  17. Yep. Due to time dilation, the mass accelerated to c takes forever to reach the center to an observer outside the event horizon. So it is “plastered” to the surface region of the black hole (so that its information is not lost to the universe) and again does not really add to an ad hoc “density of the black hole”.
  18. No one will ever “know” what goes on inside the event horizon. We have mathematical models of the universe that are proven that point to singularities and we have research models that are really interesting that point elsewhere but lack that proof thing. Roy Kerr used the proven mathematical model of General Relativity to show how the mass of the collapsing, spinning star becomes a ring with no height and hence a volume of zero with infinite density. When a massive star collapses to a volume denser than a neutron star then space time itself gets ripped and you get an event horizon around “something”. So what is the density of this black hole minus its former collapsar? Zero. The stellar “remnant” had all of the mass and the rest of the “volume” of the black hole had none of it. Space time within the black hole itself gets twisted. To say that the volume of the black hole is X is thus also a misnomer. The last time I checked, really great research gets trumped by proven theory.
  19. The least massive and the most massive black hole singularities all have infinite density. The Wiki statement about black holes having the density of water is an invalid abstraction. When more matter is forced into the event horizon than can enter the black hole the run off is twisted by magnetic fields into opposing jets. This is not material from inside the black hole. SMBHs do not recycle matter. This is a misconception that proponents of the steady state theory use (misuse).
  20. NASA has imaged an accretion disk around a suspected black hole and confirmed that the disk was spinning in such a way that the singularity must also be spinning. Single points do not exhibit spin.
  21. A black hole singularity has zero volume and therefore infinite density (density is mass divided by volume). This is because stars spin and when they collapse their mass spins down into the singularity like water going down a drain. The spin property, called angular momentum cannot be lost. So a spinning singularity is actually an infinitesimal ring (called a Kerr Ring Singularity after the fellow who figured this out) with length and width but no height. It is squashed absolutely flat (height of zero, hence the volume of zero) by its mass. P.S.-I believe that someone at wikipedia has taken the volume of the space inside the event horizon and confused this with the volume of a black hole. This of course is very obtuse, as the mass of the singularity is not evenly spread throughout this volume.
  22. Most of the stars within like 25 ly are "M" class dwarf stars. IIRC, this is the class of so-called red dwarf stars.
  23. Apparently, during a Martian winter, sand particles can get stuck together and frozen carbon dioxide will cover them making a sort of "forest" from these structures. http://www.bild.de/BILD/news/2010/01/13/nasa-fotografiert/doch-sind-das-wirklich-baeume-auf-dem-mars.html
  24. No, these are new exoplanets that were confirmed by ground observatories after Kepler detected them. Merged post follows: Consecutive posts mergedP.S. Eight more exoplanets from sources other than Kepler were added today. http://planetquest.jpl.nasa.gov/atlas/atlas_search.cfm?&Sort=DiscDate&SortDir=DESC
  25. Spirit is apparently stuck in a sandy bit of Martian soil: http://marsrovers.jpl.nasa.gov/newsroom/pressreleases/20091231a.html Dust may continue to accumulate on its solar panel while it is stuck, until it no longer functions.
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