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Space Science

BOSS: The Universe's Most Precise Measurement 128

Cazekiel writes "Observing the primordial sound waves created 30,000 years after the Big Bang, physicists on the Baryon Oscillation Spectroscopic Survey have determined our universe's most precise measurements: 13.5 billion years old. The article detailing the study reports: '"We've made precision measurements of the large-scale structure of the universe five to seven billion years ago — the best measure yet of the size of anything outside the Milky Way," says David Schlegel of the Physics Division at the U.S. Department of Energy's Lawrence Berkeley National Laboratory, BOSS's principal investigator. "We're pushing out to the distances when dark energy turned on, where we can start to do experiments to find out what's causing accelerating expansion."'"
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BOSS: The Universe's Most Precise Measurement

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  • by s.petry ( 762400 ) on Monday April 09, 2012 @07:52PM (#39625233)

    While this project may yield a lot of data it still won't be able to answer most of the fundamental questions. I know they have to advertise that way in order to receive sponsorship and grants, but dang it I'm tired of hearing it.

    We still won't have a clue about what Dark matter is, or even if it exists. It's still a hypothesis that makes big bang models work and gives us the idea that we understand gravity.

    We still won't know what the Universe was just before the big bang, or what caused it.

    Cool, but I'll ignore the hype.

  • by Rei ( 128717 ) on Monday April 09, 2012 @09:44PM (#39626183) Homepage

    Personally, I like to view the expansion of the universe as simply a reduction in the Planck length/time relative to C. This would create the perception of a force pushing everything apart (light taking increasingly long, in terms of Planck units, to travel from one point to another). Ultimately, it's just a different perspective on the same thing, but I like it because it doesn't require the conception of some sort of mysterious "dark energy" -- just an explanation of why the Planck length would slowly shift.

    And I find that, too, rather simple to envision, in a number of ways. For example, one that I've been thinking about recently is that if you view the universe in terms of information processing, the distance-limited interactions like the strong force decline in frequency as the universe ages. So if there's a fixed "processing power" of the whole universe but a decreasing number of "calculations" per "unit" time, then the number of steps per "unit" time increases, which could be expressed in any number of ways toward the universe's physical constants.

  • by KlomDark ( 6370 ) on Monday April 09, 2012 @11:48PM (#39626931) Homepage Journal

    It's pretty obvious, just people aren't thinking about it from the right mindset:

    It has to do with the expansion of outer shell of the edge the remnants of the original big bang explosion; It's really a type of a 'less resistance' problem, like as if something like air resistance gets less as the perimeter of the expanding explosion moves out, yet the mass of the universe remains the same. [Although that explanation ignores the fact that there's not a whole lot of air in space, but bear with me.]

    Although it's not a normal resistance issue like the basic effect of wind resistance, it is different but similar enough to make the full point of view as follows:

    Sort of easy to describe using an analogy of a balloon inside of a large bell jar. Normally, when you blow up a balloon, the air pressure increases as the balloon expands, since it's the increasing air pressure inside the balloon which is causing the expansion.

    But in this case, blow the balloon up halfway, tie it, and seal it inside of the bell jar. Now you sharply/quickly reduce the air pressure in the bell jar by somehow removing a volume of air that is just less than it will take to pop the balloon by over-expansion as the air pressure drops. (Not sure of the math to determine that amount, just would have to experiment with a few balloons to get it right. It's not important to get it at the edge of popping, it's really what goes on inside the balloon while it's being inflated so quickly, yet this time with air pressure decreasing rapidly as it expands rapidly.

      With the impetus coming this time from the outside of the balloon with the bell jar causing a sudden 'vacuum' (Violent loss of pressure actually, not a true vacuum.) implosion around the balloon instead of increasing the pressure on the inside of the the balloon. With the sudden change in outside air pressure, due to the elasticity of the air inside the balloon it would cause a donut-shaped compression wave to (Is there a word for three-dimensional equivalent of the act of traveling from the outer to inner rings of a set of two-dimensional concentric circles?) intensify as it shrank to a more and more compact size, then impacting itself as it reached the absolute center of the balloon, causing it to violently bounce as a shock wave radiating outward to the edge of the balloon, where it's energy would suddenly press against the edge (Yet the force of the sudden re-expansion will cause a 'vacuum ball' of lower pressure in the center of the balloon caused by the bounce causing a lot of air particles in the center to bounce out with the shock wave as they attempt to reclaim the natural equilibrium between air particles), causing it to expand a bit as the rubber/latex gives way a bit (Yet still not popping) and then de-expanding (starting to shrink) as the energy of the shock wave is spent fighting the elasticity of the balloon's edge and then loses.

    Next we get it in reverse, and over and over until all the energy from that initial shock of 'vacuum' has been converted to friction/heat. But that entire process of bouncing is still not the part we are focusing on, but we're nearly to the end of this long explanation:

    Now think of the particles of air inside the balloon, and how they would react as to their average distance between particles, both expanding and compressing. During the phase where the shock wave is expanding back out after it's first collision with the center, about halfway between the center and the edge of the balloon - the energy of the shock wave has already caused some of the inner air particles to begin traveling outward and gaining some inertia. While at the same time, the edge of the balloon is still rapidly receding as it expands due to the 'outer vacuum' of the bell jar still loosing pressure and 'sucking' the balloon larger.

    So this sets the particles moving outwards, and if you do the math - all particles are moving away from each other at an increasing speed, just like the particles/energy of the universe are doing as it expands outwards from the core of the big bang explosion.

  • by Anonymous Coward on Tuesday April 10, 2012 @12:47AM (#39627297)
    If the Planck length were changing with respect to c, such that Planck's constant was changing with respect to c, you would be seeing the effects of changes to things like the fine structure constant and Rydberg constant, which would easily be visible spectroscopically over great distances.

If I had only known, I would have been a locksmith. -- Albert Einstein