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Space Science

Measuring the Hubble Constant Better 102

eldavojohn writes "The Hubble Constant is used for many things in astrophysics: from determining how fast things are moving away from us, to the total volume of the universe, to predicting how our universe will end. The current best value for the Hubble Constant is 74.2 ± 3.6 (km/s)/Mpc according to recent conventional methods and the recently restored Hubble Telescope. Most astronomers agree that that's within 10% of its actual value. Researchers now claim that they might be able to get to 3% using water molecules in galactic disks to act as masers that amplify radio waves, to analyze galaxies seven times as far away as the current measurements. The further away the 'standard candle' is, the more assured they can be that local effects are not skewing the measurements. From one of the researchers: 'We measured a direct, geometric distance to the galaxy, independent of the complications and assumptions inherent in other techniques. The measurement highlights a valuable method that can be used to determine the local expansion rate of the universe, which is essential in our quest to find the nature of dark energy.' Once the Square Kilometer Array is completed, they hope to get even closer to the actual value."
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Measuring the Hubble Constant Better

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  • by Yokaze ( 70883 ) on Tuesday June 09, 2009 @03:27PM (#28270233)

    AFAIK, the universe is not infinite in size, it is just infinite. The very same way a circle is infinite, but has a length, or a ball or torus a surface.

  • by cheftw ( 996831 ) on Tuesday June 09, 2009 @05:36PM (#28271981)

    It tells you everything. Multiply it by a distance - you get a speed. Way more useful than the other one IMHO.

  • Re:Bad Labrador (Score:2, Insightful)

    by anarchyboy ( 720565 ) on Tuesday June 09, 2009 @06:53PM (#28272777)
    Why not? If he's theory is right surely that would be a good thing? interestingly I read the book you linked to and found it quite hard going, there was little explanation of the ideas presented and seemed to have many descriptive quotes from people like minkowski that were then interpruted, woryingly these 'sound bites' were offered as support of the theory presented.

    The multi-dimensional description of time was woefully under explained, probably due to a lack of a concise mathematical description but was instead given a more general description. As a physicist I have a precise understanding of what the space time of general relativity is mathematicaly the physical interperation can be tricky at times and the mathematics hard but it is very well defined and unfortunatly the link you gave did not furnish me with the similar well defined mathematical description of the Mayer's theory.

    I would be interested to see a derivation of some known results from GR or newtonian gravity and from cosmology, reproduced in Mayer's frame work as this would provide a good starting point from which to understand the theory. Just in case you are interested I would like to see how the theory reproduces orbital trajectories (ie keplers laws), The equivalent description of the CMB would also be usefull. I may just me being lazy but as you've probably guessed I'm not overly impressed so far.

    What really ticked the 'crackpot' box for me though was the single publication, proclaimed as a revolution of great importance. I would like to include a quote but it appears i can't copy and paste it so just read the last paragraph on page 136. Such a statement really has no place in a scientific document and is really indicative of the entire document

Make it myself? But I'm a physical organic chemist!