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CraigS
09-08-2011, 09:40 AM
Beyond space-time: Welcome to phase space (http://www.newscientist.com/article/mg21128241.700-beyond-spacetime-welcome-to-phase-space.html?page=1)


Seems the technique is somewhat akin to what Witten did to unify competing String Theories, which was akin to what Einstein did to move things along from Newtonian models .. ie: move thinking towards higher dimensions.

The Cosmological Principle, at the end of the day, is a working assumption which provides the fundamental basis for Standard Cosmology with all of its strengths and weaknesses. Is this really the way nature works ? Why should we presume it is necessarily this way ? :question:

Cheers

renormalised
09-08-2011, 01:58 PM
That was in the latest New Scientist. Bought it yesterday but haven't got up to this story....looks interesting.

BTW....what happened to your Calabi Yau manifold and Witten's Hamster??. Have you just become too chaotic:):P:P

CraigS
09-08-2011, 02:04 PM
Captain Chaos strikes again ! .. Quite unstable, really :P :)

Thought the new Avatar might be appropriate to this thread, given that it is about migrating our thinking to phase-space …

(but .. then again, I might be wrong :) )

Cheers

renormalised
09-08-2011, 02:20 PM
Where's Agent 86 when you need him:):P

CraigS
09-08-2011, 03:59 PM
Its interesting to note that it has been confirmed that high energy photons from a GRB (Gamma Ray Burst) have been observed to arrive ahead of lower energy photons.

This is predicted in Smolin's theory, as momentum space is curved (ie: 'non-metric').

Mind you, they go on to explain that this can also be explained simply by the way they're emitted from the source .. ie: the explosions aren't instantaneous .. they last for several seconds, which would account for the observed delays.

More GRBs are needed in order to pin this one down ..

.. interesting

Cheers

CraigS
09-08-2011, 04:24 PM
For anyone interested, 'Phase Space' can be easily described by a simple moving pendulum. You could plot its height above the ground on the y-axis, and its position either side of the centre along the x-axis (you'd end up drawing an arc of a circle).

To get the phase-space, you could also plot its horizontal position (over time) on the x-axis, and its velocity along the y-axis. This ends up as a (sort of) ellipse.

Here's a good animation (http://en.wikipedia.org/wiki/Pendulum_(mathematics)#Examples) showing some phase diagrams of a pendulum in motion.

Cheers

xelasnave
09-08-2011, 04:37 PM
Well I am interested for one Craig.
If I retain 1% of all I have been reading I will be 100% ahead of where I came from:D.
Thank you I appreciate it greatly:thumbsup:.

alex:):):)

renormalised
09-08-2011, 05:35 PM
The other explanation also has to do with the graininess of spacetime and how the gamma rays emitted from the GRB interact with spacetime in their journey to the detectors.

In any case, the emission mechanism could easily explain why, as they have mentioned. The more powerful gamma rays are emitted during the peak of the explosion, with the weaker gamma rays being emitted during the tailing off of the explosion.

irwjager
09-08-2011, 05:45 PM
From the article;
So, at the end of the observation, how can we guarantee we were actually even there to commence observing the location of the elephant to begin with? Does the initial location of the observer not become fuzzed as well in retrospect?
Following that line of thought, should we then not accept that, in this case, observing something over time causes a growing uncertainty about not only the location of the observed object, but also the validity/calibration (any attribute inherent to location) of the observer's measurement device/eyes/experimental setup/question? How can we be sure that, in retrospect, we created the right conditions to commence our observations to begin with?

Maybe I'm dribbling here, but it's mind blowing stuff regardless!

CraigS
09-08-2011, 06:14 PM
Hi Ivo;
Hmm .. there is one invariant though 8d phase space.
If your observation is made in consideration of, and optmised in consideration of all 8 dimensions, then are we not back to the old invariant space-time perspective ?
Perhaps I'm dribbling more than yourself .. I'm still trying to wrap my mind around the concept let alone the ramifications.
:)
Cheers

CraigS
10-08-2011, 08:45 AM
Its interesting that they also predict another effect which results from torsion induced by momentum phase space called 'dual gravitational lensing' from their paper: Gamma ray burst delay times probe the geometry of momentum space (Mar 2011): (http://arxiv.org/pdf/1103.5626v1)



There's quite a lot of thinking that's gone into all this.

The other key paper behind it all is: The principle of relative locality (Jan 2011). (http://arxiv.org/PS_cache/arxiv/pdf/1101/1101.0931v2.pdf)

Cheers