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| dlzc... |
 Posted: Thu Nov 05, 2009 10:12 am |
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| Ken S. Tucker... |
| Posted: Thu Nov 05, 2009 12:35 pm |
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On Nov 5, 1:00 pm, Yousuf Khan <bbb... at (no spam) spammenot.yahoo.com> wrote:
[quote]dlzc wrote:
http://www.popsci.com/node/40163/?cmpid=enews110509
David A. Smith
Two different frequencies of Gamma rays arriving 0.9 seconds apart from
the same source could be considered confirmation that the highest energy
GR's /are/ affected by the roughness of space.
Yousuf Khan
[/quote]
The universe is obviously not a perfect vacuum, it has
a density, so just as blue light is slowed more than
red in optics, the 0.9 secs diff makes sense.
Ken |
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| Nick |
| Posted: Thu Nov 05, 2009 12:59 pm |
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Joined: 17 Apr 2005
Posts: 3297
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On Nov 5, 12:12 pm, dlzc <dl... at (no spam) cox.net> wrote:
[quote]http://www.popsci.com/node/40163/?cmpid=enews110509
David A. Smith
[/quote]
What else do you expect? It is a fact smith.
Mitch Raemsch |
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| dlzc... |
| Posted: Thu Nov 05, 2009 3:01 pm |
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Dear Yousuf Khan:
On Nov 5, 2:00 pm, Yousuf Khan <bbb... at (no spam) spammenot.yahoo.com> wrote:
[quote]dlzc wrote:
http://www.popsci.com/node/40163/?cmpid=enews110509
Two different frequencies of Gamma rays arriving 0.9
seconds apart from the same source could be considered
confirmation that the highest energy GR's /are/ affected
by the roughness of space.
[/quote]
Not when the visible light, radio waves, etc. all also arrive during
the same "burst". Bursts are not zero duration events, they
ostensibly also come from distant events so the burst gets "duration
stretched" by expansion, and we still are not clear on mechanism as to
what departs... when.
David A. Smith |
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| Yousuf Khan... |
| Posted: Thu Nov 05, 2009 4:00 pm |
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dlzc wrote:
[quote]http://www.popsci.com/node/40163/?cmpid=enews110509
David A. Smith
[/quote]
Two different frequencies of Gamma rays arriving 0.9 seconds apart from
the same source could be considered confirmation that the highest energy
GR's /are/ affected by the roughness of space.
Yousuf Khan |
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| Tom Roberts... |
| Posted: Thu Nov 05, 2009 4:23 pm |
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Yousuf Khan wrote:
[quote]Two different frequencies of Gamma rays arriving 0.9 seconds apart from
the same source could be considered confirmation that the highest energy
GR's /are/ affected by the roughness of space.
[/quote]
Not when you don't know that the source's duration was significantly
less than 0.9 seconds. They don't know that.
Tom Roberts |
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| Nick |
| Posted: Thu Nov 05, 2009 4:39 pm |
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Joined: 17 Apr 2005
Posts: 3297
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On Nov 5, 5:58 pm, Yousuf Khan <bbb... at (no spam) spammenot.yahoo.com> wrote:
[quote]Tom Roberts wrote:
Yousuf Khan wrote:
Two different frequencies of Gamma rays arriving 0.9 seconds apart
from the same source could be considered confirmation that the highest
energy GR's /are/ affected by the roughness of space.
Not when you don't know that the source's duration was significantly
less than 0.9 seconds. They don't know that.
Then they can't confirm the opposite either.
Yousuf Khan
[/quote]
Space is continuous and curved round in substance. It has no
roughness. |
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| Nick |
| Posted: Thu Nov 05, 2009 6:23 pm |
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Joined: 17 Apr 2005
Posts: 3297
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On Nov 5, 7:14 pm, eric gisse <jowr.pi.nos... at (no spam) gmail.com> wrote:
[quote]Yousuf Khan wrote:
Tom Roberts wrote:
Yousuf Khan wrote:
Two different frequencies of Gamma rays arriving 0.9 seconds apart
from the same source could be considered confirmation that the highest
energy GR's /are/ affected by the roughness of space.
Not when you don't know that the source's duration was significantly
less than 0.9 seconds. They don't know that.
Then they can't confirm the opposite either.
Someone has their thinking cap on today.
Yousuf Khan- Hide quoted text -
- Show quoted text -
[/quote]
Should't light change sizes if it is a local wave?
How could a small energy light with a large wavelength spread out
accros space at emmision? if it is not a local phenomenon?
Mitch Raemsch |
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| Yousuf Khan... |
| Posted: Thu Nov 05, 2009 8:58 pm |
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Tom Roberts wrote:
[quote]Yousuf Khan wrote:
Two different frequencies of Gamma rays arriving 0.9 seconds apart
from the same source could be considered confirmation that the highest
energy GR's /are/ affected by the roughness of space.
Not when you don't know that the source's duration was significantly
less than 0.9 seconds. They don't know that.
[/quote]
Then they can't confirm the opposite either.
Yousuf Khan |
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| eric gisse... |
| Posted: Thu Nov 05, 2009 10:14 pm |
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Guest
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Yousuf Khan wrote:
[quote]Tom Roberts wrote:
Yousuf Khan wrote:
Two different frequencies of Gamma rays arriving 0.9 seconds apart
from the same source could be considered confirmation that the highest
energy GR's /are/ affected by the roughness of space.
Not when you don't know that the source's duration was significantly
less than 0.9 seconds. They don't know that.
Then they can't confirm the opposite either.
[/quote]
Someone has their thinking cap on today.
[quote]
Yousuf Khan[/quote] |
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| Yousuf Khan... |
| Posted: Thu Nov 05, 2009 11:30 pm |
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BURT wrote:
[quote]Should't light change sizes if it is a local wave?
How could a small energy light with a large wavelength spread out
accros space at emmision? if it is not a local phenomenon?
[/quote]
It's individual photons that do the spreading out across space. There is
a different photon for every direction you see in space.
Yousuf Khan |
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| YKhan... |
| Posted: Sat Nov 07, 2009 4:29 am |
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On Nov 5, 8:01 pm, dlzc <dl... at (no spam) cox.net> wrote:
[quote]Two different frequencies of Gamma rays arriving 0.9
seconds apart from the same source could be considered
confirmation that the highest energy GR's /are/ affected
by the roughness of space.
Not when the visible light, radio waves, etc. all also arrive during
the same "burst". Bursts are not zero duration events, they
ostensibly also come from distant events so the burst gets "duration
stretched" by expansion, and we still are not clear on mechanism as to
what departs... when.
[/quote]
So they would need to correlate how quickly the radio, visible, IR,
UV, etc. also came. Since they can't stopwatch individual photons
leaving the GRB at exactly the same time, so they typically have to
correlate the peaks and valleys of each of the signals. If it's
assumed that the same sequence of events within the GRB are causing
the peaks and valleys in all wavelengths of light, then all
wavelengths should be arriving at the same time with a nearly
identical graph. Some events inside the GRB might create more of one
wavelength over another, but they should have their peaks and valleys
at nearly the same times, even if their amplitudes differ.
Yousuf Khan |
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| Ken S. Tucker... |
| Posted: Sat Nov 07, 2009 7:54 am |
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On Nov 7, 6:29 am, YKhan <yjk... at (no spam) gmail.com> wrote:
[quote]On Nov 5, 8:01 pm, dlzc <dl... at (no spam) cox.net> wrote:
Two different frequencies of Gamma rays arriving 0.9
seconds apart from the same source could be considered
confirmation that the highest energy GR's /are/ affected
by the roughness of space.
Not when the visible light, radio waves, etc. all also arrive during
the same "burst". Bursts are not zero duration events, they
ostensibly also come from distant events so the burst gets "duration
stretched" by expansion, and we still are not clear on mechanism as to
what departs... when.
So they would need to correlate how quickly the radio, visible, IR,
UV, etc. also came. Since they can't stopwatch individual photons
leaving the GRB at exactly the same time, so they typically have to
correlate the peaks and valleys of each of the signals. If it's
assumed that the same sequence of events within the GRB are causing
the peaks and valleys in all wavelengths of light, then all
wavelengths should be arriving at the same time with a nearly
identical graph. Some events inside the GRB might create more of one
wavelength over another, but they should have their peaks and valleys
at nearly the same times, even if their amplitudes differ.
Yousuf Khan
[/quote]
Yeah, but it's hard to draw conclusions. Perhaps the
dynamics of the GRB event involved a low energy initiator
that took 0.9 secs to set-off the higher energy spike.
Personally I think there should be a slight diff in the
speeds of light as a function of energy since the universe
is not a perfect vacuum for which the 'constant speed of
light' is specified.
Perhaps the diff could co-related with the density of
our part of the universe.
Regards
Ken S. Tucker |
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| dlzc... |
| Posted: Sat Nov 07, 2009 10:22 am |
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Dear YKhan:
On Nov 7, 7:29 am, YKhan <yjk... at (no spam) gmail.com> wrote:
....
[quote]So they would need to correlate how quickly the
radio, visible, IR, UV, etc. also came.
[/quote]
Right. For different GRB events, and different distances, there
should be similarity in arrival times (if similar physical events
caused them).
[quote]Since they can't stopwatch individual photons
leaving the GRB at exactly the same time, so they
typically have to correlate the peaks and valleys
of each of the signals. If it's assumed that the
same sequence of events within the GRB are
causing the peaks and valleys in all wavelengths of
light, then all wavelengths should be arriving at the
same time with a nearly identical graph.
[/quote]
Which is what they seem to be saying, regardless of GRB source
distance.
[quote]Some events inside the GRB might create more of
one wavelength over another, but they should have
their peaks and valleys at nearly the same times,
even if their amplitudes differ.
[/quote]
*If* the physics is similar...
David A. Smith |
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| Yousuf Khan... |
| Posted: Tue Nov 10, 2009 1:35 am |
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Ken S. Tucker wrote:
[quote]Yeah, but it's hard to draw conclusions. Perhaps the
dynamics of the GRB event involved a low energy initiator
that took 0.9 secs to set-off the higher energy spike.
[/quote]
Understood but that by definition would be a one-time only event, since
it is an "initiator", and therefore it can be discarded. All subsequent
events should be synchronized throughout the spectrum.
[quote]Personally I think there should be a slight diff in the
speeds of light as a function of energy since the universe
is not a perfect vacuum for which the 'constant speed of
light' is specified.
[/quote]
Well in a way, that was sort of the point of trying to measure the speed
difference. If the shortest wavelength photons begin to feel the quantum
foam of space, then they should be slowed down. Then the vacuum of space
itself would be a something rather than a nothing, therefore it wouldn't
really be a vacuum.
[quote]Perhaps the diff could co-related with the density of
our part of the universe.
Regards
Ken S. Tucker
[/quote]
Apparently this supernova was instrumental in ruling out a particular
class of quantum gravity theories, but doesn't rule out other classes of
quantum gravities. So they are not denying that there is a delay in the
arrival of higher-energy, shorter-wavelength gamma rays.
Quantum gravity theories wiped out by a gamma ray burst - Ars Technica
"A value this close to the Planck length means that quantum gravity
models in which there's a linear relationship between photon energy and
speed are "highly implausible." That leaves other quantum gravity
options open, including those in which the the relationship is
non-linear. Hopefully, theoreticians will be able to devise real-world
tests for some of these. "
http://arstechnica.com/science/news/2009/10/quantum-gravity-theories-meet-a-gamma-ray-burst.ars
Yousuf Khan |
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