Discovery that quasars don't show time dilation mystifies astronomers

Physorg ^ | 09 March 2010 | Lisa Zyga

[Lorianne]

The phenomenon of time dilation is a strange yet experimentally confirmed effect of relativity theory. One of its implications is that events occurring in distant parts of the universe should appear to occur more slowly than events located closer to us. For example, when observing supernovae, scientists have found that distant explosions seem to fade more slowly than the quickly-fading nearby supernovae.

The effect can be explained because (1) the speed of light is a constant (independent of how fast a light source is moving toward or away from an observer) and (2) the universe is expanding at an accelerating rate, which causes light from distant objects to redshift (i.e. the wavelengths to become longer) in relation to how far away the objects are from observers on Earth. In other words, as space expands, the interval between light pulses also lengthens. Since expansion occurs throughout the universe, it seems that time dilation should be a property of the universe that holds true everywhere, regardless of the specific object or event being observed. However, a new study has found that this doesn’t seem to be the case - quasars, it seems, give off light pulses at the same rate no matter their distance from the Earth, without a hint of time dilation.

Astronomer Mike Hawkins from the Royal Observatory in Edinburgh came to this conclusion after looking at nearly 900 quasars over periods of up to 28 years. When comparing the light patterns of quasars located about 6 billion light years from us and those located 10 billion light years away, he was surprised to find that the light signatures of the two samples were exactly the same. If these quasars were like the previously observed supernovae, an observer would expect to see longer, “stretched” timescales for the distant, “stretched” high-redshift quasars. But even though the distant quasars were more strongly redshifted than the closer quasars, there was no difference in the time it took the light to reach Earth.

This quasar conundrum doesn’t seem to have an obvious explanation, although Hawkins has a few ideas. For some background, quasars are extreme objects in many ways: they are the most luminous and energetic objects known in the universe, and also one of the most distant (and thus, oldest) known objects. Officially called “quasi-stellar radio sources,” quasars are dense regions surrounding the central supermassive black holes in the centers of massive galaxies. They feed off an accretion disc that surrounds each black hole, which powers the quasars’ extreme luminosity and makes them visible to Earth.

One of Hawkins’ possible explanations for quasars’ lack of time dilation is that light from the quasars is being bent by black holes scattered throughout the universe. These black holes, which may have formed shortly after the big bang, would have a gravitational distortion that affects the time dilation of distant quasars. However, this idea of “gravitational microlensing” is a controversial suggestion, as it requires that there be enough black holes to account for all of the universe’s dark matter. As Hawkins explains, most physicists predict that dark matter consists of undiscovered subatomic particles rather than primordial black holes.

There’s also a possibility that the explanation could be even more far-reaching, such as that the universe is not expanding and that the big bang theory is wrong. Or, quasars may not be located at the distances indicated by their redshifts, although this suggestion has previously been discredited. Although these explanations are controversial, Hawkins plans to continue investigating the quasar mystery, and maybe solve a few other problems along the way.

Hawkins’ paper will be published in an upcoming issue of the Monthly Notices of the Royal Astronomical Society.

More info: http://www3.interscience.wiley.com/journal/123345710/abstract?CRETRY=1&SRETRY=0

[ETL]

Looks like you were right! The gravitational effects win out over the opposing effects due to the high speed of the satellite.

“the relativistic time slowing due to the speed of the satellite of about 1 part in 1010, the gravitational time dilation that makes a satellite run about 5 parts in 1010 faster than an Earth based clock”

http://en.wikipedia.org/wiki/Global_Positioning_System#Relativity

[Alamo-Girl]

Thank you so very much for sharing your insights, dearest sister in Christ, and thank you for graphic and the fascinating excerpt!

I particularly like this:

The thought that the relation between mind and the world is something fundamental makes many people in this day and age nervous. I believe this is one manifestation of a fear of religion which has large and often pernicious consequences for modern intellectual life.

And I for one see man as a steward only. Man never truly "owns" anything.

The earth [is] the LORD'S, and the fulness thereof; the world, and they that dwell therein. - Psalms 24:1

Is it not lawful for me to do what I will with mine own? Is thine eye evil, because I am good? - Matthew 20:15

To God be the glory, not man, never man.

[Alamo-Girl]

I look forward to reading Hawkins' speculations as they develop. In the end, I expect the best theory to come from the geometric physicists' corner.

After all, physicists tend to look at dark matter (the most likely suspect) through the lens of their own discipline.

No doubt Hawkins will look at black holes up front.

Geometric physicists (Vafa, Randall, etc.) will consider dimensionality (e.g. the theory that gravity is inter-dimensional and dark matter is a region of negative gravity in 4D) up-front.

Particle physicists on the other hand would likely approach the issue with the presumption of four dimensions, e.g. subatomic particles.

[Kevmo]

Thanks for the post, Alamo Girl. Would you say it is a proper extension of Occham’s Razor to submit that having 4 dimensions is more likely than having 110 dimensions?

[shibumi]

Traditional Cosmology keeps insisting that the speed of light is constant.

This assumption is made by observing local effects at distances that are absurdly small *if* the measurements of the universe they yeild are accurate.

There is no way to prove conclusively that light speed is an absolute, or that the “laws” we formulate by observing light in our local area of the universe hold true in a universe spanning mega and giga parsecs.

(All that can be in the Mind of God, IS.)

((.....and His Mind is timeless.))

[Alamo-Girl]

You're quit welcome, dear Kevmo!

Concerning your question, the answer would depend on the observer.

An observer with 2 dimensional perception cannot intuit 3+ dimensions. Given some indirect evidence and the tools of math and logic, he might conclude a third dimension is likely. But if there is no indirect evidence of that dimension, to him it is unlikely. However if he is an observer with 3 dimensional perception ... and so on.

In the end, the total number and types of dimensions (temporal, spatial, etc.) is both unknown and unknowable. The error would be to say that other dimensions do not exist because an observer cannot perceive them directly or indirectly.

BTW, I often use that as an example why God's promise to Israel will never be broken (emphasis mine.)

But this [shall be] the covenant that I will make with the house of Israel; After those days, saith the LORD, I will put my law in their inward parts, and write it in their hearts; and will be their God, and they shall be my people.

And they shall teach no more every man his neighbour, and every man his brother, saying, Know the LORD: for they shall all know me, from the least of them unto the greatest of them, saith the LORD: for I will forgive their iniquity, and I will remember their sin no more.

Thus saith the LORD, which giveth the sun for a light by day, [and] the ordinances of the moon and of the stars for a light by night, which divideth the sea when the waves thereof roar; The LORD of hosts [is] his name: If those ordinances depart from before me, saith the LORD, [then] the seed of Israel also shall cease from being a nation before me for ever.

Thus saith the LORD; If heaven above can be measured, and the foundations of the earth searched out beneath, I will also cast off all the seed of Israel for all that they have done, saith the LORD. - Jer 31:33-37

God's Name is I AM.

[valkyry1]

I understand that and I’m totally with you on those observations.

[Quix]

INDEED.

The Earth is The Lord’s . . .

[Quix]

Well put, imho.

Much agree.

[Quix]

ABSOLUTELY INDEED:

BTW, I often use that as an example why God’s promise to Israel will never be broken (emphasis mine.)

But this [shall be] the covenant that I will make with the house of Israel; After those days, saith the LORD, I will put my law in their inward parts, and write it in their hearts; and will be their God, and they shall be my people.
And they shall teach no more every man his neighbour, and every man his brother, saying, Know the LORD: for they shall all know me, from the least of them unto the greatest of them, saith the LORD: for I will forgive their iniquity, and I will remember their sin no more.

Thus saith the LORD, which giveth the sun for a light by day, [and] the ordinances of the moon and of the stars for a light by night, which divideth the sea when the waves thereof roar; The LORD of hosts [is] his name: If those ordinances depart from before me, saith the LORD, [then] the seed of Israel also shall cease from being a nation before me for ever.

Thus saith the LORD; If heaven above can be measured, and the foundations of the earth searched out beneath, I will also cast off all the seed of Israel for all that they have done, saith the LORD. - Jer 31:33-37

[LeGrande]

Looks like you were right! The gravitational effects win out over the opposing effects due to the high speed of the satellite.

Actually I was using that example to show when I was wrong : ) I learned it the hard way when I was helping design the guidance system for the Tomahawk.

[ETL]

I learned it the hard way when I was helping design the guidance system for the Tomahawk.

Wow! Very impressive. Thanks for your service on the program.

[ETL]

Of course the gravitational slowing down of the earthbound observer’s clock would depend on where he/she was on the Earth’s surface. Some locations have a higher level of gravity than others. It depends on the density of the rock below. Also, near the equator, there is an outward force (acting in the opposite direction from gravity) due to the spinning of the Earth (about 900 miles/hour at the equator).

[LeGrande]

Of course the gravitational slowing down of the earthbound observer’s clock would depend on where he/she was on the Earth’s surface. Some locations have a higher level of gravity than others. It depends on the density of the rock below. Also, near the equator, there is an outward force (acting in the opposite direction from gravity) due to the spinning of the Earth (about 900 miles/hour at the equator).

Hmm, again I don't know for sure : ) First off the spinning of the earth doesn't affect the warping of spacetime (gravity) so the equator example seems to be wrong.

The more interesting question to me would be what would be the clock speed for a clock in the center of the earth where it would 'feel' no gravity. It is at the bottom of a gravity well so I would expect that it would be very slow, but it might be that the balancing of gravitational forces at that point produces a 'peak' in the gravitational field, counteracting the other warping?

Always keep in mind that every observer will see his clock running faster than other clocks which are moving with respect to him.

[ETL]

First off the spinning of the earth doesn't affect the warping of spacetime (gravity) so the equator example seems to be wrong.

You're right! It would only affect a person's weight (making them lighter). Not sure what I was thinking there.

[ETL]

Also see: Sagnac distortion

“GPS observation processing must also compensate for the Sagnac effect. The GPS time scale is defined in an inertial system but observations are processed in an Earth-centered, Earth-fixed (co-rotating) system, a system in which simultaneity is not uniquely defined. A Lorentz transformation is thus applied to convert from the inertial system to the ECEF system. The resulting signal run time correction has opposite algebraic signs for satellites in the Eastern and Western celestial hemispheres. Ignoring this effect will produce an east-west error on the order of hundreds of nanoseconds, or tens of meters in position.[72]”

http://en.wikipedia.org/wiki/Global_Positioning_System#Relativity

Note: this in addition to the two other relativistic effects in my earlier Wiki post (#80):
http://www.freerepublic.com/focus/chat/2491839/posts?page=80#80

[LeGrande]

Yep, the fact that simultaneity is relative leads to all kinds of unexpected consequences.

I think all of this is fun :)

[ETL]

A great illustration of the relative nature of simultaneity has a train moving past an assumed stationary observer on a platform alongside the train. At the center of the train car is a 2-way light beam emitter. To the person on the train the two light beams reach opposite ends of the car at precisely the same time. But to the observer on the platform watching the train go past left to right, the beam in the direction of the train's motion takes longer and longer to reach the front end of the train (because he sees it moving ahead of the advancing beam). While the beam directed in the opposite direct only approaches the halfway point between emitter and the rear end of the car. And once again, one effects progressively wins out over the other.

http://en.wikipedia.org/wiki/Relativity_of_simultaneity

[SunkenCiv]

Thanks Swordmaker! Halton Arp ping. :')

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[SunkenCiv]

Thanks Swordmaker.

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