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Gravity's Engines
We’ve long understood black holes to be the points at which the universe as we know it comes to an end. Often billions of times more massive than the Sun, they...
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The main story " Splitting Time from Space—New Quantum Theory Topples Einstein's Spacetime," describes recent excitement over a quantum theory of gravity proposed by physicist Petr Hořava of the University of California, Berkeley. Testing theories of quantum gravity in the laboratory is not possible, but computer simulations may offer the next best thing—and they seem to be lending support to Hořava gravity.
Jan Ambjørn of the Niels Bohr Institute at the University of Copenhagen and his colleagues have been using computer simulations to model quantum gravity based on spacetimes built from self-organizing "motes" that fall into place naturally.
So far, they have succeeded in creating a stable four-dimensional spacetime, when viewed at large distances. But when they zoomed in to small distances, they found a strange result—their universe seems to drop two dimensions. So where did the missing dimensions go?
Hořava believes that this dimension drop marks the point at which general relativity emerges in his theory of gravity. In his model, the shackles that force time and space to stretch in unison are removed at high energies and short distances. In a paper published in Physical Review Letters in April, he explains that within this regime, space stretches only a third as quickly as time. "The three spatial dimensions effectively mimic just one normal relativistic dimension," he says, making it look as though two dimensions have vanished.
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13 Comments
Add CommentWoah
Reply | Report Abuse | Link to thisWoah
Reply | Report Abuse | Link to thisHis name is HoYava.
Reply | Report Abuse | Link to thisHm. Seems you have a rendering problem with accented characters...
Reply | Report Abuse | Link to thisIn Aether Wave Theory space-time is density gradient, which is forming by condensation of another density gradients like during nested condensation of gas. http://tinyurl.com/lvj9n3
Reply | Report Abuse | Link to thisPHYSICS
Reply | Report Abuse | Link to thisAND THE PERSONIFICATION OF MESUREMENTS
An hour was giving a lecture
to a Number 8 and a mile.
Mile thought Hour spoke nonsence.
Numbher 8 disliked Hour's style.
"What you are cliaming," Mile called out,
is quite wrong and if you persist
I, along with Number 8,
will be forced to make you desist.
Hour was very much annoyed
and snapped in most furious tones,
"No-one asked you for your view,"
and began to throw sharpened stones.
Mile, being very cautious
and Number 8 being the same,
called out to a passing Speed
to help in this dangerous game.
Speed, who was always ready
to show off if the oddes were right
jumped from a mass in motion
and prepared himself for the fight.
Hour knocked flat Number 8
which sight made Speed turn and run.
Mile was left to face the hour
and finish what it had begun.
Then
something happened that has not
been reported before in rhyme:
Mile and Hour got entangled
and became what is called "Spacetime".
This Spacetime stretched like elastic
and carried the galaxies far
and changed the path of photons
(when they passed too close to a star).
It's hard indeed to imagine
a Spacetime committing such acts,
but that is what physics tells us
and of course physics
reports only facts!
c) Salt Cloud
I sure need to know how to spell ' nonsense'!.... As I find on re-reading my comment above... And to watch my typing errors too, inluding in the title!!
Reply | Report Abuse | Link to thisNew topic
Reply | Report Abuse | Link to this'If the ether exists and is absolutely immobile the speed of light traveling through it
on the source of the earth ought to be diffrent when the light is propagated in the
directions of the motion of the earth (that is, flowing with the ether) and when it goes
in the opposite direction (against the ether).
'' The American physicist Albert A michelson and E. W. Morley devised an experiment
to demonstrate this difference. To their surprise, the result proved negative : the speed
of light was the same in both directon - invalidating the hypothese that light traveled in
an ether.''
.
This (particular) experiment does not seem to me to 'prove' (or even indicate) that light does not
travel in (or through) an 'ether'.
If the ether (or by any other name) was thought to be absolutely immobile then
why speak of something (Light, for example) : 'flowing WITH the ether' . In what direction CAN
an IMMOBILE substance, 'flow'?
If the ether flows (and therefore is NOT immobile) then the spin of the Earth spinning in EITHER
direction would cause (in this hypothese) the ether to flow along 'WITH' the direction of the light.
That is, if Earth spun in the opposite direction, so would the ether flow in that opposite direction..
If the ether was immobile, however, it would make no difference which way the Light flowed through it.
So that, if light flows in the direction of the spin of Earth or against that spin - or, if the spin of Earth
changes to an opposite spin.. Such would not affect that which MIGHT exist (an 'ether') .. It is not proven that,
because light travels at the same speed both in the direction of the spin of earth
AND in the opposite direction to that spin.. there is no IMMOBILE ether.
Evidently, I am missing something here, or misunderstanding the meaning of the words used.
Reply | Report Abuse | Link to thisNew Topic (?)
'If the ether exists and is absolutely immobile the speed of light traveling through it
on the source of the earth ought to be diffrent when the light is propagated in the
directions of the motion of the earth (that is, flowing with the ether) and when it goes
in the opposite direction (against the ether).
'' The American physicist Albert A michelson and E. W. Morley devised an experiment
to demonstrate this difference. To their surprise, the result proved negative : the speed
of light was the same in both directon - invalidating the hypothese that light traveled in
an ether.''
.
This (particular) experiment does not seem to me to 'prove' (or even indicate) that light does not
travel in (or through) an 'ether'.
If the ether (or by any other name) was thought to be absolutely immobile then
why speak of something (Light, for example) : 'flowing WITH the ether' . In what direction CAN
an IMMOBILE substance, 'flow'?
If the ether flows (and therefore is NOT immobile) then the spin of the Earth spinning in EITHER
direction would cause (in this hypothese) the ether to flow along 'WITH' the direction of the light.
That is, if Earth spun in the opposite direction, so would the ether flow in that opposite direction..
If the ether was immobile, however, it would make no difference which way the Light flowed through it.
So that, if light flows in the direction of the spin of Earth or against that spin - or, if the spin of Earth
changes to an opposite spin.. Such would not affect that which MIGHT exist (an 'ether') .. It is not proven that,
because light travels at the same speed both in the direction of the spin of earth
AND in the opposite direction to that spin.. there is no IMMOBILE ether.
Evidently, I am missing something here, or misunderstanding the meaning of the words used.
On either... once thought of as (thin) air became something like a conducting field for radio waves in folks minds.
Reply | Report Abuse | Link to thisWell, these notions were dispelled one by one and as mentioned the later concept finally deflated by MM experiment.
So, if you speak of either, then you speak from an old point of view.
As for it being a motionless substance, if it were so, then the Earth's rotational (or orbital) speed would effect light like a doppler shift, (train whistle changing pitch as it goes by) and
that experiment did not find this expected shift, thus the conclusion was that there was no medium required other than empty space.
Light does exhibit a doppler shift when coming from objects moving away from us, but it has nothing to do with the medium it is traveling in.
Yes, empty space is hard to grasp as it can only be measured by time-volume, not weight, nor charge, and certainly can't be seen as moving, as there is nothing to move EXCEPT the frame of reference of the observer/observed phenomena.
Back to HoYava, I am pleased that it seems to confirm that the big bang was proceeded by a big crunch, and our universe is a cyclic thing, expanding, slowing, compressing and then re-expanding.
It also explains why galaxies are the way they are WITHOUT having to resort to inventing dark matter. Funny, but 95% of yesterdays perceived universe just became imaginary again.
All is well.
For us it is clear space is physical dimension and time merely is a mathematical dimension of change in space which originates from a 3D quantum vacuum.
Reply | Report Abuse | Link to thishttp://phys.org/news/2012-04-physicists-abolish-fourth-dimension-space.html
Time is a numerical order of a duration of a given physical phenomena which run in a 3D quantum vacuum. At the Planck scale there is no time, physical phenomena are immediate. By the immediate phenomena as EPR and gravity information and energy transfer are carried directly by the fundamental grains of a 3D quantum vacuum. Motion of light in a 3D quantum vacuum has its time, at the photon scale there is no "relativity" yet; velocity of light is invariant. "Relativity" starts at the scale of the pi meson.
Reply | Report Abuse | Link to thisyours amrit
www.spacelife.si
The time – as well as the space – are some rules that govern over processes in Matter. Since material objects are some informational patterns, the rules are some analogues to grammar rules and are absolute. The space and the time so are independent on what material process goes – movement, some forces’ mediation, creation of particles, etc. - something like as for grammar rules is indifferent – what text is writing. Time defines that in [dynamical] cause-effect process the cause is always before the effect; the space differs fixed information (all above some zero explanation, of course).
Reply | Report Abuse | Link to thisMore – see http://arxiv.org/abs/1110.0003 (paper “Space and Time”); it may be useful
http://arxiv.org/abs/1004.3712 (paper “the Information as Absolute”)
Cheers