Posted on 03/28/2003 5:49:29 PM PST by vannrox
Huntsville - Mar 28, 2003
For the second time in as many months, images gathered by the Hubble Space Telescope (HST) are raising questions about the structures of time and gravity, and the fabric of space.Using two HST images, astronomers from Italy and Germany looked for but did not find evidence supporting a prevailing scientific theory that says time, space and gravity are composed of tiny quantum bits.
Using existing theories, the team led by Dr. Roberto Ragazzoni from the Astrophysical Observatory of Arcetri, Italy, and the Max Planck Institute for Astronomy in Heidelberg, Germany, calculated that infinitesimally small quantum-scale variations in space time would blur images of galaxies seen from vast distances across the universe.
Instead, when they looked at both diffraction patterns from a supernova and the raw image of a second galaxy more than five billion light years from Earth, they saw images much sharper than should be possible if quantum-scale phenomenon operated as previously supposed. Their research is scheduled to be published in the April 10, 2003, edition of Astrophysical Research - Letters.
"The basic idea is that space time should fluctuate," said Ragazzoni. "If you are looking at light from a huge distance, this light passing through space time would be subject to this fluctuation in space time. They should give a distorted image of the far universe, like a blurring.
"But you don't see a universe that is blurred. If you take any Hubble Space Telescope deep field image you see sharp images, which is enough to tell us that the light has not been distorted or perturbed by fluctuations in space time from the source to the observer. This observation is enough to rule out this effect on the quantum scale.
"You can say," said Ragazzoni, "that this measurement constrains the quantum gravity theory to certain parameters."
This report comes a month after physicists at The University of Alabama in Huntsville (UAH) announced their unsuccessful attempt to use an image from an HST interferometer to find evidence of Planck-scale effects. Taken together, the independent research findings might force physicists to reexamine the scientific underpinnings of the quantum theories of gravity, time and space.
To look for the quantum blurring effect the European team used a parameter from optics, the Strehl ratio, to calculate how sharply the telescope should be able to resolve an image of the distant light source and its first Airy ring - a signature of the interference of the rays of light entering a telescope.
If the popular quantum theories were correct, space-time effects should blur light from distant sources beyond the telescope's ability to resolve them.
They didn't.
"Without a theory to describe this, I think it's hard not to agree that it is time to start to consider theories that do not require this Planck scale, at least not like it is now," said Ragazzoni. "From an experimental point of view, there is no establishment. We are proud to have established in as rigorous a manner as possible the parameters of this quantum effect."
The Planck-scale quantum theories of time, space and gravity were derived from attempts to calculate the theoretical limits to electromagnetic energy, according to a UAH physicist, Dr. Richard Lieu.
By inverting Albert Einstein's theory of relativity (E=mc2 becomes m=E/c2), physicists could calculate how much mass should be added to a photon as it gains energy. Using that, they calculated a theoretical limit to how much energy a photon might contain before gaining so much mass it would collapse into a photon-sized black hole.
That theoretical upper limit was then used to set theoretical limits on time. One cycle of a photon carrying that much energy would last 5 x 10-44 seconds, an interval called Planck time. As the shortest potentially-measurable interval of time, theorists speculated that time moves is Planck time-sized quantum bits.
In his theory of general relativity, Einstein theorized that time, space and gravity are different manifestations of the same phenomenon, much as light and thunder are signatures of the electrical discharge in lightning. If time is made up of quantum bits, that would also mean space and gravity should also be composed of quantum units.
Since the expected blurring "signature" of quantum space time isn't seen, however, it might mean that time isn't made of quantum bits, and neither are space or gravity.
I believe you are incorrect. The laws of macrophysics (mechanics) are time-symmetric. Several quantum mechanical operations have recently been proposed as non-time symmetric (such as K-meson decay). At this point, I am reaching the edge of my expertise (the last time I took a physics course... double-majored physics/math for a while... was several years before the experiments quoted), but several experiments at CERN (see this) and elsewhere have suggested that certain weak force interactions violate charge and parity invariances, which means they must have an equal-sized time variance to balance out the CP violations, in order to remain CPT invariant.
Either way, both CPT invariance and time invariance tend to be premises in order to hypothesize further, as opposed to confirmed fundamental laws. But universal time invariance is most certainly not accepted to the point of saying that "the laws of physics are time symmetric" ...
Yes. That is the most basic application of Einstein's theories (among others...Einstein didn't do all the work!).
Imagine a large trampoline. Now put a bowling ball on the trampoline. The surface of the trampoline will curve downward under the bowling ball, and the surface of the trampoline will bend to a lesser extent in the area surronding it. Now put a marble on the trampoline near the bowling ball. The curvature of the surface of the trampoline will cause the marble to accelerate towards the bowling ball. If you couldn't see the trampoline, you might think that the bowling ball was somehow attracting or pulling on the marble (which is how Newton conceived of the motion in his Laws). But, once you can see the trampoline, you will realize that the marble is simply following the curvature of the trampoline. That is Einstein's great realization.
Likewise, if you were to roll the marble past the bowling ball, the path of the marble would be deflected by the indention in the trampoline's surface. You could view this as some force pulling on the marble, if you couldn't see the trampoline. But, upon seeing the trampoline, you would realize that the marble was simply following a straight line... it's the curved surface that caused the path to change!
The motion of the apple is "downhill" in the sense that its path is curved by space-time towards the Earth. We perceive that "path change" as falling. This is basic (well, intermediate) physics.
Then you posted . . .
"Gravity is due to space-time curvature."
(Seems to me you can't have 'em both)
Is it possible that energy is just simply attracted to energy?
Actually, the Heisenberg Uncertainty Principle is best understood as a mathematical limit: you cannot measure the position of a particle and the momentum to a degree where the product of the uncertainty of the particle's position and the uncertainty of the particle's momentum is less than Planck's constant. So if the effect you are looking for is greater than Planck's constant, the equation does not apply. But I'm not sure how this equation relates to the article. Dealing with general non-mathematical restatements of fundamentally mathematical equations always leads to trouble...
As for "energy attracting energy," this is demonstrably not the case. Massless particles (photons, probably neutrinos, etc.) do have energy, but not mass. This is why cosmologists have been fighting over whether neutrinos do have mass, because it would explain part of the composition and gravitational effects we see in galaxies, despite the fact that we don't see the mass to cause them. So energy does attract other energy, but only when both energies are in the state that we call "matter" and have mass (remember that Einstein's famous equation establishes the convertability of matter and energy: E=mc²)...
I have always thought that the physicist 800 years from now, with get quite a kick out reading today's accepted theories. They haven't scratched the surface......
What's your point? That we will learn a great deal more in 800 years than we know now? Of course we will. Nevertheless, the writings of Aristotle, Galileo, and Newton are still in print, and we still read them with appreciation of how brilliant they were in their day. No one today, with our superior knowledge, snickers at their efforts. Most assuredly, no one in their own time snickered at them with the expectation that their work would eventually be superseded. I think the same is true of our scientific work today.
I only stated that scientist in distant future will surely find some of our current accepted theories regarding cosmology humorous. I am confident of this.
This aplies only to Quantum gravity / space / time.
Quantum effects will continue to operate sort of reliably in the electromagnetic spectrum for the time being. Your apliances will continue to function as well, or poorly, as ever.
So9
God is a real programmer.
He writes Machine Code and runs it on the bare metal.
Operating Systems, especially Unix, are Demonic in origin.
SO9
That is only because causality is defined to give a consistent arrow and a consistent rate to the passage of time.
SO9
As the time traveller once said, "I'll get back to you on that!"
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