"It's similar to the waves we see on the ocean," said Unruh. "They are not affected by the intense dance of the individual atoms that make up the water on which those waves ride."
But if space and time are fluctuating, why can't we feel it?Obviously, because we are fluctuating with it, all things being relative. It's not like we are standing outside of space/time, just because we can talk about it.
...what if everything, and everything that everything is made of, is shrinking all the time - atomic diameters getting smaller and smaller with time.
...what if everything, and everything that everything is made of, is shrinking all the time - atomic diameters getting smaller and smaller with time.
it predicts that there would be an incredibly large density of vacuum energy, far more than the total energy of all the particles in the universe. If this is true, Einstein's theory of general relativity suggests that the energy would have a strong gravitational effect and most physicists think this would cause the universe to explode
So their calculations show that spacetime vibrates between expansion and contraction, with a bias toward expansion. How is the expansion accelerating? Does the fluctuation progress toward a greater bias toward expansion, or is there a constant rate of bias that accumulates? Like most Phys.org articles, very little detail....Every time spacetime expands it admits more dark energy causing even more oscillations (actually uncertainty). Called exponential expansion.
It may also be that the Expansion that we are able to see is actually only a 'local' effect, that other parts of the universe may be contracting, such as near high mass objects.I don't see any local expansion, only between galaxies. High mass objects are being collected by gravity, as in black holes, but contracted, I don't know. Maybe only forming a denser object.
Is there an implication here that these tiny fluctuations give rise to particles ?
I wonder if this is like a 'super-duper-string theory', since vibrating strings expand and contract, except it would be at a more fundamental level. That is, are SS composed of strings themselves?
@xinhangshen You might be in for a rough here but i'll let others argue the point. This should be fun. Just to start things off, I understood that GR plays a greater role than SR in GPS etc. especially when considering that satellite experience differing gravitational values during their path...maybe you are just advertising your paper? You might also clarify where your quote is relevant to the present article, which my, as yet brief, perusal of the main paper doesn't mention SR.
@Whydening Gyre Oh yeah I always like a 'spin' on things so that I can see who 's trying to 'hang on' there, Ha! But at 10^-120 would there be too much space or not enough?
An interesting part of this is that this math may represent a point of attack for linking gravity physics to macroscopic phenomena, if anyone can get their head around it. These oscillating patches of spacetime foam may actually be the strings of string physics, or the loops of LQG.I'm thinking these oscillations trap dark energy leading to gravity and the exponential growth of spacetime. On the micro level these oscillations may be trapped and synchronized to mediate forces such as the strong force.
Actually, on my paper mentioned above, I have proved that if clocks are synchronized in one inertial reference frame, then they are synchronized in all inertial reference frames because clock time is absolute and universal.
Some people may argue that the clocks are only synchronized in the earth centered inertial reference frame, and are not synchronized in the reference frames of the GPS satellites. If it were true, then the time difference between a clock on a GPS satellite and a clock on the ground observed in the satellite reference frame would grow while the same clocks observed on the earth centered reference frame were keeping synchronized. If you corrected the clock on the satellite when the difference became significant, the correction would break the synchronization of the clocks observed in the earth centered frame. That is, there is no way to make a correction without breaking the synchronization of the clocks observed in the earth centered frame. Therefore, it is wrong to think that the clocks are not synchronized in the satellite frame.
Actually, on my paper mentioned above, I have proved that if clocks are synchronized in one inertial reference frame, then they are synchronized in all inertial reference frames because clock time is absolute and universal.
Actually, on my paper mentioned above, I have proved that if clocks are synchronized in one inertial reference frame, then they are synchronized in all inertial reference frames because clock time is absolute and universal.
And yet we have already done experiments with actual clocks that show it's not as you say.
Reality trumps thousands and thousands of pages of theory any day.
" ...there are many factors can influence the accuracy of the atomic clocks."Wow, who idiotically claimed that? The entire point of atomic clocks is to be an absolutely locally accurate time reference; our actual reference of time, the SI definition of the second, is based on them. Specifically, the "second" is defined as exactly 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium 133 atom.
...the "second" is defined as exactly 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium 133 atom.So what happens at 1g?
...the "second" is defined as exactly 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium 133 atom.So what happens at 1g?
So now my sea level laboratory cesium standard located on the equator is rotating around the earth's axis once every 24 hours along with most everyone else. Anything happen here?Where are you looking from? This is a very important question if you are dealing with any kind of relativity.
Gravitation and flat space don't get along too well.The solution to this little quandary is to define the transition frequency in flat space. But my laboratory is not in flat space. So what would be the actual transition frequency that I observe in my lab?
That's why stars observed close to the Sun during an eclipse appear to be in different positions than when they're far from it.So the laws of physics apply to any observer in the right position. If you're not in the right position to make the observation this doesn't mean the laws of physics are observer dependent.
@Seeker unless your lab is close enough to a neutron star or black hole to be spaghettified by the gravity and roasted post-well-done by the radiation, you don't need to account for GRT in your lab.Interesting. No need to account for gravity with orbiting clocks. At least cesium standards. They should be glad to hear that.
That's why stars observed close to the Sun during an eclipse appear to be in different positions than when they're far from it.So the laws of physics apply to any observer in the right position. If you're not in the right position to make the observation this doesn't mean the laws of physics are observer dependent.
No need to account for gravity with orbiting clocks.Not if you're local to the clock. If you're not, then lots of need.
I don't understand why you think relativity isn't part of the Laws of Physics.If it is then best use it.
Not if you're local to the clock. If you're not, then lots of need.Well I'm not so let's use it.
The understanding of things is based on finding common aspectsNo, it's not. The understanding of things is based on the ability to accurately describe their behavior, and you cannot.
@Seeker, you're in space so close to flat that very weak gravity doesn't have any effect, locally. It's orders of magnitude below our ability to measure locally.
I been tryin' to tell you that for about five posts now.
If so, why we aren't using epicycle models anymore?Because they couldn't accurately describe the movements of the planets. Partial explanation is insufficient; complete explanation is mandatory.
@Seeker, you're in space so close to flat that very weak gravity doesn't have any effect, locally. It's orders of magnitude below our ability to measure locally.
I been tryin' to tell you that for about five posts now.
So why do they define it for flat space? Why correct clocks for gravity anyway? Who needs general relativity?
Well, you cannot explain, why the gravity follows the inverse square law and how the magnets are workingHow do you know? Have you asked me?
@Mimath, I'l waste a little more time on this.
First I was absolutely not kidding.....
Second, Hafele-Keating has been repeated many times by satellites...
And I was unfortunately not kidding at all about the non-peer-reviewed status of the Proceedings of the SPIE. Hopefully they do better in their technical journals of record.
I already addressed itNo, you didn't. You claimed I couldn't explain it and I did. You haven't refuted it, and that's that.
Why the gravity follows inverse square law like the intensity of light and not like the force from magnet?@Dingbat, why are you falsely claiming the force from a magnetic pole doesn't follow the inverse square law? Do you have some experiment that proves this?
I already linked itBullsxxt. Direct lie. Link it again and prove me wrong. Or tacitly admit you lied.
@Mimath, after watching @Dingbat claim I couldn't explain the inverse square law and watching me explain it, I'm surprised you're even asking about anything this idiot claims. I really do suggest you not bother with people who make claims, get them disproven, and then try to change the subject. It's really pretty probitive.
@Seeker, you're in space so close to flat that very weak gravity doesn't have any effect, locally. It's orders of magnitude below our ability to measure locally.
Because details matter. And if you ignore GRT your GPS gives a position that's way off.They sure do. I haven't detected any problem in measuring gravity locally.
I have no idea what you're talking about with Earth's gravity. Gravity on Jupiter (which is undeniably in space) is stronger than Earth's, so what you said doesn't seem to make much sense.I'm not talking about Jupiter's gravity. I'm talking about earth's gravity. 1g is the strongest gravity exerted by earth than anywhere else in the U including Jupiter. Earth's gravity is even smaller at the supermassive black hole at the center of our galaxy.
@Seeker, it's not at all clear to me what you're asking.You told us the cesium transition frequency for flat spacetime. I'm asking what is it at 1g.
LOL... Check the sentence "But we observed the monopoles" at this page.
"Check (and click on) @Dingbone's in-line links" Ok. Now I see the link. Oddly there is no visual indication to infer it has a hyperlink to it which usually is differentiated by color, underline etc. And that's a site issue. Or maybe it does not show correctly on Safari.
@DS@Seeker, it's not at all clear to me what you're asking.You told us the cesium transition frequency for flat spacetime. I'm asking what is it at 1g.
I strongly recommend you do not demonstrate your ignorance further but instead remain quiet and see if you can learn some real physicsYou do know dingbat is zephyr don't you? And you're really trying to reason with him?
@DSI don't know what "Earth's gravity" means.I have no idea what you're talking about with Earth's gravity. Gravity on Jupiter (which is undeniably in space) is stronger than Earth's, so what you said doesn't seem to make much sense.I'm not talking about Jupiter's gravity. I'm talking about earth's gravity. 1g is the strongest gravity exerted by earth than anywhere else in the U including Jupiter. Earth's gravity is even smaller at the supermassive black hole at the center of our galaxy.
@DSThe same. Measurement of the frequency is done locally by the atomic clock, so gravity is not strong enough to alter it measurably. The real question is where you are when you're watching it. If you are also local to it (it's "in your lab") then that's what you'll see too. If it's on the ground and you're in orbit observing it, then you'll see something different, and vice versa. GRT gives the equations for what you can expect to see if you're not observing it locally, and for what its value will be if someone takes it "out of your lab" and flies around the world with it, or boosts it to orbit and then brings it back, compared to an identical clock that was synchronized with it that remains "in your lab."@Seeker, it's not at all clear to me what you're asking.You told us the cesium transition frequency for flat spacetime. I'm asking what is it at 1g.
It means the local value of gravity is zero. This happens far outside galaxy clusters, and at particular points within the Solar System at particular times depending on the exact positions of the planets.@DS@Seeker, it's not at all clear to me what you're asking.You told us the cesium transition frequency for flat spacetime. I'm asking what is it at 1g.
Never did get the "flat space/time" thing...
It's always curving somewhere...
As to your question - 1g is a measurement parameter of (local) space/time. (which also happens to correspond with curvature of space/time - go figure)Or is in such a locality now. You have it precisely, @Whyde.
The cesium transition frequency should always read the same in whatever locality it is a part of - TO the local observer. The difference appears when it it has spent any time in - a different locality.
The cesium transition frequency should always read the same in whatever locality it is a part of - TO the local observer. The difference appears when it it has spent any time in - a different locality.Moving the clock to a different location is pointless. Use similar clocks in say Denver and DC. Track their cumulative time. Track them long enough and you will find they start to diverge. Think there is a problem with the clocks? Could be. So switch them and repeat the measurements. Same effect? Then there's nothing wrong with the clocks.
Let's try this another way: you yourself are under the influence of the gravity field wherever you are. You will always perceive a clock that is under the influence of the same value of the gravity field as you are to keep time to one second per second, or have 9,192,631,770 cycles during what you define as 1 second if it is a cesium atomic clock. You will also perceive some clock in a different gravity field as having some different number of cycles, depending on the difference between your field and the field where that clock is. A clock under the influence of the same gravity field value you are is equivalent to a local clock, as long as it's not moving relative to you.You don't define the second from the cycles on your clock unless you're in free fall. Of course you could know the expected difference from your locality and free fall and define the second from your local observation if you do the correction properly.
@Seeker, are Denver and DC both "in the lab?" Given Denver is a mile high, I think not. But I bet our equipment isn't good enough to show the difference.Yes there is a lab in Denver and I suppose one in DC. Run those clocks long enough and I assure you you will find they diverge. Else pitch GR. But you say there must be something wrong with the clocks? No problem. Switch the clocks and repeat the measurement.
You don't define the second from the cycles on your clock unless you're in free fall.No, that's incorrect. If your clock is local then you always define seconds from your clock.
Yes there is a lab in Denver and I suppose one in DC.No, that's not what I said. I said "are they the same lab as you define it." And you just answered, "No." So that's fine, the DC lab is local to DC and the Denver lab is local to Denver.
I assure you you will find they diverge.Eventually, yes, they must. They are not local to one another.
And I still think this is a peek at the math that will be required for any quantum theory of gravity.Does the expansion of spacetime require a quantum theory? If not then forget about any quantum theory of gravity.
No, that's incorrect. If your clock is local then you always define seconds from your clock.Define night as day if you want. But it won't do you that much good because that's not how it's done.
that's not how it's doneI can't imagine how you think it's done if it's not from local atomic clocks. How about you explain that to me.
I can't imagine how you think it's done if it's not from local atomic clocks. How about you explain that to me.I did once but I guess you weren't paying attention. You have to know enough about GR to apply the right correction for altitude to your local time.
You have to know enough about GR to apply the right correction for altitude to your local time.So? Explain it. Then you'll know how it works for orbits.
I don't understand what you're asking, @Seeker. The expansion of spacetime is an observation; it doesn't require any theory at all. It's a fact.So I think you answered that question. Ergo gravity doesn't require any quantum theory. It just happens as a result of expansion. I know it's counter-intuitive, but that's just the way things work sometimes.
It just happens as a result of expansion.You mean gravity? No, that's incorrect. Gravity would happen as a result of mass whether expansion was occurring or not.
So? Explain it. Then you'll know how it works for orbits.I think clocks in orbit are in free fall.
I think clocks in orbit are in free fall.That's only approximately true, and doesn't matter to the curvature of the space they're in.
You mean gravity? No, that's incorrect. Gravity would happen as a result of mass whether expansion was occurring or not.I told you it was counter-intuitive. Gravity happens as a result of quantized mass which doesn't expand while everything else around it is.
That's only approximately true, and doesn't matter to the curvature of the space they're in.Changes in g-values are compensated by changes in the orbit. Approximate truth is above my pay grade.
@Seeker, just because you're in free fall doesn't mean you're in flat space.Good point. Where would you fall?
As for timekeeping, no, I need accuracy. Astronomy requires good timekeeping so you can see things like Jupiter's moons disappearing behind it and reappearing on the other side, and so you can point the telescope.Sounds like about one second accuracy should do.
Where would you fall?
Along a geodesic. Which can be towards a massive body like Earth -There is no flat spacetime in earth's gravitational field. Add a second body, such as the moon, and there is no gravity at the Lagrange points. But normally you wouldn't describe a point as flat.
Where would you fall? .
In flat spacetime (as in curved spacetime) the geodesic is a straight line.So in flat spacetime you would fall on a straight line. I can believe that provided you got a little nudge to start the fall.
@Seeker, curved spacetime doesn't work like curved space would.Neither one works. Maybe warped but not curved. Especially like around a black hole.
spacetime is stretched.. That is, gravity pulls down on the rope. Or stretches the rope downward.
@Seeker, orbits are curved. It's kind of obvious. I don't see much room for confusion.Good thing too. Just don't try selling me that snake oil about objects in orbit traveling in straight lines in curved spacetime, thank you.
Just sayin'.
@Seeker, orbits are curved. It's kind of obvious. I don't see much room for confusion.Good thing too. Just don't try selling me that snake oil about objects in orbit traveling in straight lines in curved spacetime, thank you.
Just sayin'.
Curvature of space/time is irrelevant (other than that it trickle-down determines subordinate curvatures....) If it ISN'T curved, why would anything inside of it curve?Because of gravity.
@WGCurvature of space/time is irrelevant (other than that it trickle-down determines subordinate curvatures....) If it ISN'T curved, why would anything inside of it curve?Because of gravity.
@xinhangshen
I have no idea what your on about...
"Einstein's general relativity theory says that gravity curves space and time, resulting in a tendency for the orbiting clocks to tick slightly faster, by about 45 microseconds per day. The net result is that time on a GPS satellite clock advances faster than a clock on the ground by about 38 microseconds per day."
http://physicscen...will.cfm
For this reason the satellites clocks are designed to run "slow", because of empirical observation.
Ground control stations also monitor and update a satellites time as well as other navigational data, at least once a day.
@WGCurvature of space/time is irrelevant (other than that it trickle-down determines subordinate curvatures....) If it ISN'T curved, why would anything inside of it curve?Because of gravity.
So.... You're saying gravity determines space/time characteristics?
NO WAY!
...Space/Time creates curvature. Which it can only do by being - curved.Bowl sheet. It creates curvature by pulling down. Like my rope example. It's not rocket science. Really.
...Space/Time creates curvature. Which it can only do by being - curved.Bowl sheet. It creates curvature by pulling down. Like my rope example. It's not rocket science. Really.
You are saying a vector direction, then...A total force vector having both direction and magnitude.
You are saying a vector direction, then...A total force vector having both direction and magnitude.
...gravity is generating that force, right?I don't think so.
A property of mass...Like people are a property of the weather.
Question... is everything within our visible U in motion? Straight or curved? (or cork-screwing...)We wouldn't know if it was because everything is uncertain as far as position and time is concerned.
To me, the cork-screwing appears to be a result of gravity affecting massive bodies from a number of different vectors...Cound be a way of conserving energy and momentum.
...gravity is generating that force, right?I don't think so.
A property of mass...Like people are a property of the weather.
Question... is everything within our visible U in motion? Straight or curved? (or cork-screwing...)We wouldn't know if it was because everything is uncertain as far as position and time is concerned.
To me, the cork-screwing appears to be a result of gravity affecting massive bodies from a number of different vectors...Could be a way of conserving energy and momentum.
...gravity is generating that force, right?I don't think so.
Kinetic, then?The gravitational force is generated by gradients in the dark energy.
A property of mass...Like people are a property of the weather.
In a roundbout way - there are..:-)Ok. let's call it complicit. Quantized matter is complicit in about 25% of gravity. The rest is dark matter.
Question... is everything within our visible U in motion? Straight or curved? (or cork-screwing...)We wouldn't know if it was because everything is uncertain as far as position and time is concerned.
I disagree. We know where we ARE. And what our motion(s) are.Maybe but the question was everything not we.
To me, the cork-screwing appears to be a result of gravity affecting massive bodies from a number of different vectors...Could be a way of conserving energy and momentum.
The U does like to take the path of least resistance...:-)Sounds right on.
The U does like to take the path of least resistance...:-)
Sounds right on.Something called the principle of least action comes to mind. It's been a while though.
HannesAlfven
May 15, 2017There is a sense about this that they are GUESSING.