Does gravity exist without matter?

Page 3 - For the science geek in everyone, Live Science breaks down the stories behind the most interesting news and photos on the Internet.
Nov 18, 2020
47
1
55
Does potential gravity exist or exists only in relation to matter?
The answer would be no. Light and energy can also create gravity if there's enough in a single place. It'd be possible (or rather, not theoretically impossible) to create a black hole using only light/energy if you could concentrate enough of it in a single spot.
 
Mar 4, 2020
229
29
130
No, there is no physicality at all, without matter. That's what space is. The space in and around our universe is polluted with matter excrement. Static. But out at 100 universal diameters, the space is clean and pristine......completely empty. No physicality at all. The non-entity entity. ZERO. It's the only thing that can fill infinity.
 
Nov 18, 2020
47
1
55
Does potential gravity exist or exists only in relation to matter?
The answer would be no. Light and energy can also create gravity, if there's enough in a single place. It'd be possible (or rather, not theoretically impossible) to create a black hole using only light/energy if you could concentrate enough of it in a single spot.
 
Jan 27, 2020
86
34
80
????
physicality-bla-bla-bla
this
is
not
even
relevant!!!!

According to our current understanding all of space is permeated by fields which are due to quantum mechanical effects only tend around a zero energy value. This means that the vacuum is subject to fluctuations in the fields permeating it.

In essence, particles pop into and out of existence more or less randomly as a result of excitations in these fields making a vacuum, and outer space, a boiling sea of quantum fluctuations. These fluctuations are related to the Heisenberg uncertainty principle and they have been experimentally observed and are part and parcel to modern physics. The Casimir effect describes the fluctuations in electromagnetic fields and has been observed in a lab environment.

An interesting article on quantum vacuum fluctuations can be found here:http://www.hep.caltech.edu/~phys199/lectures/lect5_6_cas.pdf
 
Feb 28, 2020
43
18
55
According to our current understanding all of space is permeated by fields which are due to quantum mechanical effects only tend around a zero energy value. This means that the vacuum is subject to fluctuations in the fields permeating it.

In essence, particles pop into and out of existence more or less randomly as a result of excitations in these fields making a vacuum, and outer space, a boiling sea of quantum fluctuations. These fluctuations are related to the Heisenberg uncertainty principle and they have been experimentally observed and are part and parcel to modern physics. The Casimir effect describes the fluctuations in electromagnetic fields and has been observed in a lab environment.

An interesting article on quantum vacuum fluctuations can be found here:http://www.hep.caltech.edu/~phys199/lectures/lect5_6_cas.pdf
I came across this article claiming to have observed particles popping in and out of existence, by hitting and moving LIGO's 40kg mirrors by 10^-20 metres.

I'm humbled and astonished by what they're doing, for example, they are detecting movements 10^10 times smaller than a hydrogen atom! :)

scitechdaily.com

“Spooky Popcorn of the Universe” Revealed: Quantum Fluctuations Can Jiggle Objects on the Human Scale
Study shows LIGO’s 40-kilogram mirrors can move in response to tiny quantum effects, revealing the “spooky popcorn of the universe.” The universe, as seen through the lens of quantum mechanics, is a noisy, crackling space where particles blink constantly in and out of existence, creating a backgr
scitechdaily.com
 
Mar 6, 2020
134
28
130
So, using the space is a sheet which gets distorted by putting matter on it metaphor, gravity is the bend in the sheet, so then with nothing on the sheet you wouldn't have a bend, so in that case no gravity?
Edit: Or is gravity the potential of the sheet to bend, so whether it can or not? In which case no objects on the sheet would mean there's still gravity because the sheet can still bend.
 
Jan 27, 2020
86
34
80
So, using the space is a sheet which gets distorted by putting matter on it metaphor, gravity is the bend in the sheet, so then with nothing on the sheet you wouldn't have a bend, so in that case no gravity?
Edit: Or is gravity the potential of the sheet to bend, so whether it can or not? In which case no objects on the sheet would mean there's still gravity because the sheet can still bend.

Here is an interesting article from NASA concerning Gravity Probe B and the calculations of the geodetic precession and the frame dragging effect for a mass the size of the Earth, then try to imagine those effects for smaller masses:

May 4, 2011: Einstein was right again. There is a space-time vortex around Earth, and its shape precisely matches the predictions of Einstein's theory of gravity.

Researchers confirmed these points at a press conference today at NASA headquarters where they announced the long-awaited results of Gravity Probe B (GP-B).

"The space-time around Earth appears to be distorted just as general relativity predicts," says Stanford University physicist Francis Everitt, principal investigator of the Gravity Probe B mission.

"This is an epic result," adds Clifford Will of Washington University in St. Louis. An expert in Einstein's theories, Will chairs an independent panel of the National Research Council set up by NASA in 1998 to monitor and review the results of Gravity Probe B. "One day," he predicts, "this will be written up in textbooks as one of the classic experiments in the history of physics."

Time and space, according to Einstein's theories of relativity, are woven together, forming a four-dimensional fabric called "space-time." The mass of Earth dimples this fabric, much like a heavy person sitting in the middle of a trampoline. Gravity, says Einstein, is simply the motion of objects following the curvaceous lines of the dimple.

If Earth were stationary, that would be the end of the story. But Earth is not stationary. Our planet spins, and the spin should twist the dimple, slightly, pulling it around into a 4-dimensional swirl. This is what GP-B went to space in 2004 to check.

The idea behind the experiment is simple:
Put a spinning gyroscope into orbit around the Earth, with the spin axis pointed toward some distant star as a fixed reference point. Free from external forces, the gyroscope's axis should continue pointing at the star--forever. But if space is twisted, the direction of the gyroscope's axis should drift over time. By noting this change in direction relative to the star, the twists of space-time could be measured.

In practice, the experiment is tremendously difficult.

The four gyroscopes in GP-B are the most perfect spheres ever made by humans. These ping pong-sized balls of fused quartz and silicon are 1.5 inches across and never vary from a perfect sphere by more than 40 atomic layers. If the gyroscopes weren't so spherical, their spin axes would wobble even without the effects of relativity.

According to calculations, the twisted space-time around Earth should cause the axes of the gyros to drift merely 0.041 arcseconds over a year. An arcsecond is 1/3600th of a degree. To measure this angle reasonably well, GP-B needed a fantastic precision of 0.0005 arcseconds. It's like measuring the thickness of a sheet of paper held edge-on 100 miles away.

"GP-B researchers had to invent whole new technologies to make this possible," notes Will.
They developed a "drag free" satellite that could brush against the outer layers of Earth's atmosphere without disturbing the gyros. They figured out how to keep Earth's magnetic field from penetrating the spacecraft. And they created a device to measure the spin of a gyro--without touching the gyro. More information about these technologies may be found in the Science@NASA story "A Pocket of Near-Perfection."

Pulling off the experiment was an exceptional challenge. But after a year of data-taking and nearly five years of analysis, the GP-B scientists appear to have done it.

"We measured a geodetic precession of 6.600 plus or minus 0.017 arcseconds and a frame dragging effect of 0.039 plus or minus 0.007 arcseconds," says Everitt.

For readers who are not experts in relativity: Geodetic precession is the amount of wobble caused by the static mass of the Earth (the dimple in spacetime) and the frame dragging effect is the amount of wobble caused by the spin of the Earth (the twist in spacetime). Both values are in precise accord with Einstein's predictions.

"In the opinion of the committee that I chair, this effort was truly heroic. We were just blown away," says Will.

The results of Gravity Probe B give physicists renewed confidence that the strange predictions of Einstein's theory are indeed correct, and that these predictions may be applied elsewhere. The type of spacetime vortex that exists around Earth is duplicated and magnified elsewhere in the cosmos--around massive neutron stars, black holes, and active galactic nuclei.

"If you tried to spin a gyroscope in the severely twisted space-time around a black hole," says Will, "it wouldn't just gently precess by a fraction of a degree. It would wobble crazily and possibly even flip over."
In binary black hole systems--that is, where one black hole orbits another black hole--the black holes themselves are spinning and thus behave like gyroscopes. Imagine a system of orbiting, spinning, wobbling, flipping black holes! That's the sort of thing general relativity predicts and which GP-B tells us can really be true.

The scientific legacy of GP-B isn't limited to general relativity. The project also touched the lives of hundreds of young scientists:
"Because it was based at a university many students were able to work on the project," says Everitt. "More than 86 PhD theses at Stanford plus 14 more at other Universities were granted to students working on GP-B. Several hundred undergraduates and 55 high-school students also participated, including astronaut Sally Ride and eventual Nobel Laureate Eric Cornell."

NASA funding for Gravity Probe B began in the fall of 1963. That means Everitt and some colleagues have been planning, promoting, building, operating, and analyzing data from the experiment for more than 47 years—truly, an epic effort.

What's next?

Everitt recalls some advice given to him by his thesis advisor and Nobel Laureate Patrick M.S. Blackett: "If you can't think of what physics to do next, invent some new technology, and it will lead to new physics."
"Well," says Everitt, "we invented 13 new technologies for Gravity Probe B. Who knows where they will take us?"

This epic might just be getting started, after all…

Author: Dr. Tony Phillips | Credit: Science@NASA
See: https://science.nasa.gov/science-news/science-at-nasa/2011/04may_epic/
 
Jan 27, 2020
86
34
80
Why does the continuous solar wind, accelerate away from the sun, clear thru-out our planetary system? That's a lot of acceleration with a long duration. The solar wind repulses from the sun. A very UN-mass thing to do.

"Repulses" from the sun is probably not the best term to use when describing the solar wind.

The solar wind streams off of the Sun in all directions at speeds between 400 km/s (about 1 million miles per hour) and as high as 900 km/s. The source of the solar wind is the Sun's hot corona, the second hottest zone of the sun except for the core, and the corona may be as hot as 1-2,000,000K. The temperature of the corona is so high that the Sun's gravity cannot hold on to it. Although we understand why this happens we do not understand the details about how and where the coronal gases are accelerated to these high velocities. This question is related to the question of coronal heating.

The solar wind is not uniform. Although it is always directed away from the Sun, it changes speed and carries with it magnetic clouds, interactive regions where high speed wind catches up with slow speed wind, and composition variations. The solar wind speed is high (900 km/s) over coronal holes and low (300 km/s) over streamers. These high and low speed streams interact with each other and alternately pass by the Earth as the Sun rotates. These wind speed variations buffet the Earth's magnetic field and can produce storms in the Earth's magnetosphere.

earth's magnetic field is vital.jpg
The Earth's magnetic field's lines of flux are vitally important for our survival.

The Ulysses spacecraft completed two orbits through the solar system during which it passed over the Sun's south and north poles. Its measurements of the solar wind speed, magnetic field strength and direction, and composition have provided us with a new view of the solar wind. Ulysses was retired on June 30, 2009.​
The Advanced Composition Explorer (ACE) satellite was launched in August of 1997 and placed into an orbit about the L1 Lagrangian point between the Earth and the Sun where it may operate for 75 years. The L1 point is one of several points in space where the gravitational attraction of the Sun and Earth are equal and opposite. This particular point is located about 1.5 million km (1 million miles) from the Earth in the direction of the Sun. ACE has a number of instruments that monitor the solar wind and the spacecraft team provides real-time information on solar wind conditions at the spacecraft.

 
Mar 4, 2020
229
29
130
The corona is a density gradient. We used settled sugar water as a density gradient in the 8th grade. And bowed a flashlight beam thru it. OH-MY. Remind you of anything. They call this simple concept, space-time now.

No one knows what accelerates the solar wind. The corona would only accelerate thru the corona. But the solar wind accelerates clear past Neptune. And probably much farther, no one knows. Think about all the stars for all the eons doing this. And no one sees where or even if, this charge ever re-combines. Maybe the cosmic background is a sign of it recombining. Being presently generated.

There might be more solitary charge than bonded charge in the universe now. Solitary charge has no gravity. It's quite an unstated mystery. Like unstated and ignored helical orbits. Charge is not positive and negative, charge is right handed and left handed.

There is another possibly that science has not considered. And that is handedness. This could not only explain gravity, but might also explain the apparent instantaneous speed of entanglement.

A common gravity field is necessary for entanglement. Gravity might be the fulcrum for the alignment.

And gives it the apparent instantaneous nature.

Handedness......the ignored property. Probably unites everything.
 
Dec 16, 2020
15
1
35
A new look at the nature of gravity was presented by a renowned expert in the field of string theory, a professor at the University of Amsterdam, Erik Verlinde. The scientist developed his own theory in 2010 that gravity is an emergent force of nature, not fundamental. In the same way that temperature arises from the movement of microscopic particles, gravity arises from fundamental changes in the bits of information found in the very structure of spacetime.
This was in 2016.
There are several theories trying to explain gravity without the need to introduce the concept of dark matter.
But there is not a single theory that could explain the existence of gravity without the presence of matter at all
 
Jan 27, 2020
86
34
80
Verlinde's theory doesn't "explain the existence of gravity without the presence of matter". However, he indicates that gravity is a force resulting from "information associated with the positions of material bodies" (an assemblage of matter within a defined contiguous boundary in three dimensional space) and the quantum entanglement (Einstein's "spooky action at a distance") of tiny bits of spacetime information. (see paragraph two, below)

Verlinde proposed that gravity was not a fundamental force of nature but rather emerged out of the interactions of information that fills the universe.

In Prof. Dr. Erik P. Verlinde's (University of Amsterdam) view, based on string theory, quantum information theory and the physics of black holes, gravity is an "entropic*" force that comes into existence as a result of "information associated with the positions of material bodies," as he wrote in his 2011 paper. What drives gravity is the quantum entanglement of tiny bits of spacetime information.

He also didn't think there was such a thing as "dark matter" - a useful construct which is supposedly taking up 27% of the known universe (but is yet to be observed). Now (ca. August 2019), in a new interview, Verlinde reveals he is taking steps towards conceptualizing his groundbreaking ideas in a full-fledged theory.

In 2016, Verlinde's ideas were tested by a team from Leiden Observatory, which found that a key prediction of the physicist held up. They studied the lensing effect of gravitational fields that are far away from the centers of more than 33,000 galaxies and found the numbers to be consistent with what the Dutch scientist's theory showed. The only way to get these calculations to match under the prevalent gravitational theory would have been to invoke dark matter - a potential fudge factor more than fact at this point.

A 2017 study from Princeton University found against Verlinde's ideas, however, showing that they are not consistent with the observed data on the rotation velocities of dwarf galaxies.

While some have accused of Verlinde of publishing his thoughts too early, before they are packaged in a theory that explains all of the implications, the scientist thinks such naysayers don't really understand the way theoretical physics works. "You need to elaborate and test a new idea step-by-step," he explains, adding "We must find the correct formulations and techniques.'

Scientists like the theoretician Koenraad Schalm from Leiden University defend Verlinde, saying that "Contrary to the sceptics' opinions, Verlinde's work is definitely taken seriously". In fact, Verlinde, who is the winner of the Spinoza Prize**, has been cited over 700 times by other scientists.

The physicist himself feels his overall thesis that information is the fundamental building mechanism of the universe is becoming more accepted. Perhaps his long-awaited new paper on the subject can bring it to an even stronger position amidst the main physics ideas of our time.

* entropic: The definition of entropic is having a tendency to change from a state of order to a state of disorder. An example of something entropic is a building which is being demolished.

** Spinoza Prize: The Spinoza Prize, offered by the Netherlands Organisation for Scientific Research (NWO), is the highest scientific research award for top scientists in the Netherlands. The laureates are internationally renowned and know how to inspire young researchers. Spinoza prize winners receive 2.5 million euros to spend on the research of their choice.

See Prof. Verlinde's paper: https://arxiv.org/pdf/1001.0785v1.pdf

See: https://www.sott.net/article/418726-Erik-Verlinde-A-radical-theory-of-gravity

I'm still going to vote with Einstein and his view of space-time, for now.

Hartmann352
 
Last edited:

ASK THE COMMUNITY

Latest posts