What Exactly Is Spacetime? Find Out Inside

originally posted by: Mary Rose
Particle in cell?

originally posted by: Nochzwei
Pilot in command

Is "PIC" so common that everyone knows what it means?

originally posted by: AnarchoCapitalist
a reply to: Soylent Green Is People

The video is an absurdity.

Space has no properties that can act upon matter, so using a bending sheet as an analogy is simply spreading a religious belief.

NoRulesAllowed correctly identified how the orbital process works. The lack of friction in space allows an object to perpetually fall around the Earth.

But isn't gravity the force causing the satellite to fall around the Earth? (i.e., gravity causes the satellite's orbit).

The "gravity well" in the video simply symbolizes that gravity that is defining the orbit.

a reply to: Soylent Green Is People

Gravity pulls due to the electromagnetic properties of matter, it doesn't create a gravity well.

A gravity well is a fictitious concept of bending space.

Gravity is not a fictitious force, it is a real force, and it arises from real properties of matter - not space.

a reply to: AnarchoCapitalist

It's always nice to read these kind of threads . Thanks.

Time is simply a product our brain creates once it gains self consciousness and is able to recognize the physical world around it. Most people don’t remember a thing of their first seven years after their birth , that is because the brain is just capable of observing space in a limited way at this point , and is not aware of time at all yet. Thus the first seven years or so is basically reserved for building the concept of spacetime. Thus we can perhaps say that until that happens , the first seven years in a human beings life is basically time that goes to waste (seen from a personally point of view) . Thus this period is time that we cannot actually add to our normal life span as the brain stores no memory of it. It is simply not capable of storing any memories of anything at that point, because time is not fully developed yet.

Time does therefore not exist as a physical phenomenon in the universe. Thus it is neither particles or beams but just a product of our brains functionality , which we all need to navigate and make our way around in the physical world. Animals is not aware of time or have self awareness like we do. Neither are they aware of the universe around them. Their brains only allow them to observe the physical surrounding close to them, and they have only limited awareness of time. This is because their brains are not designed for other purposes.

In ancient texts we can read that after the ‘Gods’ had terra formed the Earth and created the multitude of different life forms on it, they all agreed that it was perfect and amazing. However (they taught). What’s the purpose of it all if there is no one around that is able to observe and understand and interact with it all. Thus they created a being that was able of being self aware and thus being aware of time and space.

Anyway. That’s my simple theory of time. It’s a product of our smart brain.

a reply to: AnarchoCapitalist

That's fine. I personally disagree with your idea of the "Electric Universe" and your ideas of how gravity works, but whatever.

As I said in my post, the video was meant to "symbolize" gravity; it isn't meant to be a literal representation of how gravity works.


I just thought that when you wrote in your post the following...:

originally posted by: AnarchoCapitalist
NoRulesAllowed correctly identified how the orbital process works. The lack of friction in space allows an object to perpetually fall around the Earth.

...I thought that you were disagreeing with me when I said that gravity is what makes satellites fall around the earth, and disagreeing with me when I said that this falling due to gravity (PLUS an applied momentum in a direction generally perpendicular to gravity) is what defines the satellite's orbit.

The main point of my post was the Newton's Cannon graphic and information. The Newton's Cannon thought experiment shows how orbits work -- and shows how an orbit of a satellite is defined by how the Earths Gravity pulls that satellite back to earth -- i.e., a satellite orbits because it falls to Earth while at the same time moving "sideways" or parallel to the earth's surface...

...i.e., satellites orbit the earth because earth's gravity is pulling them down while they are moving generally perpendicular to that pull.

That is true no matter which theory of gravity you subscribe to.

a reply to: AnarchoCapitalist

If spacetime cannot be bent, how come light always reach us at the same speed?

Gravity has a squared falloff much like radiated energy. In my opinion, if you were to convert mass to it's energy equivalent, and create a point cloud mapping that energy density associated with where the object occupies space, you're going to see a gradient that correlates with that object's gravitational field. If you consider the permittivity and permeability of a vacuum and that energy's effect on it, I have a feeling that would go a good ways to explaining the gravitation phenomena. (The energy pushes out, but the resistance to that energy by space pushes back in.)

originally posted by: AnarchoCapitalist
Peratt showed how this was possible using PIC simulations and lab observations, and before that, Alfven predicted double radio sources before they were even discovered based on his experience with plasma pinches.

I’ve tried two times to get an answer to my question.

I’m going to try one more time.

What is “PIC”?

a reply to: Mary Rose

I didn't answer because you answered your own question already.

Particle in cell

OP, I'm glad you clarified that concept in such an intelligent manner.
It doesn't happen very often to stumble upon a thread that makes me think "thanks god for people with common sense!" S&F for that!

a reply to: AnarchoCapitalist

The video is an absurdity. Space has no properties that can act upon matter, so using a bending sheet as an analogy is simply spreading a religious belief. NoRulesAllowed correctly identified how the orbital process works. The lack of friction in space allows an object to perpetually fall around the Earth.

Exactly !!
They explain gravity using gravity

They have a problem with Black Holes. This can not be driven by any force in any light speed constant Universe.
Escape velocity equal C means C escapes and faster is not allowed, ( gravity as opposed force ) therefore such thing requires some property of space, which as a scalar value like space curvature is speed independent and mathematically holds the light inside the event horizon.

originally posted by: AnarchoCapitalist
a reply to: Soylent Green Is People

Gravity pulls due to the electromagnetic properties of matter, it doesn't create a gravity well.

A gravity well is a fictitious concept of bending space.

Gravity is not a fictitious force, it is a real force, and it arises from real properties of matter - not space.

Other than experimental facts like:

a) protons are much more massive than electrons, and yet they have the same magnitude and opposite signed charges. Clearly something other than charge & electromagnetism relates to gravitation.

b) gravitational lensing is a quantitatively verified experimental phenomenon, as is gravitational redshift, as well as geodetic and frame-dragging directly verified by experiment.

People who are into 'alternative physics' are frequently ignorant of the depth of quantitative experimental evidence supporting the standard models.

a reply to: mbkennel

Nobody denies your theory is describing the observed mathematically correct.
I'm sure they work well till some new data from observation opposes the theory,
than some new Angels have to be made up to fit the equations... and those hold again

'alternative physics'

You are right on this, if search for what you mean by this and type 'alternative physics wikipedia' in Google those are the first four I get
Multiverse
Many-worlds interpretation
Theoretical physics
Interpretations of quantum mechanics

some bold words theories...

originally posted by: mbkennel
Other than experimental facts like:

a) protons are much more massive than electrons, and yet they have the same magnitude and opposite signed charges. Clearly something other than charge & electromagnetism relates to gravitation.

b) gravitational lensing is a quantitatively verified experimental phenomenon, as is gravitational redshift, as well as geodetic and frame-dragging directly verified by experiment.

People who are into 'alternative physics' are frequently ignorant of the depth of quantitative experimental evidence supporting the standard models.

a) To me all that means is gravity is an electromagnetic effect that is unrelated.

b) No lab has ever produced gravitational lensing. It is a theory, not a fact. There are alternative explanations, such as plasma self-focusing, that are ignored.

Oh, and frame dragging has never been proven either. It's supported by the flimsiest of data. Gravity Probe B was a failure. The final report issued by the Gravity Probe B team highlights problems created by the effects of “contact potential difference” induced error on the gyros. The raw data showed no signs of any frame dragging at all.

A comment on the findings by an astrophysicist:

Of the 4 gyroscopes (centering on the frame-dragging effect) 3 of them (#1,#2, and #3) show errors that admit values compatible with predictions closer to 0 mas/yr than to the -39 mas/yr prediction. One of them (#2) is compatible with a null result. Gyroscope #4 is compatible with -60.6 mas/yr . And these are the numbers achieved after more than 5 years of fitting the raw results to something tolerable.

A 2008 NASA review of the GPB project gave it a failing grade and made the point that:

“the reduction in noise needed to test rigorously for a deviation from general relativity ‘is so large that any effort ultimately detected by this experiment will have to overcome considerable (and in our opinion, well justified) scepticism in the scientific community’.”

The geodetic effect can easily be explained using steady state versions of relativity, such as proposed by Lorentz. Thus, the geodetic effect does not prove space actually bends.

www.newscientist.com...
www.physicsforums.com...

IMO only nutcases believe that space can be bent
a reply to: AnarchoCapitalist

a reply to: Nochzwei
Can you take a step beyond ridiculing those of us who perhaps are not as informed as yourself on the nature of Space itself?

What is it? Why can it not be bent by 'something'?

originally posted by: DenyObfuscation
a reply to: Nochzwei
Can you take a step beyond ridiculing those of us who perhaps are not as informed as yourself on the nature of Space itself?

What is it? Why can it not be bent by 'something'?

Nothing cannot bend.

Space is nothing.

Treating nothing as if it is something is an absurdity.

AC already replied and he is spot on. Space is nothingness
a reply to: DenyObfuscation

a reply to: AnarchoCapitalist

Space is nothing.

Source? That's not a joke BTW. I really would like to know more about what 'Space' actually is and is not. Any help from any member would be appreciated.

Treating nothing as if it is something is an absurdity.

I'd agree with that, however it would be equally or even more so to treat something as if it is nothing, if it actually is 'something'.

originally posted by: DenyObfuscation
a reply to: AnarchoCapitalist

Space is nothing.

Source? That's not a joke BTW. I really would like to know more about what 'Space' actually is and is not. Any help from any member would be appreciated.

Treating nothing as if it is something is an absurdity.

I'd agree with that, however it would be equally or even more so to treat something as if it is nothing, if it actually is 'something'.

I linked the wiki articles in the OP.

If you need more information, look at the references in the wiki articles.