matter, energy, space, time and gravity

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Are these five different things or are they just variations or properties of the same thing?

Who knows. My understanding is that we can only talk about these things in terms of how we percieve them affecting each other.

Physicists cannot say for sure what matter is, yet they say it is the cause of gravity, bending time and space, and that it can be converted into energy.

So if matter did not exist, then there would be no gravity and no energy in the universe. Then we have to ask if time and space can exist without matter?

Perhaps in a higher level dimension all these things converge into one thing. I think that is what string theory is saying.

moved from Politics, Philosophy and Religion to Computers, Math, Science, and Technology

i'm just going to be a hippy here and go ahead and say "all is one"

There are guys with more physics than me who could give very abstract and mathematically precise definitions of these things in terms of relativity, quantum mechanics, and the standard model, but it doesn't look like they have posted, so I will give you the Newtonian version of the mathematically precise version of these things.

In classical physics, mass, which is related to matter, is considered to be a quality that is inherent in an object and that cannot be expressed using other units. It is important because it is the factor which changes how quickly things accelerate. F = ma, or force equals mass times acceleration. In other words, the more massive something is, the more force it takes to accelerate it.
My understanding of the higgs boson (I don't understand the math behind it) is that it is like a sticky good that permeates the entire universe and if something gets stuck in the goo easily then it has more mass than something which doesn't get stuck easily. In relativity there is of course the famous equation E = mC^2.

Force is defined as F = ma, and energy is defined as the negative curve integral of a force over distance. If the force is constant and in the same direction as the movement then energy is just equal to - F*d, where d is the distance covered. The minus sign isn't important if you're working with simple problems and you understand intuitively what is happening. So if it takes 10 Newtons (newton is a unit of force) to push a block and I push it 5 meters, then I have spent 50 Joules of energy. It is possible to prove conservation of energy by setting up this equation: (mv^2)/2 = V(x) + E and then deriving by time. Doing so will give you the equation ma = V'(x), which proves that force is equal to the spacial derivative of the energy field. v is velocity, V(x) is an equation describing the energy field, V'(x) is the derivative in terms of x, and E is the energy. (1/2)mv^2 is the expression for kinetic energy. Kinetic energy just means energy associated with motion. Example: if a 40kg block is sliding on frictionless ice at 10m/s then the kinetic energy is (1/2)*(40kg)*(10m/s)^2 = 200kgm^2/s^2 = 200J. If the block slides off the ice and onto some grass or something that has friction that slows the block down, let's say with a force of 10N, then the block will slide a distance of 200J/10N = 20 meters.
*SHORT EXPLANATION: Force is a change in energy.*
When you take higher level physics you learn that there are many things in nature that are conserved and energy is just one of the more common and easily proven constants. I view energy as a mathematical device that makes it easier to solve problems.

In classical physics space is something that is taken for granted and is assumed to be uniform and evenly spaced throughout all space. In special relativity space contracts when you move fast, in general relativity space is something bends because of mass, and in quantum mechanics space has inherent energy. I only understand the first of these 3.

In classical physics time is also something that is taken for granted. In special relativity time slows down when you move fast. You can actually prove this using only the Pythagorean theorem : P

The Newtonian version of the gravitational force between two objects is GmM/r^2, where G is a constant, m and M are the masses of two objects, and r^2 is the square of the distance between the objects. Because I have the equation for the force of Gravity I can integrate it to get the equation for the energy, which is -GmM/r. Gravity is an interesting force because you can see when you set GmM/r^2 = ma, the m's cancel so the movement of the particle does not depend on the mass of the object.
In General relativity gravity isn't really a force but is a bending of space-time. My understanding is that if we could see in 4 dimensions then falling objects would actually be moving in a straight line at a constant speed, and it only looks like they accelerate because we can't see all 4 dimensions. (the 4th dimension is time). My understand is that Newtonian gravity does not explain the existence of black holes or why light would bend in a gravitational field (because light has no mass).

I saw some posts that said you can directly perceive matter. I think that is utter nonsense. You don't directly perceive something unless you experience it with one of your senses. As far as I am aware, we have no sense which tells us the mass of an object, which is why we need to weigh things (although weight isn't strictly the same as mass, it's the force of gravity that comes from the mass of an object. weight is the F in the F = ma equation and m is the mass, and a would be the acceleration of gravity, which is constant near the earth's surface.). I believe the closest you can come to sensing any of these things is energy because we can tell when we are accelerated because we have fluids that slosh around in our bodies when we do. But we aren't actually sensing energy when we are accelerated, we are sensing a change in energy.

Now this is more philosophy than physics. I think Hume is one of the first people to express these ideas about space and time. My understanding is that we cannot perceive space directly. If we could, we would be able to perceive distance by staring up at the empty night sky. Distance does not make any sense to us unless there are objects in space that we can compare with each other. The only thing we can sense are the objects (indirectly through light), so the idea of distance we have in our heads is something we create out of the images we see. We cannot directly perceive time either. We think of time as a change in the condition of things. You could imagine that if you saw a video of a car going down a road and it sped up, you would have no way of knowing whether the car actually went faster or someone played the video at a higher speed. So the only things we actually see are objects, we compare the relation of the objects to create the idea of space in our minds, and the rate of change of the place or condition of the objects is what we perceive as time.

I hope you like this explanation

matter and energy are the same thing. THey're both two sides of the same coin.
Space and time aren't exactly the same thing, but they can rotate into each other, just like if you have a rectangular prism, and you turn it, length can become height. length can become time, too, somehow. Through relativity.
As for gravity, it's not the same as any of these things (which is understandable, because gravity quite often finds itself the odd man out). According to general relativity, it's the product of matter-energy curving space-time.

There is no gravitation.

Gravitation is just matter warping space.

"Matter tells space what shape it is, and then space tells matter how to move (ie how the planets should orbit the sun etc)."

Thats how it is often explained.

Matter warps space because matter has mass.
And then lumps of matter ( like planets) move through that warped space in magestic orbits.

So there is no gravitation. Its an illusion because its really matter warping space because matter has mass.

But matter doesnt REALLY have mass.
Thats also an illusion.

Matter gets mass from the higgs boson.

The higgs boson is a particle that prevades empty space.

So matter gets its mass from...interacting with empty space.

So matter interacts with empty space- causing matter to have mass- which in turn causes matter to shape empty space which in turn causes the empty space to force matter to move in the way matter has sculpted empty space because empty space tells matter how much mass it has so matter can scupt the empty space that matter has to move through. In short-empty space tells matter how to sculpt empty space so empty space can tell matter how to move through empty space.

So ... matter is just a tool.. for empty space to sculpt itsself!

So...space and matter are basically a pair of kinky lovers. Space is the masochistic woman who orders matter to "beat me, bend me, shape me".

And matter obeys because it wont get any if it doesnt play along.

So matter APPEARS to be in control because its standing over space wielding the whips and beating space, but its really space that calls the shots!

Does that make any sense?

If so...then maybe you can explain it all to me!

Gravitation is a force, that warps space and matter. Notice how many things are ball shaped?

I see it as gravity/time, somehow driven by matter.

Now matter cannot have the mass it has, without a Higgs Boson, and the Universe without Dark Matter and Energy.

I think Dragons, or bad Math.

It is all Star Barf anyway.

Which came first, Hydrogen, or Hydrogen?

Primate brains are not made for this stuff.