  # Dimensions of Space and Gravity

## Does Gravity Cause Spacetime Curvature?

Many people think space and time are curved. Spacetime has a curvature in the mathematical path of motion, which is easily explained, but gravity doesn’t cause spacetime curvature. Einstein said the curvature only describes how particles move towards gravity.

## Spacetime Curvature

The motion of particles toward a massive object follows a curved path according to Einstein’s general relativity.

Einstein’s theory describes the trajectory that particles follow as they accelerate to a massive object such as the Sun.

Minkowski spacetime is a geometric description of motion using Einstein’s equations to describe the path of acceleration toward a force of gravity. The theory isn’t a physical curvature of space; it's a mathematical description of the path of motion.

As a particle moves closer to the Sun, it moves faster and faster because of the acceleration force of gravity. The particle's path moves in a geometric curve caused by the power of gravity.

On Earth, when you drop something, it falls straight toward the center of the Earth, and Newton’s law of gravity describes the acceleration.

If you throw a ball, it follows a geometric curve towards the center of Earth, but because the speed of the ball is slow, its curvature is still described by Newton’s laws of gravity.

In space, particles move at relativistic speeds to the Sun, and Newton’s laws don’t account for the speed and effects of time dilation measurements.

Einstein imagined that light moving past the Sun must be experiencing time dilation, causing light to follow a curved path.

Then Minkowski described the effects as space and time curvature, but Einstein said it wasn't meant to be a physical curvature.

The mathematical description describes the path in space but not because of curved space.

How did we end up thinking that space is curved? If a mathematical description is treated as a physical thing, that’s what happens.

I hope more scientists will think independently instead of believing what was taught.

A mathematical system can't prove its operation without referring to something outside itself.

## What's the difference between General relativity and the Rubber sheet example?

The following descriptions explain the difference between general relativity and a rubber sheet.

A rubber sheet will curve when a heavy object rests on it because of the force of gravity. This is a visual description of the effect caused by gravity, not by the curvature of the sheet.

General relativity is a mathematical description of an object as it follows a curved path toward a force of gravity.

Relativity describes the path, but it’s not a physical path in space.

So we have a visual and mathematical description of the effect of gravity to describe what we observe. But descriptions aren’t actual physical things.

Rubber is a material that curves, but space isn't material. Neither model addresses the force nor the source of gravity.

When will we realize that mathematical descriptions of relativity are not physical things?

Gravitational fields do not cause spacetime curvature; space and time are massless invisible concepts used to describe the physical world we see.

If something causes spacetime to curve, show the force that causes it.

Spacetime is a geometric description of particles moving toward a massive force of gravity, such as the Sun.

Therefore, being a description of movement, it cannot be a fabric or a curvature of spacetime. Descriptions are not physical things.

Four years ago, Alexander Poltorak, a scientist on Quora, accurately described spacetime.

“Gravity is a physical phenomenon. The curvature of spacetime is an abstract mathematical concept. Some philosophers might argue that, whereas gravity exists in nature, spacetime curvature exists in our minds. Gravity is an intrinsic property of nature. The curvature of  spacetime is a mathematical model.”  -- How can it be anything else?

## Do Scientists Maintain Only the 3rd  Dimension Exists?

The different meanings of dimensions may mislead you. Scientists only recognize the three spatial dimensions of direction and the temporal duration of time.

Science fiction books and movies use dimensions to mean other realms of existence, such as a parallel universe or 4th and 5th dimensions.

String theory suggests that up to 10 dimensions exist as small, curled-up things. Let me explain how to make sense of it.

Dimensions are descriptions and measurements of things, and there are only three spatial directions (up-down, left-right, and in-out) to describe matter.

In string theory, dimensions aren’t different sizes because the strings exist as levels of energy, not as sizes of energy.

To describe matter, you can measure its mass, temperature, color, or energy.  Matter can exist as plasma, gas, liquid, or solid.

Since matter comes in 4 different energy states, we could use energy to describe matter by its energy state.

A phase transition separates the energy levels of matter. Most of the matter in the universe is plasma, which is the energy state of stars.

If the universe has other energy-level dimensions or realms that are invisible to us, they would be in a different "energy state."

For example, water can be a solid or liquid, but a single molecule of water can’t be both at the same moment. It’s either liquid or solid.

The universe has energy states that are different than the 3rd dimension that we know. It’s difficult to explain using words that don’t exist in scientific language.

But scientists know that matter has four energy states, so maybe the Universe has more energy levels "states" instead of the single 3rd dimension.

What about Dark matter and energy that makes up most of the matter and energy in the Universe? Scientists can't find any of it in our 3rd dimension, so they should consider other possibilities.