# What do you believe?

Dexter Sinister
#91
Quote: Originally Posted by Jay

Quote: Originally Posted by zenfisher

I tend to view it as sixth dimesional including length, width, height, space, time and gravity.

But isn't space and time the same thing, and isn't gravity a bent of that fabric called space time?

This begs for some clarification, and a little simple algebra might help. Length, width, and height define space, in a sense, at least the space our senses perceive. Relativity theory adds another dimension based on time and the speed of light that we can't perceive directly, essentially because the speed of light is so huge, and the result is called spacetime. You're familiar with the notion of specifying a location in space in terms of three numbers, usually called x, y, and z? For instance, you could say some location is x meters north of you, then y meters west, then z meters above the ground. You've implicitly defined a coordinate system with yourself at the zero point of all the dimensions. We also know that the straight line distance from you to that location is given by the square root of the sum of the squares of x, y, and z, by a simple extension of the Pythagorean theorem about the sum of the squares on the sides of a right triangle.

At least in the intuitively familiar world of Euclidean geometry. that's the way it is. Relativity adds a fourth term to that calculation, to account for the fact that you're also separated in time from that location. In Euclidean terms you calculate what's called the space interval, usually called s in most references I've seen, as s²=x² + y² + z². In relativity theory you calculate the spacetime interval as s²=c²t² - (x² + y² + z²), where c is the speed of light and t is time. It has to be done that way or different observers won't agree on where things are or when they happen.

In general relativity, we find that those coordinate axes along which we measure x, y, and z are not straight lines, but curves defined by the distribution of mass, which is what leads to the notion that gravity is a distortion in the shape of space caused by masses. So no, space and time are not the same thing, they're parts of one thing, and there are not six dimensions in relativity theory, there are four, which define spacetime, and the presence of masses changes its shape.

Dexter Sinister
#92
Quote: Originally Posted by Jay

Quote: Originally Posted by zenfisher

I tend to view it as sixth dimesional including length, width, height, space, time and gravity.

But isn't space and time the same thing, and isn't gravity a bent of that fabric called space time?

This begs for some clarification, and a little simple algebra might help. Length, width, and height define space, in a sense, at least the space our senses perceive. Relativity theory adds another dimension based on time and the speed of light that we can't perceive directly, essentially because the speed of light is so huge, and the result is called spacetime. You're familiar with the notion of specifying a location in space in terms of three numbers, usually called x, y, and z? For instance, you could say some location is x meters north of you, then y meters west, then z meters above the ground. You've implicitly defined a coordinate system with yourself at the zero point of all the dimensions. We also know that the straight line distance from you to that location is given by the square root of the sum of the squares of x, y, and z, by a simple extension of the Pythagorean theorem about the sum of the squares on the sides of a right triangle.

At least in the intuitively familiar world of Euclidean geometry. that's the way it is. Relativity adds a fourth term to that calculation, to account for the fact that you're also separated in time from that location. In Euclidean terms you calculate what's called the space interval, usually called s in most references I've seen, as s²=x² + y² + z². In relativity theory you calculate the spacetime interval as s²=c²t² - (x² + y² + z²), where c is the speed of light and t is time. It has to be done that way or different observers won't agree on where things are or when they happen.

In general relativity, we find that those coordinate axes along which we measure x, y, and z are not straight lines, but curves defined by the distribution of mass, which is what leads to the notion that gravity is a distortion in the shape of space caused by masses. So no, space and time are not the same thing, they're parts of one thing, and there are not six dimensions in relativity theory, there are four, which define spacetime, and the presence of masses changes its shape.

Dexter Sinister
#93
Quote: Originally Posted by Jay

Quote: Originally Posted by zenfisher

I tend to view it as sixth dimesional including length, width, height, space, time and gravity.

But isn't space and time the same thing, and isn't gravity a bent of that fabric called space time?

This begs for some clarification, and a little simple algebra might help. Length, width, and height define space, in a sense, at least the space our senses perceive. Relativity theory adds another dimension based on time and the speed of light that we can't perceive directly, essentially because the speed of light is so huge, and the result is called spacetime. You're familiar with the notion of specifying a location in space in terms of three numbers, usually called x, y, and z? For instance, you could say some location is x meters north of you, then y meters west, then z meters above the ground. You've implicitly defined a coordinate system with yourself at the zero point of all the dimensions. We also know that the straight line distance from you to that location is given by the square root of the sum of the squares of x, y, and z, by a simple extension of the Pythagorean theorem about the sum of the squares on the sides of a right triangle.

At least in the intuitively familiar world of Euclidean geometry. that's the way it is. Relativity adds a fourth term to that calculation, to account for the fact that you're also separated in time from that location. In Euclidean terms you calculate what's called the space interval, usually called s in most references I've seen, as s²=x² + y² + z². In relativity theory you calculate the spacetime interval as s²=c²t² - (x² + y² + z²), where c is the speed of light and t is time. It has to be done that way or different observers won't agree on where things are or when they happen.

In general relativity, we find that those coordinate axes along which we measure x, y, and z are not straight lines, but curves defined by the distribution of mass, which is what leads to the notion that gravity is a distortion in the shape of space caused by masses. So no, space and time are not the same thing, they're parts of one thing, and there are not six dimensions in relativity theory, there are four, which define spacetime, and the presence of masses changes its shape.

merryclaire
#94
I believe in love at first sight

I believe that most marriages don't start out that way and instead it takes a lot of work, compromise and respect

I believe in the power of love
I believe in the power of respect
I believe in the power of truth
The Holy Trinity, as it were

I believe that love is the most easily attainable as it is the easiest to give or receive, taking little and gaining lots
I believe that trust and respect take hard work and are more selfless

I believe that many people never give any

Finally, I believe, that if each one of us gave a little, this world would be a damn fine place to live in

merryclaire
#95
I believe in love at first sight

I believe that most marriages don't start out that way and instead it takes a lot of work, compromise and respect

I believe in the power of love
I believe in the power of respect
I believe in the power of truth
The Holy Trinity, as it were

I believe that love is the most easily attainable as it is the easiest to give or receive, taking little and gaining lots
I believe that trust and respect take hard work and are more selfless

I believe that many people never give any

Finally, I believe, that if each one of us gave a little, this world would be a damn fine place to live in

merryclaire
#96
I believe in love at first sight

I believe that most marriages don't start out that way and instead it takes a lot of work, compromise and respect

I believe in the power of love
I believe in the power of respect
I believe in the power of truth
The Holy Trinity, as it were

I believe that love is the most easily attainable as it is the easiest to give or receive, taking little and gaining lots
I believe that trust and respect take hard work and are more selfless

I believe that many people never give any

Finally, I believe, that if each one of us gave a little, this world would be a damn fine place to live in

peapod
#97
Merryclaire is also the sweetest person you could ever meet

peapod
#98
Merryclaire is also the sweetest person you could ever meet

peapod
#99
Merryclaire is also the sweetest person you could ever meet

Twila
#100
I don't know about your claim Pea. My daughters Aunt ( ex inlaw side) is the sweetest. kindest. most wonderful person I've had the fortune to know........Could there be 2 in this world?

Twila
#101
I don't know about your claim Pea. My daughters Aunt ( ex inlaw side) is the sweetest. kindest. most wonderful person I've had the fortune to know........Could there be 2 in this world?

Twila
#102
I don't know about your claim Pea. My daughters Aunt ( ex inlaw side) is the sweetest. kindest. most wonderful person I've had the fortune to know........Could there be 2 in this world?

peapod
#103
maybe even 4....if you count me :P

peapod
#104
maybe even 4....if you count me :P

peapod
#105
maybe even 4....if you count me :P

merryclaire
#106
definately 4!!

merryclaire
#107
definately 4!!

merryclaire
#108
definately 4!!

peapod
#109
thanks...I pass you that twenty next time I see you :P

peapod
#110
thanks...I pass you that twenty next time I see you :P

peapod
#111
thanks...I pass you that twenty next time I see you :P

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