Fed up with rising gas and electricity prices?

[wendigo100]

Just as time is the fourth dimension, space is the fifth, for space is completely boundless and knows no time. There, I hope that's clear.

As I understand it, space is the first, second and third dimensions, by definition. What is this fifth dimension?

Time is always the same for everything and everyone. Nothing can travel backwards in it. Don't we just pretend it is a dimension for practical reasons like scheduling, applied maths and stuff?

[Fungus]

As I understand it, space is the first, second and third dimensions, by definition. What is this fifth dimension?

Time is always the same for everything and everyone. Nothing can travel backwards in it. Don't we just pretend it is a dimension for practical reasons like scheduling, applied maths and stuff?

Kaluza Klein theory postulated a fourth spatial dimension, coiled up on itself:

http://www.matter-antimatter.com/kal...ein_theory.htm

Modern string or brane theory further increases the number of spatial dimensions.

"Don't we just pretend it is a dimension for practical reasons"

Depends what you mean by pretend. We make lots of assumptions in order to derive theories which agree - or not - with experiment. General relativity and other theories model time as a dimension and they are very successful. If string theory can be used to make predictions, or to derive the values of the cosmological constants, then it's not really pretending.

I suppose we could collectively put our fingers in our ears and shout "Can't hear you" whenever a theoretical physicist spouts off. (If you work in theoretical physcis it feels like that anyway.)

[DimPrawn]

I believe there are 42 + 7i dimensions

This is where the answer to life the universe and everything comes from and also why most peoples lucky number is seven.

HTH

[wendigo100]

"Don't we just pretend it is a dimension for practical reasons"

Depends what you mean by pretend. We make lots of assumptions in order to derive theories which agree - or not - with experiment. General relativity and other theories model time as a dimension and they are very successful. If string theory can be used to make predictions, or to derive the values of the cosmological constants, then it's not really pretending.

That's what I meant, yes. We used to model the universe with gods and the supernatural in order to make sense of it, and they were very successful in their day too.

Are strings the new goat entrails?

[sasguru]

That's what I meant, yes. We used to model the universe with gods and the supernatural in order to make sense of it, and they were very successful in their day too.

Are strings the new goat entrails?

There is a big difference between religious/supernatural and scientific methods of modelling the world. The former doesn't allow contradiction, while the latter does - waiting till a better model comes along. Thus by small increments we get closer to the truth (with occasional Kuhnian shifts). It is ironic that the greatest flowering of science in the latter half of the 20th Century also coincided with the "invention" of post-modernism, IMHO the revenge of the stupid for the humiliation they had to endure at school.

PS Your earlier post is also wrong. According to all the Maths (and I think some empirical evidence) it is possible to go back in time, which is just another dimension in the space-time continuum.

[sasguru]

Understands what, exactly? Please elucidate.

Does he understand that making smug-sounding comments of the "Ah ha! I know better than you Pygmies" sort, without bothering to explain his own 'theory' to the rest of us benighted plebs makes him look like an utter tosser?

Agreed. Threaded is a fraud and a sad one at that.

[wendigo100]

According to all the Maths (and I think some empirical evidence) it is possible to go back in time.

[Fungus]

Actually he's right. Recent theoretical studies have shown that going back in time would be possible and would not violate current physics. As to how you do it, well just read posts by Chico and Knob Jockey. Well, at least it feels like you're going back in time.

[sasguru]

It's always amusing when people reveal their ignorance

[EternalOptimist]

It's always amusing when people reveal their ignorance

sorry to disagree but I find it more amusing when people reveal their willies