General Discussion

DetlefK

(16,670 posts)

40. Time is exactly not that.

Tue Dec 11, 2012, 10:44 AM

Dec 2012

Example:
The edges of your desk are a coordinate-system. Height, length, width. (3 dimensions!)
Now take a piece of paper. (2 dimensions!)
You can rotate the paper, so its plane is vertical to the height-axis. Now the 2-dimensional object has no vector-components relating to the height-axis. For this object, height no longer exists.

If time were just another dimension, the same would work with time instead of height:
This time take a coordinate-system with 4 dimensions, time+space, and a 3-dimensional object.
Can you rotate the object in a way that it stops being subject to time?

That's the reason why spacetime is always referred to as being (3+1)-dimensional: Time and space don't mingle.

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Alan Alda poses question in new contest for scientists: What is time? [View all] The Straight Story Dec 2012 OP

Time is tama Dec 2012 #1

Wait for it .... rock Dec 2012 #34

The suspense is killing me... Xipe Totec Dec 2012 #54

... tama Dec 2012 #66

Softly Xipe Totec Dec 2012 #68

So there's your answer, mr. Alda: tama Dec 2012 #69

We knew what time was back in the 50's. I think it goes like this: rhett o rick Dec 2012 #50

11:00 am johnp3907 Dec 2012 #70

Then why does your post say 10:00am here in the Midwest? Liar! randome Dec 2012 #71

I'm a time traveler. johnp3907 Dec 2012 #81

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25 or 6 to 4 nt Javaman Dec 2012 #38

Cue the trumpets. nm rhett o rick Dec 2012 #49

Our concept of time is totally wrong. kentuck Dec 2012 #3

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Time is an illusion. Lunchtime doubly so - Ford Prefect Xipe Totec Dec 2012 #82

I like to play with the concept of time leftyladyfrommo Dec 2012 #5

All I know is Love Bug Dec 2012 #6

I always thought that time and space are constructs Quantess Dec 2012 #7

If we truly don't experience everything all at once (as it appears we don't). EOTE Dec 2012 #43

Time is what keeps everything from happening all at once n/t eridani Dec 2012 #8

Alan Alda's question, "What is a flame?", always fascinated me as a child. Jim__ Dec 2012 #9

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Wow .Well explained. Especially the mnemonic song at the end Tanelorn Dec 2012 #21

Yes, a child could understand this BUT... SkyDaddy7 Dec 2012 #27

I totally agree. avebury Dec 2012 #25

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Really? Who cares? napkinz Dec 2012 #11

Toughie. You can't really even define a second. It depends how fast you're going. tclambert Dec 2012 #12

I ascribe to your last explanation Madam Mossfern Dec 2012 #17

Ooooo, my favorite episode Occulus Dec 2012 #74

great 60s song by The Chamber Brothers napkinz Dec 2012 #14

Time is our realization that more than two similar movements occurred. Festivito Dec 2012 #15

The conjugated variable to energy. :D DetlefK Dec 2012 #18

That was my first thought as well VWolf Dec 2012 #20

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Time is a way of counting the rotations of the earth Marrah_G Dec 2012 #23

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time is the forward flow of our existence shireen Dec 2012 #26

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The Fourth Dimension Taverner Dec 2012 #79

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