Hi, im back again I was just wondering whether science accepts time as being a 4th dimension or if it is still open for debate (not that I want to debate, I just need clarification). Also, with time dilation, why does science think that a more energetic (faster) object experiences (or appears to experience) time slower relative to a less energetic object. Is this an area of thought largely ignored due to the "why bother its useless to think about it" factor?
According to the special relativity which hasn't yet been formally disproved, time is the 4th dimention. It's an integral part of the space-time fabric. Space cannot exist without time and vice versa. About time dilation, it actually makes sense. Read the first chapter in any book about relativity and it's there. You'll get it. It's all just some imagination followed by algebra which gives you a formula which makes science think that time dilation occurs. A search in google will also give you some interesting basic articles.
Hoodlum: <i>I was just wondering whether science accepts time as being a 4th dimension or if it is still open for debate...</i> Time can be considered to be a fourth dimension. You need to be careful how you use the word "dimension". Sometimes it means no more than "variable". Sometimes it refers specifically to a spatial dimension. When people talk about "the 4th dimension", they are usually talking about a 4th <b>spatial</b> dimension, not about time. <i>Also, with time dilation, why does science think that a more energetic (faster) object experiences (or appears to experience) time slower relative to a less energetic object.</i> Energy has nothing to do with it. Also, the object doesn't experience any change in its own measurements of time. The only measurements of time which are different are those made by observers in relative motion watching the object. <i>Is this an area of thought largely ignored due to the "why bother its useless to think about it" factor?</i> No.
Multi dimensions Lets get the facts straight. The 4th dimension you are referring to IS NOT SPATIAL. All that was done is that instead of representing space as a 3 dimensional vector and time as an independant term, time was incorporated into the vector as either the first or last term(depending on the representation). It still has all the characteristics of time.
Here is a site that explains time dilation in just a few sentences. Time dilation follows from the speed of light being constant.
Stupid me Please Register or Log in to view the hidden image!. I didn't see the link. Thanks for the site.
Read Michael Chrichton's Sphere it talks all about it, actually some scientists think that time is in the 4th dimension, but some also think the 4th dimension is broken up into 8 other dimension, and the 8th dimension adjourded to the 4th is borked down... so on so on
Okay so science interchanges between referring to time a 4th spatial dimension and a 4th vectorial dimension... Thanks for clearing that up. I think my question about time dilation is misunderstood. I know what time dilation is observed to be - a slowing down of time for relatively faster objects. Simple. I was just wondering if science looks into how the slowing down of time occurs when an object moves faster, and I know we are speaking in relative terms here when I say "faster" I mean "faster relative to me". Also I think you'll find that faster means more energy.
Sorry about the clarity of my questions I spend most of my time talking about science with non scientists so its hard to switch between the different ways of interacting with people... I might need to add more clarity it depends on whether or not I've asked the question the right way (doh).
If I'm understanding you correctly, Hoodlum, you're asking "<I>why</I> does time dilation happen?" It's a consequence of one of the postulates of special relativity - that the speed of light will be measured to be the same by all inertial observers. Think of it this way: suppose you're standing on the back of a flat-bed truck. The truck's moving along at some speed v. You throw a ball forward at some speed u. What's the speed of the ball relative to the ground? Your answer would (I presume) be w, where w = u + v. Now suppose that instead of throwing a ball, you fire a laser pulse forward. The pulse travels away from you at speed c. The truck is still moving at v. What's the speed of the laser pulse relative to the ground? Again you would say w, where w = c + v. But that's the Newtonian answer, and Einstein say's it's wrong. He says that the observer on the ground will <I>also</I> measure the speed of the light pulse to be c. So w = c. Which means w = c = c + v. How can c = c + v, if v is not 0?? The obvious answer is that the relation w = c + v is wrong - and so it is. The postulate of special relativity about all observers measuring the same speed of light forces us to change our understanding of distance and time. These are no longer absolute, they must change with velocity in order to accommodate a constant speed of light. The result is the time dilation, and the Fitzgerald length contraction. You can derive the relaiton for yourself by considering a photon bouncing backwards and forwards between two moving mirrors. It's quite an educational exercise.
