Simplified spacetime and Emc2 vs Quantum Theory

JackWilkinson
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"simplified" spacetime and Emc2 vs Quantum Theory

I tried to post this in the textbook or homework section but it kept saying i was not allowed? So, to attempt to keep to the rules of the site i will ask my question but also try and start a discussion to try and keep things interesting.

Ive only recently been reading about maths and physics although I've always been interested in them. Unfortunatly my maths is pretty bad but I am determined to impove it.

I would also like to note that i am not doing any courses or exams and that this is purely out of interest.

After reading about spacetime i was trying to work out the spacetime distance between two towns or more to the point the spacetime distance you would make on the journey between the two towns, if we break it down into different points of the journey ie: walking to bus stop from your house, waiting for the bus, traveling on the bus, walking to train station, waiting for the train, journeying on the train etc.Is there a "simplified" (for lack of a better word) way of calculating spacetime distance?Ive been working on it on and off but i feel overwhelmed, I am quite confident with the theory behind spacetime but as usual I am having problems with the math and things are not adding up (as far as i can tell). Thank you to anybody who has any suggestions or responses.
 
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JackWilkinson said:
[..] I've only recently been reading about maths and physics although I've always been interested in them. Unfortunatly my maths is pretty bad but I am determined to impove it. [..]
After reading about spacetime i was trying to work out the spacetime distance between two towns or more to the point the spacetime distance you would make on the journey between the two towns, if we break it down into different points of the journey ie: walking to bus stop from your house, waiting for the bus, traveling on the bus, walking to train station, waiting for the train, journeying on the train etc.

Is there a "simplified" (for lack of a better word) way of calculating spacetime distance?[..]
Hi Jack, it's best to focus on one precise question at a time. :smile:

Spacetime is mathematics or geometry that is used as a tool in physics, even by different physical theories. See:
https://en.wikipedia.org/wiki/Spacetime

That same article also tells you how to calculate so-called "spacetime intervals", which are used in relativity theory:
https://en.wikipedia.org/wiki/Invariant_interval#Spacetime_intervals

It may be helpful if you state what you understood of its use in physics - do you understand what "invariance" means in this context?
 
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