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Posts Tagged ‘space’

This is an exercising post. I want you to stand up and try the following:
Look at your clock.
Jump. You probably moved up and down.
Slide left. Slide back to the right.
Slide forward. Slide backward.
Stand still.
Step left. Step right. You probably moved both up-and-down and left, up-and-down and right.
Look at the clock. How much time has passed?

Refer back to your exercises to help you answer the following questions.
Can you move in one dimension?
Can you move in two dimensions?
Can you move in three dimensions?
Can you do any of those without moving through time?

In science today, there are four accepted dimensions. We tend to call these space-time. There are three spatial dimensions (sideways, forward, vertical), and one dimension for time. These four dimensions are connected, sometimes in mysterious ways allowing for the concepts of wormholes and time travel. More practically, these connections are used in Einstein’s famous Special Theory of Relativity and General Theory of Relativity, which are applied all over physics today with some very helpful results.

I don’t know if this is Einstein’s own illustration, or some textbook writer’s, but the principle belongs to Einstein’s Special Theory of Relativity: Time is relative. This is proven, supposedly, by the fact that if you were to throw a clock at the speed of light (something no one has done), the hands would shorten, and thus they would travel the dial at a different speed. Since we use a clock to measure time, obviously time is relative to the speed at which one is traveling. That is what a physics book once taught me. What nonsense! The measurement of time does not equal time. Time is not contained in the length of the hands on a clock; it is described by them. So while I’m not arguing necessarily that time is not relative, I am saying that the reasons we think it is are less than persuasive.

In the very least, we ought not classify time in the exact category as the spatial dimensions, because, as shown, we can move in any one of those dimensions without moving in another one. We can also move in two or even three of those dimensions, but the choice is ours. Human experience has not produced a circumstance in which anything has moved in a spatial dimension without moving in time. In fact, we cannot even fail to move spatially and keep ourselves still in the “dimension” of time. Hypothetically we could stand still in time, moving outside of time or existing without time. But there is no observational evidence of this phenomenon.

So I remain a little skeptical of the description of our universe as four-dimensional (let alone boasting more dimensions, as some theoretical physicists like to suggest). How tied is our matter and energy reality to time? What is time? Is it linear? Does perception define time? What is the meaning of action, thought, or existence outside of time? Can time really accelerate? Can it change direction? Some physicists are suggesting, based on observations, that space is actually stretching. Can time stretch?

To God be all glory,

Lisa of Longbourn

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Lately I’ve been in a state of mind that can soak up information, and comes up with really good questions – well I think they’re interesting, leading me to more and more questions (and occasionally to comprehension).  One field that’s been appealing this week is physics.  I’m reading a book, Reinventing Gravity, that has me thinking about the basics of physics – and marvelling at how much of our universe we humans don’t understand. 
 
So I would be ok with exhaustive comments answering the following questions, or referrals to books or websites that could help me understand these things.  I took physics in high school, no problem, and have given a great deal of skeptical thought to Einstein’s Special Theory of Relativity.  This is because I’m fairly convinced the speed of light is not constant.  So if you mention the speed of light in your answer, I’ll probably enjoy it more.  I understand that I’m missing a few levels of knowledge between high school physics and the edges of theoretical physics I’m trying to reach.  Give me your best shot. 
 
You can also use the comment section to add your own questions.  The compilation of questions is great food for thought and theory. 
 
Some physics questions:
Are forces energy? 
What is light? 
     Does it have a constant velocity? 
     Is its speed constant? 
     If the velocity of light is not constant, what force acts on it? 
          What is the equal and opposite reaction? (Whence is the energy subtracted?)
 
What is electricity? 
What is magnetism?
 
What is heat? 
     Is it motion in and of molecules,
     or that which causes motion in and of molecules,
     or the output of motion in and of molecules?
 
What is gravity? 
How is gravity related to attraction and acceleration (gravitational mass and inertial mass)?     
     What is the significance of the relationship? 
     Does the resistance or escape of an object from gravity take any energy away from the gravity-exerting objects? 
     Does gravity curve space, or is it the effect of curved space? 
 
If gravity is the effect of curved space, what makes space curved? 
     Matter and energy? 
     Is anything else (such as time) curved by these things as well? 
     If spacetime can be curved, what else can be done to it? 
 
Can spacetime be stretched? 
     If spacetime can be stretched, what stretches it? 
     Are opposing forces of gravity like Curling brooms, creating a smooth path for matter and energy? 
 
 
How do permittivity and permeability relate energy, electricity, gravity, and matter? 
     What does density have to do with them? 
     What force causes nature to abhor a vacuum?  
 
 
(To quote The Little Mermaid), What is fire and how does it burn? 
     Must fire produce light? 
     Can light be produced without fire/burning? 
     Must fire produce heat? 
     Are there other ways to convert matter to energy? 
 
Oh my goodness, does time have to come into this? 
     How is time related to the measurement of time? 
          Must there be a direct correlation?
 
To God be all glory,
Lisa of Longbourn

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