Energy And Fields - What are they?

[bilby]

In terms of philosophy and science fiction energy is anything you imagine it to be.

Not really. Energy is the ability to do work; That is, to accelerate a mass, or to lift it against the acceleration due to the local gravitational field. It's a force applied over a distance.

I think they ignore gravity to much.

Who is ignoring gravity ?

And time is an issue. I don't think its a dimension.

Well, you're in good company, Newton was a deadset genius, and he made the exact same mistake. And it's such a minor mistake that nobody noticed for almost three hundred years, and even then only because some nerds wanted to achieve incredible precision in their predictions of the orbit of Mercury.

dt is a math trick to me.

Well any change in any quantity could be viewed that way. But it has real, measurable consequences - so it's clearly more than just a math trick.

But then again, I dont know what I dont know. I just know its a lot.

You, and every other person who has ever lived.

 

[bilby]

I wonder what would happed if we could stop, relative to "space". Like absolutely.

Your “relative” and “absolutely” are in conflict. Which frame of space would you consider to be “absolute”?

Implicit in the question is the assumption that there's one (and only one) absolute spatial reference frame, and that all others can be measured relative to it. That's an assumption that worked extremely well for all of human history up until the 1720s, and wasn't seriously and systematically questioned until the 1883 publication of Mach's Science of Mechanics, which led to Einstein's two theories of relativity in the early twentieth century, and culminated in the experimental demonstration by Eddington et al. of relativity, by observation of the effect of the Sun's mass on spacetime during the total eclipse of 1919.

 

[SIB]

I wonder what would happed if we could stop, relative to "space". Like absolutely.

Your “relative” and “absolutely” are in conflict. Which frame of space would you consider to be “absolute”?

Yeah, you are correct .... that is the issue isn't it.

Lets just take earth's motion as the reference. I "stop" relative to "I don't know". The solar system wizzes away at around 0.5x10^6 mi/hr in some direction(s).

Assume I am on the side of the earth that doesn't crush me when I stop that is. Or should I say ... tries to accelerate me to quickly? Please forgive the "misspelling" in the speed.

 

[steve_bank]

If you ask me what speed or velocity is I'll say it is meters/second. If yiou ask me what force is I' sat mass times acceleration defined in kilograms, meters, and seconds. If you ask me what energy is the same response in meters, kilograms, and seconds. For some reason some have no trouble with velocity but go off on a tangent with energy.

 

[SIB]

In terms of philosophy and science fiction energy is anything you imagine it to be.

Not really. Energy is the ability to do work; That is, to accelerate a mass, or to lift it against the acceleration due to the local gravitational field. It's a force applied over a distance.

I think they ignore gravity to much.

Who is ignoring gravity ?

And time is an issue. I don't think its a dimension.

Well, you're in good company, Newton was a deadset genius, and he made the exact same mistake. And it's such a minor mistake that nobody noticed for almost three hundred years, and even then only because some nerds wanted to achieve incredible precision in their predictions of the orbit of Mercury.

dt is a math trick to me.

Well any change in any quantity could be viewed that way. But it has real, measurable consequences - so it's clearly more than just a math trick.

But then again, I dont know what I dont know. I just know its a lot.

You, and every other person who has ever lived.

"Ignoring" is really "Canceling it out". Everything we experience happens in a gravitational field. I am not sure just canceling it out is the path to unifying QM and Einstein. But I am out of my league here. So I happy to listen to anything you have you have to offer.

I don't want to appeal to authority here but I think Penrose has a point. But honestly, I don't know enough at this point.

 

[SIB]

If you ask me what speed or velocity is I'll say it is meters/second. If yiou ask me what force is I' sat mass times acceleration defined in kilograms, meters, and seconds. If you ask me what energy is the same response in meters, kilograms, and seconds. For some reason some have no trouble with velocity but go off on a tangent with energy.

You have a point ... we can use it.

Like driving a car. The average person doesn't need to the mechanism. They just push the pedal. But that doesn't mean we ignore "what is is".

It really only comes into play when we start telling people they have to follow laws based on not knowing how the car works. When people that do know how it works start to say "stuff" and people that don;t know, or are "anti-car" start thinking they have equal understanding past the end of their nose.

 

[steve_bank]

Soldier

First and foremost energy is not a thing, it is not any kind of independent existence. That is a scifi fiction.

Did the physics class you took cover work and force?

From physics
Force = Mass * Acceleration
F= m*a = Newtons

Work = Force * Distance
Work = F*meters = Newton Meters

Push a rock and you have done work. The energy equivalent in Joules is force applied in Newtons* distance in meters.

Energy E is defined as the 'capacity to do work'. Anything that can be used to do work is said to have energy. The unit of energy, heat, and work is the Joule.

Some coal might have 1000 Joules of energy. An amount of natural gas might have 1000 Joues of energy. A piece of wood might have 1000 Joules of nergy.

If all the energy in each is converted to heat all three sources will raise the temperature of an amount of water the same number of degrees.

Propane has energy. Put a pot of water on a propane gas stove and it warms up.

Where is the 'energy'? Can you point to it? Energy is an abstaction to derbe a process, and is qunfied into a unity of measure.

Same as meters and kilograms. You can't get a bucket of meters or kilograms. The terms are abstractions. You can take a meter stick and quantify a distance in meters.

Likewise there are methods to quantify in Joules the energy, or capacity to do work, of a substance or phenomena.

You can't get a bucket of energy, you can get a bucket of coal which is said to have energy.
To say something has energy is to say it can be used tdo work, like boil water or move a car.

Moving electrons in a wire is work, force*distance.


Read and ponder before responding. As things go this is about as basic as it gets.