Horrendous creationist errors

[MartinM]

Someone in another thread linked to this site, which purports to refute Mark Isaac's ICC. Needless to say, the responses are the usual drivel; but some in particular leap out as even more hideously wrong than the average creationist argument. Take a look at this one; in which one intrepid creationist identifies potential energy with its own negative and ends up implicitly rejecting conservation of energy. It's kind of Humphreys-esque ignorance of the physics under discussion, only on a very basic level. This is high school stuff!

"This response is seriously flawed"

Yeah. Thanks for the warning.


So, could this be the single worst physics error a creationist has ever made? Can anyone think of anything more fundamental than mangling the definition of potential energy?

 

[tryptophan]

It isn't E=fd, it's W=fd (right?) where W is work. And work can be negative! That is awful.

 

[MartinM]

Right, the work done in a force field is given by the path integral of F.ds, which is simply the negative of the change in potential energy. Though actually, having screwed that up, he then goes on to use the correct expression for potential energy, but sticks in a minus sign in his definition of gravitational force. That leads him to the conclusion that when I drop an apple it gains both kinetic and potential energy, as opposed to the usual picture where the gain in kinetic energy is offset by an increasingly negative potential energy.

 

[enlightenment]

Claim #1:

The first law of thermodynamics says matter/energy cannot come from nothing.

True. Undisputed.

Claim #2:

Therefore, the universe itself could not have formed naturally.

It would seem that way, but I really have never investigated it that far. I just assumed that there was always matter and/or energy, and that they just get converted between one another.

Claim #3:

Talk Origins: Formation of the universe from nothing need not violate conservation of energy.

Yes it would. If something came from nothing, this clearly violates the first law.

Claim #4:

Talk Origins: The gravitational potential energy of a gravitational field is a negative energy.

Ok, how could you know what the potential energy of the gravitational field itself was? The field is simply defined as the volume around the object where it exerts its gravitational influence.

Claim #5:

Talk Origins: When all the gravitational potential energy is added to all the other energy in the universe, it might sum to zero.

I agree. However, this doesn't say whether something can come from nothing, nor does it say how matter and energy can come into existence without violating the first law.

Claim #6:

This response is seriously flawed. Mathematically energy is:
E = fd
E = energy.
f = force.
d = distance over which the force acts over.
If the force is negative then mass is pushed in a negative direction.
E = (-f)(-d) = fd

Not necessarily. If the force is negative, but the object is moving in opposition to the force, then the distance is positive.
W = (+F)(-d) = (-)

However, if an object's only interaction is with the gravitational field of the earth, the object cannot have negative work done on it.

The result is that the energy is still positive. For energy to be negative the force would have to push the mass in the opposite direction from which it is applied.
E = f (-d)
The result is the negative energy makes no mathematical sense.

It can make mathematical sense; this is an amateur.

(still adding material)...

 

[enlightenment]

Now the force of gravity is negative as a vector since it is always pulling a mass down. So the formula for gravitational force can best be written as:

g = - GmM/r^2

g = gravitational force.

m = mass 1.
M = mass 2.

r = distance between the center of each mass.

G = the gravitational constant.

True.

The potential energy ( P ) of a gravitational field is obtained by integrating the force of gravity over the distance from to .

Such that:

...

Well, the calculations appear accurate to me. The logic seems accurate.

I still don't see how a field itself can have potential energy.

 

[Physics_guy]

The energy stored within the curvature of spacetime is what is "negative" energy. Trying to answer questions about General Relativity with Newtonian physics is a bad idea. Also, it helps when you get the initial equations right.